Vol III sec I tech specification IPDS...24 7/10 SWG hot dip galvanized steel stay wire 240-242 25 G.S wire size 6 SWG and 8 SWG 243-245 26 11 KV CTPT metering sets 246-253 27 Solar

Technical Specification

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INDEX S.No. Technical Specification Item’s Name Page no.

PREFACE- TECHNICAL SPECIFICATION 6-9 TECHNICAL SPECIFICATION FOR THE VARIOUS ITEMS

1 9 Mtr. 400 KG PCC Pole 10-19

2 9 Mtr. 200 Kg. PCC pole 20-29

3 8 Mtr. 200 Kg.PCC Pole 30-39

4 33 KV Pins for 33 KV Pin insulator 40-49

5 11 KV Pins for 11 KV Pin insulator 50-59

6 M.S forged L.T.pins and hardware fittings for L.T. shackle insulators

60-72

7 33 KV/11 KV /LT Pin Insulators 73-76

8 33KV, 800 AMP. isolators with & without earth switch with 24 KV post insulators and 11KV , 400 AMP. isolators with 24 KV post insulators without earth blade

77-91

9 Various Steel Items 92-96

10 Sub-Station structure for mounting of 11/0.4 KV transformers on double pole / 33 KV line DP structure/ 33 KV sub-station structure and sub-station structure for single phase 16 KVA DT

97-101

11 Heat shrinkable type 33 KV & 11 KV indoor/ outdoor cable end terminations and straight through joints for XLPE cables

102-110

12 hot dip galvanised steel stay sets of size 16x1800mm and 20x2400mm

111-117

13 danger label/ plates for 33/11 KV & 11/0.4 KV sub- stations

118-120

14 36 KV indoor type vacuum circuit breakers 121-146

15 36 KV outdoor vacuum circuit breakers 147-158

16 ISI marked PVC insulated multi-core un-armoured NON-FRLS control cables

159-165

17 11 KV cross-linked polyethylene (XLPE) insulated power cables (3CX185)

166-173

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S.No. Technical Specification Item’s Name Page no.

18 400 AMP. & 200 AM P LT distribution kiosk suitable for 250/315 KVA & 63/100 KVA distribution transformers respectively

174-188

19 (A) 33 KV line DP (B) 1.8 metre long ms channelbracket with clamp (C)1.4 metre long ms channel bracket with clamp

189-191

20 33 KV control and relay panels 192-208

21 11 KV 2 MVAR capacitor bank with associated equipments

209-231

22 M.S.BOLTS & NUTS of assorted size 232-236

23 Hot dip galvanised steel stay wire with clamps and G.I wire

237-239

24 7/10 SWG hot dip galvanized steel stay wire 240-242

25 G.S wire size 6 SWG and 8 SWG 243-245

26 11 KV CTPT metering sets 246-253

27 Solar Panels 254-258

28 33 KV horn gap fuse sets with post 2X24 KV insulators (UN-ASSEMBLED) & 11 KV horn gap fuse sets with 1X24 KV post insulators (UN-ASSEMBLED)

259-270

29 P.G. CLAMPS for dog, panther conductor and T-clampfor panther conductor

271-276

30 (1) 11 KV 45 KN disc insulators T & C type. (2) 11 KV 45 KN disc insulators B & S type

277-280

31 LT pin insulators and 11 KV & 33 KV guy (stay) insulators for 11 KV & 33 KV transmission and L.T.distribution overhead power lines

281-286

32 33 KV cross arm (angle) with clamp and top hamper (A) 11 KV cross arm (angle) with clamp and top hamper (B) 11 KV top hamper (without clamp) &33 L.T.cross arm (600 MM) with clamp and L.T.cross arm (1200 MM) with clamp

287-288

33 110V- 120 AH maintenance free battery sets 289-294

34 33 KV (D/C) lattice structure (42’ LONG) ungalvanised along with 3 NOS. cross arm (channel) and Nuts & Bolts

295-297

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35 30 KV 10 KA heavy duty surge arresters (lightning arresters)

298--302

36 9 KV 10 KA heavy duty surge arresters (lightning arresters)

303-307

37 11 kV Drop Out Fuse Cut Outs 308-319

38 LT Ariel bunched cable 320-325

39 Four core and two core LT XLPE insulated & PVC sheathed armoured cable

326-335

40 12 KV Outdoor Vacuum Circuit Breaker Kiosks. 336-355

41 Battery Chargers Suitable For 110v-120 Ah Capacity Battery Sets

356-364

42 Hot Dip Galvanised Steel Stay Wire 7/8 SWG 365-369

43 Outdoor Type 33 KV CTS 370-381

44 hardware fittings for 11 KV,45 KN disc insulators tongue & clevis type & hardware fittings 11 KV,45 KN disc insulators Ball & Socket type

382-388

45 hardware fittings for 120 kn disc insulators `B&S' type (bolted type single tension clamp suitable for ACSR `panther' conductor & linked with 120 KN disc insulator)

389-393

46 ISI marked various sizes of four core LT XLPE insulated and PVC sheathed armoured cables.

394-409

47 33KV cross-linked polyethylene (XLPE) insulated power cables

410-428

48 NFC TYPE anchor (dead end) & suspension assemblies for LT aerial bunched XLPE insulated aluminium conductor cables with bare messenger wire

429-447

49 L.T. Insulation Piercing Connectors Suitable for LT XLPE insulated aerial bunched cables with bare messenger wire

448-458

50 ACSR panther conductor 459-473

51 LT XLPE insulated ACSR RABBIT conductor 474-487

52 3.15 MVA 33/11 KV power transformers 488-527

53 5.0 & 8.0 MVA 33/11 KV power transformers 528-568

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54 11/0.433KV, 25 KVA rating aluminium wound outdoor type completely self protected three star rating distribution transformers with meter protection box

569-613

55 11/0.433KV, 63&100 KVA rating aluminium wound outdoor type completely self protected three star ratingdistribution transformers with meter protection box

614-654

56 11/0.433KV, 160 KVA rating outdoor type (aluminium wound) three star rating distribution transformers

655-696

57 11/0.433KV, 315 KVA rating outdoor type (copper wound) distribution transformers

697-738

58 11/0.433KV, 500 KVA rating outdoor type (copper wound) distribution transformers

739-780

59 HT & MIP sheet metal meter boxes 781-795

60 11 KV XLPE insulated aluminium conductor aerial bunched cables along with accessories

796-809

61 FOR ACSR dog conductor 810-826 62 100 AMP. LT distribution kiosk suitable for underground

cabling and change over 827-836

63 11 KV 4 WAY feeder pillar (HT pillar box) 837-845 64 Spring loaded constant pressure multi connection bus

bar distribution box for single phase supply system. 846-859

65 Spring loaded constant pressure multi connection bus bar distribution box for three phase supply system.

859-874

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PREFACE- TECHNICAL SPECIFICATION

1.0 It is not the intent to specify completely herein all details of the design and construction of equipments. However, the equipment shall conform in all respects to high standards of engineering, design and workmanship and shall be capable of performing in continuous commercial operation upto the Bidder’s guarantee in a manner acceptable to the Purchaser, who will interpret the meanings of drawings and specifications and shall have the power to reject any work or material which in his judgment is not in accordance therewith. The offered equipment shall be complete with all components necessary for its effective and trouble free operation along with associated equipments, interlocks, protection schemes etc. Such components shall be deemed to be within the scope of supply, irrespective of whether those are specifically brought out in this specification and/or the commercial order or not.

The plant/ equipment/ material offered shall be complete with all parts necessary for their effective and trouble free operation. Such parts will be deemed to be within the scope irrespective of whether they are specifically indicated in the Bid document or not.

Bidder must establish that a proper quality assurance program is being followed by them for manufacture of plant / equipment. Quality assurance Program must have a structure as detailed in following paragraphs.

Quality assurance and failure prevention starts with careful study and scrutiny of our technical specifications & requirements. Bidder / manufacture shall carefully study all the technical parameters and other particulars and the Bidder /manufacture shall categorically give his confirmation that these requirements shall be met in a satisfactory manner.

Bidder/manufacture shall furnish the checks exercised in design calculations The salient features of design shall be made available to the Employer.

Bidder/manufacture shall indicate the various sources of the items being procured. Type of checks, quantum of checks and acceptance norms shall be intimated and random test and check results should be made available for inspection whenever so desired.

The Bidders shall invariably furnish following information.

i. Statement giving list of important raw materials, names if sub-

Bidder/manufactures for the raw material, list of standards according to which the raw material is purchased & copies of test certificates thereof.

ii. Information & copies of test certificates as in (i) above in respect of bought

out items.

iii. List of machines & manufacturing facilities available.

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iv. Levels of automation achieved and list of areas where manual processing exists.

v. List of areas in manufacturing process, where stage inspections are normally

carried out for quality control & details of such tests and inspections.

vi. List of testing equipments available with the bidder for testing of materials

specified & test plant limitation, if any, vis-a-vis type, special, acceptance and routine tests specified in the relevant standards. These limitations shall be very clearly brought out in schedule of deviations from specified test equipments.

2. Pre-dispatch Inspection:

2.1 Pre-dispatch inspection shall be performed on various materials at

manufacturer’s work place for which contractor shall be required to raise requisition giving at least 15-day time. Depending on requirement, inspection shall be witnessed by representatives of Employer, PMA/TPIA and/or REC/MoP or any appointed agency.

2.2 The contractor shall ensure receipt of material at site within 21 days from date

of receipt of dispatch instructions. In case materials are not received within 21 days from date of issue of dispatch instruction, the dispatch instruction shall stand cancelled. All expenditure incurred by Employer in performance of dispatch instruction shall be recovered from partial turnkey contractor.

2.3 The Employer’s representative may carry out stage inspection of the plant/

equipment during manufacturing/ assembling stage. The Employer shall have absolute right to reject the raw material/component/sub assemblies or complete equipment not found to be conforming to the specification or being of poor quality/ workmanship. The stage inspection will particularly include tests specified for any particular plant or equipment in the technical specification, general routine tests and physical measurements to be conducted during manufacturing stages as per manufacturer’s standard practice.

2.4 The date of receipt of the letter /call for inspection of material in the office of the work order placing authority shall be deemed as the date of call for inspection and not the date mentioned in the letter or the date of dispatch. The turnkey contractor shall ensure that pre-dispatch inspection for materials are intimated only when the material is completely ready for inspection. On due date of inspection, if it is found that materials are not ready in required quantities or the inspection could not be carried out due to non-availability of requisite calibrated certificate of instruments with manufacturer, closing of works on scheduled date of inspection, non-availability of sufficient

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testing/material handling staff at manufacturer works etc, all expenditures incurred on deployment of various inspecting officials along with a fine of Rs 50,000/- shall be recovered from the bills of the agency and re-inspection shall be carried out on expense of contractor. 2nd such situation at same manufacturer/supplier shall result in rejection of name of manufacturer from list of approved vendors/sub-vendors. In case sub-standard materials (old component, re-cycled materials, re-used core material, re-used transformer coil material etc) offered for inspection and are noticed during the inspection, materials shall be rejected and approval of vendors/ sub-vendor shall also be cancelled for all IPDS projects.

2.5 In case material is failed in testing at works or at CTL lab , then re inspection of material shall be done after depositing of amount of Rs.7500/- only for the works located in the State of Rajasthan and an amount of Rs.15,000/- for the works located outside the State of Rajasthan which shall be paid by the contractor as re- inspection charges to the Accounts Officer (TW), JVVNL, Jaipur. Further, in cases where traveling by air is involved the inspection charges will be recovered on actual basis. The contractor will deposit the amount with the Accounts Officer (TW), JVVNL, Jaipur under intimation to the work order placing authority, failing which the subsequent call for inspection shall not be entertained.

. 2.6 The contractor shall also furnish the latest calibration certificate(s) of the

testing instruments / equipments used for the testing of the materials / equipments as covered in the owner order, to the inspecting Officer. The testing instruments / machines should be got calibrated by the contractor from time to time from the Manufacturer of the testing instruments or any Govt. recognized testing laboratory/NABL accredited laboratories. The calibration certificate(s) should not, in any case, be older than one year at the time of presenting the same to the inspecting Officer. In case the contractor fails to comply with the conditions as aforesaid, a certificate in writing of the inspector / representative of the Owner that the contractor has failed to provide the facilities shall be conclusive.

3. TYPE TEST 3.1 The type test certificate for any item shall not be more than five (5) years old from

the date of submission of the bid. 3.2 The Employer may get the Type test or routine tests of any equipment done at

Accredited Laboratory by NABL in the country. The type test may be done even after receipt of materials at contractor’s site store but not after the guarantee period for the equipment as described elsewhere. The results of such tests will be decided on pass fail basis. In case the equipment fails to pass the Type test , the cost of such test shall be borne by the Contractor.

3.3 The Bidder /manufacturing programme shall not be interrupted merely because the

plant/equipment has been offered for inspection.

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3.4 Specification for individual plant /equipment is subject to the conditions mentioned above.

3.5 The bidder shall prior to use any material in execution of the work for which

technical specification have not been mentioned will use any material after obtaining necessary approval of GTP & Drawing from SE(TW),J.V.V.N.L.,Jaipur.

3.6 If bidder intend to use any material with superior specification then that as specified in the bid document. The prior approval of SE(TW),J.V.V.N.L.,Jaipur shall be obtained before use and the rates for such substitution will be limited to as per the awarded rates.

4 PROCUREMENT FROM MANUFACTURERS / VENDORS:

The Contractor shall be permitted to procure materials from the manufactures /

vendors who have following qualified requirements:

(i) The vendor should be a established / reputed manufacture / supplier who should have supplied the material to erstwhile RSEB or any present distribution company, RVVPNL or any other power utility and the contractor / bidder are required to indicate the names & address of the manufactures of various items from which he proposes to buy the same.

(ii) The manufacturing units shall have all facilities for conducting acceptance &

routine tests of equipment / materials.

(iii) The vendor must have supplied materials as per specifications laid down in the bid- documents of erstwhile RSEB / NIGAMS and have arranged their type testing not before last five years,

(iv) The vendors approvals shall be obtained for supply of the equipment /

materials from the Engineer well in advance. (v) All steel items shall be supplied galvanized as per ISS

Note:- Latest Technical specifications and guaranteed technical particulars of MM

wing of Jaipur Discom will prevail for all the items incorporated in this

project. However Technical Specifications of some of the major items are

given hereunder for ready reference.

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Technical specification for the various items

TECHNICAL SPECIFICATION FOR SUPPLY OF 9 M. LONG PCC POLES OF 400 KG WORKING LOAD WITH FACTOR OF SAFTY 2.0,

1. SCOPE :

This specification covers the design, manufacture, inspection, testing and delivery of finished 9 metre long- 400 Kg. rectangular shaped, solid prestressed cement Concrete poles, witnessing of tests before dispatch and its transportation from the firm’s works to consignee’s head quarters. These poles are to be used for erection of 33 KV /11 KV over head lines and installation of transformers.

2. CLIMATIC CONDITIONS

I. Peak ambient temperature 50 Degree C II. Maximum average ambient temperature 40 Degree C

III. Maximum temperature attainable 60 Degree C IV. Maximum relative humidity 100 %V. Minimum relative humidity 50 %VI. Average number of thunder storm days per annum 40VII. Average number of rainy days per annum 100

VIII. Average annual rainfall 10-100 cm IX. Maximum wind pressure 100 Kg/sq.m X. Altitudes not exceeding 1000 mtrs.

3. DETAILS OF APPLICABLE STANDARDS/SPECIFICATION/MANUALS :

The pole shall comply with the relevant provisions made in the following Indian Standards Specification (now BIS) with latest amendments / REC specifications.

1 REC manual No.13/1977

(part-I)

Manual on manufacturing of solid poles part- I design aspects.

2 REC manual No.13/1977 (Part.II) Manual on manufacturing of solid PCC poles part.II manufacturing aspects.

3 REC specification No.15/1979 (amended upto 1983 & thereafter

Prestressed cement concrete poles (FOS/2.5) for 11 KV and LT lines.

4 IS:1678/1978 (Latest amended) Specification for PCC poles for overhead power

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traction & telecommunication lines.

5 IS:2905/1989 (Latest amended) Method of test for PCC poles for overhead power and telecommunication lines.

6 IS:7321/1974 (Latest amended) Code of practice for selection handling and erection of concrete poles for overhead power and telecommunication lines.

7 IS:1343/1980(Latest amended) Code of practice for prestressed concrete

8 IS: 456/1978 (Latest amended) Code of practice for plain and reinforced concrete

9 IS: 1785(Latest amended) For HT steel wires for prestressed concrete

4. MATERIAL

The following quality of material should be used for manufacturing of PCC poles.

(i) CEMENT : The cement used in manufacture of prestressed concrete poles shall be ordinary or rapid hardening portland cement conforming to IS:269/1976 (specification for ordinary and low heat portland cement) or IS:8041-E-1978 (specification for rapid hardening portland cement) or portland cement conforming to IS:8112/1976.

(ii) AGGREGATES : Aggregates used for the manufacture of prestressed concrete poles shall conform to IS:383/1970 (specification for coarse and fine aggregates from natural sources for concrete). The nominal maximum size of fine aggregates shall not exceed 10 mm.

(iii) WATER :Water should be free from chlorides, sulphates other salts and organic matter. Potable water is generally suitable.

(iv) ADMIXTURES : These admixtures should not contain calcium chloride or other chlorides and salts which are likely to promote corrosion of pre-stressing steel.

(v) ) PRE-STRESSING STEEL : The prestressing steel wires including those used as untentioned wires should conform to IS:1785 –1966 Part.I (Specification for plain hard drawn steel wire) or IS:"6003/1970 (Specification for indented wire for prestressed concrete). The type design for plain wires of 4 mm diameter are with a guaranteed ultimate strength of 175 Kg./sq.mm.

(vi) CONCRETE MIX : The concrete mix. shall be designed to the requirements laid down for controlled concrete (also called design requirement laid down/mix. concrete) in IS:1343/1980 (Code of practice for prestressed concrete) and IS:456/1978 (code of practice for plain and reinforced concrete) subject to the following special conditions :

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a) Min. working cube strength at 28th day should be at least 420 Kg. / cm.2

b) The mix. should contain at least 380 Kg. cement per cubic metre of concrete. c) The concrete strength at transfer should be at least 210 Kg. / cm.2

d) The mix. should contain as low water content as is consistent with adequate workability. If it becomes necessary to add water to increase the workability the cement content should also be raised in such a way that the original value of water cement ratio is maintained.

(vii) REINFORCEMENT : The reinforcing bars and wires used for manufacturing of prestressed cement concrete poles shall conform to the following Indian standards.

i) Mild steel bars conforming to IS:432/1966. ii) High tensile steel wires conforming to IS:1785/1966.

(viii) WELDING AND LAPPING OF STEEL: The high tensile steel wire shall be continuous over the entire length of the tendon. Welding shall not be allowed in any case. However, jointing or coupling be permitted provided the strength of the joint or coupling is not less than the strength of each individual wire.

5. DESIGN REQUIREMENT :

The poles shall be designed to meet the following requirements.

a) The poles shall be planted directly in the ground with a planting depth of 1.5 metres. b) The working load on the poles shall be 400 Kg. applied at 0.6 Mtr. from top. c) The factor of safety shall not be less than 2.0. d) The average permanent load should be 40% of the working load. e) The Factor of safety against first crack load shall be 1.0 f) The ultimate moment capacity in the longitudinal direction should be atleast

one fourth of that in the transverse direction. g) The max. compressive stress in concrete at the time of transfer of presetress

should not exceed 0.8 times the cube strength. h) The concrete strength at transfer shall not be less than half of the 28th day strength

ensured in the design i.e. : 420x0.5 = 210 KG./SQ.MM. i) The cover concrete measured from outside of prestressing tendon shall be normally

20 mm. j) At the design value of first crack load the modules of rupture shall not exceed 55.2

Kg./cm for M-42 concrete. 6. OPTIMUM DESIGN DIMENSIONS :

Bottom depth. : 395 mm Top depth. : 225 mm Breadth. : 100 mm No. of tensioned wire : 20 Nos. wires of 4 mm dia. Configuration type. : JVVNL specification

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7. OTHER TECHNICAL REQUIREMENT : A) EARTHING : Earthing shall be provided, by having continuous length of 4 mm dia G.I.wire embeded in concrete during manufacture and the ends of G.I. wire left projected from the transverse face of the poles to a length of 100 mm at 250 mm from top and 150 mm below ground level (Planting depth to be 1.5 M) The tolerance of 25 mm shall be allowed in position of earth wire. The earth wire shall not be allowed to entangle with prestressing wires.

B) EYE HOOKS : The eye hooks shall be provided on the middle of transverse face of the pole as per IS: 7321/1974 at a distance of about 2.25 metre from top and about 1.8 metre from the bottom, to facilitate the handling. The eye hooks shall be of 12 mm dia MS round and shall have an internal dia of 40 mm. The tolerance of minus 5 mm and plus 20mm in internal dia of eye hooks shall be allowed. the eye hooks in question shall be securely embeded in the pole to ensure safe handling.

C) REINFORCEMENT : The poles offered should have 8 Nos. rings of 4 mm dia HT wires rings on top side of the pole and 8 Nos. rings of 4 mm dia HT wire rings on the bottom side of the pole thus total HT wire rings should be 16 in all or 4 Nos. of 6 mm dia MS round rings on top side and 4 Nos. of 6 mm dia MS round rings on bottom side are to be provided. The minimum inter spacing of 20 mm in case of 4 mm dia HT wire rings and 30 mm in case of 6 mm dia MS round rings is to be maintained. These rings should be complete and rectangular in shape with minimum over lapping of 20 mm. No rings are to be bunched together.

D) HOLES : The poles offered should have two holes of 18 mm dia on longitudinal face of pole (broad face) to fix top hamper. The top hole shall be at the distance of 60 mm from top of pole and second hole will be at 160 mm from top of pole.

8. WORKMANSHIP :

(i) All materials used in the finished PCC poles and workmanship shall be of required quality. No deviation with technical particulars required as per this tender specification shall be allowed.

(ii) Apart from the requirements regarding the design, material, process of manufacture, dimensions shape, workmanship finishing etc., acceptability of PCC poles shall be determined by the results of various tests to evaluate their properties as stipulated in the relevant IS/specification.

9. DRAWINGS :

The tenderer shall furnish alongwith the tender the detailed dimensional drawing based on the JVVNL drawing (enclosed) showing the plan, elevation and end cross sectional views clearly indicating the configuration of HT wire size and No. of HT-wires, eye-hook's position & projection of earth wire marking & reinforcement. The drawing is also required to be got approved before commencement of supply.

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10. MARKING :

(A) The poles shall be clearly & indelibly marked with the following particulars by

engraving properly at a height of 3 metres from the bottom end so as to be easily readable after erection. Marking should not be painted.

1. S.No. of pole. 2. Date, month and year of manufacture. 3. Name/mark of manufacturer.

It should be distinct and should not resemble with mark of other manufacturers and if it resembles with marking of other manufacturers then you should change your marking.

4. IPDS/ TN/JVVNL

5. Length and working load 9 M/400 Kg. (B) RED STRIP PAINTING: A strip of 30-40 mm shall be painted on one side (transverse face) of the pole at a planting depth (1.5 Metre from bottom) with oil paint of red color in such a manner that the red strip shall be visible above the ground. Poles without marking of red strip will not be accepted and considered as rejected.

11. INSPECTION, TESTING & CHECKING :

The inspection and testing shall be carried out at supplier’s works as per relevant ISS: GTP before dispatch.

The supplier shall incorporate the following certificate in his offer letter which should indicate Sr. No. & total No. of poles casted on different dates, as offered for the present inspection :

a) That all the PCC poles included in the lot under the present inspection conform to the design, strength and workmanship required as per the purchase order, GTP of the specification and contract drawing under the TN-4469.

b) That none of the PCC poles offered for the present inspection was previously rejected / not considered for inspection or tested for transverse load strength by any other inspecting officer.

The supplier shall furnish the following certificates / tests results to our Inspecting Officer at the time of inspection, if desired.

a) The supplier shall furnish test results from the manufacturer to substantiate that HT steel wire of required quality was used in the manufacture of PCC poles under the present inspection.

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b) The supplier shall certify that cement, prestressed steel wires, M.S. Bars, aggregates and other material had been used as per the required specifications, to manufacture the PCC Poles under the present inspection.

The supplier shall arrange the required number of PCC Poles out of the offered lots as per the sampling plan under this specification for witnessing the various tests by Inspecting Officer. The poles so tested in presence of the Inspecting Officer shall be preserved for atleast 30 days from the date of inspection for subsequent checking by any other representative for the purchaser if needed. The supplier shall intimate in writing name and address of purchaser of tested poles otherwise the PBG will not be released.

The supplier shall provide the following documents to Inspecting Officer, to facilitate and authenticate the process of inspection, checking and testing.

a) One set of copies of P.O., relevant IS and specification of TN (with the latest amendment, if any)

b) Copy of approved Drawing.

c) Details of all meters/ instruments /equipments to be used in the process of checking and testing of the material alongwith the details for their last calibration (original) certificates of calibration indicating that calibration had been done to full range on all the scales to verify that the last calibration and sealing was got done from the manufacturer or an independent test house approved by Government within one year prior to the date of inspection.

Inspection shall not be carried out further, if the above requirements are not fulfilled satisfactorily.

A. SAMPLING: a) Randomness is the pre requisite for sample checking and testing. Starting from any random serial number or PCC poles in the offered lot (arranged serial number wise and sub-divided sub-lots each not exceeding 500 Nos. of poles) every pole shall be included in the sample "r" being the next higher integral part of N/n where N is the size of the lot or sub-lot and “n" is the sample size as per the table below:-

Sample size and criterion for conformity :

Size of lot or sub-lot in

numbers (N)

Dimensional requirement No.of poles for transverse strength

test (n) sample size

(n)Permissible No. of defective samples

1 2 3 4 Upto 100 10 1 1

101 to 200 15 1 3 201 to 300 20 2 4 301 to 500 30 3 5

The minimum size of lot which can be offered for inspection is 100 Nos. of pole except in case of last lot which may be for left out balance quantity. Further lot size once

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offered for inspection can’t be reduced subsequently under the re-inspection unless re- inspection charges for each sub-lot out of the original lot is deposited.

b) Deviation in selection of samples may be effected by the Inspecting Officer only if he thinks that the purpose of checking/testing will be better served by such deviation.

c) The number of poles, in every lot/sub lot, which does not satisfy, the requirement of overall length, cross section and uprightness shall not exceed the corresponding number given in Col.3 of the above Table. If the number of such poles exceeds the corresponding number, supplier shall segregate the pole not confirming the requirement of specification and shall submit the remaining poles for checking. Fresh poles as per sample size indicating in Col.2 will be drawn from the remaining poles of the offered lot or sub lot and subject to similar checking. If the number of effective poles in the second sample of poles also exceeds the permissible number indicated in Col.3 the then the subject lot or sub lot under inspection will be rejected without further checking. Result of all such checking shall be recorded.

d) PCC poles, in every lot/sub lot sampled for transverse load strength test shall satisfy the requirement of the test. Initially selection of sample and inspection and testing of poles will be undertaken as usual as is being done according to IS:1678/1998 and IS:2905/ 1989 with latest amendments. In case the samples selected satisfied the dimensional requirements and also withstand transverse load test, the lot stands cleared.

In case of one or more poles fail during transverse load test, then twice the number of poles from the sub-lots representative poles from which failed will be taken for transverse load test. If these poles withstand the transverse load test the entire lot will be deemed to have passed the tests and will be cleared, but if one or more pole fails during double sampling, then leaving aside the sub-lots for which double sampling was done and where samples could not withstand transverse load test, the remaining sub-lots representing poles from which have withstood transverse load test will be accepted provided they satisfy clause No. 9.3.2 of IS:1678/1978. However, the destruction test from the sub-lots will be done by the inspecting officer on the poles on which transverse load was performed and the acceptance of these sub-lots will be on the basis of the test results observed by the inspecting officer during destruction test on the respective representative poles.

e) All the poles subject to transverse load strength test shall be reserved for atleast 30 days from the date of inspection for any subsequent checking by any other representative of the purchaser, if required. These poles shall not be dispatched /supplied to the purchaser.

f) One pole from the poles subject to transverse load strength test, from every lot/sub lot, shall be destructed for following measurement/checking.

i) To measure clear thickness of concrete cover at three points one within 1.8 metre from the bottom end of the pole, the second within 0.6 metre from the top end of the pole and the third at an inter-mediate point. The mean value shall be compared with the specified value.

ii) To check Nos., size & configuration of steel reinforcement and GI earth wire.

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The destructed poles shall also be preserved for atleast thirty days from the date of inspection for subsequent checking by any other representative of the purchaser if required.

B) INSPECTION : Inspection shall comprise of : a) Verification of offered quantity as per packing list b) Visual inspection for shape, workmanship and finishing of the PCC poles. c) Checking of dimensions/quantity as per the GTP/specification d) Verification of marking and red / black strip as per GTP

C) WITNESS OF TESTS :

i) On PCC poles for its transverse load strength test . ii) On one PCC pole from every lot/sub lot by destruction to ascertain the No.,

size and configuration of steel reinforcement and GI earth wire etc. The supplier should have transverse load testing arrangements of its own. Testing arrangement shall be preferably as specified in the relevant specification i.e. IS:1678/1978 & IS:2905/1989 (both latest amended). As per provision of Clause No.6.2.3 of IS:2905/1989 the load shall be applied at a point stipulated in the relevant IS by means of a suitable device such as a wire rope and winch placed in a direction normal to the direction of the length of the pole so that the minimum length of the straight rope under pull is not less than the length of the pole.

As per provision of Clause No.6.2.5 "load measurement" of IS:2905/1989. The dynamometer or any other satisfactory method of load measurement shall be calibrated at regular intervals (not more than one year) and capable of measuring load to the accuracy of 50 N may be adopted.

The transverse strength test on poles shall be conducted in accordance with IS:2905. A prestressed concrete pole shall be deemed not to have passed the test if cracks wider than 0.1 mm appear at a stage prior to the application of the designed transverse load at first crack and the observed ultimate transverse load is less than the designed ultimate transverse load.

The following facilities are to be provided by the supplier at his own cost to the inspecting officer of JVVNL.

(a) Suitable accommodation. (b) Local conveyance between arrival point, place of stay, works and departure

point. (c) The supplier shall assist in arranging return ticket and reservation on the request

of the inspecting officer for which the payment shall be made by the inspecting officer. In case of joint inspection, single or shared double room accommodation shall be provided.

18

12. TEST AT SITE : The purchaser reserves the right to get the material tested after receipt of inspected poles at sites/ stores and claiming any compensation or rejecting the poles if not found according to specification. All charges consequent to rejection, rectification and replacement shall be borne by the supplier.

13. TOLERANCE : The following tolerances shall be allowed :

i) Over all length of PCC poles. ±15 mm ii) Top and bottom dimension. (Breadth and depth of PCC poles) ± 3 mm iii) Clear concrete cover over HT steel wires (Average of

measurements at three sections). - 2 mm iv) Uprightness of the PCC poles. 0.5 % v) Internal dia of eye hook + 20 mm and – 5 mm vi) Dia of holes ± 1 mm vii) Diameter of HT wires as per IS: 280/1979 ± 0.05 % viii) Diameter of GI wire as per IS:280/1979 ± 2.5% ix) Diameter of MS rod for eye hook as per 1786/1966 ± 4%

Higher dimensions of poles shall attract no penalty / deduction as it will not be considered as deviation.

14. GUARANTEED TECHNICAL PARTICULARS :

The tenderer shall furnish the guaranteed technical particulars of the PCC poles as required in the schedule-A by mentioning specific figures therein. Any item of the GTP left unfilled or simply written as per ISS etc. shall be considered as incomplete GTP.

15. TRANPORTATION ARRANGEMENTS :

The tenderer must furnish the location of the factory and road distances from their factory site to various destinations (sub-divisional headquarters of JVVNL) through shortest route.

The tenderers should also furnish the particulars of transportation vehicles owned by them.

16. CRITERIA FOR ACCEPTANCE:

The inspected PCC poles should be strictly in accordance to the GTP of the specification otherwise the material shall be treated as rejected and shall not be accepted. However, the poles with some minor deviations may be accepted with deductions as per rates prescribed and in force.

Higher dimensions of poles shall not attract any penalty / deduction, as it will not be considered as deviation.

19

SCHEDULE-A

GUARANTEED TECHNICAL AND OTHER PARTICULARS OF 9 METRE PCC POLES HAVING WORKING LOAD 400 KG. WITH FACTOR OF SAFETY 2.0

S.No. Particulars Requirement as per GTP

1 MANUFACTURER’S NAME

2 OFFICE ADDRESS

3 WORKS ADDRESS

4 STANDARDS TO WHICH THE MATERIAL SHALL CONFORM

As per specification

5 OVER ALL LENGTH 9 metre 6 PLANTING DEPTH 1.5 metre 7 TOP DIMENSIONS IN MM 225x100 mm 8 BOTTOM DIMENSIONS IN MM 395x100 mm 9 APPROXIMATE WEIGHT 675 Kg. 10 WORKING LOAD 400 Kg. 11 FACTOR OF SAFETY (F.O.S.) 2.0 12 NO. & DIA OF HT WIRE (TENSIONED) 20 ( 4 mm dia) 13 CONFIGURATION OF HT WIRE As per approved drawing 14 POSITION OF EARTH WIRE LENGTH

AND SIZE OF WIRE G.I. wire of 4 mm dia having continuous length with a projection of 100 mm at 250 mm from top and 150 mm from below ground level.

15 DIMENSIONS AND POSITION OF EYE HOOKS

2 Nos. of Eye hook of 12 mm dia M.S. round having internal dia of 40 mm at 2.25 metre from top and 1.8 metre from bottom

16 REINFORCEMENT (SIZE AND NO. OF RINGS)

8 Nos. of rings of 4 mm dia HT wires on top and 8 Nos. of rings on bottom (both ends) with minimum inter spacing of 20 mm.

17 CONCRETE COVER 20 mm 18 MARKING ON THE POLES Marking should be engraved on transverse

face19 RED STRIP A strip of 30-40 mm shall be painted with

oil paint of red colour, on one side (transverse face) of the pole at a planting depth (1.5 Metre from bottom)

20 HOLES POSITION 2 holes of 18 mm dia at 60 mm and 160 mm from top on longitudinal face of the pole(broad face).

21 CONCRETE QUANTITY PER POLE 0.279 M3

22 CONCRETE GRADE M-42 Note:- Max. tension in wire should not exceed 80% of its ultimate tensile strength.

Signature of the Bidder

Name Designation

Common authorized seal of bidder

20

TECHNICAL SPECIFICATION FOR SUPPLY OF 9 M. LONG PCC POLES OF 200 KG WORKING LOAD WITH FACTOR OF SAFTY 2.5, 1. SCOPE :

This specification covers the design, manufacture, inspection and testing 9 metre long- 200 Kg. rectangular shaped, solid prestressed cement Concrete poles, witnessing of tests before dispatch and its transportation from the firm’s works to consignee’s head quarters. These poles are to be used for erection of 11 KV & LT over head lines and installation of 11/.4 KV distribution transformers.


XI. Peak ambient temperature 50 Degree C XII. Maximum average ambient temperature 40 Degree C

XIII. Maximum temperature attainable 60 Degree C XIV. Maximum relative humidity 100 %XV. Minimum relative humidity 50 %XVI. Average number of thunder storm days per annum 40XVII. Average number of rainy days per annum 100

XVIII. Average annual rainfall 10-100 cm XIX. Maximum wind pressure 100 Kg/sq.m XX. Altitudes not exceeding 1000 mtrs.



1 REC manual No.13/1977 (part-I) Manual on manufacturing of solid poles part-

I design aspects.




4 IS:1678/1978 (Latest amended) Specification for PCC poles for overhead power traction & telecommunication lines.


6 IS:7321/1974 (Latest amended) Code of practice for selection handling and

21

erection of concrete poles for overhead power and telecommunication lines.




4. MATERIAL




(iii) WATER :Water should be free from chlorides, sulphates other salts and organic matter. Potable water is generally suitable.

(iv) ADMIXTURES :These admixtures should not contain calcium chloride or other chlorides and salts which are likely to promote corrosion of pre-stressing steel.


(vi) CONCRETE MIX :The concrete mix. shall be designed to the requirements laid down for controlled concrete (also called design requirement laid down/mix. concrete) in IS:1343/1980 (Code of practice for prestressed concrete) and IS:456/1978 (code of practice for plain and reinforced concrete) subject to the following special conditions :


b) The mix. should contain at least 380 Kg. cement per cubic metre of concrete. c) The concrete strength at transfer should be at least 225Kg. / cm.2

d) The mix. should contain as low water content as is consistent with adequate workability. If it becomes necessary to add water to increase the workability the

22

cement content should also be raised in such a way that the original value of water cement ratio is maintained.

(vii) REINFORCEMENT :The reinforcing bars and wires used for manufacturing of prestressed cement concrete poles shall conform to the following Indian standards.


(viii) WELDING AND LAPPING OF STEEL: The high tensile steel wire shall be

continuous over the entire length of the tendon. Welding shall not be allowed in any case. However, jointing or coupling be permitted provided the strength of the joint or coupling is not less than the strength of each individual wire.



a) The poles shall be planted directly in the ground with a planting depth of 1.5metres. b) The working load on the poles shall be 200 Kg. applied at 0.6 Mtr. from top. c) The factor of safety shall not be lessthen 2.5. d) The average permanent load should be 40% of the working load. e) The Factor of safety against first crack load shall be 1.0 f) The ultimate moment capacity in the longitudinal direction should be atleast



ensured in the design i.e. : 450x0.5 = 225 KG./SQ.MM. i) The concrete cover measured from outside of prestressing tendon shall be 30 mm. j) At the design value the first crack load the modules of rupture shall not exceed 55.2

Kg. / cm for M-45 concrete 6. OPTIMUM DESIGN DIMENSIONS :

Bottom depth. : 300 mm Top depth. : 145 mm Breadth. : 114 mm No. of tensioned wire : 16Nos. wires of 4 mm dia. Configuration type. : JVVNL specification

7. OTHER TECHNICAL REQUIREMENT :

A) EARTHING : Earthing shall be provided, by having continuous length of 4 mm dia G.I.wire embeded in concrete during manufacture and the ends of G.I. wire left projected from the transverse face of the poles to a length of 100 mm at 250 mm from top and 150 mm below ground level (Planting depth to be 1.5 M) The tolerance of 25 mm shall be allowed in position of earth wire. The earth wire shall not be allowed to entangle with prestressing wires.

23

B) EYE HOOKS : The eye hooks shall be provided on the middle of transverse face of the pole as per IS: 7321/1974 at a distance of about 2.25metre from top and about 1.8metre from the bottom, to facilitate the handling. The eye hooks shall be of 12 mm dia MS round and shall have an internal dia of 40 mm. The tolerance of minus 5 mm and plus 20mm in internal dia of eye hooks shall be allowed. the eye hooks in question shall be securely embeded in the pole to ensure safe handling.

C) REINFORCEMENT :The poles offered should have 8 Nos. rings of 4 mm dia HT wires rings on top side of the pole and 8 Nos. rings of 4 mm dia HT wire rings on the bottom side of the pole thus total HT wire rings should be 16 in all or 4 Nos. of 6 mm dia MS round rings on top side and 4 Nos. of 6 mm dia MS round rings on bottom side are to be provided. The minimum inter spacing of 20 mm in case of 4 mm dia HT wire rings and 30 mm in case of 6 mm dia MS round rings is to be maintained. These rings should be complete and rectangular in shape with minimum over lapping of 20 mm. No rings are to be bunched together.


8. WORKMANSHIP :

(i) All materials used in the finished PCC poles and workmanship shall be of required quality. No deviation with technical particulars required as per this tender specification shall be allowed.

(ii) Apart from the requirements regarding the design, material, process of manufacture, dimensions shape, workmanship finishing etc., acceptability of PCC poles shall be determined by the results of various tests to evaluate their properties as stipulated in the relevant IS/specification.

9. DRAWINGS :

The tenderer shall furnish alongwith the tender the detailed dimensional drawing based on the JVVNL drawing (enclosed) showing the plan, elevation and end cross sectional views clearly indicating the configuration of HT wire size and No. of HT-wire, eye-hook's position & projection of earth wire marking & reinforcement. The drawing is also required to be got approved before commencement of supply.

10. MARKING :

(A) The poles shall be clearly & indelibly marked with the following particulars by

engraving properly at a height of 3 metres from the bottom end so as to be easily readable after erection. Marking should not be painted.

1. S.No. of pole. 2. Date, month and year of manufacturing 3. Name/mark of manufacturer.

24

It should be distinct and should not resemble with mark of other manufacturers and if it resembles with marking of other manufacturers then you should change your marking.

3. Length and working load 9 M/200 Kg. 4. IPDS/TN.

(B) BLACK STRIP PAINTING: A strip of 30-40 mm shall be painted on one side (transverse face) of the pole at a planting depth (1.5Metre from bottom) with oil paint of blackcolour in such a manner that the black strip shall be visible above the ground. Poles without marking of blackstrip will not be accepted and considered as rejected.

11. INSPECTION, TESTING &CHECKING :

The inspection and testing shall be carried out at supplier’s works as per relevant ISS: GTP

The supplier shall incorporate the following certificate in his offer letter which should indicate Sr. No. & total No. of poles casted on different dates, as offered for the present inspection :

a) That all the PCC poles included in the lot under the present inspection conform to the design, strength and workmanship required as per the purchase order, GTP of the specification and contract drawing under the TN-





The supplier shall arrange the required number of PCC Poles out of the offered lots as per the sampling plan under this specification for witnessing the various tests by Inspecting Officer. The poles so tested in presence of the Inspecting Officer shall be preserved for atleast 30 days from the date of inspection for subsequent checking by any other representative for the purchaser if needed. The supplier shall intimate in writing name and address of purchaser of tested poles otherwise the PBG will not be released.


25



c) Details of all meters/ instruments /equipments to be used in the process of checking and testing of the material alongwith the details for their last calibration (original) certificates of calibration indicating that calibration had been done to full range on all the scales to verify that the last calibration and sealing was got done from the manufacturer or an independent test house approved by Government within one year prior to the date of inspection.


A. SAMPLING:

a) In a consignment, 500 poles or a part thereof of the same overall length, same dimensions and belonging to the same batch of manufacturer shall be grouped together to constitute a lot.

For ascertaining the conformity of the materials in the lot to the requirements of the specification, samples shall be tested from each lot separately.

The number of poles to be selected from the lot shall depend on the size of the lot and shall be according to table as under:-


Size of lot or sub-lot

in numbers (N)

Dimensional requirement No.of poles for transverse

strength test (n)

sample size (n)

Permissible No. of defective samples

1 2 3 4 Upto 100 10 1 1

101 to 200 15 1 3 201 to 300 20 2 4 301 to 500 30 3 5

The minimum size of lot which can be offered for inspection is 200 Nos. of pole except in case of last lot which may be for left out balance quantity. Lot size once offered for inspection can not be reduced subsequently under the re-inspection, unless re- inspection charges for each lot / sub-lot out of the original lot is deposited.


26


d) PCC poles, in every lot/sub lot sampled for transverse load strength test shall satisfy the requirement of the test. Initially selection of sample and inspection and testing of poles will be undertaken as usual as is being done according to IS:1678/1998 and IS:2905/1989 with latest amendments. In case the samples selected satisfied the dimensional requirements and also withstand transverse load test, the lot stands cleared. In case of one or more poles fail during transverse load test, then twice the number of originally tested shall be selected from those already selected and subjected to the tests. If these poles withstand the transverse load test the entire lot will be deemed to have passed the tests and will be cleared, but if one or more pole fails during double sampling, then leaving aside the sub-lots for which double sampling was done and where samples could not withstand transverse load test, the remaining sub-lots representing poles from which have withstood transverse load test will be accepted provided they satisfy clause No. 9.3.2 of IS:1678/1978. However, the destruction test from the sub-lots will be done by the inspecting officer on the poles on which transverse load was performed and the acceptance of these sub-lots will be on the basis of the test results observed by the inspecting officer during destruction test on the respective representative poles.

e) All the poles subject to transverse load strength test shall be reserved for atleast 30 days from the date of inspection for any subsequent checking by any other representative of the purchaser, if required. These poles shall not be dispatched /supplied to the purchaser.





27

B) INSPECTION :

Inspection shall comprise of : a) Verification of offered quantity as per packing list b) Visual inspection for shape, workmanship and finishing of the PCC poles. c) Checking of dimensions as per the GTP/specification

C) WITNESS OF TESTS :

iii) On PCC poles selected for transverse load strength test as per sampling

plan. iv) On one PCC pole from every lot/sub lot be destructed to ascertain the No.,


As per provision of Clause No.6.2.5 "load measurement" of IS: 2905/1989. The dynamometer or any other satisfactory method of load measurement shall be calibrated at regular intervals and capable of measuring load to the accuracy of 50 N may be adopted.

The transverse strength test on poles shall be conducted in accordance with IS 2905. A

prestressed concrete pole shall be deemed not to have passed the test if cracks wider than 0.1 mm appear at a stage prior to the application of the designed transverse load at first crack and the observed ultimate transverse load is less than the designedultimate transverse load.

12. TEST AT SITE :

The purchaser reserves the right to get the material tested after receipt of inspected poles at sites/stores and claiming any compensation or rejecting the poles if not found according to specification. All charges consequent to rejection, rectification and replacement shall be borne by the supplier.

13. TOLERANCE :

The following tolerances shall be allowed :

i) Over all length of PCC poles.±15 mm ii) Top and bottom dimension. (Breadth and depth of PCC poles) ± 3 mm iii) Clear concrete cover over HT steel wires (Average of

measurements at three sections). - 2 mm

28

iv) Uprightness or straightness of the PCC poles. 0.5 % v) Internal dia of eye hook + 20 mm and – 5 mm vi) Dia of holes ± 1 mm vii) Diameter of HT wires as per IS: 280/1979 ± 0.05 % viii) Diameter of GI wire as per IS:280/1979 ± 2.5% ix) Diameter of MS rod for eye hook as per 1786/1966 ± 4% Higher dimensions of poles shall attract no penalty / deduction as it will not be considered as deviation.


The tenderer shall furnish the guaranteed technical particulars of the PCC poles as required in the schedule-A by mentioning specific figures therein. Any item of the GTP left unfilled or simply written as per ISS etc. shall be considered as incomplete GTP 15. TRANPORTATION ARRANGEMENTS :


The tenderers should also furnish the particulars of transportation vehicles owned by them..

16. CRITERIA FOR ACCEPTANCE:

The inspected PCC poles should be strictly in accordance to the GTP of the specification otherwise the material shall be treated as rejected and shall not be accepted. However, the poles with some minor deviations may be accepted with deductions as per rates prescribed and in force.

Higher dimensions of poles shall not attract any penalty / deduction, as it will not be considered as deviation.

29

SCHEDULE-A

GUARANTEED TECHNICAL AND OTHER PARTICULARS OF 9 METREPCC POLES HAVING WORKING LOAD 200 KG. WITH FACTOR OF SAFETY 2.5 S.No. Particulars Requirement as per GTP 1 MANUFACTURER’S NAME 2 OFFICE ADDRESS 3 WORKS ADDRESS



5 OVER ALL LENGTH 9 metre 6 PLANTING DEPTH 1.5metre 7 TOP DIMENSIONSIN MM 145 x114 mm 8 BOTTOM DIMENSIONS IN MM 300 x114 mm 9 APPROXIMATE WEIGHT 545 Kg. 10 WORKING LOAD 200 Kg. 11 FACTOR OF SAFETY (F.O.S.) 2.5 12 NO. & DIA OF HT WIRE (TENSIONED) 16( 4 mm dia) 13 CONFIGURATION OF HT WIRE As per approved drawings 14 POSITION OF EARTH WIRE LENGTH

AND SIZE OF WIRE G.I. wire of 4 mm diahaving continuous length with a projection of 100 mm at 250 mm from top and 150 mm from below ground level.


2 Nos.of Eye hook of 12 mm dia M.S. round having internal dia of 40 mm at 2.25metre from top and 1.8metre from bottom


8 Nos. of rings of 4 mm dia HT wires on top and 8 Nos. of rings on bottom (both ends) with minimum inter spacing of 20 mm.

17 CONCRETE COVER 30 mm 18 MARKING ON THE POLES Marking should be engraved on transverse

face19 BLACK STRIP A strip of 30-40 mm shall be painted with

oil paint of Blackcolour, on one side(transverse face) of the pole at a planting depth of 1.5 Metre from bottom.


21 ULTIMATE TENSILE STRENTH 17500 Kg./ sq.cm22 CONCRETE QUANTITY PER POLE 0.228M3

23 CONCRETE GRADE M-45 Note:- Max. tension in wire should not exceed 80% of its ultimate tensile strength.

Signature of the Bidder

Name Designation

Common authorized seal of bidder

30

TECHNICAL SPECIFICATION FOR SUPPLY OF 8 M. LONG PCC POLES OF 200 KG WORKING LOAD WITH FACTOR OF SAFTY 2.5, .

1. SCOPE :

This specification covers the design, manufacture, inspection and testing of finished 8 Metre long- 200 Kg. rectangular shaped, solid prestressed cement Concrete poles, witnessing of tests before despatch and its transportation from the firm’s works to consignee’s head quarters. These poles are to be used for erection of 11 KV & LT over head lines.


I. Peak ambient temperature 50 Degree C II. Maximum average ambient temperature 40 Degree C

III. Maximum temperature attainable 60 Degree C IV. Maximum relative humidity 100 %V. Minimum relative humidity 50 %VI. Average number of thunder storm days per annum 40VII. Average number of rainy days per annum 100

VIII. Average annual rainfall 10-100 cm IX. Maximum wind pressure 100 Kg/sq.m X. Altitudes not exceeding 1000 mtrs.



1 REC manual No.13/1977

(part-I)

Manual on manufacturing of solid poles part-I design aspects.




4 IS:1678/1978 (Latest amended) Specification for PCC poles for overhead power traction & telecommunication lines.


31

6 IS:7321/1974 (Latest amended) Code of practice for selection handling and erection of concrete poles for overhead power and telecommunication lines.




4. MATERIAL




(iii) WATER :Water should be free from chlorides, sulphates, other salts and organic matter. Potable water is generally suitable.

(iv) ADMIXTURES : These admixtures should not contain calcium chloride or other chlorides and salts which are likely to promote corrosion of pre-stressing steel.


(vi) CONCRETE MIX : The concrete mix. shall be designed to the requirements laid down for controlled concrete (also called design requirement laid down/mix. concrete) in IS:1343/1980 (Code of practice for prestressed concrete) and IS:456/1978 (code of practice for plain and reinforced concrete) subject to the following special conditions :


b) The mix. should contain at least 380 Kg. cement per cubic metre of concrete.

c) The concrete strength at transfer should be at least 210Kg. / cm.2

32

d) The mix. should contain as low water content as is consistent with adequate workability. If it becomes necessary to add water to increase the workability the cement content should also be raised in such a way that the original value of water cement ratio is maintained.

(vii) REINFORCEMENT : The reinforcing bars and wires used for manufacturing of prestressed cement concrete poles shall conform to the following Indian standards.


(viii) WELDING AND LAPPING OF STEEL: The high tensile steel wire shall be

continuous over the entire length of the tendon. Welding shall not be allowed in any case. However, jointing or coupling be permitted provided the strength of the joint or coupling is not less than the strength of each individual wire.



a) The poles shall be planted directly in the ground with a planting depth of 1.5 metres. b) The working load on the poles shall be 200 Kg. applied at 0.6 Mtr. from top. c) The factor of safety shall not be less then 2.5. d) The average permanent load should be 40% of the working load. e) The Factor of safety against first crack load shall be 1.0 f) The ultimate moment capacity in the longitudinal direction should be atleast



ensured in the design i.e. : 420x0.5 = 210 KG./SQ.MM. i) The concrete cover, measured from outside of prestressing tendon shall be

20 mm. j) At the design value, of first crack load the modules of rupture shall not exceed 55.2

Kg./cm for M-42 concrete. 6. OPTIMUM DESIGN DIMENSIONS :

Bottom depth. : 290 mm Top depth. : 145 mm Breadth. : 90mm No. of tensioned wire : 12Nos. wires of 4 mm dia. No. of untensioned wire : 2Nos. wires of 4 mm dia Length. of untensioned wire : 3.95 metre from bottom end Configuration type. : JVVNL specification

If any practical difficulty is experienced in using part length of untensioned wires, full length wires may be used but the tension in these wires, should not exceed 5% of their Ultimate tensile strength.

33

7. OTHER TECHNICAL REQUIREMENT : A) EARTHING : Earthing shall be provided, by having continuous length of 4 mm dia G.I.wire embeded in concrete during manufacture and the ends of G.I. wire left projected from the transverse face of the poles to a length of 100 mm at 250 mm from top and 150 mm below ground level (Planting depth to be 1.5 M) The tolerance of 25 mm shall be allowed in position of earth wire. The earth wire shall not be allowed to entangle with prestressing wires.

B) EYE HOOKS : The eye hooks shall be provided on the middle of transverse face of the pole as per IS: 7321/1974 at a distance of about 1.70 metre from top and about 1.60 metre from the bottom, to facilitate the handling. The eye hooks shall be of 10 mm dia MS round and shall have an internal dia of 40 mm. The tolerance of minus 5 mm and plus 20mm in internal dia of eye hooks shall be allowed. the eye hooks in question shall be securely embeded in the pole to ensure safe handling/ loading unloading of poles.

C) REINFORCEMENT : The poles offered should have 8 Nos. rings of 4 mm dia HT wires rings on top side of the pole and 8 Nos. rings of 4 mm dia HT wire rings on the bottom side of the pole thus total HT wire rings should be 16 in all or 4 Nos. of 6 mm dia MS round rings on top side and 4 Nos. of 6 mm dia MS round rings on bottom side are to be provided. The minimum inter spacing of 20 mm in case of 4 mm dia HT wire rings and 30 mm in case of 6 mm dia MS round rings is to be maintained. These rings should be complete and rectangular in shape with minimum over lapping of 20 mm. No rings are to be bunched together.


8. WORKMANSHIP :

(i) All materials used in the finished PCC poles and workmanship shall be of required quality. No deviation with technical particulars required as per this tender specification shall be allowed. (ii) Apart from the requirements regarding the design, material, process of manufacture, dimensions shape, workmanship finishing etc., acceptability of PCC poles shall be determined by the results of various tests to evaluate their properties as stipulated in the relevant IS/specification.

9. DRAWINGS :

The tenderer shall furnish alongwith the tender the detailed dimensional drawing based on the JVVNL drawing (enclosed) showing the plan, elevation and end cross sectional views clearly indicating the configuration of HT wire size and No. of HT wire, eye -hook's position & projection of earth wire marking & reinforcement. The drawing is also required to be got approved before commencement of supply.

10. MARKING :

34

The poles shall be clearly & indelibly marked with the following particulars by engraving properly at a height of 3 metres from the bottom end so as to be easily readable after erection. Marking should not be painted.

1. S.No. of pole.

. 2. Date, month and year of manufacturing

3. Name/mark of manufacturer.

It should be distinct and should not resemble with mark of other manufacturers andif it resembles with marking of other manufacturers then you should change your marking.

4. Length and working load 8 M/200 Kg.

5. IPDS/TN/ JVVNL

RED STRIP PAINTING: A strip of 30-40 mm shall be painted on one side ( transverse face) of the pole at a planting depth (1.5 Metre from bottom) with oil paint of red colour in such a manner that the red strip shall be visible above the ground. Poles without marking of red strip will not be accepted and considered as rejected.


The inspection and testing shall be carried out at supplier’s works as per relevant ISS: GTP/ Spec. before dispatch in accordance with the clause No.1.27 of GCC

The supplier shall incorporate the following certificate in his offer letter which should indicate Sr. No. & total No. of poles casted on different dates, as offered for the present inspection:

a) That all the PCC poles included in the lot under the present inspection conform to the design, strength and workmanship required as per the purchase order, GTP of the specification and contract drawing under the TN.





35

The supplier shall arrange the required number of PCC Poles out of the offered lots as per the sampling plan under this specification for witnessing the various tests by Inspecting Officer. The poles so tested in presence of the Inspecting Officer shall be preserved for atleast 30 days from the date of inspection for subsequent checking by any other representative for the purchaser if needed. The supplier shall intimate in writing name and address of purchaser of these tested poles.




c) Details of all meters/ instruments /equipments to be used in the process of checking and testing of the material alongwith the details for their last calibration (original) certificates of calibration indicating that calibration had been done to full range on all the scales to verify that the last calibration and sealing was got done from the manufacturer or an independent test house approved by NABL /Government within one year prior to the date of inspection.


A. SAMPLING:

b) In a consignment, 500 poles or a part thereof of the same overall length, same dimensions and belonging to the same batch of manufacturer shall be grouped together to constitute a lot. For ascertaining the conformity of the materials in the lot to the requirements of the specification, samples shall be tested from each lot separately. The number of poles to be selected from the lot shall depend on the size of the lot and shall be according to table as under:-


Size of lot or sub-lot

in numbers (N)

Dimensional requirement No.of poles for transverse

strength test (n)

sample size (n)

Permissible No. of defective samples

1 2 3 4 Upto 100 10 1 1

101 to 200 15 1 3 201 to 300 20 2 4 301 to 500 30 3 5

The minimum size of lot which can be offered for inspection is 300 Nos. of pole except in case of last lot which may be for left out balance quantity. Lot size once

36

offered for inspection, can not be reduced subsequently under the re-inspection, unless re-inspection charges for each lot/ sub-lot out of the original lot is deposited.



d) PCC poles, in every lot/sub lot sampled for transverse load strength test shall satisfy the requirement of the test. Initially, selection of sample and inspection and testing of poles will be undertaken as usual as is being done according to IS:1678/1998 and IS:2905/1989 with latest amendments. In case the samples selected satisfied the dimensional requirements and also withstand transverse load test, the lot stands cleared.

In case of one or more poles fail during transverse load test, then twice the number of originally tested shall be selected from those already selected and subjected to the tests. If these poles withstand the transverse load test the entire lot will be deemed to have passed the tests and will be cleared, but if one or more pole fails during double sampling, then leaving aside the sub-lots for which double sampling was done and where samples could not withstand transverse load test, the remaining sub-lots representing poles from which have withstood transverse load test will be accepted provided they satisfy clause No. 9.3.2 of IS:1678/1978. However, the destruction test from the sub-lots will be done by the inspecting officer on the poles on which transverse load was performed and the acceptance of these sub-lots will be on the basis of the test results observed by the inspecting officer during destruction test on the respective representative poles.

e) All the poles subject to transverse load strength test shall be preserved for atleast 30 days from the date of inspection for any subsequent checking by any other representative of the purchaser, if required. These poles shall not be dispatched /supplied to the purchaser.




37


B) INSPECTION :

Inspection shall comprise of : a) Verification of offered quantity as per packing list. b) Visual inspection for shape, workmanship and finishing of the PCC poles. c) Checking of dimensions as per the ISS/GTP/ Spec. d) Verification of marking and red/ black strip as per GTP.

C) WITNESS OF TRANSVERSE LOAD TESTS :

v) On PCC poles selected for transverse load strength test as per sampling

plan. vi) On one PCC pole from every lot/sub lot be destructed to ascertain the No.,


As per provision of Clause No.6.2.5 "load measurement" of IS: 2905/1989. The dynamometer or any other satisfactory method of load measurement shall be calibrated at regular intervals ( Not more than one year) and capable of measuring load to the accuracy of 50 N may be adopted.

The transverse strength test on poles shall be conducted in accordance with IS:2905. A prestressed concrete pole shall be deemed not to have passed the test if cracks wider than 0.1 mm appear at a stage prior to the application of the designed transverse load at first crack and the observed ultimate transverse load is less than the designed ultimate transverse load.

12. TEST AT SITE :

The purchaser reserves the right to get the material tested after receipt of inspected poles at sites/ stores and claiming any compensation or rejecting the poles if not found according to specification. All charges consequent to rejection, rectification and replacement shall be borne by the supplier.

38

13. TOLERANCE : The following tolerances shall be allowed :

i) Over all length of PCC poles. ±15 mm ii) Top and bottom dimension. (Breadth and depth of PCC poles) ± 3 mm iii) Clear concrete cover over HT steel wires (Average of

measurements at three sections). - 2 mm iv) Uprightness or straightness of the PCC poles 0.5 % v) Internal dia of eye hook + 20 mm and – 5 mm vi) Dia of holes ± 1 mm vii) Diameter of HT wires as per IS: 280/1979 ± 0.05 % viii) Diameter of GI wire as per IS:280/1979 ± 2.5% ix) Diameter of MS rod for eye hook as per 1786/1966 ± 4%

Higher dimensions of poles shall attract no penalty / deduction as it will not be considered as deviation.


The tenderer shall furnish the guaranteed technical particulars of the PCC poles as required in the schedule-A by mentioning specific figures therein. Any item of the GTP left unfilled or simply written as per ISS etc. shall be considered as incomplete GTP and such tender is liable to be rejected.

15. TRANPORTATION ARRANGEMENTS :


The tenderers should also furnish the particulars of transportation vehicles owned by them. 16. CRITERIA FOR ACCEPTANCE:

The inspected PCC poles should be strictly in accordance to the GTP of the specification otherwise the material shall be treated as rejected and shall not be accepted. However, the poles with some minor deviations may be accepted with deductions as per rates prescribed and in force. Higher dimensions of poles shall not attract any penalty / deduction, as it will not be considered as deviation.

39

SCHEDULE-A

GUARANTEED TECHNICAL AND OTHER PARTICULARS(GTP) OF 8 Metre PCC POLES HAVING WORKING LOAD 200 KG. WITH FACTOR OF SAFETY 2.5

S.No. Particulars Requirement as per GTP 1 MANUFACTURER’S NAME 2 OFFICE ADDRESS 3 WORKS ADDRESS



5 OVER ALL LENGTH 8 Metre 6 PLANTING DEPTH 1.5 metre 7 TOP DIMENSIONS IN MM 145 x 90 mm 8 BOTTOM DIMENSIONS IN MM 290 x 90 mm 9 APPROXIMATE WEIGHT 380 Kg. 10 WORKING LOAD 200 Kg. 11 FACTOR OF SAFETY (F.O.S.) 2.5 12 NO. & DIA OF HT WIRE

(TENSIONED) 12( 4 mm dia)

13 NO. & DIA OF HT WIRE (UNTENSIONED)

2( 4 mm dia) of length 3.95 mtr. each

14 CONFIGURATION OF HT WIRE As per approved drawing 15 POSITION OF EARTH WIRE

LENGTH AND SIZE OF WIRE G.I. wire of 4 mm dia having continuous length with a projection of 100 mm at 250 mm from top and 150 mm from below ground level.


2 Nos. of Eye hook of 10 mm dia M.S. round having internal dia of 40 mm at 1.7 metre from topand 1.6 metre from bottom


8 Nos. of rings of 4 mm dia HT wires on top and 8 Nos. of rings on bottom (both ends) with minimuminter spacing of 20 mm.

18 CONCRETE COVER 20 mm 19 MARKING ON THE POLES Marking should be engraved on transverse face 20 RED STRIP A strip of 30-40 mm shall be painted with oil paint

of red colour, on one side (transverse face) of thepole at a planting depth of 1.5 Metre from bottom.


22 ULTIMATE TENSILE STRENTH 17500 Kg./ sq.cm23 CONCRETE QUANTITY PER

POLE 0.157M3

24 CONCRETE GRADE M-42

Note:- Max. tension in wire should not exceed 80% of its ultimate tensile strength.

Signature of the Bidder Name

Designation Common authorized seal of bidder

40

TECHCHNICAL SPECIFICATIONS FOR GALVANISED M.S FORGED PINS FOR 33 KV PIN INSULATORS (33 KV PINS)

1.0 SCOPE : 1.1 This specification covers the design, manufacture, inspection testing before dispatch and supply of Galvanised M.S. Forged Pins specified herein for their satisfactory operation in 33 KV Sub-Transmission lines in Rajasthan.

2.0 CLIMATIC CONDITIONS :

2.1 The pins shall be suitable for being installed directly in air with power conductors of 33 KV Double Circuit and Single Circuit Sub-transmission lines. They shall be therefore suitable for satisfactory operation under the tropical climatic conditions listed below :

i) Location in the state

ii) Maximum ambient Air Temperature (deg.C) 50

iii) Minimum Ambient Air Temperature (deg.C) (-) 2.5 Temperature (deg.C)

iv) Average daily Ambient Air Temperature (deg.C) 32.2

v) Maximum relative humidity (%) 100

vi) Minimum relative humidity (%) 50

vii) verage rainfall per annum (mm) 150-1000

viii) Number of rainy days per Annum 70

ix) Altitude above mean sea level (meters) 100-1000

x) Isoceraunic level (Days/Annum) 25(thunder strom)

xi) Maximum wind pressure (Kg/sq.m.) 195

xii) ismic level (Horizontal Acceleration) 0.08 g

3.0 PRINCIPAL PARAMETERS :

The 33 KV galvanised M.S.Forged Pins suitable for use with 33 KV Pin Insulators(Confirming to ISS:731:1971 with latest amendments if any) shall comply in all respects with the ISS:2486 (Part-I):1993 & ISS:2486(Part-2/1989) (with latest amendments if any).

41

3.1 DETAILS OF GALVANISED M.S.FORGED PINS :

3.1.1 The 33 KV Galvanised M.S. forged pins should be suitable to be used with 33 KV Pin Insulator respectively for a three phase, 33 KV Sub-transmission lines in a moderately polluted atmosphere.

3.2 DRAWINGS :

Detailed drawings must be furnished alongwith Bid. The drawing shall comply with

IS 2486(Part-I)/1993 & IS:2486 (Part_II)/1989 with latest amendment if any. The 33 KV Galvanised M.S.Forged Pins shall be suitable for use with 33 KV Pin Insulator (conforming to IS 731/1971 with latest amendment, if any) respectively.

4.1 GENERAL TECHNICAL REQUIREMENTS :

4.2 HEADS :

The head shall be of steel and shall be in accordance with Fig.1 of IS:2486 (Part-

2) / 1989 with latest amendments, if any. They shall screw into a thimble fixed in the pin hole of the insulators. The dimensions of the gauges for these heads are given in fig. 2 to 4 of aforesaid IS.

4.3 PINS :

The 33 KV galvanised M.S.Forged Pins suitable for use with 33 KV Pin Insulators

(Conforming to IS:731/1971 with latest amendments if any) shall comply in all respects with the IS: 2486 (Part-1)/1993 & IS:2486 (Part-2)/1989 with latest amendments if any. The dimensions of the line pins shall be as given in fig. 5 of the above mentioned ISS.

4.4 STALKS :

The stalk length of line pins shall be measured above the seating face of the collor

conforming to IS:2486 (Part-2)/1989. 4.5 SHANKS :

The shank length of the line pins shall be measured below the seating face of the

Collor & conforming to IS:2486 (Part-2)/1989. 4.6 GALVANISED M.S.FORGED PINS :

i) GALVANISATION :

All ferrous pins and nuts shall be hot dipped galvanised. The galvanisation shall

conform to IS: 2633/1986 with latest amendments and satisfy the requirements given in IS:4759/1984. The threads on the nuts & tapped holes shall be cutout after galvanising & shall be well oiled or greased. Spring washers shall be electro galvanised conforming to service grade No.4 of IS:1573/1986(latest amended).

42

ii) FAILING LOAD :

The 33 KV Pins shall be offered for minimum failing load of 10 KN.

iii) DIMENSIONS : The 33 KV Pins for supply under this specification shall be of small steel head as per figure No. 6 of IS:2486 (Part-2)/ 1989 and shall have the following dimensions.

For 33 KV : ---------------

a) Stalk length. : 230 mm b) Shank length. : 150 mmc) Hexagon nut : M24 as per IS:1363(Part-3) /1992d) Spring washer : Nominal size 24 as per IS:3063/1972.

4.6. THREADS :

Threads shall be as specified in IS:4218 (Part-2) /1976 and matching with 33 KV Pin Insulators conforming to IS:731/1971 (with latest amendments if any)

4.7 HEXAGON NUTS :

Hexagon Nuts of M-24 size shall conform to IS:1363(Part-3):1992 (latest

amended). 4.8 SPRING WASHERS :

Spring washers shall conform to IS:3063:1972 (Latest amended).

4.9 MATERIAL DESIGN AND WORKMANSHIP :

4.9.1 GENERAL :

i) All raw materials to be used in the manufacture of these pins shall be

subject to strict raw material quality control and to stage testing/quality control during manufacturing stage to ensure the quality of the final end product. Manufacturing shall conform to the best engineering practices adopted in the field of high voltage transmission. Bidders shall therefore offer pins as are guaranteed by them for satisfactory performance on 33 kV Sub-transmission Lines.

ii) The design, manufacturing, process and material control at

various stages be such as to give maximum working load, highest mobility, best resistance to corrosion, good finish, elimination of sharp edges and corners.

43

4.10 TESTS

4.10.1 TEST BEFORE DESPATCH: The 33 KV Galvanised M.S.Forged pins and accessories shall be subjected at maker's works before despatch, to the tests mentioned here-under as per IS: 2486(Part.1)/1993 (with latest amendments).

4.10.2 ROUTINE TESTS :

The following tests shall be conducted on each unit by the bidder at his works

as per relevant standard - IS:2486 (Part-1)/1993 (latest amended) :

a) Visual Examination ( Clause-8 ) 4.10.3 CCEPTANCE TESTS :

The following tests shall be conducted on samples taken at random from a lot as

per relevant standard, IS:2486 (Part-1)/1993 (latest amended) in presence of purchaser's representative :

a) Verification of dimensions (Clause 8 & 9.2.2 ) b) Galvanizing Test (Clause 9.4) c) Mechanical Tests (Clause 9.5)

5.0 TYPE TESTS

5.01 The bidder shall furnish valid and authenticated type test certificates from a

Govt. approved / Govt. recognized / NABL Accredited laboratory / ILAC i.e. International Laboratory Accredited Laboratory (in case of foreign laboratory) of similar rating and design of tendered material/ equipment. Such type test certificates should not be older than 05 years as on the date of bid opening. For this purpose date of conducting type test will be considered.

The type test certificate by in house laboratory of tendering firm even if it is a Govt. approved / Govt. recognized / NABL accredited / ILAC accredited, shall not be accepted, in case of their own tender. This will not apply if tendering firm is Govt. company / public Sector undertaking.

5.2 The bidder should furnish documentary evidence in support of the laboratory whose type test have been furnished, that the said laboratory is a Govt. / a Govt. approved / a Govt. recognized / NABL accredited laboratory / ILAC accredited (in case of foreign laboratory).

5.3 The type test certificates shall be furnished either in original or copy duly attested by notary.

44

5.4 The following shall constitute the type tests which are to be conducted on atleast three units of each rating as per relevant standard IS:2486 (Part-1)/1993 (Latest amended) :-

a) Freedom from defects (Clause 5 & 6). b) Verification of dimensions (Clause 8 & 9.2.2) c) Galvanizing Test (Clause 9.4) d) Mechanical Tests (Clause 9.5) e) Chemical Composition Test (Clause 9.6)

5.3 SAMPLING : As per IS:2486 (Part-1)/1993 (latest amended)

5.4 TOLERANCE ON TEST RESULTS : As per IS:2486(Part-1)/1993 & IS:2486 (Part-2)/1989(latest amended).

5.5 TESTING FACILITIES :

The bidder must indicate clearly about the various testing facilities for type test

as well as for routine/sample tests as per relevant ISS is respect of M.S.Forged Pins as are available at their works. In case no testing facilities are available at the bidder’s works particulars of the place where such testing is proposed to be conducted during the course of inspection must be indicated.

6.0 INSPECTION

All the tests (as mentioned at Clause 4.10) and Inspection shall be made at the place of manufacturer unless otherwise especially agreed upon by the bidder and purchaser at the time of purchase. The bidder shall afford the inspection officer(s) representing the purchaser all reasonable facilities without charges, to satisfy him that the material is being furnished in accordance with this specification. The purchaser has the right to have the tests carried out at his own cost by an independent agency whenever there is a dispute regarding the quality of supply.

The Inspection may be carried out by the purchaser at any stage of

manufacture/ before despatch as per relevant standard.

Inspection and acceptance of any material under the specification by the purchaser, shall not relieve the bidder of his obligation of furnishing material in accordance with the specification and shall not prevent subsequent rejection if the material is found to be defective. The Bidder shall keep the purchaser informed in advance, about manufacturing programme so that arrangements can be made for inspection.

The purchaser reserves the right to insist for witnessing the acceptance/ routine

testings of the bought out items.

The Bidder shall give 15 days( for local supplies) / 30 days ( in case of foreign bidder) advance intimation to enable the purchaser to depute his representative for witnessing the acceptance and routine tests. The inspection charges would be to the purchaser's account.

45

7.1 PACKING & FORWARDING :

i) All 33 KV Galvanised M.S.Forged pins shall be packed in double bags, one HDP bag (inner) and one gunny bag (outer) or in double gunny bag. The gross weight of each packing shall not normally exceed 50 Kg.

ii) The packing shall be of sufficient strength to withstand rough

handling during transit, storage at site and subsequent handling in the field. 8.0 TEST CHECKING OF MATERIAL AT STORES

8.1 The material received in the stores of the NIGAM shall be subjected to the test checking at stores before final acceptance of the material, the procedure for the same shall be as under :

8.2 SAMPLING

One sample out of each sub-lot / lot of 1000 Nos. or part thereof from each

inspected lot received in stores shall be selected for test checking of material and shall be got tested. The selection of sample from the material received at stores shall be done as soon as material is received in stores without the presence of the representative of the supplier. However, testing of sample(s) at CTL shall be carried out in the presence of representative of the supplier after identification / confirmation by him that sample so selected belongs to them. In case the supplier disputes that the selected samples does not pertain to them, then fresh sample shall be selected in the presence of the representative of the supplier and test(s) be carried out.

83 TESTS

The following tests shall be carried out on the above items :

a) Visual Examination, Verification of Dimension, weight and marking b) Mechanical Test. c) Galvanisation (Uniformity) Test.

Only those test shall be conducted at CTL for which facility with CTL is available.

8.4 Test of the material shall be got done at the test laboratory of the NIGAM i.e CTL, Jaipur in the presence of representative of supplier. For witnessing of the testing, clear 7 (seven) days notice shall be given to the supplier by fax/ speed post stating date, time & place where the test is to be conducted. In case the supplier do not attend for witnessing the testing, the testing shall be proceeded and completed and action be taken as per the contract.

8.5 The witnessing officers of the NIGAM or as designated by the purchaser shall send copies of test reports to the purchaser, consignees and the supplier.

46

9.0 CRITERIA FOR ACCEPTANCE

9.1 Visual Examination, Verification of Dimension, weight and marking .

As per specification/ ISS 9.2 Mechanical test.

In case of failure of sample in Mechanical Test, the material contained in

the lot / sub-lot to which the sample belongs, shall be rejected. The rejected material shall have to be replaced by the supplier free of cost.

9.3 Galvanisation (Uniformity) Test.

9.3.1 The sample(s) shall be first tested for (n-2) number of dips where (n) is specified number of dips in the contract. If the sample(s) does not pass the uniformity of Galvanisation Test for (n-2) dips, the material shall be rejected and the material relating to relevant lot / sub-lot to which sample(s) pertains shall have to be replaced by the supplier free of cost.

9.3.2 If the sample has passed the uniformity of Galvanisation Test for (n-2) dips, then it shall be tested for (n-1) dips. If the sample has not passed the uniformity of Galvanisation Test with (n-1) dips, then material pertaining to relevant lot / sub-lot shall be accepted with a deduction @ 10% of cost of material.

9.3.3 If the sample has passed the uniformity of Galvanisation Test with (n-1) dips, then sample shall be tested for last one dip of one minute to complete the test for `n' dips. If the sample does not pass the uniformity of Galvanisation Test with `n' dips, then the material pertaining to relevant lot/ sub-lot shall be accepted with a deduction @ 5% of cost of material.

9.3.4 If the sample(s) have passed the Test with number of dips as specified in the contract (n), then material pertaining to relevant lot / sub-lot shall be accepted.

10.0 TEST CHARGES :

All test charges incurred towards test checking of the material received in

our stores shall be borne by the NIGAM. 11.0 PAYMENT :

Payment shall be made only after receipt of successful test report from the CTL

on the samples selected from the material received at the stores. 12.0 IDENTIFICATION & MARKING :

12.1 Each 33 KV Pin shall be marked with the manufacturer's name or trade mark.

47

Prescribed technical specification for supply of

(Name of Material/Equipment/Machinery/T&P etc.)

GALVANISED M.S FORGED PINS FOR 33 KV PIN INSULATORS (33 KV PINS)

1.

Specification for Insulator fittings for overhead power lines with nominal voltage greater than 1000 V

IS:2486

General requirements and test

Dimensional Requirements

Part-1

Part-2

BS:3288(International Standard) IEC:120

2. Hexagonal Head Bolts, Screws and Nuts of Product grade C

IS:1363(Part.1)

Hexagonal Nuts (Size range M.5 to M.36)

IS:1363(Part.3)

3. Metric Screw Threads IS;4218

4. Dimensions for radii under the IS:4172

heads of bolts and screws.

5. 6.

Recommended practice for Hot dipgalvanising of Iron & Steel. Specification for Zinc

IS:2629

IS:209 7. Dimensions for nominal lengths IS:4206 and threads length for bolts,

screws and studs.

8. Schedules for wrought steel forgeneral engineering purpose Steel

IS:1570(Part.1)

specified by tensile and/or yield properties, 9.

10.

Specification for Carbon steelforgings for general engineering purposes. Method for determination of Zinc

IS:2004 IS:6745

coating on Zinc coated iron steel articles.

S.No. Technical specification Name of IS/other Other particulars towhich material/equipment/ standard specification if any.

Machinery/T&P shall conform to which material should

conform



conform

48

11. Electroplated coatings of zinc IS:1573

on iron and steel.

12. Introduction & general IS:1367 information for threaded (Part-1) fasteners.

13. Product grades & tolerances IS:1367

Part-II

14. Mechanical properties & test IS:1367 methods for Bolts screws and Part-III studs with full load ability.

15. Plain washers(Ist revision) IS:2016

16 Recommended practice for IS:2629

hot dip galvanised of iron & steel.

17. Methods of testing uniformity IS:2633

of coating of zinc coated article (IInd revision). 18. Spring Washer IS:3063/1972 (Latest amended)

Certified that we agree to all the aforesaid technical specification

(Signature)

Name & Designation

with seal of the bidder.

49

SCHEDULE- A

GUARANTEED TECHNICAL & OTHER PARTICULARS OF 33 KV GALVANISED M.S.FORGED PINS.

S.No Description Particulars 1) i) Manufacturer's Name & address

ii) Work’s address To be filled by bidder

2) Minimum failing load (KN) 10 KN 3) Standard specification to which the

material shall conform. IS: 2486 (Part-1)/1993 & IS:2486 (Part-2)/1989 with latest amendments if any.

4) Dimensions ( mm ):-

a) Total length. 380 mm b) Shank length. 150 mm c) Stalk length. 230 mm 5) Type of threads. As per IS 4218 (Part-2)/1976 6) Threads per inches. IS 4206 7 a) Type of Galvanisation. Hot dip b) Galvanisation shall conform to. As per IS: 2633/1986 with latest

amendments if any.8) Hexagon nut shall conform to M-24 IS: 1363(Part-3)/1992 9) Spring washer shall conform to Size 24 IS: 3063/1974 10) Electro-galvanization of spring

washer shall conform to. As per IS: 1573/1986

11) Packing details

a) Type of packing double bags, one HDPE bag (inner) and one gunny bag (outer) or in double gunny bag.

b) Weight of each pin 1800 gms.

c) No. of Pins in each packing. 25 Nos.

d) Weight of each package (kg) Less than 50 Kg.

12) Tolerance in dimensions, if any. As per IS: 2486 (Part-1)/1993 & IS: 2486 (Part-2)/1989 with latest amendments if any

13) Tolerance in weight. ±2% of 1800 gms.

14) ISI certification license number, if any.

To be filled by bidder

15) Any other relevant information the bidder would like to indicate.


16) Manufacturer's trade mark to be embossed on the pins.


17) Other details / informations. To be filled by bidder

Signature Name & Designation with seal of the firm

50

TECHNICAL SPECIFICATION AND OTHER REQUIREMENTS FOR GALVANISED M.S FORGED PINS FOR 11 KV PIN INSULATORS (11 KV PINS)

1.0 SCOPE : 1.1 This specification covers the design, manufacture, inspection and testing before despatch, supply of Galvanised M.S.Forged Pins specified herein for their satisfactory operation in 11 KV Sub-Transmission lines in Rajasthan.

1.2 The technical specifications, contained herein ,are for the guidance of the bidders. Any deviation from the Purchaser's specification will be considered on their relative merits in respect of performance, efficiency, durability and overall economy consistent with the requirements stipulated herein after. Such deviations shall be clearly entered by the bidders in the form as per schedule-VI of the specification.


2.1 The pins shall be suitable for being installed directly in air with power conductors of 11 KV Double Circuit and Single Circuit Sub-transmission lines. They shall be therefore suitable for satisfactory operation under the tropical climatic conditions listed below :

i) Location in the state

ii) Maximum ambient Air Temperature (deg.C) 50

iii) Minimum Ambient Air Temperature (deg.C) (-) 2.5 Temperature (deg.C)

iv) Average daily Ambient Air Temperature (deg.C) 32.2

v) Maximum relative humidity (%) 100

vi) Minimum relative humidity (%) 50

vii) ) Average rainfall per annum (mm) 150-1000

viii) Number of rainy days per Annum 70

ix) Altitude above mean sea level (meters) 100-1000

x) Isoceraunic level (Days/Annum) 25(thunder strom)

xi) Maximum wind pressure (Kg/sq.m.) 195

xii) ) Seismic level (Horizontal Acceleration) 0.08 g

51


The 11 KV galvanized M.S. Forged Pins suitable for use with 11 KV Pin Insulators(Confirming to ISS:731:1971 with latest amendments if any) shall comply in all respects with the ISS:2486 (Part-I):1993 & ISS:2486(Part-2/1989) (with latest amendments if any).

3.2 DETAILS OF GALVANISED M.S.FORGED PINS :

The 11 KV Galvanised M.S. forged pins should be suitable to be used with 11 KV

Pin Insulator respectively for a three phase, 11 KV Sub-transmission lines in a moderately polluted atmosphere.

3.3 DRAWINGS :

Detailed drawings must be furnished along with bid. The drawing shall comply

with IS 2486(Part-I)/1993 & IS:2486 (Part-II)/1989 with latest amendment if any. The 11 KV Galvanised M.S.Forged Pins shall be suitable for use with 11 KV Pin Insulator (confirming to IS 731/1971 with latest amendment, if any) respectively.


4.2 HEADS : The head shall be of steel and shall be in accordance with Fig.1 of IS:2486 (Part-2) / 1989 with latest amendments, if any. They shall screw into a thimble fixed in the pin hole of the insulators. The dimensions of the gauges for these heads are given in fig. 2 to 4 of aforesaid IS.

4.3 PINS :

The 11 KV Galvanized M.S. Forged Pins suitable for use with 11 KV Pin

Insulators (Conforming to IS:731/1971 with latest amendments if any) shall comply in all respects with the IS: 2486 (Part-1)/1993 & IS:2486 (Part-2)/1989 with latest amendments if any. The dimensions of the line pins shall be as given in fig. 5 of the above mentioned ISS.

4.4 STALKS :

The stalk length of line pins shall be measured above the seating face of the collor

conforming to IS:2486 (Part-2)/1989. 4.5 SHANKS :

The shank length of the line pins shall be measured below the seating face of the

Collor & conforming to IS:2486 (Part-2)/1989.

52

4.6 GALVANISED M.S.FORGED PINS :

i) GALVANISATION :

All ferrous pins and nuts shall be hot dipped galvanised. The galvanisation shall conform to IS: 2633/1986 with latest amendments and satisfy the requirements given in IS:4759/1984. The threads on the nuts & tapped holes shall be cutout after galvanising & shall be well oiled or greased. Spring washers shall be electro galvanised conforming to service grade No.4 of IS:1573/1986(latest amended).

ii) FAILING LOAD :

The 11 KV Pins shall be offered for minimum failing load of 5 KN.

iii) DIMENSIONS : The 11 KV Pins for supply under this specification shall be of

small steel head as per figure No. 5 of IS:2486 (Part-2)/ 1989 and shall have the following dimensions.

a) Stalk length. : 165 mm b) Shank length. : 150 mmc) Hexagon nut : M20 as per IS:1363(Part-3) /1992d) Spring washer : Nominal size 20 as per IS:3063/1972.

4.6. THREADS :

Threads shall be as specified in IS:4218 (Part-2) /1976 and matching with 11 KV Pin Insulators conforming to IS:731/1971 (with latest amendments if any)

4.7 HEXAGON NUTS :

Hexagon Nuts of M-20 size shall conform to IS:1363(Part-3):1992 (latest amended).

4.8 SPRING WASHERS :

Spring washers shall conform to IS:3063:1972 (Latest amended).

4.9 MATERIAL DESIGN AND WORKMANSHIP :

4.9.1 GENERAL :

i) All raw materials to be used in the manufacture of these pins shall be

subject to strict raw material quality control and to stage testing/quality control during manufacturing stage to ensure the quality of the final end product. Manufacturing shall conform to the best engineering practices adopted in the field of high voltage transmission. Bidders shall therefore offer pins

53

as are guaranteed by them for satisfactory performance on 11 kV Sub-transmission Lines.

ii) The design, manufacturing, process and material control at various stages be such as to give maximum working load, highest mobility, best resistance to corrosion, good finish, elimination of sharp edges and corners.

4.10 TESTS 4.10.1 TEST BEFORE DESPATCH: The 11 KV Galvanised M.S.Forged pins and accessories shall be subjected at maker's works before despatch, to the tests mentioned here-under as per IS: 2486(Part.1)/1993 (with latest amendments).


The following tests shall be conducted on each unit by the bidder at his works

as per relevant standard - IS:2486 (Part-1)/1993 (latest amended) :

a) Visual Examination ( Clause-8 ) 4.10.3 CCEPTANCE TESTS :

The following tests shall be conducted on samples taken at random from a lot as

per relevant standard, IS:2486 (Part-1)/1993 (latest amended) in presence of purchaser's representative :

a) Verification of dimensions (Clause 8 & 9.2.2 ) b) Galvanizing Test (Clause 9.4) c) Mechanical Tests (Clause 9.5)

5.0 TYPE TESTS 5.1 The bidder shall furnish valid and authenticated type test certificates from a Govt.

approved / Govt. recognized / NABL Accredited laboratory / ILAC i.e. International Laboratory Accredited Laboratory (in case of foreign laboratory) of similar rating and design of tendered material/ equipment. Such type test certificates should not be older than 3 years as on the date of bid opening. For this purpose date of conducting type test will be considered.



54

5.3 The type test certificates shall be furnished either in original or copy duly attested by

notary.

5.4 The following shall constitute the type tests which are to be conducted on atleast three units of each rating as per relevant standard IS:2486 (Part-1)/1993 (Latest amended) :-

a) Freedom from defects (Clause 5 & 6). b) Verification of dimensions (Clause 8 & 9.2.2) c) Galvanising Test (Clause 9.4) d) Mechanical Tests (Clause 9.5) e) Chemical Composition Test (Clause 9.6)

5.2 SAMPLING : As per IS:2486 (Part-1)/1993 (latest amended)

5.3 TOLERANCE ON TEST RESULTS : As per IS:2486(Part-1)/1993 & IS:2486 (Part-2)/1989(latest amended).


The bidder must indicate clearly about the various testing facilities for type test as

well as for routine/sample tests as per relevant ISS is respect of M.S.Forged Pins as are available at their works. In case no testing facilities are available at the bidder's works particulars of the place where such testing is proposed to be conducted during the course of inspection must be indicated.

7.0 INSPECTION


The Inspection may be carried out by the purchaser at any stage of manufacture/ before despatch as per relevant standard.

Inspection and acceptance of any material under the specification by the purchaser, shall not relieve the bidder of his obligation of furnishing material in accordance with the specification and shall not prevent subsequent rejection if the material is found to be defective. The Bidder shall keep the purchaser informed in advance, about manufacturing program so that arrangements can be made for inspection.

55

The purchaser reserves the right to insist for witnessing the acceptance/ routine testing of the bought out items.

The Bidder shall give 15 days( for local supplies) / 30 days ( in case of foreign bidder) advance intimation to enable the purchaser to depute his representative for witnessing the acceptance and routine tests. The inspection charges would be to the purchaser's account.

The bidders are required to indicate the delivery schedule in the schedule

attached with the Specification.

8.0 TEST CHECKING OF MATERIAL AT STORES 8.1 The material received in the stores of the NIGAM shall be subjected to the test checking at stores before final acceptance of the material, the procedure for the same shall be as under :

8.2 SAMPLING


inspected lot received in stores shall be selected for test checking of material and shall be got tested. The selection of sample from the material received at stores shall be done as soon as material is received in stores without the presence of the representative of the supplier. However, testing of sample(s) at CTL shall be carried out in the presence of representative of the supplier after identification / confirmation by him that sample so selected belongs to them. In case the supplier disputes that the selected samples does not pertain to them, then fresh sample shall be selected in the presence of the representative of the supplier and test(s) be carried out.

8.3 TESTS


a) Visual Examination, Verification of Dimension, weight and marking b) Mechanical Test. c) Galvanisation (Uniformity) Test.

8.4 Test of the material shall be got done at the test laboratory of the respective Discom in the presence of representative of supplier. For witnessing of the testing, clear 7 (seven) days notice shall be given to the supplier by fax/ speed post stating date, time & place where the test is to be conducted. In case the supplier do not attend for witnessing the testing, the testing shall be proceeded and completed and action be taken as per the contract.

8.5 The witnessing officers of the respective Discom or as designated by the purchaser shall send copies of test reports to the purchaser, consignees and the supplier and AO (CPC) of respective Discom.

8.6 Only those tests shall be conducted at CTL for which facility with CTL is available.

56


9.1 Visual Examination, Verification of Dimension, weight and marking . As per specification/ ISS

9.2 Mechanical test.

In case of failure of sample in Mechanical Test, the material contained in

the lot / sub-lot to which the sample belongs, shall be rejected. The rejected material shall have to be replaced by the supplier free of cost.


9.2.1 The sample(s) shall be first tested for (n-2) number of dips where (n) is specified number of dips in the contract. If the sample(s) does not pass the uniformity of Galvanisation Test for (n-2) dips, the material shall be rejected and the material relating to relevant lot / sub-lot to which sample(s) pertains shall have to be replaced by the supplier free of cost.




10.0 TEST CHARGES :

All test charges incurred towards test checking of the material received in

our stores shall be borne by the NIGAM.

11.0 PAYMENT :

Payment shall be made only after receipt of successful test report from the CTL of JVVNL on the samples selected from the material received at the stores.

12.0 IDENTIFICATION & MARKING :

Each 11 KV Pin shall be marked with the manufacturer's name or trade mark.

57

JAIPUR VIDYUT VITRAN NIGAM LIMITED

A Govt. of Rajasthan Undertaking



GALVANISED M.S FORGED PINS FOR 11 KV PIN INSULATORS (11KV PINS)

1.

Specification for Insulator fittings for overhead power lines with nominal voltage greater than 1000 V

IS:2486

General requirements and test

Dimensional Requirements

Part-1

Part-2

BS:3288(International Standard) IEC:120

2. Hexagonal Head Bolts, Screws and Nuts of Product grade C

IS:1363(Part.1)

Hexagonal Nuts (Size range M.5 to M.36)

IS:1363(Part.3)

3. Metric Screw Threads IS;4218

4. Dimensions for radii under the IS:4172

heads of bolts and screws.

5. 6.

Recommended practice for Hot dipgalvanising of Iron & Steel. Specification for Zinc

IS:2629

IS:209 7. Dimensions for nominal lengths IS:4206 and threads length for bolts,

screws and studs.

8. Schedules for wrought steel forgeneral engineering purpose. Steel

IS:1570(Part.1)

specified by tensile and/or yield properties, 9. Specification for Carbon steel IS:2004

forgings for general engineering purposes.



conform

58

10. Method for determination of Zinc IS:6745 coating on Zinc coated iron steel articles.

S.No. Technical specification

Name of IS/other

Other particulars

towhich material/equipment/ standard specification if any.


conform

11. Electroplated coatings of zinc IS:1573 on iron and steel.

12. Introduction & general IS:1367

information for threaded (Part-1) fasteners.

13. Product grades & tolerances IS:1367

Part-II

14. Mechanical properties & test IS:1367 methods for Bolts screws and Part-III studs with full load ability.

15. Plain washers(Ist revision) IS:2016

16. Methods of testing uniformity IS:2633 of coating of zinc coated article (IInd revision).


(Signature)

Name & Designation


59

SCHEDULE- (A)

GUARANTEED TECHNICAL & OTHER PARTICULARS OF 11 KV GALVANISED M.S.FORGED PINS.

S.N. Description 11 KV PINS 1. a) Manufacturer's Name & address. To be filled by bidder b) Work’s address To be filled by bidder 2. Minimum failing load (KN) 5 KN 3. Standard specification to which the

material shall conform. IS: 2486 (Part-1)/1993 & IS:

2486 (Part-2)/1989 with latest amendments if any.

4. Dimensions ( mm ):-

a) Total length. 315 mm b) Shank length. 150 mm c) Stalk length. 165 mm 5. Type of threads. As per IS 4218 (Part-

2)/1976 6. Threads per inches. IS 4206 7) a Type of Galvanisation. Hot dip b) Galvanisation shall conform to. As per IS: 2633/1986 with

latest amendments if any. 8. Hexagon nut shall conform to M-20 IS: 1363(Part-3)/1992 9. Spring washer shall conform to Size 20 IS: 3063/1974 10. Electro-galvanisation of spring washer

shall conform to. As per IS: 1573/1986

11. Packing details :-

a) Type of packing double bags, one HDP bag (inner) and one gunny bag(outer) or in double gunny bag

b) Weight of each pin (approx.) 925 gms.± 2% c) No. of Pins in each packing. 50 Nos. d) Weight of each package (kg) Less than 50 Kg. 12. Tolerance in dimensions,if any. As per IS: 2486 (Part-

1)/1993 & IS: 2486 (Part- 2)/1989 with latest amendments if any

13. Tolerance in Weight ± 2% of 925 gms 14. ISI certification license number, if any.

15. Any other relevant information the bider would like to indicate.

16. Manufacturer's trade mark to be embossed on the pins.


17. Other details/informations.

Signature Name & Designation with seal of the firm

60

TECHNICAL SPECIFICATION FOR GALVANISED M.S FORGED L.T.PINS AND HARDWARE FITTINGS FOR L.T. SHACKLE INSULATORS FOR USE ON L. T. DISTRIBUTION OVERHEAD POWER LINES

1.1 SCOPE :

1.2 This specification provides for the design, manufacture, inspection and testing before dispatch, and supply of Galvanised M.S. Forged L.T. Pins and Hardware fittings for L. T. Shackle Insulators specified herein for their satisfactory use & operation on various distribution overhead power lines of the State.

1.3 It is not the intent to specify completely herein all the details of the design and construction of equipment. However, the equipment shall conform in all respect to high standards of engineering, design and workmanship and shall be capable of performing in continuous commercial operation up to the bidder's guarantee, in a manner acceptable to the purchaser, who will interpret the meanings of drawings and specification and shall have the power to reject any work or material which in his judgment is not in accordance therewith. The offered equipment shall be complete with all components necessary for their effective and trouble free operation. Such components shall be deemed to be within the scope of bidder's supply irrespective of whether those are specifically brought out in this specification and / or the commercial order or not.


The pins and Hardware fittings shall be suitable for being installed directly in air with

power conductors L.T. single circuit/double circuit overhead distribution lines. These items, therefore, shall be suitable for satisfactory operation under the tropical climatic conditions listed below :

1. Location In the state of Rajasthan i) Maximum ambient air Temperature

(deg.C) 50

ii) Maximum Temperature attainable to an object exposed to sun (deg.C)

60

iii) Minimum Ambient air Temperature (deg.C)

(-) 5.0

iv) Average daily ambient air Temperature (deg.C)

40.0

v) Maximum relative humidity (%) 100 vi) Average rainfall per annum (mm) 100-1000 vii) Average Number of rainy days per

Annum 70

viii) Maximum altitude above mean sea level (meters)

1000

ix) Isoceraunic level (Days/Annum) 40 x) Maximum wind pressure (Kg/sq.m.) 195 xii) Seismic level 0.33 g


The material shall conform to the following specific parameters :

61

S.No. Item Specification 1. Type of Installation Outdoor 2. System Voltage 415 Volt(+10%, -15%) 3. System frequency 50 Hz, + 5% 4. Number of phases Three 5. System of earthing Solidly grounded.

4.0 DETAILS OF ITEMS :

The Galvanaised M.S. forged L.T. Pins & shackle insulator hardware fittings shall be suitable for use on single phase/three phase, 230/440 Volts overhead distribution lines in a moderately polluted atmosphere.


5.2 GALVANISED M.S. FORGED L.T. PINS :

5.2.1 The M.S.Forged L.T. Pins suitable for L.T.Pin insulators shall comply in all respect, herein otherwise stated, with figure 2 of IS:7935/1975 (latest amended). The Pins shall be of steel complying with class 2 of IS:2004/1970 (latest amended). The pins shall be of good finish, free from flaws and other defects. The finishng of collar shall be such that sharp angle between the collar and shank is avoided.

5.2.2 DIMENSIONS : The L.T. Pins for supply under this specification shall conform to figure 2 of IS:7935/1975 (latest amended) and shall have the following dimensions:

S.No. Item Dimensions 1. Length of Pin 260 mm i) Shank length 125 mm ii) Stalk length 135 mm 2. Thickness of stalk collar 5 mm 3. Diameter of stalk

i) at top 16 mm ii) at collar 32 mm 4. Diameter of shank 16 mm 5. Length of threads

i) on stalk 32 mm + 3 mm ii) on shank 75 mm 6. Thickness of nut(M-16)

i) Maximum 15.9 mm ii) Minimum 14.1 mm 7. Spring washer thickness(M-16) 3.5 mm + 0.2 mm 8. Weight of L.T.Pin (Approx.) 0.425 Kg.± 2% Tolerence

5.2.3 THREADS : Threads of L.T. pins shall be matching with L.T. Pin Insulators conforming to IS:1445/1977 ( latest amended) and shall be checked by means of gauges.

62

5.2.4 HEXAGONAL NUTS : Hexagonal Nuts of M-16 size shall be used & shall conform to IS:1363(Part-3):1992 (latest amended). The nuts shall be made of material conforming to class 4.8 of IS:1367 (Latest amended) with regard to its mechanical properties. The thickness of the hexagon nuts shall be in accordance with IS:1363 (Pt-3)/1984 (Latest amended). The screw threads on the shank and the nut shall be as prescribed in IS:4218 (Pt-6)/1978 (Latest amended).

5.2.5 SPRING WASHERS : Spring washers of 3.5 mm thickness of M-16 size shall be used which should conform to IS:3063:1994 (Latest amended).

5.2.6 FAILING LOAD : The minimum failing load of L.T. Pins shall be 2.0 KN.

5.2.7 GALVANISATION: The L.T.Pins shall be hot dip galvanised. The galvanisation of Pins shall conform to IS:2633/1986 (latest amended). The threads of nuts shall be cut after galvanisation and shall be well oiled or greased. Small parts like nuts and spring washers etc. may be electro-galvanised in accordance with IS:1573/1986 (latest amended).

5.2 GALVANISED HARDWARE FITTINGS FOR L.T. SHACKLE INSULATORS:

5.2.1 The hardware fittings for L.T. Shackle Insulators shall comply in all respects, herein otherwise stated, with fig.3, type-1 of IS:7935/1975 (latest amended). The hardware fittings assembly shall comprise the following:

i) A pair of mild steel straps, ii) Two numbers of mild steel bolts with

hexagonal head, iii) Two numbers of mild steel nuts of hexagonal

head to suit bolts under item (ii) above & iv) Two numbers suitable washers.

5.2.2 DIMENSIONS: The dimensions of hardware fittings for L.T. shackle insulators for supply under this specification shall conform to figure 3, type 1 of IS:7935/1975 (latest amended) and shall have the following dimensions:

S.No. Item Dimensions i) Length of straps 185 mm ii) Width of straps 30 mm iii) Thickness of straps 3 mm iv) Diameter of holes at the end of straps 14 mm v) Dia. of bolts 12 mm vi) Length of bolts 115 mm vii) Dia.of bolt head 17 mm viii) Thickness of bolt head.(M-12)

a Nominal 7.5 mm b Maximum 7.95 mm c Minimum 7.05 mm

ix Thickness of nuts

a Maximum 12.2 mm

63

b Minimum 10.4 mm x Shape of bolt head& nuts Hexagonal

xi Length of threaded portion of bolts. 65 mm xii Thickness of galvanized spring washer

(M-12) 3 mm + 0.15 MM

xiii Weight of complete hardware fitting set.(approx.)

0.475 Kgs.± 2% Tolerence

5.2.3 HEXAGONAL NUTS : Hexagonal Nuts of M-12 size shall be used & shall conform to IS:1363(Part-3):1992 (latest amended). The nuts shall be made of material conforming to class 4.8 of IS:1367 (Latest amended) with regard to its mechanical properties. The thickness of the hexagon nuts shall be in accordance with IS:1363 (Pt-3)/1984 (Latest amended). The screw threads on the shank and the nut shall be as prescribed in IS:4218 (Pt-6)/1978 (Latest amended).

5.2.4 SPRING WASHERS : Spring washers of 3.0 mm thickness of M-12 size shall be used which should conform to IS:3063:1994 (Latest amended).

5.2.5 Galvanisation: The Hardware fittings shall be hot dip galvanised. The galvanisation of Hardware fittings shall conform to IS:2633/1972 (latest amended). The threads of nuts and tapped holes shall be cut after galvanisation and shall be well oiled or greased. Small parts like nuts and spring washers etc. may be electro-galvanised in accordance with IS:1573/1970 (latest amended)


5.3.1 The pins and hardware fittings for shackle insulators shall be marked with the manufacturer's name or trade mark.

5.3.2 The package containing the insulator fittings may also be marked with the ISI certification mark if available.

6.1 TESTS :

6.2 TEST BEFORE DESPATCH: The Galvanised M.S.Forged L.T. pins and Hardware fittings for L.T.shackle insulators shall be subjected at manufacturer’s works before despatch, to the tests mentioned here-under as per IS: 7935/1975 (latest amended).


The following tests shall be conducted on each unit by the bidder at his works as per relevant standard - IS:7935/1975 (latest amended) :

a) Visual Examination ( Clause-4.4)

64

6.2.2 ACCEPTANCE TESTS :

The following tests shall be conducted on samples taken at random from a lot as per relevant standard, IS:7935/1975 (latest amended) in presence of purchaser's representative :

a) Checking of threads on heads (Clause 4.6 ) b) Galvanizing / Electroplating test (Clause 4.7) c) Verification of dimensions (Clause 4.5) d) Mechanical Strength Test (Clause 4.8)

6.3 TYPE TESTS

a) The bidder shall furnish valid and authenticated type test certificate from a Govt. approved/ a Govt. recognized/ NABL accredited laboratory/ ILAC i.e. International Laboratory Accredited laboratory / ILAC i.e International Laboratory Accrediation Cooperation ( In case of foreign laboratory) . Such type test certificates should not be older than five years as on the date of bid opening. For this purpose date of conduction Type Test(s) will be considered.

b) The type test certificates by in house laboratory of biding firm even if it is a Govt approved/ Govt recognized/ NABL accredited/ ILAC accredited,shall not be accepted, in case of their own bid. This will not apply if biding firm is Govt. Company/ Public Sector Undertaking.

c) The bidder should furnish documentary evidence in support of the laboratory whose type test have been furnished, that the said laboratory is a Govt/ a Govt. approved/ a Govt. recognized/ NABL accredited laboratory/ ILAC accredited ( in case of foreign laboratory)

d) The type test certificates shall be furnished either in original or duly attested by notary.

e) The bids of only those bidders shall be considered to be meeting the type test criteria who furnishes complete type test certificates with the bid as per above provision.

6.3.1 The following shall constitute the type tests which are to be conducted on at least

three units of each rating as per standard IS:7935/1975 (Latest amended) and other relevant standards :-

a) Visual examination test (Clause 4.4). b) Verification of dimensions (Clause 4.5) c) Checking of threads on heads ( clause 4.6) d) Galvanising/electroplating test (Clause 4.7) e) Mechanical strength tests (Clause 4.8) (for pins only)

6.3.2 However, the purchaser reserves the right to demand repetition of some or all the type tests in presence of purchaser's representative. For this purpose, the bidder should indicate unit rates for carrying out such type tests. These test charges shall not be taken into consideration for bid evaluation.

6.4 SAMPLING : As per IS:7935/1975 (latest amended)

65

6.5 TOLERANCE ON TEST RESULTS : The tolerance for dimensions when not indicated in the drawing i.e. fig. 2 & 3 of IS:7935/1975 (Latest amended) for L.T.Pins & Hardware Fittings for L.T.Shackle Insulators, shall be ± 5% except on collar thickness of L.T.pins for which tolerance is allowed upto 2 mm on plus side and 0.5 mm on minus side.

6.6 TEST AT SITE:

The purchaser reserves the right to conduct all tests on Galvanised M.S.Forged

L.T. Pins & Hardware fittings after arrival at site / store and the contractor shall guarantee test certificate figures under actual service conditions.

6.7 TESTING FACILITIES:

The bidder must indicate clearly about the various testing facilities for the acceptance

tests as well as routine tests as per relevant ISS as are available at their works. In case no testing facilities are available at the bidder's works, particulars of the place where such testing is proposed to be conducted during the course of inspection must be indicated.

7.1 INSPECTION

7.2 All the tests as mentioned at Clause 6.1.1 & 6.1.2 for pre-despatch inspection shall be made at the place of manufacturer unless otherwise especially agreed upon by the bidder and purchaser at the time of purchase. The bidder shall afford the inspection officer(s) representing the purchaser all reasonable facilities without charges, to satisfy him that the material is being furnished in accordance with this specification. The purchaser has the right to have the tests carried out at his own cost by an independent agency whenever there is a dispute regarding the quality of supply.

7.3 The Inspection may also be carried out by the purchaser at any stage of manufacture/ before despatch as per relevant standard.

7.4 Inspection and acceptance of any material under the specification by the purchaser, shall not relieve the bidder of his obligation of furnishing material in accordance with the specification and shall not prevent subsequent rejection if the material is found to be defective. The Bidder shall keep the purchaser informed in advance, about manufacturing programme so that arrangements can be made for inspection.

7.5 The purchaser reserves the right to insist for witnessing the acceptance/ routine testings of the bought out items.

7.6 The Bidder shall give 15 days advance intimation to enable the purchaser to depute his representative for witnessing the acceptance and routine tests. The inspection charges would be to the purchaser's account.

8.1 DOCUMENTATION :

66

8.2 The Bidder shall furnish full description and illustrated catalogues of material offered alongwith the bid.

8.3 The Bidder shall also furnish alongwith the bid the outline drawing of L.T. Pins & hardware fittings as per reference fig. of relevant ISS.

8.4 TEST REPORTS :

8.4.1 Two sets of type test reports duly approved by the purchaser shall be submitted by the supplier for distribution before commencement of supply. Adequate copies of acceptance & routine test certificate, duly approved by the purchaser shall accompany the dispatched consignment.

8.4.2 All records of routine test reports shall be maintained by the Supplier at his works for periodic inspection by the Purchaser.

8.4.3 All test reports of tests conducted during manufacture shall be maintained by the Supplier. These shall be produced for verification as and when requested for by the Purchaser.

9.1 PACKING & FORWARDING :

9.2 All insulator fittings shall be packed in double bags, one HDP bag (inner) and one gunny bag (outer) or in double gunny bag. The gross mass of the each packing shall not normally exceed 50 Kg.

9.3 The packing shall be of sufficient strength to withstand rough handling during transit, storage at site and subsequent handling in the field.

10.1 TEST CHECKING OF MATERIAL AT STORES

The material received in the stores of the NIGAM shall be subjected to the test

checking at stores before final acceptance of the material, the procedure for the same shall be as under :

10.2 SAMPLING


inspected lot received in stores shall be selected for test checking of material and shall be got tested. The sample selection shall be done in the presence of supplier or his authorised representative for which 7 days notice shall be given to the supplier.

10.3 TESTS

10.3.1 The following tests shall be carried out on the above items :

a) Visual Examination, Verification of Dimension, weight and marking. b) Mechanical Strength Test ( for LT Pins only). c) Galvanisation (Uniformity) Test.

67

Only those test shall be conducted at CTL for which facility with CTL is available. 10.3.2 Test of the material shall be got done at the test laboratory of the NIGAM or any other test laboratory designated by the Chief Engineer (MM). For witnessing of the testing, 7 days notice shall be given to the supplier stating date, time & place where the test is to be conducted. In case the supplier do not attend for witnessing the testing, the testing shall be proceeded and completed and action taken as per the contract.

10.3.3 The witnessing officers of the NIGAM or as designated by the purchaser shall send copies of test reports to the purchaser, consignees and the supplier.

11. CRITERIA FOR ACCEPTANCE

11.1 Visual Examination, Verification of Dimension, weight and marking .

As per specification/ ISS

11.2 Mechanical Strength Test (for LT Pins only)

In case of failure of sample in Mechanical Strength Test, the material contained in the lot / sub-lot to which the sample belongs, shall be rejected. The rejected material shall have to be replaced by the supplier free of cost.


11.3.1. The sample(s) shall be first tested for (n-2) number of dips where (n) is specified number of dips in the contract. If the sample(s) does not pass the uniformity of Galvanisation Test for (n-2) dips, the material shall be rejected and the material relating to relevant lot / sub-lot to which sample(s) pertains shall have to be replaced by the supplier free of cost.




12.0 TEST CHARGES :

All test charges incurred towards test checking of the material received in our stores

shall be borne by the NIGAM.

68

13.1 PAYMENT :

Payment shall be made only after receipt of successful test report from the CTL on the samples selected from the material received at the stores.

69


A Govt. of Rajasthan Undertaking



L.T.Pins & Hardware Fittings for L.T.Shackle Insulators

S.No. Technical specification Name of IS/other Other particulars

to which material/equipment/ standard specification if any. Machinery/T&P shall conform to which material should

conform

1. Specification for Insulator fittings IS:7935/1975 for overhead power lines with a nominal voltage upto and including 1000 V

2. Methods of testing weight, thickness IS:2633/1986

& Uniformity of coating on Hot Dip Galvanised articles.

3. Specification for electroplated coating IS:1573/1986

of zinc on iron and steel

4. Specification for Zinc IS:209/1992

5. Specification for porcelain insulators IS:1445/1977 for overhead power lines with a nominal voltage upto and including 1000 V.

6. Specification for carbon steel forgings IS:2004/1991

for general engineering purposes.

7. Technical supply conditions for threaded IS:1367 fasteners. Pt-I/1980

Pt-II/1979 Pt-III/1991

8. Specification for insulator fittings for IS:2486(Pt.I)/ 1993

overhead power lines with a nominal voltage greater than 1000 V - General requirements & tests.

70

9. Recommended practices for hot dip IS:2629/ 1985 galvanizing of iron & steel.

S.No. Technical specification Name of IS/other Other particulars

to which material/equipment/ standard specification if any. Machinery/T&P shall conform to which material should

conform

10. Fastners - single coil rectangular IS:3063/1994 section spring lock washers.

11. Specification for Hexagon Head Bolts, IS:1363/ 1992(Pt.I/II/III)

Screws & Nuts of product grade `C'.

12. ISO Screw Threads-Limit of size for IS:4218 (Pt.VII)/ 1978 commerceal bolts & nuts (diameter range 1 to 39 mm)


(Signature)

Name & Designation


71

Schedule- A

GUARANTEED TECHNICAL & OTHER PARTICULARS OF GALVANISED M.S.FORGED L.T.PINS

S. No.

Description Particulars

1. MANUFACTURER'S NAME & ADDRESS

i) OFFICE

ii) WORKS

2. STANDARD SPECIFICATION TOWHICH THE INSULATORS PINS SHAL CONFORM

IS:7935/1975 (Fig.2) Latest & other relevant ISS

3. DIMENSIONS OF PIN:

A) LENGTH OF PIN 260 MM i) SHANK LENGTH 125 MM ii) STALK LENGTH 135 MM B) THICKNESS OF STALK COLLER 5 MM C) DIAMETER OF STALK

i) AT TOP 16 MM ii) AT COLLAR 32 MM D) DIAMETER OF SHANK 16 MM E) LENGTH OF THREADS ON BOTH

SIDES

i) STALK 32 MM + 3 MM ii) SHANK 75 MM F) THICKNESS OF NUT (M16)

i) MAXIMUM 15.9 MM ii) MINIMUM 14.1 MM G) SPRING WASHER THICKNESS (M16

SIZE) 3.5 MM + 0.2 MM

4. TOLERANCE ON VARIOUS DIMENSIONS

± 5% on all dimensions but tolerance of collar thickness on plus side upto 2 mmand on minus side upto 0.5 mm.

5. MINIMUM FAILING LOAD 2.0 KN 6 WEIGHT OF PIN (approx) 0.425 Kg ± 2% Tolerence 7 TYPE OF GALVANISATION

i) L.T. PIN HOT DIP GALVANISED ii) NUTS & SPRING WASHERS HOT DIP/ELECTRO- GALVANISED.THE

MIN. LOCAL THICKNESS OF ELECTROPLATED ZINC COATING SHALL BE 25 MICRON AS PER SERVICE GRADE NO.4 OF IS:1573/1986.

8. MARKING 9. DETAILS OF PACKING double bags, one HDP bag (inner) and

one gunny bag (outer) or in double gunnybag

SIGNATURE OF BIDDER WITH SEAL

72

Schedule‐ B

GUARANTEED TECHNICAL & OTHER PARTICULARS OF L.T.SHACKLE HARDWARE FITTINGS

S. Description Particulars 1. MANUFACTURER'S NAME & ADDRESS :

i) OFFICE

ii) WORKS 2. STANDARD SPECIFICATION TO WHICH THE

H/W FITTINGS SHALL CONFORMIS:7935/1975 (FIG.3) LATEST & OTHER RELEVANT ISS

3. DIMESIONS OF H/W FOR L.T SHACKLE INSULATOR:

A) LENGTH OF STRAPS 185 MM B) WIDTH OF STRAPS 30 MM C) THICKNESS OF STRAPS 3 MM D) DIAMETER OF HOLES AT THE END OF

STRAPS. 14 MM

E) LENGTH OF BOLTS 115 MM F) DIAMETER OF BOLTS 12 MM G) DIAMETER OF BOLT HEAD 17 MM H) THICKNESS OF BOLT HEAD 8 MM I) THICKNESS OF NUTS

i) MAXIMUM 12.2 MM (M12) ii) MINIMUM 10.4 MM J) SHAPE OF BOLT HEAD & NUT HEXAGONAL K) LENGTH OF THREAD PORTION OF BOLT. 65 MM L) GALVANISED SPRING WASHER

THICKNESS.(M12 SIZE)2.5 MM + 0.15 MM

4. TOLERANCE ON VARIOUS DIMENSIONS ± 5% 5 WEIGHT OF COMPLETE H/W SET 0.475 KG (APPROX.) ± 2%

Tolerence 6 TYPE OF GALVANISATION

i) STRAPS HOT DIP GALVANISED ii) BOLTS HOT DIP GALVANISED iii) NUTS & SPRING WASHERS HOT DIP/ELECTRO-

GALVANISED.THE MIN. LOCALTHICKNESS OFELECTROPLATED ZINC COATING SHALL BE 25 MICRON AS PER SERVICE GRADE NO.4 OF IS:1573/1986.

7. MARKING

8. DETAILS OF PACKING double bags, one HDP bag (inner) and one gunny bag (outer) or in double gunny bag

9. ANY OTHER PARTICULARS WHICH THE TENDERER MAY LIKE TO GIVE.

SIGNATURE OF BIDDER WITH SEAL

73

TECHNICAL SPECIFICATION AND OTHER REQUIREMENT FOR 33 KV and 11 KV PIN INSULATORS

SCOPE :This specification covers the design, manufacture, testing, supply and delivery of 33 KV/11 KV /LPin Insulators for use of 11 KV over head power lines in Rajasthan.

1.0 The 33 KV/ 11 KV Pin Insulator shall be brown glazed porcelain and shall have

minimum failing load of 10 KN/5KN 2.0 The 33 KV/11 KV Pin insulator shall comply in all respects with the IS:731/1971

(With latest amendments). 3.0 The insulator marked with ISI certification mark will be given preference.

4.1 GENERAL REQUIREMENT :

a) The porcelain should be sound, free from defects thoroughly vitrified and

smoothly glazed.

b) The glaze of the insulators shall be brown in colour. The glaze shall cover all the porcelain parts of the insulators except those which serve as supports during fixing or are used for the purpose of assembly.

c) The design of the insulator shall be such that the stresses due to

expansion and contraction in any part of the insulator shall not lead to deterioration. The porcelain shall not engage directly with hard metal.

d) Cement used in the construction of the insulator shall not cause fracture by

expansion or loosening by contraction and proper care shall be taken to locate the individual parts correctly during cementing. The cement shall not give rise to chemical reaction with metal fitting and its thickness shall be uniform as possible.

4.2 THIMBLES :

The insulators shall suitably be provided with cemented in zinc or lead thimbles. 4.3 FAILING LOAD :

The 33 KV Pin Insulator shall have a minimum failing load of 10 KN . The 11 KV Pin Insulator shall have a minimum failing load of 5 KN .

4.4 THREADS :

The Pin Insulators with cemented in thimbles shall have the threads suitable for

use with large & small steel head galvanised M.S. Forged Pins covered under ISS:2486 (with its latest amendments if any).

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4.5 DRAWING :

The bidder shall submit detailed drawing along with bid showing design and dimensions in absence of which, the offer is likely to be ignored.

4.6 TESTS BEFORE DESPATCH :

The material shall be subjected at manufacturer's works before dispatch to the

routine & acceptance tests given here-under as per IS:731/1971 (latest amended). 4.7 ROUTINE TESTS :

These tests are to carried out to check various requirements of Pin insulators

which are likely to vary during production. The following tests shall be conducted / carried out on each insulator by the bidder at his works as per relevant IS:731/1971 (Latest amended) and he should furnish certificate / record thereof during pre-dispatch inspection:-

i) Visual Examination ( clause 10.13) ii) Electrical Routine Test (clause 10.15)

4.8 ACCEPTANCE TESTS :

These tests shall be carried out on the samples taken from the lot for the purpose of the acceptance of lot which are to be conducted as per relevant IS:731/1971 (latest amended) :

i) Verification of dimensions (Clause 10.5) ii) Temperature Cycle test (Clause 10.6) iii) Mechanical Failing Load test (Clause 10.8) iv) Puncture test (Clause 10.10) v) Porosity Test (Clause 10.11)

4.9 ADDITIONAL ACCEPTANCE TEST- INSULATION RESISTANCE TEST

In addition to acceptance test, insulation resistance test shall also be conducted on the samples. For carrying out test, the sampling procedure given in appendix C of IS:731/1971 (2nd revision) shall be followed.

The procedure for carrying out this test shall be as under:

a) Clean insulator and dry properly, then meggar the insulator with 2.5 KV/ 5 KV meggar.

b) IR value so measured should not be less than 1000 ( one thousand) mega ohms. The testing and criteria for conformity shall be as applicable to puncture test.

4.10 SAMPLING :

The sampling procedure as laid down in IS:731/1971 with latest amended shall be followed for carrying out specified acceptance tests.

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4.11 TOLERANCE ON DIMENSIONS / TEST RESULTS :

As per IS:731/1971 (latest amended).

4.12 TESTS AT SITE :

The purchaser reserves the right to conduct all tests on each type of insulator after arrival at site and bidder shall guarantee test certificates figures under actual service conditions.

4.13 PACKING :

All insulators shall be packed in suitable crates or boxes so as to withstand rough handling of packing.

4.14 GUARANTEED TECHNICAL AND OTHER PARTICULARS :

The full guaranteed technical and other particulars shall be given in the proforma

given in Schedule-V Any deviation from the specifications referred to above shall be supported by adequate justification.

4.14TEST CHECKING OF MATERIAL AT STORES

The material received in the stores of the NIGAM shall be subjected to the test checking at stores before final acceptance of the material, the procedure for the same shall be as under :

4.15 SAMPLING

One sample of 33 KV Pin insulator out of each sub-lot / lot of 1000 Nos. or part thereof, One sample of 11 KV Pin insulator out of each sub-lot / lot of 3000 Nos. or part thereof, from each inspected lot received in stores shall be selected from each store for test checking of material and shall be got tested. one extra sample of Pin insulator for conducting Puncture test.

The sample selection shall be done as soon as the material is received by the consignee, without calling the representative of supplier. However, testing at CTL or else where as arranged by NIGAM shall be done in the presence of representative of supplier after identification/ confirmation by the supplier’s representative that sample(s) so selected belong to them.

4.16TESTS


a) Visual examination, verification of dimensions, creepage distance etc, b) Mechanical failing Load Test c) Porosity test d) Puncture Test

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In case if the facility for conducting any of the above test(s) is not available at the

NIGAM’s CTL, the purchaser reserve the right to get such test (s) conducted at any independent NABL Test House.

i) For witnessing of the testing, clear 7 days notice shall be given to the supplier

stating date, time & place where the test is to be conducted. The testing shall be started after identification / confirmation of sample by the representative of the supplier that sample selected for testing pertain from the lot supplied by them. In case the supplier does not attend for witnessing the testing, the testing shall be proceeded and completed and action be taken as per the contract.

ii) The CTL shall send copies of test reports to the purchaser, consignees

and the supplier and Sr. Accounts Officer (CPC).

iii) Only those tests shall be conducted at CTL for which facility with CTL is available.


In case of failure of any of sample (s) in any of the above tests, the material contained in the lot / sub-lot received in store to which the samples belong, shall be rejected. The rejected material shall have to be replaced by the supplier free of cost.

4.18 TEST CHARGES : All test charges incurred towards test checking of the material received in our stores shall be borne by the NIGAM

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TECHNICAL SPECIFICATION AND OTHER REQUIREMENT FOR 33KV, 800 AMP. ISOLATORS WITH & WITHOUT EARTH SWITCH WITH 24 KV POST INSULATORS

AND 11KV , 400 AMP. ISOLATORS WITH 24 KV POST INSULATORS WITHOUT EARTH BLADE ASSEMBLED

1.0 SCOPE:

This specification covers design, manufacture, assembly testing at manufacturer's works, packing and & delivery with accessories and auxiliary equipments at site(s) of 33 KV,800 AMP. Isolators with & without Earth Switch with 24 KV Post Insulators and 11 KV,400 AMP. Isolators without Earth Switch with 24 KV Post Insulators required for installation at various 33/11KV Sub Stations in Jaipur Discom. The manufacturer shall also provide design, drawing and bill of material for supporting structures for installation of their Isolators with and without earth switch.

It is not the intent to specify completely herein all details of the design and

construction of equipments. However, the equipment shall conform in all respects to high standards of engineering, design and workmanship and shall be capable of performing in continuous operation up to the supplier's guarantee acceptable to the Purchaser, who will interpret in a manner the meaning of drawings and specifications and shall have the power to reject any work or material which in his judgment is not in accordance herewith. The equipment offered shall be complete with all components necessary for its effective and trouble free operation alongwith associated equipments, interlocks, protection schemes etc. Such components shall be deemed to be within the scope of supply, irrespective of whether those are specifically brought out in this specification and/or the commercial order or not. All similar parts particularly movable ones shall be interchangeable.

2.0 STANDARDS :

Unless otherwise specified elsewhere in this specification, the rating as well as

performance and testing of the isolators shall conform to the latest revisions and amendments of the following standards available at the time of placement of order.

Sl. No.

Standard No.

Title

1.

2.

IS:9921

IEC:60129

Alternating current isolators (disconnectors) and Earthing switches.

-do-3. IS:2544/1973 Insulators.4. IS:5350 Outdoor cylinderical post (Pt.III/1971) insulators. 5.

6.

IS:2629/1985

IS:4759/1996

Recommended practice for hot dip galvanising of iron and steel. Hot dip galvanisation coating on structural steel.

7.

8.

IS:2633/1986

IS:1573/1986

Method of testing uniformity of coating on Zinc coated articles. Electroplated coatings of zinc on iron and steel.

9. IS:6735/994 Spring washers.

78

10. IS:2016/1967 Plain washers. 11. IS:5561/1970 Electrical power connectors. (Terminal connectors) 12. Indian Electricity Rules.13. IS:9530/1980 Recommonded practice for silver plating.14. BS:2816/1964 Testing of silver plating thickness15. IS:5925/1970 Recommended practice for silver plating for general engineering purposes.


3.2 The equipment covered in this specification shall meet the technical requirements listed below :

S.NO. Particulars

33 KV Isolators

11KV Isolator

A) PARTICULARS OF SYSTEM:

i) Nominal system voltage :KV(rms) 33 11 ii) Highest system voltage :KV(rms) 36 12

iii) Rated Frequency. :Hz. 50 50 iv) Number of phases. 3 3 v) System Neutral Earthing Effectively earthedEffectively earthed B) Service conditions As per clause No.4.0 As per clause No.4.0 C) Characteristics of a disconnector

or earthing switch:

The values of the Parameters/Particulars mentioned below shall not be less than the specified against each.

S.NO. Particulars 33 KV Isolators 11KV Isolator

1. Number of poles.

3

3

2. Class - Indoor or Outdoor Out door Out door

3. Rated voltage :KV(rms) 33 11

4. Operating mechanism Manual Manual

5. Type of disconnector.(AB) Triple pole, gang operated double break, central post rotating.

6. Rated insulation level:

a) 1.2/50 Micro Sec. lightning impulse withstand voltage.

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i) To earth & between poles: 170 75

KV (Peak) ii) Across the isolating 195 95

distance.KV(Peak)

b) One minute P.F. withstand 70 28 voltage.

i) To earth & between poles: 70 28 KV (rms)

ii) Across the isolating 80 32 distance.KV(r.m.s.)

7. Rated normal current-A (rms) 800 400 8) i) Rated short time withstand current for 25 16

three second. KA (rms)

ii) Rated peak withstand current: 62.5 40 KA(Peak)

3.3 SPECIFIC TECHNICAL REQUIREMENTS :

1. Phase to Phase separation(min.) 1200mm 760mm

(Centre to Centre)

2. Minimum centre to centre 400mm 300mm distance between two poles of same phase.

3. Size of base channel on which 100x50mm 100x50mm

insulators are to be mounted.

4. Size of vertical operating pipe(Down pipe)

i) Length 4.6m 6m for equipment without earth blade

5.

ii) Nominal bore. Minimum length of operating

25 mm

500 mm

25mm

500mm handle.

6. Nominal bore of phase 20 mm 20mm coupling pipe.

7. Minimum cross-sectional 500sq. mm(Min.) 50X50X4.5mm area of terminal pad .

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8.(a)Minimum cross-sectional 380 sq.mm (Min.)220sq.mm(Min.) area of fixed contacts. (95 Sq.mm.x4 Nos.) ( 55sq.mmX4 Nos.)

(b)Minimum cross-sectional 95 sq.mm. 55 sq.mm area of one finger

9. Minimum nos. of fingers 2 pairs 2 pairs in a fixed contact. (4 fingers)(4 fingers)

10. Diameter of Arcing Horn (Rod). 10 mm 8 mm

11. Size of flexible earthing connnector :

i) Minimum cross-sectional ---------160 sq.mm -------------

area. ii) Length. ----------150 mm --------------- iii) For operating handle 50 Sq.mm.x 150 mm length

12. Name of conductor for DOG

which Electric power connector shall be suitable.

13. Min. size of stainless steel

spring to be provided with

fixed contact. i) Gauge

14SWG

16SWG

ii) Outer diameter iii) Minimum nos of turns per

22mm 6 nos.

15mm 6 nos.

coil. iv) Min. total length.

14. Minimum number of guides to be provided for down pipe.

28mm

2 nos.

28 mm

3/2 nos.

15. Minimum size of bimetallic 75X75X1 mm 50X50X1 mm strip to be provided between

Aluminium terminal connector

and copper terminal pad.

16. Top & bottom pitch circle 76 mm 76 mm diameter of post insulator

( to be procured separately) for which isolator hardware

shall be suitable.

17. Numbers of minimum size of 4x3/8"dia 4X1/4” diabolts to be provided for

fixing terminal connector with terminal pad.

18. Max. temperature rise allowed -------25 degree cen.-------- above ambient temperature of 50 degree centigrade

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4.0 GENERAL TECHNICAL REQUIREMENTS : 4.1 The Isolators shall be constructed out of best quality of material suitable for

whether conditions prevailing in Rajasthan. The workmanship shall be of the highest grade and the entire manufacture shall be in accordance with the modern Engineering practices. All ferrous parts shall be given an anticorrosive finish and shall be hot dip galvanised. The other parts shall be substantially non corrosive.The bearings in the current path shall be shunted by flexible copper connectors of adequate cross section and the bearing housings shall be completely weather proof with arrangement to facilitate the lubrication of the bearings.

4.2 The Isolators shall be of tripple pole, gang operated, double break, three

posts with central post rotating, banging type suitable for outdoor horizontal mounting with one veritcal break earthing blade per pole for fixing on either side of the poles or without any earthing blades. The switch Isolators shall be manually operated. The operating handle shall have arrangement for lockingIsolators/earth switch in ÒN'and ÒFF' positions.

4.3 For reasons of safety, the switch isolator should be so designed that no

dangerous leakage current can pass from the terminals of one side to any terminals of the other side of the switch Isolator.

4.4 The frame of each Isolator and earthing switch shall be provided with reliable

earthing terminal for each phase for connection to an earthing conductor having a clamping bolt/screw of not less than 12mm diameter. The terminal shall be marked with Èarth' symbol. The isolators with earthing switch shall be provided with flexible earthing connectors between the earthing blade and the frame of isolator. The requirement of flexible earthing connector shall not be insisted in case of isolators without earthing blade.

4.5 The isolators shall be provided with arcing horns of fixed type with make before

and break after actual making and breaking of isolator main contacts. The arcing horn shall be made of G.I. Rod and their position shall remain unchanged after mechanical endurance test (slight welding is permitted for this fabrication purpose).

4.6 All similar materials and removable parts of similar equipment shall be

interchangeable with each other.

4.7 The vertical operating pipe and phase coupling pipe shall be of galvanised mild steel tube(medium class) as per IS-1161.

4.8 Suitable arrangement shall be provided to padlock the operating handle of

isolating switches and earth switch in ÒN' & ÒFF' positions.

4.9 All ferrous parts shall be hot dip galvanised and uniformity of zinc coating shall satisfy requirement of IS-2633. The pipes /tubes shall be galvanised in accordance with IS-4736.

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4.10 All contact surfaces shall be silver /nickel plated as per IEC:60129 and their temperature rise shall be maximum 25 degree centigrade. The current density shall be less than 2.5 Amps.per Sq.mm. in copper, or minimum cross sectional area shall be as specified.

4.11 The height of 2 x 24 KV pedestal post type(E-32) insulator (conforming to IS:5350

Part.III & IS:2544) stack to be used with 33 KV isolator hardware shall be 508 mm. 4.12 BASE CHANNELS :

The channels shall be of sizes mentioned in clause No.3.0 "Principal parameters" of this specification and shall conform to IS- 808.

4.13 BEARINGS :

4.13.1 The bearing assembly for each rotating central post shall have one number

taper thrust roller bearing at top & one number ball bearing at the bottom/other end of bearing housing. The entire mechanical load shall be suspended on thrust bearings. Cross sectional drawings of the bearings shall be furnished with the tender.

4.13.2 The vertical operating shaft shall be supported with taper thrust roller

bearing on the top and atleast two guides in between at uniform interval alongwith its length in order to ensure smooth and easy operation.

4.13.3 A galvanised MS Angle/channel of suitable length shall be provided for fixing

of fourth bearing assembly. The holes provided shall be of movable type at equal distance to that of base channel holes.

4.14 OPERATING MECHANISM :

4.14.1 The operating mechanism shall be suitable for normal operations by one

man without undue efforts. The mechanism shall be so designed that all the three blades are in positive continuous control throughout the entire cycle of operation. It shall not be possible after final adjustment have been made for any part of the mechanism to be displaced at any point in the travel so as to allow improper functioning of switch, whether the switch is in opened or in closed condition.

4.14.2 ll G.I. Pipes used in operating mechanism of isolators and earth switches shall be of medium class as per IS-1161.

4.14.3 The Isolators with or without earthing switches complete with the operating mechanism should not come out of its own in open or closed position due to the effect of gravity, wind pressure, vibrations, reasonable shocks or accidental touching of operating rods. The arrangement made and stoppers provided to prevent over travel shall be clearly shown in the tender drawings.

4.14.4 The Isolators should also be capable of resisting in closed position, the

dynamic and thermic effects of the maximum possible short circuit current

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at the installation point.Their construction should be such that it should not open under the influence of short circuit current.

4.14.5 The earthing of operating handle shall be made through flexible copper strip

of size as per IS:9921(Pt.III)-1982, connected to the supporting metallic structure.

4.15 CONTACTS :

4.15.1 The fixed contacts shall be of spring loaded reverse loop type as detailed in Clause No.4.2 (8&9) . The minimum length of each finger should be 105 mm or equal to type tested isolator whichever is higher for 33KV 800 Amp. isolator. The moving contacts shall be of solid hard drawn electrolytic copper of tubular sections.

4.15.2 The contacts and switches blades shall be of liberal cross section to withstand the rated continuous current. The copper contacts shall be silver/ nickel plated as per IEC:60129 and female contacts fingers shall be provided with spring of Phospher Bronze or stainless steel. The spring shall be fixed in the finger contacts through taflon/nylon insert at both ends so that no transfer of current is possible through spring and direct electric heating of springs is avoided.

4.15.3 The contacts must be made of liberally rated electrolytic hard drawn copper suitably plated to withstand damage on account of weather conditions prevailing at site and accidental arcing. High pressure contact switch shall be designed with a contact pressure 1/2 (Half)Lb per Amp. of capacity. The tenderer shall specifically confirm that the material components and cross sectional areas of all current carrying parts shall be either exactly same or superior to that of isolator got type tested for short circuit test,temperature rise test and Mili volt drop test as per relevant standards.

4.15.4 Full details of the contacts and switch blades shall be given with cross sectional drawings to dimension. The temperature rise of the contacts shall not exceed 25 degree centigrade at an ambient temperature 50 Degree C.

4.15.5 The current density in current carrying parts shall not exceed 2.5A per sq.mm for copper and 1.0A per sq.mm for Aluminium considering with & without holes for overlapping for which supporting calculations must be submitted with offer.

4.16 TERMINAL PAD :

The terminal pad shall be made of electrolytic copper flat and should be liberally sized, so as to receive terminal connectors through minimum 4 Nos. of nuts and bolts of suitable size.

4.17 ELECTRIC POWER CONNECTORS (TERMINAL CONNECTORS) : 4.17.1 The isolators shall be provided with 6 Nos of bimetallic rigid type universal

terminal connectors of aluminium alloy suitable for conductors as per clause No.5.0. The size of terminal connector should match with terminal pad size. The

84

terminal connector shall also be suitable for horizontal and vertical take off arrangement.

4.17.2 Thickness of bimetallic strip between terminal pad and aluminium terminal connector shall be atleast 1 mm. The current density in terminal connectors shall be less than 1.0 Amps. per Sq.mm. The connectors shall conform to all the test requirement of IS-5561 with latest amendments.

4.18 EARTHING BLADES :

4.18.1 The earthing blades wherever required shall be manually operated in the

manner similar to the main blades. The earth switch shall match the main isolators in quality and shall be capable of withstanding all electrical and mechanical stresses. The earthing blades shall be counter balanced to ensure smooth and easy operation. All ferrous parts used in the operating mechanism shall be galvanised. The design of earth switch shall match with main switch isolator in all respects.

4.18.2 The earth switch moving blades and contacts shall be of copper, the cross

sections of which shall be either exactly same or superior to that of main switch or earth switch got type tested for short circuit test. This shall be specifically confirmed by the tenderer.

4.18.3 The earth switch shall be mechanical interlocked with associated isolator to

prevent the earthing blades from closing when the main blades are closed and vice versa,. The tenderer are advised to enclose tender drawing to show salient feature incorporated in the switches to ensure satisfactory performance of this duty.

4.19 BOLTS, NUTS & WASHERS :

4.19.1 All bolts, nuts & washers required for assembling the equipment and for

fixing them on to the structure shall be galvanised and shall be supplied with the equipment at no extra cost.

4.19.2 Bolts & nuts shall also be provided with lock washers and lock nuts required

for fixing post insulators/post insulator stacks on base plate/base channel.

4.20 ACCESSORIES AND FITTINGS :

The following accessories and fittings shall be provided with the isolators.

i) Handle suitable for pad locking in ÒN' & ÒFF' position.

ii) Three earthing terminals having clamping bolts of atleast 12mm diameter.

iii) Name Plate shall be provided on the equipment as per IS/9921.

iv) Galvanised arcing horns of liberally rated renewable rod type with make before

85

and break after arrangement. v) Mechanical interlock for earthing swithes.

vi) Base Channels.

vii) Electric power connectors (Terminal connectors)

4.21 CLEARANCES : The isolators shall have clearances conforming to relevant IS and should meet the requirements of the impulse voltage tests as specified therein.

4.22 The equipment covered by this specification shall be used outdoor and

maximum temperature attained by any part of the equipment in service at site conditions and full load current shall not exceed the permissible limits mentioned in IS:9921 at an ambient temperature of 50 Degree C. Tenderers are required to mention specific degree of maximum temp. rise in GTPs.

4.23 The temperature rise test after fitting terminal connectors shall also be carried

out as routine test on one switch isolator out of each lot offered for inspection. The limit shall not exceed those specified under this specification.

4.24 Where Porcelain Insulators are offered they shall be made of homogeneous and

vitreous porcelain of high mechanical and die-electric strength. It shall have sufficient mechanical strength to sustain electrical and mechanical loading on account of wind load, short circuit forces etc., Glazing of the porcelain shall be of uniform brown or dark brown colour with a smooth surface arranged to shed away rain water. The porcelain shall be free from laminations and other flaws or imperfections that might affect the mechanical or dielectric quality. It shall be thoroughly vitrified, tough and impervious to moisture. The porcelain and metal parts shall be assembled in such a manner and with such material that any thermal differential expansion between the metal and porcelain parts throughout the range of temperature specified in this specification shall not loose the parts or create undue internal stresses which may affect the mechanical or electrical strength or rigidity of the unit as a whole or stack of two units. The assembly shall not have excessive concentration of electrical stresses in any section or across leakage surfaces. Cement used in the construction of post insulators shall not cause fracture by expansion or loosening by construction and proper care shall be taken to locate correctly the individual parts during cementing. The cement used shall not give rise to chemical reaction with metal fittings and its thickness shall be uniform. The insulator shall be suitable for water washing by rain or artificial means in service condition. Profile of the insulator shall also conform to the relevant IS.

4.25 Cap to be provided on top of the insulator shall be of high grade cast iron or

malleable steel casting. It shall be machine faced and hot dip galvanised. The cap of 24KV Post Insulators shall have four numbers of tapped holes spaced on a pitch circle diameter of 76mm . The threads of the tapped holes in the post insulator metal fittings shall be cut after giving anti corrosion protection and

86

shall be protected against rust by greasing or other similar means, all other threads shall be cut before giving anticorrosion protection and shall conform to IS: 4218 with latest version thereof The tapped holes shall be suitable for bolts with threads having anticorrosive protection.

The effective depth of threads shall not be less than the nominal diameter of the

bolt. The cap shall be so designed that it shall be free from visible corona. 4.26 The casting shall be free from blow holes, cracks and such other defects.

4.27 All the ferrous metal parts shall be given an anticorrossive finish and shall

be hot dip galvanised smoothly as per IS:3638 (as amended upto date), IS:2633 or any other equivalent authoritative standard. The other parts shall be substantially non corrosive. The material shall be galvanised only after shop operations upon it have been completed.The metal parts before galvanising should be thoroughly cleaned of any paint, grease, rust, scales or alkali or any foreign deposit which are likely to come in the way of galvanising process. The coating on the metal parts shall withstand minimum four one minute dips in copper sulphate solution as per the relevant IS.

4.28 The insulator unit shall be assembled in a suitable jig to ensure correct

positioning of the top and bottom metal fittings relative to one another. The faces of the metal fittings shall be parallel and at right angles to the axis of the insulator and the corresponding holes in the top and the bottom metal fittings shall be in a vertical plane containing the axis of the insulator.

4.29 It shall be the sole responsibility of the Supplier to carry out thorough inspection

and quality checks on the insulators at the insulator supplier's works, before offering the isolators for Purchaser's inspection.

4.30 The porcelain and hardware surface coming in contact with cement shall be

coated with bituminous paint for cushioning to relieve mechanical stress caused by temperature variation and cement expansion.

4.31 The post insulators shall conform to IS:5350. The total creepage distance of 24KV

post insulator as individual unit shall be minimum 430mm .

4.32 Following makes of the Post Insulators shall be acceptable for the supply of 33 KV & 11 KV Isolator

i) M/s.Jaipur Glass & Potteries, Jaipur. ii) M/s.India Potteries, Kolkata. iii) M/s.Bikaner Ceramices, Bikaner. iv) M/s.CJI Porcelain, Khurja. v) M/s.Vishal Melleable, Ankeleshwar. vi) M/s.Allied Ceramices Pvt. Ltd., Kolkata. vii) M/s.WSI, Chennai. viii) M/s.IEC, Bhopal. ix) M/s.MIL, Allahabad. x) M/s.Jay Shree Insulators, Vadodara.

87

xi) M/s.Birla NGK Insulators Pvt. Ltd., Halol. xii) M/s.MIL, Abu Road. xiii) M/s.Sarvana Insulators Ltd., Kurinji Padi, Dist Cuddalore,

(Tamilnadu). xiv) M/s BHEL

4.33 Besides above, the Post Insulators manufactured by the vendors approved by the

Power Grid Corporation of India Ltd (PGCIL) and National Thermal Power Corporation (NTPC) shall also be acceptable.

5. TEST

The manufacturer is required to conduct following routine tests as per relevant IS on the Isolators complete with required Post Insulators at manufacturer's works .

5.1ROUTINE TEST :

1. Routine mechanical test on post insulators. 2. Routine electrical tests on post insulators. 3. Tests as per IS:2633.


The following tests shall be got conducted in presence of purchaser's representative as per relevant standards at the place of manufacturer before dispatch without any extra charges. The tests at Sr. No.1 to 6 are to be carried out on completely assembled isolator as per IS:9921(Pt.IV). The sampling for the inspection of completely assembled isolators, offered for final inspection shall be on 10% of offered quantity(unless otherwise specified). The tests at Sr. No.7 to 12 are to be carried out on Post insulators as per IS:2544 and sampling will also be as per same IS, at original manufacturer’s works.

1. Measurement of resistance of main circuit of Isolator as per IS:9921 (Part.IV). 2. Mechanical operating test on atleast one sample selected at random from each

type & rating. 3. Mechanical endurance test shall be done as acceptance test on one Isolator

of each type & rating from every lot. Mechanical endurance test shall be conducted on the main switch as well as earth switch of one disconnector of each type & rating. Bare contacts shall not be acceptable in any case.

4. Verifications of dimensions as per approved drawing on one Isolator set of each type & rating.

5. Temperature rise test on one set of Isolator of each rating from the offered lot. 6. Preece Test on one Isolator of each type and voltage rating as per relevant IS. 7 Verification of dimensions of post insulators. 8. Temperature Cycle Test on post insulators. 9. Mechanical strength Test on post insulators. 10. Puncture Test on post insulators. 11. Porosity Test on post insulators. 12. Galvanizing Test on post insulators.

88

5.3 TEST ON BOUGHT OUT ITEMS

Tests are not required to be performed on boughtout equipments like terminal connectors etc. at the works of manufacturer except operational tests. Furnishing Test Certificate of Isolators and Post Insulators from the original equipment manufacturers shall be deemed to be satisfactory evidence. Inspection of the tests at Sub-contractors works will be arranged by the supplier whenever required.

At the option of the purchaser, the material received in the stores may be utilized in the field after receipt of successful test reports from CTL, Jaipur

6.0 TOLERANCE :

Tolerance shall be allowed as per respective /relevant Indian Standards unless otherwise specified.

However, no negative tolerance shall be allowed on current carrying parts.

7.0 INSPECTION

All the tests and Inspection shall be made at the place of manufacturer unless otherwise

especially agreed upon by the tenderer and purchaser at the time of purchase. The tenderer shall offer required numbers of post insulators for Purchaser’s inspection and after clearance of insulator, he will offer assembled Isolators for purchaser’s inspection. The tenderer shall afford the inspection officer(s) representing the purchaser all reasonable facilities without charges, to satisfy him that the material is being furnished in accordance with this specification. The purchaser has the right to have the tests carried out at his own cost by an independent agency whenever there is a dispute regarding the quality of supply.

The Inspection may be carried out by the purchaser at any stage of manufacture/

before dispatch as per relevant standard.

Inspection and acceptance of any material under the specification by the

purchaser, shall not relieve the tenderer of his obligation of furnishing material in accordance with the specification and shall not prevent subsequent rejection if the material is found to be sub-standard.

The purchaser reserves the right to insist for witnessing the acceptance/ routine testings of the bought out items.


The material received in the stores shall be subjected to the test checking at stores before final acceptance of the material, the procedure for the same shall be as under.

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8.2 SAMPLING

One sample out of each sub-lot / lot consisting of following quantities or part thereof from each inspected lot received in stores shall be selected for test checking of material and shall be got tested. The selection of sample from the material received at stores shall be done as soon as material is received in stores without the presence of the representative of the supplier. However, testing of sample(s) at CTL shall be carried out in the presence of representative of the supplier after identification / confirmation by him that sample so selected belongs to them.

33 KV 800 Amp. Isolator with & without E.B. with Post Insulator– 50sets

11 KV 400 Amp. Isolator without E.B. with Post Insulator – 100 sets

8.1(a) one extra sample of 24 KV post insulator for conducting Puncture test.

8.3 TESTS


a) Visual examination , verification of dimensions, weight and marking as per PO/ GTP/ Approved drawing.

b) Checking of current carrying parts as per approved drawings.

c) Post Insulators : - i) Mechanical strength test.

ii) Porosity test iii) Puncture Test

d) All galvanized parts. - Uniformity of galvanization test.

In case if the facility for conducting any of the above test(s) is not available at the

NIGAM’s CTL, the purchaser reserve the right to get such test (s) conducted at any independent NABL Test House.

For witnessing of the testing, clear 7 (seven) days notice shall be given to the

supplier by fax/ speed post stating date, time & place where the test is to be conducted. In case the supplier do not attend for witnessing the testing, the testing shall be proceeded and completed and action be taken as per the contract.

The Officer Incharge of Central Testing Lab (CTL) Jaipur shall send copies of test reports to the purchaser, consignees and the supplier.


a) Visual examination , verification of dimensions, weight and marking.

As per Specification/GTP/Approved drawing.

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b) Checking of current carrying parts as per approved drawings.

If the dimensions of the current carrying metal part are in conformity with approved

drawings, the material shall be accepted. When the dimensions of above parts are less then those minimum specified in the approved drawings but upto a limit of 5%, the material contained in the Lot ./ Sub-lot to which the sample belong shall be accepted subject to the conditions that the current density in above part is inconformity with contract and deductions at the rate of 2% cost of above parts for every 1% or part thereof reduction in weight due to less dimensions. The deduction shall be made for weight of above parts calculated on the basis of dimensions observed and found less. The weight shall be compared with one calculated on the basis of the minimum dimensions for the parts approved in the drawings. When the dimensions are less than more than 5% as compared to the dimensions as per approved drawings, the material contain in the lot/ sub-lot to which the sample belongs shall be rejected and shall have to be replaced by the supplier.

c) Post Insulators : i) Mechanical strength test. ii) Porosity test iii)

Puncture test.

In case of failure of any of samples in any of the above test , the material contained in the lot / sub lot received in the stores to which the sample(s) belong shall be rejected. The rejected material shall have to be replaced by the supplier free of cost.

d) All galvanized parts. - Uniformity of galvanization test. i) The sample(s) shall be first tested for (n-2) number of dips where n is specified

No. of dips in the contract. If the sample does not pass the uniformity of galvanization test for (n-2) dips, the material shall be rejected and the material relating to relevant sub-lot/ lot to which the sample(s) pertains shall have to be replaced by the supplier free of cost.

ii) If the sample has passed the uniformity of galvanization test for (n-2) dips, then it shall be tested for (n-1) dips. If the sample has not passed the uniformity of galvanization test with (n-1) dips, the material pertaining to relevant lot/sub- lot shall be accepted with a deduction @ 4% of cost of galvanized material parts.

iii) If the sample passed the uniformity of galvanization test with (n-1) dips, then sample shall be tested for last one dip of one minute to complete the test for `n' dips. If the sample does not pass the uniformity of galvanization test with `n' dips, then the material pertaining to relevant lot/sub-lot shall be accepted with a deduction @ 2% of cost of galvanized material parts.

iv) If the sample(s) have passed the test with number of dips as specified in the

contract (n), then material pertaining to relevant lot/sub-lot shall be accepted.

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8.5 TEST CHARGES :

All test charges incurred towards test checking of the material received in our stores shall be borne by the NIGAM except that of personal expenses of the representative of the supplier for witnessing the tests.

9.0 OPERATIONS AND MAINTENANCE INSTRUCTION MANUALS:

The successful tenderers shall have to supply three sets of operations and maintenance instruction manuals per set of isolator alongwith the erection manual and requisite detailed drawings of the equipments covered by this specification.

10.0 NAME AND RATING PLATE :

All items of the equipments included in this specifications shall be provided with a

weather and corrosion proof plate of name/trade mark of manufacturer, rating and TN in according with the provision of the IS:9921. The name & rating plate should be riveted on base channel. Further there should be proper marking on the base channel for identifying RYB phase.

11.0 GUARANTEED TECHNICAL PARTICULARS:

The tenderer shall furnish the guaranteed technical particulars as per relevant IS

12.0 COMPLETENESS OF EQUIPMENT:

All fittings, accessories or material which may have not been specifically mentioned in this specification, but which are usual or necessary for the equipment shall be deemed to have been included in this specification. All equipments shall be complete in all respect.

13.0 LATENT DEFECTS, ERRORS & OMMISSIONS:

Any material/ equipments or part thereof that develops defects, errors or ommissions in the apparatus, not disclosed prior to the final acceptance by the purchaser, but occur or are disclosed during the guarantee period, shall be corrected promptly. The equipment or part thereof shall be replaced by the supplier free of charges and all expenses for the transportation, handling, installation of such replacement or any other incidental charges shall be born by the supplier.

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TECHNICAL SPECIFICATION FOR PURCHASE OF VARIOUS STEEL SECTIONS

1. SCOPE:- 1.1 This specification covers for design, manufacture, stage testing, inspection & testing

before dispatch, packing supply and delivery of steel plates, strips, section, flats, bars etc. for use in structural work.

1.2 These sections shall be suitable for welded, bolted and riveted structures and for general engineering purposes.

1.3 Where welding is employed for fabrication and guaranteed weld-ability is required, welding procedure should be as specified in IS:9595:1980.

1.4 All steel items shall be supplied galvanized as per ISS 2.0 Standards:

Except as modified in this specification, the material, and purpose of material covered under “SCOPE” clause 1.1 to 1.3 shall confirm to the latest revision with amendments thereof the following bureau of Indian Standard & where the relevant ISS is not available, the material/equipment should comply the latest B.S.S.

S.No. Bureau of Indian Standards. ISNo.

Title

1 2062 Steel for General structural purpose (Fifth revision)

2 228 Method of chemical analysis of steel (secondrevision)

3 1608/1995 Mechanical testing of metals- Tensile testing(Second Revision)

4 1757/1988 Method for charpy impact test (V notch) for metallic material (second revision)

5 3803 Part.I/ 1989 Steel-conversion of elongation values Part.I Carbon & alloy Steels (Second revision)

6 8910/1978 Ground technical delivery requirements for steel & steel products.

7 10842/1984 Testing & evaluation procedure for Y groove crackability test.

8 1786/1985 High Strength Deformed Steel Bars and wires for concrete reinforcement.

9 1599/1985 Method for bend test(second revision)

10 1052/1985 Rolling and cutting tolerances for hot rolled steel products (Third Revision).

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3.1 GENERAL TECHNICAL REQUIREMENT

The technical, parameters to which the steel sections shall confirm are as under:- 3.2 MECHANICAL PROPERTIES:

a Grade A b. Designation Fe 410 W A c. Tensile strength min., mpa 410 d. Yield strength min., mpa <20, 20-40 >40

mm mm mm 250 240 230

e. Elongation percent, min.(at gauge length 5.65xSQRT (So)

23

f. Internal Diameter of Bend min. 3t g. Charpy V Notch Impact energy J, min.

3.3 CHEMICAL COMPOSITION a Grade A b. Designation Fe 410 W A c. Ladle Analysis, percent, Max. C- 0.23

Mn- 1.50 S - 0.050 P - 0.050 Si - 0.40

d. Supply condition. As rolled e. Carbon equivalent (CE) Max. 0.42 f. De-oxidation mode

3.4 MASS & STANDARD LENGTH

S.No

Name of the Steel Sections

Size in mm Mass in Kg. Per Metre

Required length in metre (Standard length)

1 MS Channel 100x50x6 As per ISS 8-11

2 MS Angle 65x65x6 As per ISS 8-11

3 MS Angle 50x50x6 As per ISS 8-11

4 M.S. Flat 50x6 As per ISS 8-11

3.5 TOLERANCE IN STANDARD LENGTH:- ±5% for all sections 3.6 TOLERANCE IN DIMENSIONS:- As per relevant IS 3.7 PACKING AND MARKING:-

a) Packing As per ISS b) Marking The steel sections shall be marked with colour

code as per IS and each product shall carry a tag or be marked with the manufacturer name or trade mark.

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3.7 WORKMANSHIP i) All finished steel shall be well and clearly rolled to dimensions, sections and masses

specified. The finished material, shall be reasonably free from surface flows, laminations, rough/jagged and imperfect edges and other harmful defects.

ii) Minor surface defects may be removed by the manufacturer. 4.0 IDENTIFICATION MARKING:

Each individual structure / section shall carry a code number conforming to component number given to it in the drawing / Bill of material. The code number of approved size shall be stamped with a metal dye of 16 mm size on the member and shall be legible. The name of manufacturers in suitable code and the word “IPDS”& “TN No” shall also be stamped / punched on each individual section with metal dye of not less than 16 mm size.

If the above marking is not found on the material received in the stores, the receipted challan shall not be given by the concerned stores. The challan shall only be issued after verification of material by the Store officer.

5.1 QUALITY ASSURANCE PLAN:

The bidder shall invariably furnish the following information alongwith his offer, failing which the offer shall be liable for rejection. Information shall be separately given for individual type of steel section.

i) Statement giving list of important raw materials, names of sub-supplier for the raw material, list of standards according to which the raw material are tested, list of tests normally carried out on raw material in presence of bidders representatives, copies of tests certificates.

ii) Information and copies of test certificates as in (i) above in respect of bought out items.

iii) List of manufacturing facilities available iv) Level of automation achieved and list of areas where manual processing exists. v) List of areas in manufacturing process, where stage inspections are normally

carried out for quality control and details of such tests and inspections.

The supplier shall submit the routine test certificates of bought out items and raw material at the time of routine testing.

6.0 PACKING & FORWARDING

The various sections of steel shall be packed in such a manner so that same should be able to resist hazard involved in transportation, unloading, stacking etc.

7.1 TESTS Tests before dispatch:- The various steel sections before dispatch shall be subject to following tests as per IS:2062 at the maker’s works.

ROUTINE TEST/ACCEPTANCE TEST: (i) Dimensional checking & visual inspection. (ii) Weight checking

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(iii) Chemical composition test (iv) Mechanical properties tests

8.1 INSPECTION The inspection shall be carried out on each lot separately. The following number of pieces selected at random shall be subjected to inspection/ testing and checking.

a) Workmanship and dimension checking : 1 samples from each 50 MT or

part thereof. b) Chemical test : One sample of each

section from the entire lot of material offered for inspection.

c) Tensile test : One sample from every 50 MT or part thereof of each section.

d) Bend test : One sample from every 50 MT or part thereof of each section.

All the tests and inspection shall be carried out at the place of manufacturer unless otherwise especially agreed upon by the bidder and purchaser at the time of purchase. The bidder shall afford all reasonable facilities without charges for the inspecting officer(s), to satisfy him that the material is being furnished in accordance with this specification. The purchaser has the right to have the tests carried out at his own cost by an independent agency whenever there is a dispute regarding the quality of supply.

The inspection may be carried out by the purchaser at any stage of manufacture/ before dispatch as per relevant standard.

Inspection and acceptance of any material under the specification by the purchaser, shall not relieve the bidder of his obligation of furnishing material in accordance with the specification and shall not prevent subsequent rejection if the material is found to be defective. The bidder shall keep the purchaser informed in advance, about manufacturing programme so that arrangements can be made for inspection.

The test for chemical and mechanical properties shall have to be arranged in presence of Inspecting officer at recognized Lab.

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Schedule-A GUARANTEED & OTHER TECHNICAL PARTICULARS FOR VARIOUS STEEL SECTIONS

A. GENERAL 1 Maker's Name 2 Address for correspondence 3 Address of Works B. STANDARDS & SPECIFICATION 1 Dimension As specified 2 Testing As per IS:2062 (Latest

amended). If not supported by test certificate of steel from main producers.

C. TOLERANCE As per IS:1852-1985 (Latest amended)

Mechanical properties: a Grade A b. Designation Fe 410 W A c. Tensile strength min., mpa 410 d. Yield strength min., mpa <20, 20-40 >40

mm mm mm 250 240 230

e. Elongation percent, min.(at gauge length 5.65xSQRT (So)

23

f. Internal Diameter of Bend min.

3t

g. Charpy V Notch Impact energy J, min.

-

Chemical composition a Grade A b. Designation Fe 410 W A c. Ladle Analysis, percent,

Max. C- 0.23 Mn- 1.50 S - 0.050 P - 0.050 Si - 0.40

d. Supply condition. As rolled e. Carbon equivalent (CE) Max. 0.42 f. De-oxidation mode

Mass & standard length : As specified. Tolerance in Dimension : As per relevant ISS: Marking :The steel sections shall be marked with colour

code as per ISS and each product shall carry a tag or be marked with the manufacturer name or trade mark.

Signature of Bidder Name

Designation_ Common authorized seal of bidder

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TECHNICAL SPECIFIICATION FOR SUPPLY OF SUB-STATION STRUCTURE FOR MOUNTING OF 11/0.4 KV TRANSFORMERS ON DOUBLE POLE / 33 KV LINE DP STRUCTURE/ 33 KV SUB-STATION STRUCTURE AND SUB-STATION STRUCTURE FOR SINGLE PHASE 16 KVA DT

1. SCOPE

This specification covers fabrication, testing & delivery of fabricated steel items as a complete package, complete in all respect as per GTP/Drawings (to be provided by the purchaser to the successful bidder). The steel sections generally used, tentative unit weight of fabricated item is as per GTP. The final bill of material for the purpose of payment shall be prepared and submitted by the supplier after approval of model assembly by the purchaser.

2. STANDARDS :

All materials and equipments shall comply in all respect with the requirements of the latest edition of the relevant Indian Standard Specification(s) except as modified in this specification. Where the relevant ISS is not available, the material / equipment should comply the latest BSS. All the items should be made / fabricated/tested from steel sections conforming to IS:2062 (latest amended).

3. DRAWING & MODEL ASSEMBLY :

3 sets of drawing shall be furnished by the successful bidder based on JVVNL drawing for according approval of the purchaser before commencement

4. MARKING




The finished product before acceptance shall be subject to inspection in respect of workmanship, checking of dimension/weight & testing as per requirement of relevant IS:2062 (latest amended), approved drawings and bill of material, at the suppliers works if not supported by test certificates of main producers viz. SAIL/TISCO/RINL. The certificate for type test (chemical composition & mechanical properties test) issued by prime producer(s) shall be furnished along with the inspection call to the SE(TW), otherwise testing shall be arranged at independent Lab on the cost of supplier. The certificate and relevant invoices shall be in the

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name of the firm on whom the order is placed by the Nigam. In case bidder use the steel sections manufactured by prime producers then the inspecting officer shall verify and record in the inspection report regarding stamping and mark of prime producers. The certificate(s) in the name of other parties/ sources shall not be accepted and in such cases the tests for chemical and mechanical properties shall have to be arranged in the presence of inspecting officer(s) at recognized lab.

The supplier shall present the latest Calibration Certificate(s) of testing instruments/ equipments to be used for the testing of the material covered in the purchase order to the authorized inspecting officer/inspecting agency of the purchaser. The testing instruments/ meters/ apparatus etc. should be got calibrated by the supplier from time to time from independent test laboratory/ house having valid accreditation from National/ Accreditation Board for testing and calibrating laboratories for testing equipments/ original manufacturer having trace ability to NABL/NPL or equivalent.

The calibration certificate(s) should not in any case be older than one year at the time of presenting the same to the inspecting officer/inspecting agency of the purchaser. The testing instruments/equipments should be duly sealed by the Calibrating agency and be indicated in the calibration certificate(s).


(d) Suitable accommodation. (e) Local conveyance between arrival point, place of stay, works and departure

point. (f) The supplier shall assist in arranging return ticket and reservation on the request


6. TESTS

Test before dispatch:- The various steel section/structure before dispatch shall be subject to following test as per IS:2062( latest amendment) at the manufacturer’s works Routine test/acceptance test

(i) Dimensional checking and visual inspection (ii) Weight checking (iii) Chemical composition test (iv) Mechanical property test

7. SAMPLING:

The inspection shall be carried out on each lot separately. The following number of pieces selected at random shall be subject to inspection/ testing and checking.

a) Workmanship and dimension checking : 3 % samples from finished item. b) Chemical test : One sample of each steel section

from the entire lot of material

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offered for inspection. c) Tensile test : One sample of each steel section

from every 50 MT or Part thereof. d) Bend test : One sample of each steel section

from every 50 MT or Part thereof.

8. TOLERANCE IN DIMENSIONS :

The tolerance(s) shall be permissible as per IS: 1852: (latest amended). Further the following tolerance(s) on fabricated items will also be allowed.

i) Tolerance in over all length ± 3mm ii) Tolerance in edge dimensions (centre of hole to end) ±2mm iii) Tolerance in hole centre ±2mm iv) Circular holes No tolerance v) Weight Tolerance +2% to (-) 4%


The bidder shall furnish the guaranteed technical particulars of the material as required in the schedule-A by mentioning specific figures therein. Any item of the GTP left unfilled or simply written as per ISS etc. shall be considered as incomplete GTP and such tender is liable to be rejected.

10. PACKING AND FORWARDING

The finished items complete in all respect dully inspected and cleared for dispatch, shall have to be delivered in Nigam's stores located anywhere in Jaipur Discom by Road. Unloading of material at store(s) is Suppliers responsibility.


The inspected material should be strictly in accordance to the GTP of the specification otherwise the material shall be treated as rejected and shall not be accepted.

12. WEIGHT

The weight of structure shall mean the weight of structures calculated byusing standard sectional weights of all steel structural members of the sizes indicated in the fabrication drawings and/or subsequently revised drawings and bill of material without taking into consideration the reduction in weight due to drilling of bolt-holes, skew cuts, chamfering etc. or the increase in weight due to galvanization.

The material shall be acceptable if found within permissible tolerance limit i.e. +2% and (-)4%.

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DETAILS OF APPLICABLE STANDARDS / SPECIFICATION/ MANUALS :

The material shall comply with the relevant provisions made in the following Indian Standards Specification (now BIS) with latest amendments.

1 IS:2062: (Latest amended) Raw material and Method of testing 2 IS:1852: (Latest amended) Rolling & cutting Tolerance

All materials and sections shall comply in all respect with the requirement of latest addition of relevant Indian Standard Specification except as modified in this Specification . Where the relevant ISS is not available, the material / sections should comply with the latest BSS. All the item should be made/ fabricated from steel sections conforming to IS:2062: (latest amended). Rolling and cutting tolerances for hot rolled steel products shall be governed as per IS:1852:(latest amended).

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SCHEDULE-A

GUARANTEED & OTHER TECHNICAL PARTICULARS FOR SUB-STATION STRUCTURE FOR MOUNTING OF 11/0.4 KV TRANSFORMERS ON DOUBLE POLE UNDER

A. GENERAL :

1. Name of firm : 2. Address for correspondence : 3. Address of Works :

B. STANDARDS & SPECIFICATION : 1. Dimension : As per approved drawing. 2. Testing a) Steel : As per IS:2062: (Latest amended). If not supported

by test certificate of prime producers. C. TOLERANCE :

a) Steel : As per IS:1852:(Latest amended) b) Length : +/- 3 mm c) Edge dimensions : +/- 2 mm d) Hole centre : +/- 2 mm e) Weight tolerance : +2% to (-) 4%

D) GUARANTEED WEIGHT OF STRUCTURE : As per BOM E) Properties of steel (for class À')

(a) Chemical composition. (i) Carbon % (Max.) 0.23 (ii) Manganese % (Max.) 1.50 (iii) Sulpher % (Max.) 0.05 (iv) Phosphorus % (Max.) 0.05 (v) Silicon % (Max.) 0.40 (vi) C.E. % (Max.) 0.42 (b) Mechanical Properties : UTS(Mpa) Min. 410 Y.S.(Mpa) Min. 240 El (%) Min. 23

Signature of Bidder Name Designation_ Common authorized seal of Bidder

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TECHNICAL SPECIFICATION FORHEAT SHRINKABLE TYPE CABLE JOINTING AND TERMINATION KITS FOR 33 KV AND 11 KV XLPE CABLES

1.1 SCOPE:

This specification covers the design, manufacturing, testing and supply of Heat- Shrinkable type cable straight-through joints and cable end termination kits as per IS:13573(Pt.2)/2011 suitable for use with and installation on 33 KV and 11 KV XLPE aluminum conductor cables .

1.2 The cable accessories specified in this specification i.e., cable end terminations,

either indoor or outdoor, and straight- through, shall be complete in all respects. Such complete set of accessories shall be termed as kit hereinafter in this specification.

1.3 Termination and jointing kits shall be heat-shrinkable type of proven make and

of a design and type which have already been extensively used and fully type tested. The offered kits shall be easy in handling and simple to install without much skill , with minimum tools at site.

2.1 TYPE

2.2 Termination Kits & Joints shall be heat shrinkable type for 33 KV & 11 KV XLPE

cables suitable for Outdoor and Indoor Cable End Terminations and Straight Through Joints

2.3 It is not the intent to specify completely herein all the details of the design,

manufacture & assembly of cable accessories; however, cable accessories shall confirm in all respects to a high standard of design & workmanship and be capable of performing in continuous commercial operation upto bidders guarantee in a manner acceptable to the purchaser, who will interpret the meanings of the drawings and specifications and shall have the power to reject any works or material which in his judgment are not in accordance therewith. The cable accessories offered shall be complete with all components necessary for the effective and trouble- free operations. Such components shall be deemed to be within the scope of supplier's supply irrespective of whether they are specifically brought out in this specification and/ or in the commercial order or not.

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2.4 SYSTEM PARAMETERS

1. Nominal operating voltage 33 kV rms 11 kV rms 2. Maximum system voltage : 33 kV rms 12 kV rms 3 Frequency (Hz.): 50 +/- 1.5 50 +/- 1.5

4. Number of Phases 3 3 5. Type of Earthing Solid Solid 6. Environmental conditions Humid Tropical Climate with polluted

atmosphere ,and/or , direct burial in water- logged ground.

7. Basic Insulation Level 170 kV (Peak) 75 kV (Peak)

2.5 SERVICE CONDITIONS

(A) The cable accessories to be supplied against this specifications shall be suitable for continuous & satisfactory operation under climatic conditions listed below:

S.No. Particulars

i) Peak ambient air temperature in shade (C) 50C ii) Minimum ambient air temperature (C) 0C iii) Maximum avg. ambient temp. over 24 Hrs. in shade (C) 40C

iv) Maximum temperature attainable by an object 60C V) Maximum relative humidity (%) 100 % vi) Maximum altitude above mean sea level 1000 mtrs vii) Maximum wind pressure (Kg./Sq.Mtr.) 100 viii) Number of months of tropical monsoon conditions 4 months ix) Average No. of rainy days per annum 100 x) Average Annual Rainfall in cms. 10 to 100

(B) The kits shall be provided with protection against rodent and termite attacks.

2.6 DESIGN FEATURES.

The following considerations shall be taken into account in the design of the product, material properties and the components of the jointing and termination kits.

i) Electrical stresses at the screen cut back in case of XLPE cables shall be

controlled to a safe value. The stress control may be either through stress control tubing / stress control cone or other suitable means. The bidder shall

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furnish details of the technique employed by them for stress control in cable- end terminations / straight-through joints. The application of stress control system shall be safe, foolproof and independent of cable jointers’ skills. The stress control method used should withstand expansion and contraction of the cable during load cycling.

ii) The cable end termination and jointing kits shall be so designed so as to prevent

discharge/ leakage at the cut back and nicks / scratches on XLPE insulations. Full details of the method of discharge prevention shall be indicated by the bidder in their offer.

iii) The cable end termination and jointing kits shall be so designed so as to give

track - resistant erosion and weather resistant protection to the cable insulation. The outdoor end terminations and straight through joints shall be totally sealed against ingress of moisture of environment.

iv) All Outdoor End Termination kits as well as 33 kV Indoor End Termination kits shall be

provided with rain (weather) sheds or creepage-extending petticoats. These shall be non-tracking , weather resistant, hydrophobic and have smooth surface to deflect any water/ dirt etc. The design of these rain (weather) sheds or creepage- extending petticoats shall avoid any shed to shed conducting path under heavy rain conditions.

v) The cable end terminations & jointing kits shall be class 1 as defined in IEEE

standard 48/1996 with latest amendments. Documentary proof shall be required to prove compliance in this regard without which the bid may be ignored.

vi) The lugs and ferrules provided should be suitable for compacted conductors and

should withstand thermal short circuit of 250 deg. centigrade.

2.7 GENERAL REQUIREMENT FOR CABLE END TERMINATIONS / STRAIGHT-

THROUGH JOINTS.

i) The term heat shrinkable refers to extruded or moulded polymeric materials

which are cross linked to develop elastic memory by irradiation method and supplied in expanded or otherwise deformed sizes/ shapes, subsequently heating in a strained state to a temperature above the shrink temperature resulting in the material recovering or shrinking to its original shape.

ii) (a ) The stress control tubes used in heat shrinkable cable accessories shall have

volume resistivity of minimum 1,00,00,000 ohm meters for both terminations & straight through joints. The relative permittivity shall be minimum 15. Bidder shall furnish documentary evidence confirming adherence to these along with the offer. Further, impedance of stress control tubes shall not change over a range of

105

temperature from 0 C to 125 C. The stress control tubes must have a thermal endurance equivalent to 35 years life. The impedance should also remain constant in spite of the difference in stress which will exist within the sleeve due to heating effect within the conductor and the temperature of the environment.

b) Bidder must submit graph showing effect on the impedance value of stress

control tube due to effects of stress, temperature variations and thermal ageing of minimum 10,000 Hrs. with the offer.

c) Copies of test reports on the critical components used in the joints & terminations

be furnished as per as per IS:13573(Pt.2)/2011, be furnished along with the offer. iii) The heat shrinkable polymeric material to be used for external leakage insulation

between the high voltage conductors and grounds should be non-tracking, weather and erosion resistant and hydro-phobic in nature. A heat-shrinkable flexible polymeric tubing, preferably coloured red, and possessing non-tracking erosion and weather resistant properties shall work as an external covering for the cable covers.

Rain - Sheds (skirts) provided should be of same material as the non-tracking tube specified in the paragraph above. Copies of test reports, confirming the non-tracking tubes and rain-sheds (skirts) meeting the above requirements shall be furnished along with the offer.

iv) Since the sealants or adhesives to be used between the heat shrinkable materials

and XLPE cable shall be exposed to high electrical stresses, they must be track resistant. Documentary evidence shall be furnished in this regard along with the offer.

V) All cuts/ nicks inadvertently occurred to XLPE insulation must be rendered

discharge free by using suitable discharge suppression compound.

vi) The heat shrinkable tubes may be either extruded or moulded type.

vii) The higher wall-thickness of heat shrinkable tubes / sleeves shall be preferred to counter the effect of erosion due to pollution.

2.8 OTHER REQUIREMENTS

i) The kit shall be suitable for storage without deterioration at a temperature upto 50

Deg. C and shall have unlimited shelf life. Conducting paints having limited shelf life are not acceptable.

ii) Proper stress control, stress grading and non tracking arrangement in the

termination shall be offered by means of proven methods, details of which shall

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be elaborated in the offer. Detailed sectional view of assemblies shall be submitted along with the offer.

iii) The straight through joints shall be suitable for underground buried installation

with incorporated back-fill and chances of flooding by water. The straight through joints should be absolutely impervious to the entry of water. The manufacturer shall use proven technology and design to prevent entry of water or any other liquid inside the straight through joints and cables.

iv) The end termination kits shall provide for total environmental sealing of the cable

crutch and at the lugs end. The details of the environmental sealing provided shall be submitted along with the offer.

v) Provisions for effective screening over each core shall be made and the bidder

shall categorically confirm this aspect in the offer. vi) The materials and components not specifically stated in the specification but

which are essential for satisfactory operation of the cable shall be deemed to be included in the kit without any extra cost.

vii) The terminations / joints shall be of better tracking resistant properties and fully reliable earthing system to maintain continuous contacts with screening/ armouring as the case may be.

viii) The armour / earthing arrangement shall form part of the terminations/ joints and shall be protected from erosion either by suitable tape or tube.

ix) The terminations/ jointing kits shall have provision for shield connection and

earthing whichever required.

x) The fault level as well as duration withstand capacity of termination / jointing kits

should be strictly matching with the parameters of cables for which the kits are intended to be used.

xi) The trade / brand name of the manufacturer, shall be embossed / engraved or suitably marked with indelible ink / paint for the purpose of identification on the tubings and components which are visible from the outside. The words “JVVNL” along with the trade / brand name of the manufacturer, TN No. , month / year of manufacture, size etc. shall be suitably printed / marked on the kit packing/Cartoon

xii) Suitable creepage extension/ rain protection sheds for outdoor cable end

terminations shall be provided.

xiii) Adequate provisions for eliminating the chances of entrapment of air at steps

formed by semicon screen shall be made.

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xiv) The terminations/ joints shall be supplied in kit form. All insulation and sealing materials, consumable items, conductor fittings, earthing arrangements and lugs etc. should be provided .

xv) The bidder shall furnish the constructional features of material offered.

xvi) An instruction manual in English and , optionally in Hindi script, indicating the

complete method/ proceedings adopted for installation of kits, preferably with more diagrams/ pictorial presentation shall be supplied with each kit. Various items, quantity thereof included in each kit must be indicated in the instruction manual / packing slip provided in the kit packing.

2.9 CABLE SIZE AND ITS REQUIREMENT

If the design of the cable jointing kits is such that same kit is suitable for more than

one of the cable sizes mentioned at clause 3.06 , then the bidder shall furnish the details of kit number and corresponding cable sizes for which the kit is suitable.

2.10 CIRCULAR SHAPED CONDUCTOR:-

The terminations/ jointing kits offered shall be suitable to be used on circular

compacted XLPE cable conductor.

2.11 LUGS/ FERRULES

Requisite number and size of lugs/ ferrules depending upon the type of the cable

shall be provided in the kit. Lugs and Ferrules shall be of crimping type , shall confirm to the relevant standards in case of XLPE cables.

2.12 EARTH/SCREEN CONTINUITY

i) Screen continuity by using tinned copper mesh and earth continuity by tinned

copper braids of appropriate size shall be provided for transfer of screen/ earth in straight through joints.

ii) Tinned copper braids of appropriate size along with copper lugs of proper size shall be provided for the continuity of screen/ armour along with adequate clamping arrangement.

2.13 EARTHING

Earthing shall be as per relevant standards and the details of the earthing

arrangement offered for the cable accessories shall be submitted along with the offer.

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2.14 FIRE RESISTANCE

The cable end terminations and straight-through joints shall be fire resistant.

The components of kits shall have flame retardant property.

2.15 INTERCHANGEABILITY

The components of different size of the kits shall be interchangeable between more

than one cable sizes in case the need so arises. Bidders should indicate the range / limits of such interchangeability.

2.16 EASY INSTALLATION

The bidder shall offer complete material and components for each kit so as to

make one termination/ joint complete in all respects. The bidder shall indicate the list of the material/ components with the supplied quantities of each for each type of cable end termination and straight-through joint.

i) The detailed bill of material and installation instructions shall be provided with

each kit for verification by the purchaser's inspecting officer and at Nigam's stores / site.

ii) All components shall be sealed separately and marked clearly for the purpose of

identification of each component. All components shall be supplied in a single package as a complete kit for one termination/ joint and shall bear the manufacturer's name and the cable size or range of cable sizes for which the kit can be used.

2.17 SUPERVISORY ERECTION & COMMISSIONING

The successful bidder shall provide free services of a trained jointer / foreman /

erector ( hereinafter referred to as jointer ) for installation / jointing all 33 kV cable end terminations and straight-through joints. The jointer of the supplier shall be duly trained and certified by the manufacturer for supervision of installation of the cable accessories. The jointer shall direct the sequence of installation. The jointer shall correct in the field any errors, omissions on the part of the bidder, in order to make the equipment and material perform properly in accordance with the intent of this specification. The jointer shall be responsible for any damage to the accessory during his work as well as for any damage resulting from faulty or improper installation. The purchaser shall provide adequate number of skilled / semi- skilled workers as well as all ordinary tools and consumable T&P items used in the work such as LPG gas / kerosene. The purchaser shall not be responsible for any other expenses such as erector's insurance against

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personal injuries to the jointer etc. Special tools such as LPG torch, if required for jointing, erection and commissioning , shall be provided by the supplier at his cost.

2.18 GUARANTEED & OTHER TECHNICAL PARTICULARS

(A) The bidder shall furnish the guaranteed and other technical particulars of the kits (B) The bidder shall highlight the various technical aspects and salient features of the

kits offered by them.

2.19 TESTS

1) TYPE TESTS

a) The bidder shall furnish valid and authenticated type test certificate as per

IS:13573(Pt.2)/2011 from a Govt. approved/ a Govt. recognized/ NABL accredited laboratory/ ILAC i.e. International Laboratory Accredited laboratory / ILAC i.e International Laboratory Accrediation Cooperation ( In case of foreign laboratory)

b) The bidder should furnish documentary evidence in support of the laboratory whose

type test have been furnished, that the said laboratory is a Govt/ a Govt. approved/ a Govt. recognized/ NABL accredited laboratory/ ILAC accredited ( in case of foreign laboratory)

c) Such type test certificates should not be older than Seven years as on the

date of bid opening.

d) Bids not accompanied with requisite type test(s) certificate not older than Seven years as on the date of bid opening, shall be treated as non- responsive.

2) ACCEPTANCE TESTS

A) The following tests shall constitute as Acceptance tests:

(i) Visual examination

(ii) Verification of bill of material / kit contents. (iii) Dimensional check including verification of lengths of tubes as given in the

GTP. (iv) Tensile strength (v) Ultimate Elongation (vi) Longitudinal shrinkages (vii) Dielectric strength (viii) Volume Resistivity

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(ix) Torchability / Recovery -as per manufacturer’s standard (x) Tracking Resistance ( as per ASTM 2303 )

The above tests shall be carried out in the presence of the Purchaser's

representative as per relevant prescribed standards , latest amended and the sampling plan shall be 1% subject to minimum of one No. of assorted size/type for each voltage rating i.e. 33 kV and 11 kV separately.

3) ROUTINE TESTS

The bidder must specify the details of the routine tests being conducted at their

Works along with the standards applicable in their offer.

2.20 INSPECTION

The supplier shall provide the facilities to carry out the prescribed acceptance tests

on selected samples from the lot offered at one or more testing laboratories. The samples from the lot shall be selected by the inspecting officer or the person authorized by purchaser.

All the tests shall be arranged and carried out as per the procedures laid down in

respective specifications as per latest amendment in the presence of purchaser's nominee.

The suppliers should satisfy themselves that the material offered are in

accordance with the term of contract and fully confirms to the required specifications by carrying out a thorough pre-inspection of each lot before offering the same for inspection to the purchaser. Such pre-inspection on the part of the supplier shall minimise the chances of rejection during inspection.

2.21 LIST OF KIT CONTENTS

The bidder shall furnish the lists of kit contents and shall also confirm unlimited shelf-life of the kits.

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TECHNICAL SPECIFICATION FOR GALVANISED STEEL STAYSETS OF SIZE 16X1800MM AND 20x2400 MM

1.1 SCOPE

This specification covers the design, manufacture, inspection, testing before

dispatch, supply and delivery F.O.R. destination anywhere in Jaipur Discom of hot dip galvanized steel stay sets of size 16x1800 mm and 20X2400( oiled threads) with G.S. Anchor plates, as per pattern-1 of BS:16/1974.

1.2 Size 20X2400 mm

Hot dip galvanised steel stay sets of dia 20mm, 2400 mm long (oiled threads

complete with ratchet nut, GS anchor plates size 380x380x4 mm ( having square hole size as 22 x 22 mm in centre) & fitted with cast iron cross head and steel bow dia 14 mm conforming to pattern-1 of BS:16/1974

1.3 Size 16X1800 mm

Hot dip galvanized steel stay sets of dia 16mm, 1800 mm long (oiled threads

complete with ratchet nut, GS anchor plates size 300x300x4 mm ( having square hole size as 18 x 18 mm in centre) & fitted with cast iron cross head and steel bow dia 12 mm conforming to pattern-1 of BS:16/1974


The hot-dip galvanized steel stay sets and anchor plates shall strictly conform to

BS:16/1974 with latest amendments thereof as per pattern-1 in all respect, except herein otherwise stated. The ratchet nut and the cross head bow shall be having three (3) cuts in place of six(6) . The dimensions of the cross head portion of the bow of each type of stay set shall be as per the drawing enclosed at Appendix-A (i) & (ii). Tolerances in dimensions shall be governed by the values appearing at Schedule of GTP.

The stay sets shall have galvanizing as per BS:729/1961 part-I with latest amendments thereof and shall be galvanized by hot dip galvanization process.


i) The rod and bow shall be free from flaws and other defects, shall be of good

finish and the cross head shall not fail, draw and deformed when the assembly is tested to fracture as their full section by tensile strength. The ratchet nuts and ratchet face of each cross head shall be well formed, so that any nut and any cross head of the appropriate size shall provide good ratchet action. The treads of stay sets shall be cut after galvanising and shall be lubricated with good quality of mobile oil to prevent rusting.

(ii) The rods and bow shall be of steel suitable to give strength as per table of tensile

strength as at 5.2(a) below:

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(iii) The cross head may be made of forged mild steel/ hot rolled steel. The ratchet nuts

shall be of steel or malleable cast iron.

(iv) The side of each bow shall be well riveted into the cross head ( sound/strong iron casting) & shall not draw when the complete assembly is tested to fracture by tensile stress.

(v) In case of galvanized steel stay sets & anchor plates, all the ferrous metal parts shall be smoothly & continuously hot dip galvanised with zinc, the nuts shall have neat fit so that they can be turned easily through out the length of the threads on the bolts & nuts shall be capable of developing the full strength of the bolts. The galvanising shall satisfactorily withstand the test specified BSS:729/1961 Part.I with latest amendments.

(vi) The parts of stay sets of the same type shall be strictly interchangeable.

(vii) The steel anchor plates shall be clearly cut off and punched and shall be free from cracks after punching.

(viii) The rods, bows and plates shall strictly conform to table 3 and 6 of BS:16/1974 (

stay rods No.13 M & 15 M & anchor plates No.23 M1 & 45 M1) in respect of dimensions etc. and figure 4& 5 (Pattern-I) in respect of shape etc. The dimensions of the cross head portion of the bow shall be as per the drawing enclosed at Appendix-A of this section.

4.1 TEST :

4.2 TEST BEFORE DESPATCH :

The G.S.Stay Sets and accessories shall be subjected at manufacturer's works before

dispatch to the following test(s) as per BS/IS.

A) ROUTINE TEST ON EACH UNIT AS PER RELEVANT STANDARD :

The dimension of the stay rods, bows and plates shall strictly conform to table 3 and 6 of BS-16/1974 (Stay rods No.13 M & 15 M and anchor plates No.23 M-1 & 45 M-1) in respect of dimensions etc., and fg. No.4 & 5 (Pattern-1) in respect of shape etc. the dimensions of cross head portion of the bow shall be as per drawing

4.3 ROUTINE / ACCEPTANCE TEST :

The following tests shall be got conducted in presence of Purchaser's representative.

a) TENSILE TEST :

The finished stay sets when subject to tensile test shall comply with the requirement of the tensile strength as per the table given below:

S.No. Diameter of rods Breaking load 1. 20 mm 96 KN 2. 16 mm 62 KN ( 1 KN = 101.972 Kgf)

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b) HOT DIP GALVANISED TEST :

The finished stay sets when subject to dip test in standard copper sulphate solution for the testing of galvanization quality should be able to witnessed four dips of one minute each as per BS:729/1961 Pt.I with out any copper deposits on the surface.

The weight of zinc coating should not be less than 610 grams per sq.m for rods

and 460 grams per sq.m for plates as per BS:729/1961 Pt.I. 4.4 SAMPLING PLAN FOR INSPECTION:

Since the sampling procedure/ plan has not been mentioned in the BS:16/1974,

the following sampling plan shall be applicable for inspection testing/ checking of the stay sets. (i) FOR TENSILE STRENGTH TEST : 1 out of 1000 Nos.

CRITERIA FOR CONFORMITY :

If one or more sample(s) fail, twice the number of samples originally tested shall be selected and shall be subjected to the test. If there is no failure among these samples, the lot or the sub lot shall be considered to have satisfied the requirement of this test. If one more sample(s) of the second sample fails, the lot or sub lot represented by the corresponding samples shall be considered not to have passed the test.

(ii) FOR PHYSICAL DIMENSIONAL CHECKING AND GALVANISATION TEST:

The sampling plan will be as under :

The lot offered for inspection, be divided in sub lot not exceeding 5000 Nos.

sets for each sub lot. Acceptance or otherwise of sub lot shall be determined on the basis of performance of the samples selected from it as per details mentioned as under :

Size of sub-lot Sampl

e size Sample size for re- inspection

Permissible Failure From Istsample size

From total samples including re- inspection

n1 n2 c1 c2 Upto 1000 2 4 0 1 1000 to 2000 4 8 0 1 2001 to 3000 6 12 1 2 3001 to 5000 10 20 1 3

4.5 CRITERIA FOR CONFORMITY

Sub lot shall be considered as conforming to the requirement of the acceptance test if the Nos. of failure found in first samples selected as per Col. No.2 of above table, are upto the No. mentioned in Col.4 If the No of failure is more than or equal to the sample mentioned in Col.5 lot shall be considered as not conforming to the requirement of acceptance and shall be rejected. If the No. of failure is between c1 and

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c2, a second sample of n2 stay sets shall be selected and subjected to acceptance test. If the number of failure in the two samples sizes (n1+n2) combined is less than c2, the lot shall be considered as conforming to the requirement of acceptance tests otherwise it shall be considered to have failed.

4.6 TOLERANCE ON TEST RESULTS :

As per BS:16/1974 and GTP of specification .

The purchaser reserve the right to conduct all test(s) on stay sets after arrival at site and the contractor shall guarantee tests certificate under actual service condition(s).

5.1 INSPECTION

5.2 All the tests (as mentioned at Clause 5.1 and 5.2) and Inspection shall be made

at the place of manufacturer unless otherwise especially agreed upon by the bidder and purchaser at the time of purchase. The bidder shall afford the inspection officer(s) representing the purchaser all reasonable facilities without charges, to satisfy him that the material is being furnished in accordance with this specification. The purchaser has the right to have the tests carried out at his own cost by an independent agency whenever there is a dispute regarding the quality of supply.

5.3 The Inspection may be carried out by the purchaser at any stage of manufacture/

before dispatch as per relevant standard. 5.4 Inspection and acceptance of any material under the specification by the

purchaser, shall not relieve the bidder of his obligation of furnishing material in accordance with the specification and shall not prevent subsequent rejection if the material is found to be defective. The Bidder shall keep the purchaser informed in advance, about manufacturing programme so that arrangements can be made for inspection.

5.5 The purchaser reserves the right to insist for witnessing the acceptance/ routine

testings of the bought out items. 5.6 The Bidder shall give 15 days advance intimation to enable the purchaser to

depute his representative for witnessing the acceptance and routine tests. The inspection charges would be to the purchaser's account.

6.1 DOCUMENTATION :

6.2 All drawing(s) shall conform to International Standard Organization (ISO) À'

series of drawing sheet / Indian Standards Specification IS:656. All drawing(s) shall be in ink and suitable for microfilming. All dimension(s) shall be in SI Units.

6.3 List of drawing(s) and documents :

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The bidder shall submit four sets of drawings, complete with fully dimensioned elevation, cross sectional and longitudinal section drawings of each type of material and its assemblies. All drawings shall be to scale with full details.

All important dimensions being given therein and the material of which each

part is made of shall be clearly indicated. The drawing of cross head portion and bow and tolerance in the dimensions as per this specification shall be forming a part of contract.

The manufacturing of the equipment shall strictly be in accordance with the

approved drawings and no deviation shall be permitted without the written approval of the purchaser. All manufacturing and fabrication work in connection with the equipment prior to the approval of the drawing shall be at the supplier's risk.

The equipment shall conform to high standard of engineering, design

workmanship and latest revisions of relevant standards at the time of ordering and purchaser shall have the power to reject any work or materials which in his judgment, is not in full accordance herewith.

7.1 MARKING:

Each bow of stay sets shall be provided with the following marking :

a) Name of Manufacturer or Trade Mark. b) IPDS/TN No………

The marking on bow should be embossed during the course of casting.

8.0 TEST CHECKING OF MATERIAL

The material received shall be subjected to the test checking at CTL before

final acceptance of the material, the procedure for the same shall be as under : 9.1 SAMPLING

One sample out of each sub-lot / lot consisting of following quantities or part thereof in case of each type of G.S. Stay Set from each inspected lot received in stores shall be selected for test checking of material and shall be got tested.

I. G.S Stay Set of size 16X1800 mm– 1000 sets. II. G.S Stay Set of size 20X2400 mm – 1000 sets.

The selection of sample from the material received at stores shall be done as soon as material is received in stores without the presence of the representative of the supplier. However, testing of sample(s) at CTL shall be carried out in the presence of representative of the supplier after identification / confirmation by him that sample so selected belongs to them. In case the supplier disputes that the selected samples does not

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pertain to them, then fresh sample shall be selected in the presence of the representative of the supplier and test(s) be carried out.

10.1 TESTS


a) Visual Examination, Verification of Dimension(s), weight and marking Test b) Tensile strength test. c) Galvanisation (Uniformity) Test.

10.2 Only those tests shall be conducted at CTL for which facility with CTL is available.


a)Visual Examination, Verification of Dimension(s), weight and marking .

As per specification/ ISS/ BIS

b) Tensile strength test.

In case of failure of sample in tensile strength test the material contained in the lot / sub-lot to which the sample belongs, shall be rejected. The rejected material shall have to be replaced by the supplier free of cost.

c) Galvanisation (Uniformity) Test.

i) The sample(s) shall be first tested for (n-2) number of dips where (n) is specified

number of dips in the contract. If the sample(s) does not pass the uniformity of Galvanisation Test for (n-2) dips, the material shall be rejected and the material relating to relevant lot / sub-lot to whichsample(s) pertains shall have to be replaced by the supplier free of cost.

ii) If the sample has passed the uniformity of Galvanisation Test for (n-2) dips,

then it shall be tested for (n-1) dips. If the sample has not passed the uniformity of Galvanisation Test with (n-1) dips, then material pertaining to relevant lot / sub- lot shall be accepted with a deduction @ 10% of cost of material.

iii) If the sample has passed the uniformity of Galvanisation Test with (n-1)

dips, then sample shall be tested for last one dip of one minute to complete the test for `n' dips. If the sample does not pass the uniformity of Galvanisation Test with `n' dips, then the material pertaining to relevant lot/ sub-lot shall be accepted with a deduction @ 5% of cost of material.

iv) If the sample(s) have passed the Test with number of dips as specified in the

contract (n), then material pertaining to relevant lot / sub-lot shall be accepted.

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11.0. TYPE TEST REPORTS :

11.01 The bidder shall furnish valid and authenticated type test certificates from a

Govt. approved / Govt. recognized / NABL Accredited laboratory / ILAC i.e. International Laboratory Accredited Laboratory (in case of foreign laboratory) of similar rating and design of tendered material/ equipment. Such type test certificates should not be older than 05 years as on the date of bid opening. For this purpose date of conducting type test will be considered.




11.4 The bids of only those bidders shall be considered to be meeting the type test criteria who furnishes complete type test certificate with the bid as per above provision.

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TECHNICAL SPECIFICATION FOR THE SUPPLY OF DANGER PLATES FOR 33/11 KV & 11/0.4 KV SUB-STATIONS

1.0 SCOPE

This specification covers the fabrication, manufacture, testing, checking & supply of Danger Label/ plates for 33/11KV & 11/0.4 KV Sub-Stations. Before despatch of material, the inspection testing & checking will be witnessed by the representative of the purchaser.

2.0 SPECIFICATIONS & STANDARDS:

The relevant ISS to which this material shall conform are indicated as below:-

S.NO. Bureau of Indian Standards Title

a) IS:2551-1982 ( Latest amended) For general checking b) IS-5-1978 ( Latest amended) For colours for ready mixed paints an

enamels.c) i. IS:3972 (Pt.2/Sec.1):1985 For resistance to citric acid at room

temperature and boiling temperature.ii) IS:3972 (Pt.2/Sec.1)1985 For low & high voltage tests for detecting

and locating defects.iii) IS:3972 (Pt.1)Sec.1):1982 For production of Specimen for testing.

3.0 DIMENSIONS:-

S. Items Nominal thick- Other dimension as per ISS No. ness of M.S. Length Width

Plate (Min.) in mm in mm.

1. Danger 1.6mm 250 200 Plates IS-2551/1982 (latest amended) for 33/11 KV & 11/0.4 KV Sub-stations.

4.0 Material

The Danger plates shall be made from mild steel sheet of at least 1.6mm thick

and vitreous enameled white with letters, figures and conventional skull and cross bones in signal red colour conforming to IS-5-1978 on the front side and rear side should be enameled black. The edges & rear side should be enameled black. Holders for fixing the plates should be drilled not punched.

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5.0 TESTS:-

In order to ensure that Danger plates conform to the specification the following tests are to be carried out:-

a) Visual Examination. b) Dimensional check including checking of thickness of M.S. Plate and weight. c) Test for weather proofness. d) Checking of thickness of enamel. e) Resistance to citric acid at room temperature. f) Low & high voltage tests for detecting and locating defects.

6.0 INSPECTION:-

The number of samples of danger plates selected at random from the lot shall be in accordance with the table given below:- Lot size

First sample for tests a,b,c, d,e & f.

sample size for checking of thickness of steel plate & enameling.

Permissible Rejection number.

Second sampling.

Permissible Rejection number

a) Upto 500 5 1 0 2 b) 501 to 800 7 2 0 3 c) 801 to 1300 10 4 0 3 d) 1301 to 3200 15 6 1 4 e) 3201 to 8000 25 8 2 5 f) 8001 & above 35 10 2 7

The checking of the thickness of M.S. plates and enamelling on the plates number of samples as per Column 3 is acceptable provided the rejection of the samples is not more than the number mentioned in column 4.

In the event of rejection being more than the number in Column 4 double the sampling

as per Column 5 be done. Incase of rejection of samples is beyond the number mentioned at 6, the lot shall be considered rejected.

On inspection/ testing/checking, if the material is found acceptable as per above criteria

the purchaser's representative shall seal the material, before dispatch.

7.0 MARKING

The essential information that would be necessary to identify the manufacture of Danger Plates such as JVVNL/TW/IPDS /TN No….. shall be marked in such a manner & position on the plates that it does not interfere with the other information and should be of permanent nature.

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8.0 TEST CHECKING OF MATERIAL AT TESTING LABORATORY:

The material received in nigam shall be subjected to the test checking at testing laboratory before final acceptance of material. The procedure for testing shall be as under:

i) SAMPLING One sample out of each sub lot/ lot of (1000 Nos.) thousand Nos. or part thereof from each inspected lot received in stores shall be selected from each store for test checking of material and shall be got tested. The selection of sample from the material received at stores shall be done as soon as material is received in stores without the presence of the representative of the supplier. However, testing of sample(s) at CTL or else where as arranged by the JVVNL shall be carried out in the presence of representative of the supplier after identification / confirmation by him that samples so selected belong to them.

ii) TESTS

The following test shall be carried out on the above samples :

a) Visual examination , verification of dimensions, weight and marking as per

GTP/ISS/Specification/ approved drawing.

iii) CRITERIA FOR ACCEPTANCE

Visual Examination, verification of dimensions, weight and markingas per Specification/ GTP/ ISS/approved drawing.

iv) TEST CHARGES :


shall be borne by the NIGAM except that of personal expenses of the representative of the supplier for witnessing the tests.

9.0 PACKING

You shall pack the material in the suitable wooden cases so that the material

may not be damaged in the transit and also remain protected from the atmosphere.

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TECHNICAL SPECIFICATION OF 36 KV INDOOR TYPE VACUUM CIRCUIT BREAKERS

1.1 SCOPE :

This specification covers the design, manufacture, assembly, testing at manufacturer's works before dispatch, supply, delivery of 3 pole, 50 Hz, 36 KV switchgear and control gear panels for indoor installation fitted with 36 KV vacuum circuit breakers including voltage transformers, current transformers, metering instruments, protection relays etc. The power system is with neutral solidly earthed. The equipment offered shall be safe, reliable and compact to install. The workmanship shall be of high order. The circuit breaker and protective devices shall be of latest design so as to ensure rapid and efficient interruption of fault current, low arc energy, small arcing time, complete phase segregation and freedom from fire hazards.

1.2 STANDARDS :

The circuit breaker/metal enclosed switchgear, Voltage transformers, current transformers and all other equipment shall also comply with the requirement of latest edition of relevant Indian standards. Deviation from the standards and this specification if any, should be brought out in the tender and justified. Voltage transformer and current transformers shall be mounted within the panels. The governing standard shall be :

S.

No.

IS/IEC Reference Specification

1. IEC-62271/ 100-200 High Voltage Switchgear & Control gear

2. IEC-298 A.C. Metal – enclosed and control gear for rated voltages above 1KV and including 72.5KV

3. IS-3427 A.C. Metal – enclosed and control gear for rated voltages above 1KV and including 52KV.

4. IS-8623 Specification for Low Voltage Switchgear and Control gear assemblies.

5. IS-13118

IEC-56

Specification for High Voltage AC Circuit Breakers.

6. IEC-529 Degrees of Protection.

7. IS-5578 & 11353 Marking and arrangement for switchgear bus bar main connections and auxiliary wiring.

8. IS-325 Specification for 3 Phase Induction motors.

9. IS-2629 Recommended practice for hot dip galvanizing of iron and

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steel.

10. IEC-137 Bushing for AC Voltages.

11. IS-3347 Porcelain Transformer Bushings.

12. IS-5561 Terminal Connectors

13. IS-3156 Voltage Transformers

14. IS-2705 Current Transformers

15. IS-3231 Electric relays for power protection.

16. IS-13010 -

17. IS-13779 Static Energy Meters

18. IS-8686 Static Protection Relays

19. IS-1248 Electrical measuring instruments

20. IS-2099 High Voltage Porcelain Bushings.

21. IS-10118 Minimum clearances for Outdoor Switchgear.

22. IEC-694 Common Clauses for High Voltage Switchgear and Control gear.

23. IEC-60255 &

IEC-61330

Numerical Relays

Equipments conforming to any other internationally accepted standard(s) which ensure(s) equal or better quality than the standard(s) mentioned above would also be accepted. In case the tenderers wish to offer equipment conforming to other standards or alternative offer which tenderer considers advisable by reason of his own manufacturing requirement and experience would be acceptable provided descriptive matter, literature and complete certificates are submitted pointing out that the equipment/devices/arrangements as offered are equal or superior to that required by the accompanying specification with full justification. They shall furnish English translation of the relevant standards where the equipment conforms to any other standards. Salient points of difference between the standards adopted and those mentioned above shall be brought out.

1.3 a) PARTICULARS OF SYSTEM :

i) Nominal system voltage : 33 KV ii) Highest system voltage : 36 KV iii) Frequency : 50 Hz iv) No. of phases : 03 v) Neutral earthing : Effectively earthed

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b) SERVICE CONDITIONS :

The equipment should operate satisfactorily under the climatic conditions specified in this specification. The reference maximum ambient Air temperature may be taken as 50 Deg. C. as against 40 Deg. C. The permissible temperature rise for various equipments offered should therefore be derated accordingly.

1.4 PRINCIPAL PARAMETERS

1.3.1 IRCUIT BREAKERS :

a) Rating and characteristics of circuit breakers :

1. No. of poles 3 2. Class : Indoor 3. Rated voltage : 36 KV 4. Rated insulation level a) Light-ning impulse voltage : 170 KV (Peak) b) One minute power frequency : 70 KV (rms)

withstand voltage. 5. Rated frequency : 50 Hz 6. Rated normal current : 800 A 7. Short circuit breaking capacity : 25 KA 8. Short time withstand current : 25 KA

for 3 secs. 9. Protection class : IP 5X 10. Maximum opening time : Less than 3 Cycles 11. Rated operating sequence : O-0.3 Sec.-CO-3min-CO

12. Minimum operations at full 100

rated short circuit breaking current.

13. Rated Breaking Capacity i) Symmetrical : 25 KA ii) Asymmetrical : As per relevant Standards

14. Rated making capacity : 2.50x25 KA 15. Operating Mechanism : Motor operated Spring charged closing

mechanism. 16. Heater/Lamp/Socket : 240 V A/C

17. Control Voltage : 110V DC

b) Characteristics of the operating mechanism of Circuit breaker

and associated equipment : i) Method of operation : The circuit breakers shall be equipped with power operated

mechanism to operate all the three phases simultaneously using 220/240V universal motor operated spring closing mechanism. The circuit breakers shall

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also be provided with hand operated spring closing mechanism. The Circuit Breaker shall have electrical and mechanical tripping arrangements under various conditions. In case of spring closing mechanism no main spring of the mechanism shall be plated, powder coated or given any other treatment so that spring property is not lost.

ii) Number and type of spare, auxiliary switches : Adequate number of spare

auxiliary switches/ contacts both of normally open and normally close type but not less than eight each shall be provided on the circuit breaker for use in the indication and controlling scheme of the circuit breaker.

vii) Rated supply voltage and rated supply frequency : The rated voltage for the

auxiliary supply shall be 240 V, 50 Hz AC supply. 1.3.2 DESIGN CRITERIA

The bidder shall quote 36 KV Indoor type Vacuum Circuit Breakers conforming to M-2 class only. The equipment will be used in high voltage system having characteristics as listed in the specification. The equipment will be installed indoor in a hot, humid and tropical atmosphere.

All equipment, accessories and wiring shall have tropical protection, involving special treatment of metal and insulation against fungus, insects and corrosion.

The maximum temperature in any part of the equipment at specified rating shall not exceed the permissible limits as stipulated in the relevant standards and this specification.

The equipment shall be capable of withstanding the dynamic and thermal stresses of listed short circuit current without any damage or deterioration.

The safety clearances of all live parts of the equipment shall be as per relevant standards.

1.3.3 CONSTRUCTIONAL FEATURES :

a) The circuit breakers shall be triple pole metal clad truck mounted horizontal

drawout type enclosed in cubicle made of CRCA sheet steel of minimum 3 mm thickness and shall comply with latest edition of relevant IS. The cubicle/ panels shall be vermin proof and dust tight. The cubicle shall be of folded type construction. The switchgears and control gear shall be complete with all necessary supporting frame work, nuts and bolts etc. for securing the same to the floor. The operating mechanism shall operate (close/open) all the three phases simultaneously. The operating mechanism, links etc. should be accessible for maintenance. Mechanical safety shutters should be provided between breaker and panel. Engagement and disengagement of auxiliary supply should be automatically linked through the movement of the truck so that in service condition auxiliary supply is automatically made. All six terminals shall brought out of cubicle through appropriate class of cable termination and sealing kits. All the breakers shall be

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supplied with necessary clamps suitable for appropriate current ratings. Suitable arrangement of earthing on the switchgear and control gear panels shall be provided. The arcing contacts shall be made of homogeneous special alloy so that surge voltages are reduced to negligible level and multiple arc reignition is eliminated. All the connecting bus bar & current carrying parts shall be made of copper for these indoor circuit breakers.

b) For indoor panels, SWITCHGEAR (circuit breakers, CTs, PTs etc.) and control

gear (relays, meters etc.) shall be mounted on the same panel. A set of air insulated electrolytic copper bus bars having maximum current density 1.5 Amp./ mm2 with minimum cross sectional area of 720 mm2 with PVC sleeves or PVC insulation are to be provided for all indoor switchgear panels. The switchgear panels shall be provided with the arrangement for extending the bus bar and interconnecting bus bars. Their supports, nuts and bolts etc. will be supplied loose. The region of such inter connection shall normally be blanked on panels. The bus bars should be of electrolytic copper with permissible limits of current density. Size of the bus bar and current density should be specified in the tender. The bus bar conductor shall conform to IS:8034. The bus bar shall be rated for 25KA for 3 Seconds.

c) The following safety interlocks & features are required to be provided in the

breaker:- 1) For VCB Chamber

i) Rack in Operation from Test to Service:-

It should not be possible to rack in the VCB Truck unless & until the VCB is in switched off condition, VCB chamber door is closed, LV Control plug is connected & locked and the Cable earthing switch (if provided) is switched off.

ii) Rack Out Operation from Service to Test:-

It should not be possible to rack out the VCB Truck unless & until the VCB is in switched off condition.

iii) For earthing switch in cable chamber:

It should not be possible to operate the earthing switch unless & until the respective VCB Truck is in test condition.

iv) The movement of VCB shall be duly interlocked so that it can not be racked in to service position in pre closed condition & it is not possible to rack out from service position in pre closed condition. Any attempt to close the VCB into intermediate position shall be blocked by sustained mechanical tripped command overriding on to the mechanism to avoid closure of the contacts of VCB. Any attempt to cause the movement of VCB shall initiate the tripping of a VCB and only thereafter the movement shall be facilitated.

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v) The mechanism shall be trip free type with inherent capability of O-CO operation.

vi) The Circuit Breaker should be designed in such a manner that there should be proper metal compartmentalization of the various circuit breaker parts such as breaker chamber, Bus bar chamber & Cable chamber.

vii) Test and service position limit switches shall be provided. viii) The provision should be made to avoid accidental contact & access to the

high electrically stressed area by providing appropriate touch to safe metal screens when the VCB is posed into service position inside the cubical.

ix) No separate VCB handling trolley shall be required to insert the VCB inside the panel. The VCB shall be floor rolling type.

x) The VCB should be provided with proper interlock for the secondary isolating plug & socket type contacts so that it is not possible to insert the VCB from the test to service position unless the secondary plug socket is connected & it is not possible to remove the secondary plug socket into intermediate position & in service position.

xi) The insulation used shall be non hygroscopic & non deformable type and it should be free from any partial discharge when exposed to sustain over voltages.

xii) The VCB shall be completely type tested as per IEC 62271-100/200 or ISS. xiii) The operating instruments like switches etc shall be placed at height less

than 1900mm. xiv) The total height of the panel should not exceed more than 2700mm and

width should not exceed 1200mm. xv) The panel should be designed totally on air clearances basis with no

dependency on the external shrouds & add on insulations. xvi) The panel shall have epoxy spout insulators between the bus bar & VCB

chamber to have proper compartmentalization. xvii) The bus risers shall be epoxy coated and should be integral part of the spout

bushings. xviii) Entire bus bar compartment is provided with solid insulation scheme to have

less dependency on the inter phase barriers. xix) The panel shall have rigid sheet steel construction for better stability and

shall be self standing without the external bracings. xx) The panel should be designed to have gravity operated self resetting type

pressure relief flaps to have internal arc fault proof design. xxi) The panel should have integral foundation frame. xxii) The CT’s shall be top terminal CT’s and mounted on the panel base frame to

facilitate easy mounting and serviceability. xxiii) Adequate cable termination space of around 700mm shall be provided with

facility to terminate 3 cables of 3CX400 sq. mm size. xxiv) Panel should be provided with independently operated, insulated type non

metallic shutters with pad locking facility. The shutters shall automatically operate with the VCB trolley movement.

xxv) The multi-core cable entry should be provided optimally from front or rear side of the panel. The necessary arrangement of cable entry from Left Hand/ Right Hand side through self standing side cable boxes should also be made.

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xxvi) Hinges of door shall be consealed type to avoid rusting and obstructive opening of the door.

xxvii) The quality of welding shall be good and there should not be any lumps and splatters on the panel”.

xxviii) All the gasket shall be of chemically treated neoprene. xxix) Hole & Pin locking (Check nut) arrangement should also be provided while

fixing the vacuum interrupter at bottom side.

1.3.4 VACUUM CIRCUIT BREAKER : The three phase vacuum circuit breakers will have three interrupters (one interrupter per

phase) mounted on same carriage. The interrupters shall be air insulated in epoxy resin tank or with epoxy resin phase barriers. Each interrupter shall have fixed and moving contacts in sealed envelope having vacuum below 10-6 torr. The metallic bellow shall permit axial movement of moving contact and act as vacuum seal. The contacts shall have requisite mechanical strength and good electrical and thermal conductivity and shall be made of copper chromium alloy. Complete literature of vacuum bottles shall be furnished with the tender.

The vacuum interrupter should be housed in epoxy pole unit and make of Vacuum Interrupter should be BEL, CGL, SIEMENS, ABB & ALSTOM /AREVA, MEGAWIN only.

1.4 VOLTAGE TRANSFORMERS :

1. Highest equipment voltage : 36 KV 2. No. of phases : 3 3. Insulation level a) Impulse withstand voltage : 170 KVP b) One minute power frequency

withstand voltage on : i) Primary winding : 70 KV rms ii) Secondary winding : 2 KV rms

4. Frequency : 50 Hz. 5. Transformation ratio : 33000/110 V 6. Rated output : 30 VA / phase 7. Accuracy class : 0.5 8. Winding connection : Star/Star 9. Rated voltage factor : 1.2 continuous and 1.5 for 30 seconds 10.Type of insulation : Resin cast

VTs shall be provided with HRC type fuses on the secondary side. The VT fuses on primary side shall also be provided with all safety precautions. One of the secondary terminals of the VTs shall be solidly earthed. The panel shall be provided with draw out of 3 Nos. Single Phase Voltage Transformers.

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1.5 CURRENT TRANSFORMERS :

1. Rated voltage : 36 KV2. Insulation level

a) Impulse withstand : 170 KVP

voltage b) One minute power

frequency voltage on i) Primary winding :

70 KV rms

3.

ii)Secondary winding :Frequency :

03 KV rms50 Hz

4. Rated continuous thermal : current

120% of rated primary current

5. Short time thermal rating : 25 KA for 3 Sec.

6. Transformer CTs of ratio : 400-200/5-5A. 7. Rated output/accuracy etc. for CTs.

Core-I Core-II a) Rated output

30 VA 15 VA However VA burden should not be less than suitable for A.C. series trip requirement with shunt trip arrangement.

b) Class of accuracy 5P 0.5 S c) Accuracy limit factor 15 - d) Purpose Relaying Metering

8. Max. instrument security - 5 factor

9. Type of Insulation Resin Cast

36 KV current transformers shall be single phase. The core shall be of high grade non ageing laminated silicon steel of low hysterisis loss and high permeability to ensure high accuracy for both normal and fault current.

1.6 The rating of secondary winding shall be 5 Amps. However, the current transformers

will have to satisfy the requirement of rated VA burden, class of accuracy, accuracy limit factor and short time thermal rating as have been specified in clause No. 3.5 at all transformation ratio. Magnetization curves corresponding to all secondary taps must be submitted with the tender.

The ratings of current transformers of all classes regarding ratio error, knee point voltage, resistance of secondary winding etc. shall have to be co-ordinated with the requirements of protective relays and protection scheme, without any extra cost.

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1.7 Before commencement of supplies one No. panel with circuit breaker, VT etc. will have to be subjected to temperature rise test without extra charges in the presence of our Inspecting Officer.

1.8 The tenderer shall also furnish along with the tender, complete general

arrangement, schematic and outline diagrams indicating the mounting arrangement and position of current transformers, voltage transformer terminal blocks etc. Type of current transformer and voltage transformer employed shall also be clearly stated.

1.9 INDICATING AND INTEGRATING METERS/INSTRUMENTS :

1.9.1 All indicating instruments shall be of switchboard type, back connected, suitable for

flush mounting and provided with dust and vermin proof cases for tropical use and finished in suitable colour. All instruments shall have practical laboratory means for adjustment of accuracy. Only analog type indicating instruments shall be acceptable. The limits of errors for ammeters/voltmeters shall be those permissible for class 1.0 or better instruments as per IS:1248. The ammeters and voltmeters shall be suitably scaled to indicate the current/voltage for all the rating of current/voltage transformers. A phase selector switch with four/six position shall be used to measure the current/voltage of each phase/line. The meters shall be located at eye level to facilitate observation of readings correctly.

1.9.2 A.C. Static HT Trivector Meter :

3 phase 4 wire A.C. Static H.T. Trivector meter of accuracy class 0.5S for measurement of energy as per latest specification of JVVNL with DLMS protocol, shall be provided on each Outdoor VCB Kiosks.

Following makes of HT TVMs are acceptable:

i) Secure

ii) L&T

iii) ABB/Elster

iv) Schlumberger

v) Genus Infra

Any other make being procured by Nigam shall also be acceptable. 1.10 RELAYS :

The circuit breaker shall be fitted with shunt trip coil for operation on Numerical

Over Current and Earth Fault relay. The coils should be rated for 110VDC operation on station battery.

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Three phase protection relays shall be Numerical Over-current & Earth Fault protection having 3 element for over current and one for earth fault protection with instant trip. The setting for over-current shall be 50-200% (continuous range) and for earth fault element from 5 to 80% (continuous range). These relays shall be non directional with selectable curve for all standard IDMT curves. The numerical relays shall have following features:-

i. Self Diagnosis ii. Minimum last five abnormal events recording (over current & earth fault)

indicating fault current and phase, along with Date & Time. iii. On-line display of current. iv. Communicable with open Protocol having RS-485 port. v. Instantaneous Over-Current Protection with adjustable timer.

vi. Breaker Failure detection.

vii. In-built Circuit Breaker Trip Circuit Supervision function during pre closing

and post closing of Circuit Breaker.

viii. DC supervision.

ix. Very low burden on CT (less than 0.5VA)

x. Continuous monitoring of module’s internal hardware and alarm

generation in case of failure of any critical components.

xi. 5 Digital Output contacts for local alarm as well as tele-signalling.

The relay shall be numerical type mounted in flush pattern on the panel board. The

relay should be rated for 5 Amp. CT secondary. The relay should conform to relevant ISS. The tenders shall furnish the detail in this regard along with the offer.

All the relays shall be provided with test blocks in panel so designed that the relays may be tested in situ. The relays should have provision of testing either through test block or test plug easily accessible by injecting the voltage / current/frequency (as applicable) from external testing instruments /source without first disconnecting/ reenergizing the primary electrical circuit protected by the relays. Facilities for isolating the tripping circuit during such testing shall also be provided.

Relay TTB shall have trip bypass arrangement.

The requirement of test block shall not be applicable in case of drawout type relays which can be tested by using test plug without removing the relay from its casing.

The testing facilities provided in the relays shall be specifically stated in the bid. One test plug with five panels or part thereof are to be supplied.

The Following makes of Relays are acceptable:-

a. Areva. f. JVS b. ABB. g. SEL c. Easun Reyrolle h. ASHIDA

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d. C&S i. MEGAWIN e. Crompton j. Stelmec

The technical suitability of relays/schemes may also be examined by Protection Wing & acceptability will be judged appropriately.

The bidder must furnish type test reports as per relevant ISS/ IEC along with bid to

suit the environmental conditions of our State, in respect of the relay (of the type and design offered) which should have been type tested in NABL accredited test laboratory in respect of such tests for which the lab has been accredited (for Indian make Relays)/ CPRI/ Nationally accredited testing laboratory (for Foreign make Relays). These type test reports should not be older than five years from the date of opening of bid. Bids without Type Test reports will be treated as Non-Responsive.Any other equivalent make of relays shall also be acceptable subject to prior approval of S.E. (TW), JVVNL, Jaipur.

1.11 WIRING :

All wiring shall be of switch board type consisting of copper conductor of 1.5 Sq. mm. for alarm / annunciation / control circuits and 2.5 Sq.mm. for CT and all other Circuits insulated with polyvinyl chloride insulation suitable for 660 Volt service and in accordance with relevant IS:732. Polyvinyl Chloride used shall have excellent resistance against burning, moisture, oil and vermin and shall be finished with clear colour. Rubber insulated wiring shall not be acceptable. Tenderers shall furnish the details of method being adopted by them for Joint/ Connections.

All instruments and Panel wiring shall be of heat resisting and self extinguishing type in compliance with IS. Plastic or porcelain cleats of the limited compression type shall be used for holding wiring runs. All wires shall be suitable for bending to meet the terminal studs at right angles. Metal cases of all apparatus mounted on panels shall be separately earthed by means of copper wire or strips. The following colour scheme of the wiring shall be used as per IS:375.

a) AC three phase circuits :

i) No.1 Phase : Red.

No.2 Phase : Yellow. No.3 Phase : Blue

ii) Neutral Conductor : Black

iii) Connection to Earth : Green

b) D.C. circuits : Grey

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1.12 MIMIC DIAGRAM :

For indoor panels painted colour bands shall be used for the mimic bus. The mimic diagram shall be on eye level. Equipments such as current transformers, voltage transformers etc. shall be represented by suitable symbols. The colour shall be Red Shade 537 of IS-5.

1.13 INDICATING LEDs:

Indicating LEDs shall be provided on the control board to indicate the following:

1. Visual indication of ON and OFF position of each circuit breaker. 2. Trip circuit healthy indication. 3. Auto trip indication for each circuit breaker panel. 4. VT supply indication.

Each lamp body shall be of moulded insulation and shall be able to withstand a high voltage test of appropriate value. All LEDs shall be suitable for 240 V AC supply and shall have low power consumption and shall provide a wide angle of illumination of sufficient intensity for comfortable viewing. A glass of appropriate colour shall be screwed into the front of the LED. The design of LED shall be such as to facilitate replacement of defective LEDs. An engraved label indicating the purpose of the LED shall be provided with each LED.

1.14 TEST TERMINAL BLOCKS :

Two nos. test terminal blocks shall be provided one for testing of relays and other for testing meters. They shall be of switch board, back connected type for front of panel mounting. The test blocks shall provide complete isolation of meters, instruments, etc. and the arrangement shall be such that testing power could be connected at the test block from any external source or may be taken from the instrument transformers. Provision shall be made for short circuiting current transformers. Suitable sealing arrangement shall be provided in test terminal blocks.

1.15 FERRULES :

Ferrules engraved/printed with the same number, letters or symbols as indicated in the connection and wiring diagram shall be provided on the terminal ends of all wires for identification of circuits for inspection and maintenance. Ferrules shall be of strong and flexible insulating material with glossy finish to prevent adhesion. They shall be engraved / printed and clearly marked and shall not be effected by dampness. Ferrule numbering shall be in accordance with IS:375. The same ferrule number shall not be used on wires in different circuits on a panel.

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1.16 SPACE FOR CABLES AND CABLE GLANDS :

Sufficient space for receiving the cables inside the switch board at the bottom of the cubicles and mounting arrangement for the terminal cable glands shall be provided. Cable gland plates should be above the ground level for the ease of working.

1.17 PAINTING & FINISHING:

All interiors and exteriors of switchgear enclosure, breaker mechanism etc shall be finished and painted to produce a neat, fire resistant and durable surface which would prevent rusting and corrosion. Sheet metal component shall be pre-treated using 7 tank phosphating process consisting of de-greasing, acid pickling, de- rusting, phosphating and passivation including repeated rinsing in between. On completion of the passivation of the components,they shall be preheated and then epoxy powder coated or treated with one coat of primer & zinc chromate and finished with two coats of light gray enamel paint of shade 631 of IS 5 and stoved to achieve excellent anti-rusting and scratch resistant properties. The thickness of painting shall be around 60 microns.

1.18 SCHEDULE OF EQUIPMENT :

Item No. 1 (TRANSFORMER TYPE)

36KV/800 Amp. VCB Switchgear panel for indoor installation:

1. 36KV/800A Vacuum Circuit Breaker 1 No. Drawout type with provisions of manual tripping by means of a control switch/push button.

2. Motor Charged Spring operated closing 1 No.

mechanism.

3. Numerical 3 0/C + E/F relay 1 No.

4. Single phase 36 KV current transformers 3 Nos. of ratio 400-200/5-5A suitable for metering and protection. The class of accuracy shall be 0.5 S for metering and 5P15 for protection. Rated burden (output) shall be 30 VA for protection & 15 VA for metering for each secondary core. Instrument security factor for metering core shall not exceed 5.

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5. Flush type switchboard mounting pattern 1 No. Analog voltmeter of class 1.0 or better accuracy suitable for 110 V phase to phase secondary scaled for 0-40 KV.

6. Voltmeter phase selector switch to 1 No.

indicate phase to phase and phase to neutral voltage of all the three phases.

7. Indicating LEDs coloured red, amber and 3 Nos.

blue for PT supply indication.

8. Arrangement for reception of incoming and 2 Nos. outgoing cable connection along with cable termination and sealing kits for 3 C x 400 mm sq. XLPE power cables.

9. Set of three phase air insulated main 1 No.

electrolytic copper bus bars of 800A continuous current rating having maximum current density 1.5 Amp./ Sq. & minimum cross sectional area 720mm Sq. with PVC insulation or sleeves. STC rating 25KA for 3 seconds.

The busses within the cubical shall be of high conductivity electrolyte grade copper. The Bus bar joints shall be silver plated and bolted in such a manner that initial contact pressure around the square headed high tensile bolt will remain substantially undiminished at all temperature upto rated full load temperature. The Bus support and bushings shall be of epoxy resin cast type. All drop off from main bus to VCB and VCB to bushing terminations shall be suitable for current rating of circuit breaker . All the bus bar shall be sleeved with heat shrinkable sleeves of 36 KV voltage level (Insulated for a service voltage of 36 KV) and bus bar shall be shrouded wherever possible. All the bus bar joints shall be shrouded and where shrouding is not possible, it shall be taped with HV self amalgamation tape. All the tap off bus bar connections inside panel and PT jumpers shall be sleeved with HT heat shrinkable sleeves. Special care shall be taken in the design of bus bar system to provide for thermal expansion and to minimize the chances of bus fault. Bimetallic washers shall be provided at the joints of two different metal surfaces.

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The bus supports and bushings shall be non hygroscopic non aging glass reinforced polymer.

10. Mechanical ON/OFF indicator. 1 No.

11. Operating handle for independent manual 1 No. closing mechanism.

12. Red indicating LED for ON indication. 1 No.

13. Green indicating LED for OFF indication. 1 No.

14. Auxiliary switch having minimum of 8 1 No.

contacts 8 normally open and 8 normally closed.

15. Flush mounting pattern analog ammeter of class 1 No.

1.0 accuracy or better for 5 Amps. CT secondary scale 0-200/400 A.

16. Ammeter selector switch to indicate phase 1 No.

current in all three phases and with OFF position.

17. AC HT Tri vector meter 1 No.

18. Auxiliary Relay type VAA 33 or equivalent 2 Nos.

For transformer protection functions.

19. Trip Circuit Supervision Relay 1 No.

20. D.C. Supervision Relay 1 No. 21. Annunciator 16 window 1 No. 22. High Speed Trip Relay 1 No. 23. Semaphore indicators As per requirement 24. Three Position control switch for circuit 1 No.

Breaker & Annunciation window 26. Automatic door CFL with Switch. 1 No.

27. 240V, 80W AC single phase 2 Nos.

anti condensation heaters with thermostat (0-60 eg. C) and switch.

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28. Anti pumping contactor. 1 No.

29. Operation Counter. 1 No.

30. Test terminal blocks for metering and 2 Nos. relays, 3 phase 4 wire.

31. Fault trip yellow LED. 1 No.

32.Ground bus system, size 50x6mm copper 1 No. may be provided and the earthing stud shall

be capable of withstanding rated short circuit current and stud design shall be as per IS- 133427 or IEC -200.

33. Bell for Alarm 1 No.

34. Hooter for Alarm 1 No.

35. 3 Pin Socket with switch 1 No.

36. 2 Pin Socket with switch 1 No.

37. Auto Trip Lamp 1 No. Item No. 2 (FEEDER TYPE)

36KV/800 Amp. VCB Switchgear panel for indoor installation:

1. 36KV/800A Vacuum Circuit Breaker 1 No. drawout type with provisions of manual tripping by means of a control switch/push button.

2. Motor Charged Spring operated closing 1 No. mechanism.

3. Numerical 3 0/C + E/F relay 1 No. 4. Single phase 36 KV current transformers 3 Nos. of ratio 400-200/5-5A suitable for metering and protection. The class of accuracy shall be 0.5 S for metering and 5P15 for protection. Rated burden (output) shall be 30 VA for protection & 15 VA for metering for each secondary core. Instrument security factor for metering core shall not exceed 5.

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5. 33000/110 Volts three single phase voltage 1 Set transformers having 30 VA/phase burden and class of accuracy 0.5. The transformer shall be star-star connected.

6. Flush type switchboard mounting pattern

Analog voltmeter of class 1.0 or better accuracy suitable for 110 V phase to phase secondary scaled for 0-40 KV.

1 No.

7. Voltmeter phase selector switch to indicate phase to phase and phase to neutral voltage of all the three phases.

1 No.

8. Indicating LEDs coloured red, amber and blue for PT supply indication.

3 Nos.

9. Arrangement for reception of incoming and outgoing cable connection along with cable termination and sealing kits for 3 C x 400 mm sq. XLPE power cables.

2 Nos.

10. Set of three phase air insulated main electrolytic copper bus bars of 800A continuous current rating having maximum current density 1.5 Amp./ Sq. & minimum cross sectional area 720mm Sq. with PVC insulation or sleeves. STC rating 25KA for 3 seconds.

1 No.

The busses within the cubical shall be of high

conductivity electrolyte grade copper. The Bus bar

joints shall be silver plated and bolted in such a

manner that initial contact pressure around the square

headed high tensile bolt will remain substantially

undiminished at all temperature upto rated full load

temperature. The Bus support and bushings shall be of

epoxy resin cast type. All drop off from main bus to

VCB and VCB to bushing terminations shall be suitable

for current rating of circuit breaker . All the bus bar

shall be sleeved with heat shrinkable sleeves of 36 KV

voltage level (Insulated for a service voltage of 36 KV)

and bus bar shall be shrouded wherever possible. All

the bus bar joints shall be shrouded and where

shrouding is not possible, it shall be taped with HV self

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amalgamation tape. All the tap off bus bar connections inside panel and PT jumpers shall be sleeved with HT heat shrinkable sleeves. Special care shall be taken in the design of bus bar system to provide for thermal expansion and to minimize the chances of bus fault. Bimetallic washers shall be provided at the joints of two different metal surfaces.


11. Mechanical ON/OFF indicator. 1 No.

12. Operating handle for independent manual 1 No. closing mechanism.

13. Red indicating LED for ON indication. 1 No.

14. Green indicating LED for OFF indication. 1 No.

15. Auxiliary switch having minimum of 8 1 No. contacts 8 normally open and 8 normally closed.

16. Trip Circuit Supervision Relay 1 No. 17. D.C. Supervision Relay 1 No. 18. Annunciator 8 window 1 No. 19. High Speed Trip Relay 1 No. 20. Semaphore indicators As per requirement 21. Three Position control switch for circuit 1 No.

Breaker & Annunciation window

22. Flush mounting pattern Analog ammeter of class 1 No.

1.0 accuracy or better for 5 Amps. CT secondary scale 0-200/400 A.

23. Ammeter selector switch to indicate phase 1 No. current in all three phases and with OFF position.

24. AC HT Tri vector meter 1 No.

25. Automatic door CFL with Switch. 1 No.

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26. 240V, 80W AC single phase 2 Nos. anti condensation heaters with thermostat (0-60 Deg. C) and switch.

27. Anti pumping contactor. 1 No.

28. Operation Counter. 1 No.

29. Test terminal blocks for metering and 2 Nos.

relays, 3 phase 4 wire.

30. Fault trip yellow LED. 1 No.

31.Ground bus system, size 50x6mm copper 1 No. may be provided and the earthing stud shall be capable of withstanding rated short circuit current and stud design shall be as per IS- 133427 or IEC -200.

32. Bell for Alarm

33. Hooter for Alarm

34. 3 Pin Socket with switch

35. 2 Pin Socket with switch

36. Auto Trip Lamp 1.19 All equipments shall be complete

apparatus which may not have been mentioned above but which are usual/necessary for the equipments shall be included for each circuit breaker panel.

1.20 TEMPERATURE RISE :

The maximum temperature rise of various parts of the circuit breakers when tested under rated conditions shall not exceed the specified values at a peak ambient temperature of 50 deg. c. The breakers may be provided with silver plated contacts if necessary to meet the requirement of IS:13118 where higher temperature rise is permitted with silver plating contacts. The quantity of silver facing shall be such that after carrying out one tenth of the total number of operations specified for the mechanical endurance test, there is still continuous layer of silver on the contacts. The temperature rise of CTs and PTs shall also not

1 No.

1 No.

1 No.

1 No.

1 No.

in all respect. All fittings, accessories or

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exceed the permissible values as per relevant Indian Standards when corrected for max. ambient temperature at site.

1.21 NAME/RATING PLATE :

All items of equipment included in this specification shall be provided with rating plates as per relevant standards and in addition with following particulars:-

Name & Address of Supplier : Telephone No. : Fax No. : Date of Dispatch : Date of Expiry of : Warranty Name of Purchaser :

TW/IPDS/ TN No. :

It will be mandatory for the supplier to punch TN No., Sr. No. & Make on two positions of the circuit breaker panel.

1.22 INSPECTION AND TESTING :

1.22.1 Each equipment shall comply with and shall be subjected to all routine and

acceptance tests prescribed in the relevant Indian Standard Specification/IEC. 1.22.2 TEST OF 36KV INDOOR CIRCUIT BREAKER :

i) ROUTINE/ACCEPTANCE TESTS:

The following acceptance and routine tests shall be got conducted in presence of purchaser's representative as per stipulation of the relevant standards, on each unit.

a) One minute power frequency voltage withstand dry test on main circuit. b) Voltage withstand test on control & auxiliary circuits. c) Measurement of insulation resistance of main circuit. d) Mechanical operation test. e) Design and visual checks. f) Any other tests not specified above but covered as per amendment/ latest

edition of relevant IS/IEC.

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ii) Inspection & tests on control gear :

In addition to the above tests at 3.23.2(i) above specified by IEC, the following shall also be performed at manufacturer’s works in the presence of purchaser’s representative after completely assembling the kiosk.

a) Checking wiring of circuits and their contacts. b) Insulation resistance of complete wiring, circuit by circuit with all equipment

mounted on the panels. c) Checking and operational protective schedule and instruments meters. d) Checking of phase faults between R&Y, Y&B and B&R phases. Breaker

should trip under all three conditions.

iii) Temperature Rise test on One No. Breaker in the first offered lot shall also be done in the presence of the purchaser’s representative.

iv) TYPE TESTS CONDUCTED ON MATERIAL AS PER RELEVANT

STANDARDS :

a) Dielectric tests. i) Lightning Impulse Voltage Test. ii) One Minute Power Frequency Test(Wet & Dry).

b) Short time with stand current and peak withstand current test. c) Basic short circuit duties test. d) Single phase short circuit test. e) Mechanical Operation Test as per M-2 class. f) Out of phase making & breaking test. g) Capacitive Current Switching Test.

i) Cable Charging Test. ii) Single Capacitor Bank Current Switching Test.

h) Measurement of insulation resistance of main circuit. i) Temperature rise test. j) IP-5X test (for cubicle/control cabinet). k) Any other type tests not specified above but covered as per amendment /

latest edition of relevant IS/IEC The bidder must furnish type test reports along with bid as per the Qualification

Requirement of the Tender Specification. 1.22.3 The type test reports of Circuit Breakers, Current Transformers, Potential

Transformers, Relays, meters etc. shall be complete in all respect along with oscillographic records, photographs etc. in respect of all type tests as per relevant ISS/IEC.

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The type test certificates should be in respect of specific make and type / rating of the Circuit Breakers/ instruments, transformers etc. intended to be supplied and not in respect of the breakers etc. manufactured by their foreign collaborators if any.

Any bidder having experience for supply of any type of 33 KV & above rating of breakers will be eligible for quoting in this tender.

Necessary data with test reports to show capability of circuit breaker to withstand number of full level short circuit faults be also furnished. Complete literature must be sent with the tender.

1.22.4 Routine & acceptance test as per relevant standard shall be carried out on each

equipment covered by this specification in the presence of purchaser's representative. If so desired by the purchaser all test reports shall be submitted and got approved from the purchaser before dispatch of the equipment. Before commencement of supplies one panel complete with Circuit Breaker, VT etc. will be subjected to temperature rise test in the presence of our Inspecting Officer.

1.22.5 INSPECTION AND TESTS OF CONTROL GEAR :

All the tests (as mentioned at Clause 3.23.2(i)) and Inspection shall be made at the place of manufacturer unless otherwise especially agreed upon by the bidder and purchaser at the time of purchase. The bidder shall afford the inspection officer(s) representing the purchaser all reasonable facilities without charges, to satisfy him that the material is being furnished in accordance with this specification. The purchaser has the right to have the tests carried out at his own cost by an independent agency whenever there is a dispute regarding the quality of supply.

The Inspection may be carried out by the purchaser at any stage of manufacture/ before dispatch as per relevant standard.

Inspection and acceptance of any material under the specification by the purchaser, shall not relieve the bidder of his obligation of furnishing material in accordance with the specification and shall not prevent subsequent rejection if the material is found to be defective. The Bidder shall keep the purchaser informed in advance, about manufacturing programme so that arrangements can be made for inspection.


The Bidder shall give 15 days advance intimation to enable the purchaser to depute his representative for witnessing the acceptance and routine tests.

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1.23 TECHNICAL PARTICULARS : 1.23.1 The tenderers shall furnish the guaranteed technical & other particulars of the

equipments offered 1.23.2 INTER CHANGEABILITY :

All similar materials and removable parts of similar equipments shall be inter changeable with each other.

1.24 OPTIONAL SPARES:

The tenderer shall furnish list of recommended optional spares that will be required for breakers alongwith their total and unit prices.

1.25 TITLE PLATES:

A Title plate bearing the name & purpose of each panel shall be fixed on the top of each indoor panel.

1.26 FAULT / TROUBLE ALARM SCHEME :

The automatic trip of the Circuit Breaker due to operation of protection relays shall be indicated by sounding of a hooter. All non-trip alarms shall be indicated by an alarm bell.

1.27 MAKE AND TYPE OF BOUGHT OUT ITEMS :

1.27.1 The following make of bought out items will be acceptable to department : -----------------------------------------------------------------------------------------------------

S.No. Name of Item Make ----------------------------------------------------------------------------------------------------

1. Indicating Instrument AE/IMP/MECO (Analog type)

2. Indicating Instrument AE/IMP/MECO (Digital type)

3. Control Switch for Circuit ALSTOM/RECOM/SWITRON/ Breaker/Trip Transfer. KAYCEE

4. Selector Switch for SWITRON/KAYCEE/RECOM

Voltmeter/Ammeter

5. Semaphore Indicator ALSTOM/DAV IND./ER

6. Indicating Lamp ALSTOM/TEKNIC/ VAISHNO/DAV

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7. Annaunciator MINILEC/YESHMUN/ INSTALRAM/PROTON/ JVS/PRADEEP/ALAN

8. Push Button TEKNIC/VAISHNO/ESSEN

9. A.C. Hooter/Bell TARGET/INDUSTRIAL HOOTER/ALAN/JVS

10. D.C. Hooter TARGET/INDUSTRIAL HOOTER/ALAN/JVS

11. Heater SOFIA/ELTER/AIREX/KAYCEE

12. Link Type test terminal IMP/CAPITAL block for testing of TVM

13. CFL Tube PHILIPS/CROMPTON/BAJAJ

14. 2 Pin/3 Pin socket with ISI MARK Switch (5/15A)

15. Relays Areva/ABB/Easun Reyrolle/ C&S JVS/SEL/ASHIDA/MEGAWIN 16. HT TVM Secure/L&T/ABB/Elster/Schlumberger

Other makes shall also acceptable if it is of "ISI MARK" or type tested for which tenderers shall furnish attested photo state copies of ISI Certificate/type test report not older than 5 years for the respective make offered with the prior approval of SE(TW) JVVNL, Jaipur.

1.27.2 Make / type of each relay, indicating instruments, integrating instruments,

control switches, selector switches, indicating lamps, semaphore indicators, enunciator scheme, bell, hooter etc. shall be clearly and invariably indicated in the GTP (Guaranteed Technical Particulars), bill of material and unit price list. Only specific make accessories shall be indicated. The word "EQUIVALENT/REPUTED MAKE" will not be given for consideration.

Desirable Features Required for Safety and Smooth functioning of the Circuit

Breaker:

As these breakers are to be installed inside the control room therefore the features related with the operators safety is of the paramount importance.

A) Vacuum Circuit Breaker : i) The VCB shall be totally drawn out type with racking gears with distinct test &

service positions. The contact wipe shall be independent of the manual intervention.

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ii) The movement of VCB shall be duly interlocked so that it can not be racked in to service position in pre closed condition & it is not possible to rack out from service position in pre closed condition. Any attempt to close the VCB into intermediate position shall be blocked by sustained mechanical tripped command overriding on to the mechanism to avoid closure of the contacts of VCB. Any attempt to cause the movement of VCB shall initiate the tripping of a VCB and only thereafter the movement shall be facilitated.

iii) The mechanism shall be trip free type with inherent capability of O-CO operation. iv) The Auxiliary switch shall be 8 N/O + 8 NC contacts. v) keeping in view on unmanned substation and grid complexity, the rated operating

sequence shall be of rapid auto-reclosing duty as O-0.3sec-CO-3min-CO. vi) In view of frequent operations encountered in the distribution system, it is highly

beneficial to Nigam to opt for M2 Class mechanism (suitable for 10000 mechanical endurance operations as per latest IEC-62271-100) as against M1 Class mechanism (suitable for 2000 mechanical endurance operations) which will give long trouble free performance, thus saving huge life cycle costs in terms of maintenance and man power cost.

vii) The Circuit Breaker should be design in such a manner that there should be proper metal compartmentalization of the various circuit breaker parts such as breaker chamber, Bus bar chamber & Cable chamber.

viii) Test and service position limit switches shall be provided. ix) The provision is made to avoid accidental contact & access to the high electrically

stressed area by providing appropriate touch to safe metal screens when the VCB is posed into service position inside the cubical.

x) No separate VCB handling trolley shall be required to insert the VCB inside the panel. The VCB shall be floor rolling type.

xi) The VCB is provided with proper interlock for the secondary isolating plug & socket type contacts so that it is not possible to insert the VCB from the test to service position unless the secondary plug socket is connected & it is not possible to remove the secondary plug socket into intermediate position & in service position. This interlock as per IEC 60298 is an inherent part of the VCB & panel design.

xii) The vacuum interrupter is housed into epoxy pole unit to have better environmental protection & safe operation under the fatal conditions. The bellow for the VI shall be of stainless steel.

xiii) The insulation used shall be non hygroscopic & non deformable type and it is free from any partial discharges when exposed to sustain over voltages.

xiv) The VCB shall be completely type tested as IEC 62271-100/200 or ISS xv) The VCB shall be Tested for E2, M2, C2 test duties.

B) VCB Panel features :

xvi) The panel shall be totally dust and vermin proof & has degree of protection – IP5X.

xvii) The operating instruments like switches etc shall be placed at height less than 1900mm.

xviii) The total height of the panel should not exceed more than 2700mm and width 1200mm.

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xix) The panel is designed totally on air clearances basis with no dependency on the external shrouds & add on insulations.

xx) The panel shall have epoxy spout insulators between the bus bar & VCB chamber to have proper compartmentalization.

xxi) The bus risers shall be epoxy coated and is integral part of the spout bushings. xxii) Entire bus bar compartment is provided with solid insulation scheme to have

less dependency on the inter phase barriers. xxiii) The panel shall have rigid sheet steel construction for better stability and shall

be self standing without the external bracings. The sheet thickness should not less than 3mm.

xxiv) The panel is designed to have gravity operated self resetting type pressure relief flaps to have internal arc fault proof design.

xxv) The panel is having integral foundation frame. xxvi) The CT’s shall be top terminal CT’s and mounted on the panel base frame to

facilitate easy mounting and sevicibilty. xxvii) Adequate cable termination space of around 700mm shall be provided with

facility to terminate 3 cables of 3CX400 sq. mm size. xxviii) Panel is provided with independently operating insulated type non metallic

shutters with pad locking facility. The shutters shall automatically operate with the VCB trolley movement.

xxix) The panel shall be provided with draw out type of 3 No. single phase PT’s. xxx) The multi-core cable entry can be provided optimally from front or rear side of

the panel. Cable entry from LH/RH side through self standing side cable boxes.

Desirable Features for Relay :

i. Numerical 3 over current and Earth fault relay with instant trip. ii. Instantaneous Over-Current Protection with adjustable timer. iii. Breaker Failure detection. iv. In-built CB Trip Circuit Supervision function during pre closing and post closing of

CB. v. DC supervision. vi. Disturbance Recorder. Up 1 sec of actual waveform of current along with logical

and physical status, are captured & saved in the built-in memory with date time stamping, for analyzing fault condition & fault location.

vii. Fully communicable with IEC standard open protocol. viii. Separate Communication Port for SCADA (RS485) as well as Local testing

(RS232C) ix. Very low burden on CT (less than 0.5VA) x. Continuous monitoring of module’s internal hardware and alarm generation in

case of failure of any critical components. xi. Facility to synchronized Relay time from SCADA xii. 5 Digital Output contacts for local alarm as well as tele-signalling

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TECHNICAL SPECIFICATION FOR 36 KV OUTDOOR VACUUM CIRCUIT BREAKERS

1. SCOPE : This specification is intended to cover the design, manufacture, assembly, testing at manufacturer's works, supply, delivery, installation & commissioning (As per Section-III Part-B) of 36 KV Outdoor Vacuum Circuit Breakers Complete with all materials and accessories for efficient and trouble free operation.

It is not the intent to specify completely herein all details of the design and construction

of equipments. However, the equipment shall conform in all respects to high standards of engineering, design and workmanship and shall be capable of performing in continuous commercial operation upto the Bidder's guarantee in a manner acceptable to the Purchaser, who will interpret the meanings of drawings and specifications and shall have the power to reject any work or material which in his judgment is not in accordance therewith. The offered equipment shall be complete with all components necessary for its effective and trouble free operation along with associated equipments, interlocks, protection schemes etc. Such components shall be deemed to be within the scope of supply, irrespective of whether those are specifically brought out in this specification and/or the commercial order or not.

2.0 STANDARDS :

The circuit breaker shall conform to the latest revisions with amendments

available at the time of testing of relevant standards, rules and codes, some of which are listed herein for ready reference:-.

IS:13118/IS-3427/ IS:10118 (Part-III) – 1982/ IS:2165-1977/ IS:3716-1976/ IEC- 62271-100/ IEC-62271- 200 (with latest amendments)

Circuit Breaker/ metal enclosed Switchgearand control gear.

IS: 3156 Voltage transformers. IS: 2705 Current transformers. IS: 3231 Electrical Relays for power system. IS:1248 Meters and Instruments IS:14697-1999 Specification for AC static transformer operated watt

hour and VAR hour meters class 0.2 S & 0.5 S. IEC-62053-22-2003 IEC-62052-11-2003

Specification for AC Static Watt hour Meters, class 0.2 S & 0.5 S.

CBIP Technical Report No.88 revised July, 1996 read with amendment issued (April,99, September,99 and also any other amendment thereafter).

Specification for AC Static Electrical Energy Meter.

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3.0 Equipment meeting with the requirements of any other authoritative standards, which ensure equal or better quality than the standard mentioned above shall also be acceptable. If the equipment offered by the Bidder conforms to any other standard adopted and the specific standards shall be clearly brought out in relevant schedule. Four copies of such standards with authentic English Translations, shall be furnished alongwith the offer.

4. PRINCIPAL PARAMETERS OF CIRCUIT BREAKERS :

4.1 TYPE AND RATING 36 KV

4.1.1 Type Vacuum Circuit Breaker

4.1.2 Service Outdoor

4.1.3 Pole 3

4.1.4 Rated voltage 33/36 KV (nominal/max.)

4.1.5 Rated frequecy 50 Hz

4.1.6 System Neutral Effectively earthing grounded.

4.1.7 INSULTATION LEVEL

4.1.7.1 Impulse withstand voltage 170 KVp

4.1.7.2 ute power 70 KV rms

frequency withstand voltage.

4.1.8 Rated Current 4.1.8.1 Continuous at 50 C. 1250 A

4.1.8.2 ort time current 25 kA

for 3 Sec.

4.1.9 Rated Breaking Capacity

4.1.9.1 terical 25 KA

4.1.9.2 symmeterical As per relevant standard

4.1.10 Rated making capacity 2.5 x 25 KA

4.1.11 Rated short time with 25 KA stand current for 3 secs.

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4.1.12 a) Total break time 3 cycles(Max.) b) Total closing time 4 cycles (Max.)

4.1.13 Creepage distance 900 mm or more

4.1.14 Mounting. Steel Pedestal.

4.1.15 Operating duty

For gang operation O-0.3Sec.-CO-3min-CO 4.1.16 Operating Mechanism Motor operated

Spring charged closing mechanism or magnetic actuator.

4.1.17 Auxiliary voltage. 110 VDC

4.1.17.1 pring charging Motor 230V/415V AC

4.1.17.2 Heater/Lamp/Socket. 230V AC

4.1.18 Terminal Connector

4.1.18.1 Type Bimetallic/Alluminium Alloy Type clamp

suitable for both horizontal /vertical take off

4.1.18.2 table for 10% Panther and

ACSR Conductor 90% Dog Conductor 4.2 System details

4.2.1 H.V. System

Voltage (Nominal/Max.) 33 KV /36 KV

Phases 3

System Neutral Effectively earthed.

Fault level 25 KA rms Symmetrical 4.2.2 Auxiliary power Supply

4.2.2.1 A.C. Supply 1. 415 volts 3 ph 4 W 50 Hz

2. 230V 1 Ph 2 W 50 Hz 4.2.2.2 D.C.Supply 110 V 2 wire.

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4.3 Supply point.

4.3.1 Auxiliary power supplies listed above will be made available to each circuit breaker as below :

AC supply. Single feeder. DC supply. Single feeder.

4.3.2 Isolating switch fuse unit shall be provided at the circuit breaker for each incoming

supply. For DC supply double pole throw switch shall be provided. 5. GENERAL TECHNICAL REQUIREMENTS :

5.1 DESIGN CRITERIA :

The 36 KV Outdoor VCBs shall be conforming to M-2 Class. The equipment will be used in high voltage system having characteristics as listed in the specification. The equipment will be installed outdoor in a hot, humid and tropical atmosphere. All equipment, accessories and wiring shall have tropical protection, involving special treatment of metal and insulation against fungus, insects and corrosion.

The maximum temperature in any part of the equipment at specified rating shall

not exceed the permissible limits as stipulated in the relevant standards even at an ambient temperature of 50 Deg.C.

The equipment shall be capable of withstanding the dynamic and thermal

stresses of listed short circuit current without any damage or deterioration.


5.2 SPECIFIC REQUIREMENTS :

5.2.1 The circuit breaker shall be for outdoor installation, three pole vacuum type,

having internal isolation without any sequential interlock.

The duty of the circuit breaker shall involve satisfactory interruption of short circuit currents as listed in the specification.

5.2.2 CONSTRUCTIONAL FEATURE :

Each circuit breaker shall comprise three identical poles, complete with a gang operated mechanism for specified duty.

All these poles of circuit breaker shall be linked together electrically and mechanically for specified duty.

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The circuit breaker units shall be complete with operating mechanism and other accessories and materials to ensure complete assembly and proper functioning. The following features should be ensured:-

a) Hinges of door shall be concealed type to avoid rusting and obstructive

opening of the door. b) The quality of welding shall be good and there should not be any lumps and

splatters on the panel”. c) All the connecting bus bar and current carrying parts shall be made of

copper. d) All the gasket shall be of chemically treated neoprene. e) Hole & Pin locking (Check nut) arrangement should also be provided while

fixing the vacuum interrupter at bottom side. f) The vacuum interrupter should be housed in epoxy pole unit and make of

Vacuum Interrupter is required to be from BEL, CGL, SIEMENS, ABB or ALSTOM/AREVA/MEGAWIN.

5.2.3 BUS BAR, MAIN CONTACTS AND ARC QUENCHING CHAMBER :


The main contacts shall have adequate area and contact pressure for carrying rated continuous and short time current without excessive heating liable to cause pitting and welding.

The tips of the arcing and main contacts shall be heavily silver plated (Min. 40 microns) or made of copper chromium alloy.

The contacts shall be adjustable to allow for wear, shall be easily replaceable and shall have minimum movable parts and adjustments.

The arc quenching device shall be of robust construction and shall not require any critical, adjustment. The devices shall be easily accessible and removable for access to the breaker contacts.

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5.2.4 AUXILIARY CONTACTS :

Each breaker shall be provided with eight normally open & eight normally closed electrically separate auxiliary contacts. These shall be in addition to those required for its own operation and indication.

The auxiliary contacts shall be convertible type so that normally open contacts can be converted into normally close contact and vice versa at site.

The auxiliary contacts shall be rated 10A at 240V AC and 4A at 110 V DC.

5.2.5 INTERLOCK :

All electrical and mechanical interlocks which are necessary for safe and satisfactory operation of the circuit breaker shall be furnished.

5.2.6 INSULATOR :

Insulator shall be wet process porcelain, brown glazed and free from all blemishes. Metal parts and hardware shall be hot dip galvanised.

Insulator shall have adequate mechanical strength and rigidity to withstand the duty involved.

When operated at maximum system voltage, there shall be no electrical discharge. Shielding rings, if necessary, shall be provided.

Insulation shall be coordinated with basic impulse level of the system. The creepage distance shall correspond to heavily polluted atmosphere.

The bushing shall not be subjected to direct point loading. They shall be provided with neck around clamps for evenly distributed pressure.

The bushing shall be mounted using suitable clamps and gasket arrangement to provide required degree of protection.

The bushing assembly shall be provided with lock nut and check nut which will be non-magnetic and non-corrosive.

The provision shall be kept on roof bushing assembly to adopt arcing horn.

The lifting arrangement shall not cause any effective loss of creepage distance/ phase to earth clearances as specified in the ISS/IEC.

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5.2.7 OPERATING MECHANISM :

Operating mechanism shall be spring operated with anti pumping and trip free features, complete with shunt trip coils. All three breaker poles shall operate simultaneously. Circuit breakers shall have provision so as to be suitable for three phase auto reclosing. In case of spring closing mechanism, no main spring of the mechanism shall be plated, powder coated or given any other treatment, so that spring property is not lost. The motor shall be universal type suitable for 220/240V. Spring Charge Indication Lamp shall be provided.

The mechanism shall be designed for electrical control from remote as well as local position. In addition to this, local manual trip button shall be provided. Operation counter and mechanical ON-OFF indicator shall be provided.

5.2.8 CONTROL CUBICLE :

A common control cubicle shall be furnished to house electricals, controls, monitoring devices and all other accessories except those which must be located on individual poles. The cubicle shall be IP-55 of gasketed weatherproof construction, fabricated from sheet steel minimum 3 mm thick.

The cubicle shall have front access door with lock and keys, and removable gland plate at the bottom for owner's cable entry. Thermostat controlled space heater, internal illumination lamp 3 pin 5 A socket with individual ON-OFF switches shall be provided in the cubicle.

For local operation following shall be provided :

a) Local/Remote selector switch. b) Trip normal close control switches with pistol grip handle.

All electrical, mechanical connections between the control cubicle and individual poles shall be furnished.

5.2.9 WIRING

Wiring shall be complete in all respects to ensure proper functioning of the control, protection, monitoring and interlocking schemes.

Wiring shall be done with flexible 650V grade, PVC insulated, switch board wires with 2.5 sq.mm stranded copper conductor. Wiring between individual poles and control cubicle shall be routed through G.I. conduits.

Each wire shall be identified at both ends with permanent markers bearing wire numbers as per wiring diagram.

Wire termination shall be done with crimping type connectors with insulating sleeves. Wires shall not be spliced between terminals.

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All spare contacts of relays, push bottons, auxiliary switches etc. shall be wired upto terminal blocks in the control cubicle.

5.2.10 TERMINAL BLOCKS :

Terminal blocks shall be 650 V grade, box clamp type ELMEX 10 sq.mm or approved equal. Not more than two wires shall be connected to any terminal. Spare terminals equal in number to 20% of active terminals shall be furnished.

Terminal blocks shall be located to allow easy access. Wiring shall be so arranged that individual wires of an external cable can be connected to consecutive terminals.

5.2.11 TYPE OF MOUNTING :

The circuit breaker shall be suitable for mounting on fabricated galvanised steel pedestal which shall be supplied along with the breakers. CT mounting bracket will also be supplied along with the breaker and shall be galvanised.

5.2.12 TERMINAL CONNECTORS :

1250 Amp. current rating terminal connectors of the circuit breakers suitable for connecting to ACSR Panther and Dog Conductor shall be supplied along with the breakers. Suitable earth connectors for earthing connections shall also be supplied with the circuit breakers. The terminal connectors shall conform to relevant standard IS-5561.

5.3 FITTING AND ACCESSORIES :

Each circuit breaker shall be furnished complete with fittings and accessories as listed below :

5.3.1 Clamp type bimetallic/Alluminium Alloy terminal connectors suitable for ACSR

Panther and Dog Conductor suitable both for horizontal & vertical take off. 5.3.2 Two ground pads suitable for termination of 50 x 6 mm flats.

5.3.3 Complete mounting steel pedestal along with CT mounting bracket.

5.3.4 Operating mechanism, double tripping coils and closing coil.

5.3.5 Auxiliary contacts and relays.

5.3.6 Local/remote selector switch, trip normal close control pistol control switch.

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5.3.7 Manual tripping devices with protective flap for VCB's only mechanical ON-OFF indicator.

5.3.8 Operation counter.

5.3.9 Weather proof outdoor type control cubicle and pole boxes. Set of switch fuse

units for AC and DC supply. 5.3.10 pace heater with thermostat and ON-OFF switch.

5.3.11 Cubicle illumination lamps with ON-OFF switch.

5.3.12 Pin 5A socket with ON-OFF switch.

5.3.13 Terminal blocks and internal wiring - lot as required.

5.3.14 Set of prefabricated pipe, fittings, clamps, hardware, interconnecting wires/cables

etc. for connection between control cubicle and pole boxes as may be required to complete.

5.3.15 Interconnecting wires, GI conduits and accessories for connection between

control cubicle and pole boxes. 5.3.16 Other standard accessories which are not specifically mentioned but are

required to be supplied with breakers of similar type and rating for efficient and trouble free operation.

5.4 PAINTING & FINISHING

All interiors and exteriors of switchgear enclosure, breaker mechanism etc shall be finished and painted to produce a neat, fire resistant and durable surface which would prevent rusting and corrosion. Sheet metal component shall be pre-treated using 7 tank phosphating process consisting of de-greasing, acid pickling, de- rusting, phosphating and passivation including repeated rinsing in between. On completion of the passivation of the components, they shall be preheated and then epoxy power coated or treated with one coat of primer & zinc chromate and finished with two coats of light gray enamel paint of shade 631 of IS 5 and stoved to achieve excellent anti-rusting and scratch resistant properties. The thickness of painting shall be around 60 microns.

6.0 TESTS:

6.1 TEST BEFORE DESPATCH : The 36 KV circuit breakers and accessories shall be

subjected to the following tests as per relevant IS/IECbefore dispatchat manufacture's works ,.

A) ROUTINE TESTS ON EACH UNIT AS PER RELEVANT STANDARDS :

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(i) One minute power frequency voltage withstand dry test on main circuit.

(ii) Voltage withstand test on control & auxiliary circuits.

(iii) Measurement of the resistance of main circuit. (iv) Mechanical operating test as per M-2 class. (v) Design and visual checks.

B) TYPE TESTS CONDUCTED ON ONE UNIT OF EACH RATING

6.2 TYPE TESTS :

The bidder must furnish type test reports along with bid as per the qualification requirement of the Tender Specification.

6.3 TEST ON BOUGHT OUT ITEMS :

Tests are not required to be performed on bought out equipments/items like motor, terminal connector, CTs, PTs, Relays, Meters etc. at the works of manufacturer. Furnishing Test Certificate of these items from the original equipment manufacturers shall be deemed to be satisfactory evidence. Inspection of the tests at Sub-contractors works will be arranged by the supplier whenever required.

6.4 ROUTINE/ACCEPTANCE TESTS :

(i) The following acceptance and routine tests shall be got conducted in presence of purchaser's representative as per stipulation of the relevant standards, on each unit.

a) One minute power frequency voltage withstand dry test on main circuit. b) Voltage withstand test on control & auxiliary circuits. c) Measurement of the resistance of main circuit. d) Mechanical operating test as per M-2 class. e) Design and visual checks f) Any other test not specified above but covered as per amendment/latest edition

of relevant IS/IEC. 6.5 TOLERANCE ON TEST RESULTS :

As per relevant standards/specification.

6.6 TEST AT SITE : The purchaser reserves the right to conduct all tests on 36 KV circuit breakers after arrival at site and the contractor shall guarantee test certificate figures under actual service conditions.

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7.0 INSPECTION :


The Inspection may be carried out by the purchaser at any stage of manufacture/ before despatch as per relevant standard.

Inspection and acceptance of any material under the specification by the purchaser, shall not relieve the bidder of his obligation of supplying material in accordance with the specification and shall not prevent subsequent rejection if the material is found to be defective. The Bidder shall keep the purchaser informed in advance, about manufacturing programme so that arrangements can be made for inspection.


The Bidder shall give 15 days advance intimation to enable the purchaser to depute his representative for witnessing the acceptance and routine tests.

8.0 DOCUMENTATION :

8.1 All drawings shall conform to International Standards Organization (ISO) À',

series of drawing sheet / specification, Standards specification IEC-56/IS-13118 & relevant standards. All drawings shall be in ink and suitable for micro filming. All dimensions and data shall be in S.I Units.

8.2 List of drawings and documents :

The bidder shall furnish four sets of following drawings along with his offer.

a) General outline and assembly drawings of the equipment.

b) Graphs showing the performance of equipments in regard to magnetization characteristics.

c) Sectional views showing -

i) General Constructional features. ii) the materials/ gaskets /sealings used.

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iii) the insulation, the winding arrangements, method of connection of the primary/secondary winding to the primary/ secondary terminals etc.

iv) porcelain used and its dimensions along with the mechanical and electrical characteristics.

d) arrangement of terminal's and details of connection studs provided.

e) Name / Rating Plate

f) Schematic Wiring drawing with write up.

g) Type test reports in case the equipment has already been type tested.

h) Test reports, literature, pamphlets of the bought out items, and raw material.

All items of equipment included in this specification shall be provided with rating plates as per relevant standards and in addition with following particulars :

i) Name & Address of Supplier ii) Telephone No. iii) Fax No. iv) Date of Despatch v) Date of Expiry of Warranty vi) Name of Purchaser vii) TW/IPDS/TN No.

8.3 The manufacturing of the equipments shall be strictly in accordance with the


8.4 Approval of drawings/work by purchaser shall not relieve the supplier of his

responsibility and liability for ensuring correctness and correct interpretation of the drawings for meeting the requirement of the latest revision of applicable standards, rules and codes of practices. The equipment shall conform in all respects to high standards of engineering, design, workmanship and latest revisions of relevant standards at the time of ordering and purchaser shall have the power to reject any work or materials which, in his judgement is not in full accordance therewith.

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TECHNICAL SPECIFICATION FOR SUPPLY OF ISI MARKED PVC INSULATED MULTI-CORE UN-ARMOURED NON-FRLS CONTROL CABLES

1.0 SCOPE:

The specification covers design, manufacturing, testing at the manufacturer’s

works, inspection, packing and delivery to the site of 1100V grade multi core, each core containing appropriate numbers of strands of annealed bare.

2.0 PVC INSULATED UN-ARMOUREDNON-FRLS CONTROL CABLES:

The cables are required at various 33 KV Grid Sub-Stations for the control and supervision of outdoor / indoor switchgears and power transformers including instrumentation metering, indication and alarm on the control panels and electrical interlocking between high voltage equipments. With a view to achieve these multifarious requirements, the cables will be laid between individual outdoor equipments and from there to control relay and other allied panels located indoor. The reliability and long life of the control cables is of paramount importance. All the control cables offered against the specification should be suitable for climatic conditions prevailing at site, as indicated in Clause-3.

3.0 STANDARDS FOR UN-ARMOUREDNON-FRLS CONTROL CABLES:

1100V Grade multi core, each core containing seven strands of annealed bare Copper conductor, PVC (Type-A) insulated and PVC sheathed (Type-ST-1), Un-Armoured NON-FRLS Control cables, shall conform in all respects to the following relevant ISS with latest editions and amendments.

Sr. No. Standard Ref. No. Title

1. IS-1554/(Pt.-I)/1988 with latest amendment up to date.

PVC insulated (Heavy duty) Electric Cables for working voltage up to and including 1100 Volts.

2. IS-8130/1984 with latest amendment up to date.

Conductors for insulated Electric Cables and flexible cords.

3. IS-5831/1984 with latest amendment up to date.

PVC Insulation and sheath of Electric Cables.

4. IS-3961/(Pt.-II)/1967 with latest amendment up to date

Current ratings for cables:

PVC insulated & PVC Sheathed heavy- duty cables.

5. IS-10418with latest amendment up to date.

Drums for Electric Cables.

6. IS-10810 with latest amendment up to date.

Methods of tests for cables.

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4.0 GENERAL DESIGN CRITERIA:

The Cables shall normally be laid in masonry / RCC trenches whether inside or

outside the control room building in groups in tier formation or otherwise, but at some places the cables may be laid direct in ground or in air. The cable may even be laid in vertical formation and in steep gradients at some locations. The cables shall be physically strong to withstand rough installation hazards and thermal / electrical / physical stresses during operation under specified climatic conditions

5.0 CONSTRUCTIONAL FEATURES:

1100 Volts grade, multi-core, Un-Armoured NON-FRLS, PVC Type-A insulated suitable for maximum rated conductor temp. of 70° Celsius , seven strands Annealed bare copper conductor, PVC sheathed (Type-ST-1), control cables shall conform to the requirements imposed in IS: 1554 (Part- I)/1988 and its latest amendments up to date. The cable shall be suitable for use where combination of ambient temperature and temperature rise due to load results in conductor temperature not exceeding 70°Celsius under normal operation and 160°Celsius under short circuit conditions.

All the control cables shall bear ISI certification marks as per IS: 1554 (Part-I)/1988 with latest amendment up to date. The cables shall have PVC fillers to provide circular cross-section before the inner sheath is applied. The fillers should be suitable for operating temperature of the cable compatible with the insulating material.

5.1 CONDUCTOR:

The conductor shall be stranded (7 wires per core) annealed, non-compacted, un-tinned high conductivity electrolytic copper conforming to class-II of IS: 8130 /1964 & IS: 613 /1964 with latest amendment up to date.

5.2 INSULATION:

The insulation shall be Polyvinyl Chloride compound (PVC) conforming to

requirement of Type-A compound of IS: 5831/1984with latest amendment up to date. The insulation shall be applied by pressure extrusion method. The insulation shall be applied in such way that it fits closely on conductor and it shall be possible to remove it without damage to the conductor. The thickness and tolerance on thickness of insulation shall be as per clause 9.2 & 9.3 of IS: 1554 (Part-I)/1988with latest amendment up to date.

5.3 INNER SHEATH: The inner sheath shall be of non-Hygroscopic, Polyvinyl Chloride compound (PVC)

conforming to requirements of IS: 5831/1984 with latest amendment up to date for type ST-1.The inner sheath shall be softer than the insulation. The inner sheath shall be applied by extrusion method& it shall be so applied that it fits closely on laid up cores and it shall be possible to remove it without damage to the insulation. The thickness and tolerance on thickness of inner sheath shall be as per clause 12.3 of IS: 1554 (Part-I)/1988 with latest amendment up to date. The inner sheath shall be of colour of black.

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5.4 FILLERS:

The fillers shall be of non-Hygroscopic, Polyvinyl Chloride compound (PVC) conforming to requirements of IS: 5831/1984 with latest amendment up to date. The material of fillers shall be softer than the insulation. It shall be ensured that the shape is as circular as possible. The fillers should be suitable for operating temperature of the cable compatible with the insulating material.

5.5 OUTER SHEATH:

The outer sheath shall be of Polyvinyl Chloride compound (PVC) conforming to requirements of IS: 5831/1984 with latest amendment up to date for type ST-1.The outer sheath shall be applied by extrusion method. The thickness and tolerance on thickness of outer sheath shall be as per clause 14.4of IS: 1554 (Part-I)/1988with latest amendment up to date. The outer sheath shall be embossed at the interval of one meter length as per clause no. 9.0 of this specification.

6.0 COLOUR SCHEME FOR INDENTIFICATION OF CORES:

The Colour of core insulation upto 5 Cores shall be as per clause 10.1 of IS-1554 (Part- I) 1988 and for 6Cores& above, cores shall be identified by the Colour as per clause 10.1(f) of IS-1554 ( Part-I) 1988 & its latest amendment up to date with Grey Colour base and also individual cores of cable containing two or more cores shall be identified by different colouring of PVC insulation in accordance with clause 10.0 of IS: 1554 (Part- I)/1988 with latest amendment up to date. However, the PVC sheath may be black or grey. The colour coatings employed in the formation of the cables for individual cores and sheath shall be indicated in the tender.

7.0 LAYING UP OF CORES: The cores shall be laid up together with the suitable right hand lay. The interstices shall

be filled with non-hygroscopic, PVC material.

8.0 STANDARD LENGTH:

The control cables shall be supplied in standard length of 1000 meters ± 5% for

cables sizes 4CX2.5 Sq. mm. & 2CX2.5 Sq. mm. and shall be supplied in standard length of 500 meters ± 5% for cables sizes 12CX2.5 Sq. mm and 4CX4 Sq.mm. The quantities of the non-standard drum length to be supplied shall not exceed 5% of the ordered qty. but none of which shall be less than 250 meters. The ordered quantity to be supplied shall be subjected to tolerance of ± 2% in each size.

9.0 EMBOSSING:

To enable identification of control cable the word JVVNL, manufacturer’s name or

mark, TN No. & Year of manufacture, Type-PVC, Electric voltage grade and cable size

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shall be embossed on the outer sheath of cable at the interval of one meter length for which no extra charges shall be paid. The cable should be ISI marked & same should be embossed on the outer sheath of every meter of length of cable.

10.0 MARKING: 10.1 The cables shall be wound on non-returnable wooden drums conforming to

IS:10418/1982 of suitable size and packed. The ends of the cable shall be sealed by means of non-hygroscopic sealing material. Only one cable length shall be supplied on a drum. The shaft diameter of Drum shall be as per relevant ISS but not less than 50 mm. The cable can also be supplied on M-Steel Drums as per relevant ISS as applicable.

10.2 The cable shall carry the following information stenciled / painted on the drum :

i) Reference to this Indian Standard, for example, Ref IS:1554 (Part-1) ii) Manufactuer's name, Brand name or trade mark.

iii) Type of cable and voltage grade. iv) Number of Cores. v) Nominal Cross-sectional area of the conductor. vi) Cable Code.

vii) Length of cable on the drum. viii) Approximate gross weight.

ix) Year of manufacture. x) BIS Certification mark. xi) Name of the Consignee and full destination.

xii) TW/IPDS/TN No. xiii) The word suitable for outdoor use & low temperature Conditions.

11 CURRENT RATINGS:

The current ratings of the control cables shall correspond to the values

recommended as per IS: 3961 (Part- II)/1967 and its latest amendments up to date. 12.1 LATENT DEFECTS ERRORS & OMISSIONS:

12.2 Any cable or part thereof that may develop defects during performance guarantee period shall be promptly replaced by the supplier free of charge.

12.3 If the operation of the cable after installation during guarantee period proves to be unsatisfactory, the purchaser shall have the right to operate the bank guarantee(s) until defective articles are taken out of service, without loss of injury to the purchaser & correction of latent defects, errors & omissions.

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13. TESTS & INSPECTION:

13.1 TYPE TEST:

i) The material offered, shall be fully type tested as per relevant standard of specification of IS:1554 (Part.1/1988) amended up to date

ii) The bidder must also clearly indicate various testing facilities available at their works

for testing the material as per relevant standards. In case of otherwise particulars of the place where such testing in proposed to be conducted during the course of inspection shall be indicated with the offer.

iii) However, the purchaser reserves the right to demand repetition of same or all the

type tests in presence of purchaser’s representative. iv) The bidding firms (manufacturers) must have valid BIS license for the offered cable.

The bidder shall furnish the details of BIS License granted to them. The details of type test are as under:

a) Test on Conductor

1. Annealing test (if applicable) 2. Conductor resistance test.

b) Tests for thickness of insulation and sheath. c) Physical tests for insulation and outer sheath.

1. Tensile strength and elongation at break. 2. Aging in air oven. 3. Shrinkage test. 4. Hot deformation. 5. Loss of mass in air oven. 6. Heat shock test. 7. Thermal stability.

d) Insulation resistance test. e) High voltage test (Water immersion test). f) High voltage test at room temperature. g) Flammability tests: The purchaser reserves the right to get the material tested in any recognized test

house and reject the material if not found as per specification.

13.2 ROUTINE TESTS: All routine tests as stipulated in the relevant IS-1554 (Part-I)/1988 with its latest amendments shall be carried out by the supplier on each lot offered for inspection.

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13.3 ACCEPTANCE TESTS:

All the acceptance tests as mentioned in relevant IS-1554 (Part-I)/1988 & its latest amendments up to date shall be carried out on samples from a lot for the purpose of acceptance test in presence of purchaser’s representative.

13.4 INSPECTION:

i) The inspection may be carried out by the purchaser at any stage of manufacturer. Acceptance of any equipment / material under this specification by the purchaser shall not relieve the supplier of his obligation of furnishing equipment in accordance with the specification and shall not prevent subsequent rejection if the equipment/material is found to be defective.

ii) The acceptance tests as per IS-1554 (Part-I)/1988 shall also be conducted by the

manufacturer before dispatch in the presence of our Representative /Inspecting Officer. The mass of Copper, PVC & Filler in sample coils shall also be verified by the Inspecting Officer(s).

Cold bend/ cold impact test (IS:5831/1984) shall constitute the optional tests and shall be conducted on first lot and any from other lot of the offered cables of each size as per Clause No.15.4 of IS-1554 (Part-I)/1988.

iii) The purchaser reserves the right to insist or witnessing the acceptance / routine

tests of the bought out items.

iv) The bidder shall furnish Packing list mentioning serial Nos. of Drums, length in each drum, gross weight of drum without lagging alongwith inspection offer duly signed by the authorized representative of the firm. The purchaser reserves the rights to insist for witnessing the acceptance / routine tests of the bought out items.

v) At least 5% of total numbers of drums subject to minimum of 2 in any lot put up

for inspection shall be selected at random to ascertain the length/ workmanship of cable by the following method :

“At the works of the manufacturer, the cable shall be transferred from one drum to another for checking any manufacturing defects in the cable drums selected for conducting acceptance tests, at the same time measuring its length with the help of the graduated pulley & cyclometer. The difference in the average length thus obtained from the declared length by the supplier in the packing list shall be applied to all the drums if the cable is found short during checking the sample lot(s)”.

vi) The supplier shall present the latest Calibration Certificate(s) of testing

instruments / equipments to be used for the testing of the material covered in the Purchase Order to the authorized inspecting officer / inspecting agency of the purchaser. The testing instruments / meters / apparatus etc. should be got

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calibrated by the supplier from time to time from Govt. Laboratory or any independent test laboratory / house having valid accreditation from National Accreditation Board for Testing and Calibrating Laboratories for the testing equipments / original manufacturer having trace ability to NABL / NPL or equivalent.

The calibration certificate(s) should not in any case be older than one year at the time of presenting the same to the inspecting officer / inspecting agency of the purchaser. The testing instruments / equipments should be duly sealed by the Calibrating Agency and mention thereof shall be indicated in the calibration certificate(s).

13.5 VERIFICATION OF LENGTH:

The supplier / manufacturer shall provide all adequate facilities at his works for inspection of at least two numbers of cable drums or five percent of the cable drums offered for inspection, whichever is higher, selected at random by the authorized representative of the purchaser for checking / verification of cable length / manufacturing defects by transferring the cable from one drum to the another empty drum and at the same time measuring the length of the cable so transferred by means of a meter. The difference in the average length thus obtained from the declared length by the supplier in the packing list shall be applied to all the drums if the cable is found short during checking the sample lot(s).

13.6 CALIBRATION CERTIFICATE:

The successful tenderer shall have to furnish the latest calibration certificates of the testing instruments / equipments used for the testing of material / equipment offered to inspecting officer(s) at the time of inspection of material / equipment. The testing instrument/equipment shall be got calibrated by the manufacturer of testing instrument / equipment or from any Govt. / Govt. recognized / NABL accredited testing laboratory. The calibration certificate should not be older than one year at the time of presenting the same to the Inspecting Officer.

13.7 GENERAL:

All aforesaid tests shall be made prior to dispatch in the presence of representative of the purchaser. In case of inspection waiver, test results must be sent in quadruplicate for approval. No material shall be dispatched without prior inspection or approval of test certificate unless otherwise agreed to in writing by the purchaser.

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TECHNICAL SPECIFICATION AND SCHEDULE OF REQUIREMENT FOR SUPPLY OF

11 KV CROSS-LINKED POLYETHYLENE (XLPE) INSULATED POWER CABLES

1. SCOPE:

This section provides for manufacture, testing before dispatch and supply of ISI Marked 11 KV Aluminium conductor Screened, Cross linked Polyethylene (XLPE) Insulated Armoured Shielded PVC Sheathed cable of rated voltage 11 KV (earthed system) conforming to IS:7098 (Part-II/1985) with latest amendment.

The 11 KV Aluminium Conductor, Screened CROSS-LINKED POLYETHEYLENE

(XLPE) INSULATED Armoured Shielded PVC Sheathed Power cable shall be ISI marked.The bidder should be a manufacturer of tendered item. The offers from Sole Selling Agents / Authorized Dealers shall not be entertained.

The bidder must possess valid ISI License for the bid item. The technical bid of

the bidder shall be considered for opening in the absence of non-furnishing of above required ISI License along with the bid. However, price bid of the responsive bidder shall only be opened if bidder furnishes above required ISI License upto official working hours of 3CX185ne working day prior to the scheduled / notified date of opening of price bids, failing which price bid of the bidder shall not be opened. The firm must possess ISO-9001 or above certification.

2. STANDARDS:

Unless otherwise stipulated in this specification the following standards with latest

amendments shall be applicable. i) IS:7098(Part-II) : Cross linked Polyethylene

Insulated PVC sheathed cable for voltage from 3.3 KV upto & Including 33 KV.

ii) IS:8130 : Conductors for insulated Cables.

iii) S:5831 : PVC insulation and sheath of

Electric cables.

iv) IS:3975 : Mild steel wires, strips and tapes for armouring cables.

v) IS:10810 : Methods of test for cables.

iv) IS:10418 : Drums for Electric Cables

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3. GENERAL REQUIREMENT:

3.1 The 11 KV power cable shall be ISI Marked Aluminium conductor screened cross linked polyethylene insulated armoured shielded and over all PVC sheathed. The 11 KV XLPE Cable shall conform to IS: 7098 (Part-II)/1985 with latest amendments shall bear ISI Certification mark. The cable shall be capable of withstanding the normal stresses associated with transportation, erection, reeling and unreeling operations without getting deformed.

3.2 The 11 KV XLPE Cable shall be suitable for the following conditions of laying:

i) Laid directly in ground.

ii) Installed outdoor in free air in vertical position. iii) Drawn into underground ducts.

3.3 The 11 KV XLPE Power Cable shall be suitable for use where combination

of ambient temperature and temperature rise due to load results in conductor temperature not exceeding 90 degree C. under normal operation and 250 degree C under short circuit conditions.

3.4 The cable shall be used on 11 KV earthed system. The cables shall be

suitable for continuous operation at a power frequency voltage 10% higher than rated voltage.

4.1 MATERIAL:

4.2 CONDUCTOR: The conductor shall be composed of aluminium wires

complying with the requirement of Class-2 of IS: 8130/1984. 4.3 INSULATION:

The insulation shall be cross linked polyethylene conforming to the requirement given in Table-1 of IS:7098(Part-II)/1985.

4.4 SCREENING:

The screening shall consist of one or more of the following:

i) Non-Metallic semi conducting tape. ii) Non-Metallic semi conducting compound and ii) Non-Magnetic Metallic tape wire, strip or sheath.

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4.5 FILLERS AND INNER SHEATH: 4.4.1 The filler and inner sheath shall be of the following:

a) Vulcanized or Un-vulcanized rubber or

b) Thermoplastic material.

4.4.2 Vulcanized or Un vulcanized rubber or Thermoplastic material used for

inner sheath shall not be harder than XLPE and PVC used for insulation and outer sheath respectively. The filler and inner sheath material shall be chosen to be compatible with the temperature rating of the cable and shall have no deleterious effect on any other components of the cable.

4.4.3 The Central hole / void, if any, of the cable shall be invariably filled with

suitable filler material so that there is no gap in the center. 4.5 ARMOURING:

4.5.1 The Armouring shall be of Galvanized Steel Strip.

4.5.2 Galvanized steel strips shall comply with the requirements of IS:3975/1979 with

latest amendments. 4.6 OUTER SHEATH:

The outer sheath shall be of Poly Vinyl Chloride (PVC) compound conforming to

the requirement of type ST-2 of IS:5831/1984. 5. CONSTRUCTION:

5.1 CONDUCTOR:

The Conductor shall be of stranded construction complying with Class-2 of IS:8130/1984. The aluminium shall be reasonably uniform in size and shape and its surface be free from any sharp edges.

5.2 CONDUCTOR SCREENING:

The conductor screening shall be provided over the conductor by applying non- metallic semi conducing tape or by extrusion of semi conducting compound or a combination of the two.

5.3 INSULATION:

The Conductor (with screen) shall be provided with cross linked polyethylene (XLPE) insulation applied by extrusion. The insulation shall be so applied that it fits closely on the conductor (or conductor screening) and it shall be possible to remove

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it without damaging the conductor. The thickness of insulation and tolerance of thickness of insulation shall be as per Clause No.11 of IS:7098 (Part-II)/1985.

5.4 INSULATION SCREENING:

5.4.1 The insulation screening shall consist of two parts namely metallic and non-

metallic.

5.4.2 Non-metallic part shall be applied directly over the insulation of each core and shall consist of either a semi conducting tape or extruded semi conducting or a combination of the two or either material with a semi conducting coating.

5.4.3 Metallic part shall consist of either tape or braid or concentric serving of wires

or a sheath should be non-magnetic and shall be applied over the non metallic part.

5.5 CORE IDENTIFICATION:

The core identification shall be done as per Clause-13 of IS:7098 (Part-II)/ 1985.

5.6 LAYING UP OF CORES:

The Cores (with screening) shall be laid together with a suitable right hand lay. Wherever, necessary the interstices shall be filled with non-hygroscopic material.

5.7 INNER SHEATH (COMMON COVERING):

The laid up core shall be provided with inner sheath applied either by extrusion or by wrapping. However, application of inner sheath by EXTRUSION shall be preferred. It shall be ensured that the shape is as circular as possible. The inner sheath shall be so applied that it fits closely on the laid up cores and it shall be possible to remove it without damage to the insulation. The thickness of inner sheath shall be as per Clause No.15.3 of IS: 7098 (Part-II)/ 1985 (with latest amendments)

5.8 ARMOURING:

The armouring shall be applied over the inner sheath. The Galvanized Steel Armoured strips shall be applied as closely as possible with a coverage of not less than 90%.

The direction of lay of the Armour shall be left hand. A binder tape may be applied on the armouring. The dimensions of the galvanized steel strips shall be as specified in Table-4 of IS:7098 (Part-II)/1985. The joints in Armour strips if any shall be made by brazing or welding and the surface irregularities shall be removed. A joint in any strip shall be at least 300 mm. from the nearest joint in any other armour strips in the completed cable.

5.9 OUTER SHEATH:

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5.9.1 The outer sheath shall be applied by extrusion over the armouring. The

colour of outer sheath shall be black.

5.9.2 The thickness of the outer sheath shall be as per Clause No.17.3 of IS: 7098 (Part-II)/1985 with latest amendments.

6.0 TYPE TESTS:

6.1 The material offered, shall be fully type tested as per relevant standard of specification of IS:7098 (Part-II/1985) amended up to date. The bidder must furnish type test reports of similar rating & design of tendered material. The following shall constitute type tests:

a) Tests of Conductor:

i) Annealing test (for copper) ii) Tensile test (for aluminium) iii) Wrapping test (for aluminium) iv) Conductor Resistance test

b) Tests for armouring wires/strips. c) Tests for thickness of insulation and sheath. d) Physical tests for insulation:

i) Tensile strength and elongation at break. ii) Ageing in air oven. iii) Hot test.

iv) Shrinkage test. v) Water absorption (gravimetric).

e) Physical test for outer sheath:

i) Tensile strength and elongation at break. ii) Ageing in air oven. iii) Shrinkage test.

iv) Hot deformation,

f) Partial discharge test. g) Bending test.

h) Dielectric power factor test:

i) As a function of voltage. ii) ) As a function of temperature.

i) Insulation resistance (volume resistivity test). j) Heating cycle test.

k) Impulse withstand test. l) High voltage test.

m) Flammability test.

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6.2 However, the purchaser reserves the right to demand repetition of same orall

the type tests in presence of purchaser’s representative.

6.3 The bidder must also clearly indicate various testing facilities available at their works for testing the material as per relevant standards. In case of otherwise particulars of the place where such testing is proposed to be conducted during the course of inspection shall be indicated with the offer.

7.0 INSPECTION (TEST BEFORE DISPATCH):

7.1 The inspection may be carried out by the purchaser at any stage of manufacturer. Acceptance of any equipment / material under this specification by the purchaser shall not relieve the supplier of his obligation of furnishing equipment in accordance with the specification and shall not prevent subsequent rejection if the equipment/material is found to be defective. The following Acceptance tests as per Clause No.18.2 of IS:7098(Part-II)/1985 shall be conducted in presence of the purchaser's authorized representative / agency on each lot of offered cables:

i) Tensile Test.

ii) Wrapping Test. iii) Conductor Resistance Test. iv) Test for thickness of insulation & sheath. v) Hot Set Test for insulation.

vi) Tensile strength & elongation at break test for insulation and sheath. vii) ) Partial Discharge Test (for screened cables only). viii) High voltage test and ix) Insulation resistance (Volume resistivity) Test. x) Test for Armour:

a) Verification of Dimension of Strip. b) Tensile Strength & elongation at break. c) Uniformity of Zinc Coating. d) Weight of Zinc Coating. e) Winding Test on Armour. f) Resistivity Test on Armour.

Cold impact test for outer sheath (IS:5831/1984) shall constitute the optional test and shall be conducted on first lot of the offered cables of each size as per Clause No.18.4 of IS:7098(Part-II)/1985.

7.2 ROUTINE TEST:-

The following shall constitute routine tests: a) Conductor resistance test b) Partial discharge test c) High voltage test.

The bidder shall furnish Packing list mentioning serial Nos. of Drums, length in each drum, gross weight of drum without lagging alongwith inspection offer

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duly signed by the authorized representative of the firm. The purchaser reserves the rights to insist for witnessing the acceptance / routine tests of the bought out items.

7.3 At least 5% of total numbers of drums subject to minimum of two (2) in the lot put up for inspection shall be selected at random to ascertain the length of cable by the following method. “At the works of manufacturer of the cable shall be transferred from one drum to another for checking any manufacturing defects in the cable, at the same time measuring its length with the help of the graduated pulley and cyclometer. The difference in average length thus obtained from the declared length by the supplier in the packing list shall be applied to all the drums if the cable is found short during checking the sample lot (s).”

7.4 The supplier shall present the latest Calibration Certificate(s) of testing instruments / equipments to be used for the testing of the material covered in the Purchase Order to the authorized inspecting officer/ inspecting agency of the purchaser. The testing instruments/ meters/ apparatus etc. should be got calibrated by the supplier from time to time from Govt. Laboratory or any independent test laboratory/house having valid accreditation from National Accreditation Board for Testing and Calibrating Laboratories for the testing equipments / original manufacturer having trace ability to NABL/NPL or equivalent.

7.5 The calibration certificate(s) should not in any case be older than one year at the time of presenting the same to the inspecting officer/ inspecting agency of the purchaser. The testing instruments/ equipments should be duly sealed by the Calibrating Agency and mention thereof shall be indicated in the calibration certificate(s).

8..0 TEST CHECKING OF MATERIAL: i) Sample drums from the material received at stores shall be selected for

testing at CTL as per sampling plan given hereunder in presence of firm’s representative.

ii) The selected sample drum for CTL testing shall be identified by the seals

provided by Inspecting Officer / Inspecting Agency during pre-dispatch inspection at firms works and these sealing details shall be invariably mentioned in the selection Memo by the nominated officers of Nigam.

iii) SAMPLING: One number Drum out of each lot / sub-lot of 25 Nos. Drums or part thereof for the material received in Stores of Nigam. iv) TESTS: The following tests shall be carried out as per relevant clause of latest IS on

each selected drum by drawing sample of 10 Mtr. at CTL from random distance during re-winding:

a) Rewinding test (Measurement of Length) & Checking of Manufacturing defects. b) Measurement of Resistance of conductor. c) Tensile strength & Elongation at Break Test for Insulation & Sheath d) Test for Thickness of Insulation & Sheath e) Hot Set Test f) Test for Armour: i) Verification of Dimension of Wire / Strip. ii) Tensile Strength & elongation at break. iii) Uniformity of Zinc Coating. iv) Weight of Zinc Coating.

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v) Winding Test on Armour. vi) Resistivity Test on Armour. g) Verification of Marking

In addition to above tests remaining acceptance tests as per relevant IS shall also be conducted at CTL provided the testing facility is available at CTL for these tests time to time. Only those tests shall be conducted for which testing facilities are available in NIGAM’s Lab. v) CRITERIA FOR ACCEPTANCE: a) If the measured of conductor resistance of the sample(s) exceeds beyond2% as

per the resistance specified in the contract, the material shall be rejected and the same shall have to be replaced by the supplier.

b) If the measured conductor resistance of the sample(s) exceeds the value specified in the contract but does not exceed by more than 2% of the resistance value specified in the contract, the material contained in the lot / sub-lot to which the sample belongs shall be accepted with a deduction @ 1.5% of the cost of cable for increase in resistance for every 1% or part thereof.

c) If the sample(s) fails in any other test, the material shall be rejected and shall have to be replaced by the supplier.

e) The results of measurement of length test shall be made applicable to all drums contained in each lot / sub lot by making deduction of less length of cable in a Sample Drum.

9.1 IDENTIFICATION: 9.2 The manufacturer shall be identified throughout the length of cable as per Clause

No.20.1 of IS:7098(Part-II)/ 1985. 9.3 The cable code employed shall be as per Clause No.20.3 of IS:7098 (Part-II) /1985.

10.0 EMBOSSING: The cable shall also be required to be embossed with the word `Name of manufacturer or Trade name, ELECTRIC/ Voltage Grade/ NAME OF DISCOM/ TW-IPDS/TN cable code, size of cable at every meter length for which no extra charges shall be paid. The cable should be ISI marked & same should be embossed on the outer sheet of every meter length of HT Cable. 11. MARKING: The progressive length of cable in meter shall be marked on the outer sheath of every meter length of HT Cable. 12. STANDARD LENGTH: The cable shall be supplied in standard length standard length of 500 Mtrs in one drum for size 11 KV, 3CX120 Sq.mm & 11 KV, 3CX70 Sq.mm. 13. A tolerance of (+/-) 5% shall be allowed on standard length. 14. GUARANTEED TECHNICAL PARTICULARS : The bidder shall furnish guaranteed technical particulars

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TECHNICAL SPECIFICATION FOR SUPPLY OF 400 AMP. & 200 AMOP LT DISTRIBUTION KIOSK SUITABLE FOR 250/315 KVA & 63/100 KVA DISTRIBUTION TRANSFORMERS

1. INTRODUCTION: This section describes the objective and scope of work for design, manufactured, testing and supply of LT Distribution kiosk with all accessories.

2. OBJECTIVE: The objective is to develop an efficient and accidental free distribution system in the jurisdiction area of Jaipur Vidyut Vitran Nigam Ltd.

3. APPLICABLE STANDARDS:

a. IS :13947/1993 (Part 3)/IEC:60947 (Pt.3) for Isolator (Switch Disconnector)

b. IS: 13947/1993 (Part2)/ IEC:60947 (Pt.2) (amended upto date) for L.T. MCCBs.

c. IS: 8623/1993 (amended upto date) for enclosure Box & for degree of protection provided by enclosures of electrical equipments.

d. IS:4237/1982, IS:8623/1993 (amended upto date) – for general requirement of L.T. Switchgear

4. MANUFACTURE/CONSTRUCTION OF LT DISTRIBUTION KIOSK:-

L.T. Distribution kiosk will have Isolator/Switch Disconnector as incomer and single phase MCCBs & Link Disconnector on outgoing side with necessary interconnecting Bus Bars/Links.

Standard General Arrangement of Isolator/Switch Disconnector, MCCBs & Link disconnector, Neutral Link Bus Bars, connecting links, Cable termination arrangement etc inside the LT DISTRIBUTION KIOSK is shown in the enclosed drawing for LT Distribution kiosk suitable for 250/315 KVA & 63/100 KVA Distribution Transformers.

5. INCOMER CIRCUIT

ISOLATOR (SWITCH DISCONNECTOR)

The Isolator shall be of heavy duty, quick make and quick break type with Arc Chute feature. The Isolator for 400 Amp. & 200 Amp. L.T. Distribution Kiosk should have Short Circuit rating of at least 20 kA for one second & 4 kA for two second respectively to withstand the short circuit fault level in our distribution system.

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Each LT DISTRIBUTION KIOSK shall have following rating of triple pole isolator depending upon the capacity of Transformer for which it is to be used.

Sr. No.

Rating of Transformer

Rating of triple pole isolator

No. of triple pole isolator

1 250 / 315 KVA 630 Amp. 1 No.

2 63 / 100 KVA 200 Amp. 1 No.

The bidder have to indicate makes and types of isolator and submit the complete type test report of the isolator as per specification, along with the offer and the isolator to be provided in the LT distribution KIOSK shall be conforming to our specification.

Isolator should be front operated triple pole type. No separate enclosure is required if the casing of non tracking heat resistant insulating material is provided. The isolator shall be of rebutting construction for operation. The handle of the isolator should be detachable easily for security purpose while working on L.T. lines. The characteristics of Isolator shall be as follows:-

Sr. No.

Characteristic 400 Amp. L.T. Distribution Kiosk

200 Amp. L.T. Distribution Kiosk

1 Rated Operational current 630 Amp 200 Amp

2 Mechanism Manual quick make quick break

Manual quick make quick break

3 Standard applicable IS:13947/1993/ IEC 60947 Pt.3 amended up- to-date

IS:13947/1993/ IEC 60947 Pt.3 amended up-to-date

4 Utilization category AC-23A AC-23A

5 Mechanical Endurance As per IS As per IS

6 Electrical Endurance As per IS As per IS

7 Rate duty Uninterrupted Uninterrupted

8 Making/Breaking capacity Not less than the requirement of AC-23A category.

Not less than the requirement of AC-23A category.

9 Rated Short Time withstand current

20 kA for one second 4 kA for two second

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The terminal connector strips of the isolator shall be projecting out of isolator for minimum length of 80 mm, on cable connection side and 60 mm, on bus bar side as shown in the drawing. The cross section of the strips shall be 30x5 Sq.mm for 63 KVA & 50x6 sq. mm for rest on outside of the isolator and length & cross section inside the isolator shall be provided as per design. The material shall be EC grade tinned copper. The terminal strip shall be continuous from the point of contact separation.

All nut bolts used for assembly and connections shall be of nonmagnetic stainless steel only.

6. OUT GOING CIRCUITS:

6.1(a) MCCBs

Any make of MCCB offered by the firm will be acceptable subject to having successful type test reports.

TIME CURRENT CHARACTERISTICS:-

The L.T. MCCBs shall have the following time current characteristics: MULTIPLE OF NORMAL TRIPPING TIME

CURRENT SETTING

1.05 More than 2.5 hrs.

1.2 More than 10 minutes and less than 2 hrs.

1.3 Less than 30 minutes

1.4 Less than 10 minutes

2.5 Less than 1 minute

4.0 Not less than 2 seconds

5.0 Less than 5 seconds

12.0 Instantaneous (less than 40 milli seconds)

For above time/current characteristics reference calibration temperature of the breaker shall be 50 degree C. Deration, if any upto 60 degree C ambient temperature shall not exceed 10 % of the current setting indicated above.

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Each LT DISTRIBUTION KIOSK shall have 3 Nos. of single pole MCCBs per circuit to control and protect outgoing circuits. MCCB shall be conforming to our specification and relevant ISS.

The bidder have to indicate makes & type of MCCB and submit the complete type test reports of the MCCB as per IS:13947/1993 for test sequence I, II & III complete with certified diagram/ Oscillograms and approved drawing from NABL approved Laboratory along with offer. The successful bidder shall furnish detailed type test reports of MCCBs to be used by them, for our approval. The colour of MCCB casing for 63/100 KVA L.T. Distribution Kiosks shall be brown and for 250/315 KVA LT DISTRIBUTION KIOSK shall be Gray colour.

The MCCBs shall be manually operated type and shall have quick make quick break mechanism. The detailed specification for MCCBs shall be as under:-

1. KVA rating 250/315 63/100

2. Rated current 200 A 200 A

3. No. of Circuits 4 Nos. 2 Nos.

4. Fixed overload release setting (Amp.) 160 A 60 A/ 90 A

5. No. of poles 1 Ph 1 Ph

6. Rated service short circuit breaking capacity(KA) which is equal to ultimate breaking capacity as per IS (Ics = Icu= 18 (KA) or more). (The sequence of operation for this test shall be O-t-CO-t-CO, and t=3 min.) The test shall be done at 240V at 0.4 PF. Voltage rating phase to phase 415V and phase to earth 240V.

13947 Pt.III(1993) 18 KA or

more

13947 Pt.III (1993)18 KA or more

7. Power factor for short circuit(Max.) 0.4 (lag) 0.4 (lag)

8. Utilization category A A

The Terminal Connector strips of the MCCB shall be projecting out of the MCCB for minimum length of 40 mm on Link Disconnector side and 60 mm on busbar side as shown in the drawings. The cross section of the strips shall be 30x3 sq. mm on outside of the MCCB and the length and cross section inside the MCCB shall be

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provided as per design. The material shall be EC grade tinned copper. The terminal strip shall be continuous from the point of contact separation.

All nut bolts used for assembly and connections shall be of non-magnetic stainless steel only.

The rated service short circuit breaking capacity as specified in at Sr.No.6 above, shall be based on the rated service short circuit test carried out at specified power factors. For the purpose of this test, the following operation sequence shall be followed.

Break-3 minutes interval-make-3 minutes interval make break.

While the above stipulation regarding the test power factor and the sequence of operation shall be binding, the other procedure for making the short circuit test and circuit etc. shall generally be in accordance with the Indian standard applicable to the type of circuit breakers under test. MCCBs should have locking facility in ‘off’ position.

The MCCB shall directly be purchased from the manufacturer or the authorized dealer or stockiest. The routine & acceptance test on MCCB shall be carried out at the works of original manufacturer. However, in every case of purchase of MCCB the delivery shall be from the manufacturer’s godown for which a copy of bill shall be given to inspecting officer at the time of inspection.

Single pole MCCB is to be provided with over load trip release with inverse time current characteristics for overload protection and magnetic trip release for instantaneous tripping in the wake of Short-Circuits.

These MCCB’s shall be confirming to IS 13947/1993 or any other relevant ISS/IEC as amended upto date. The rated un-interrupted current of MCCB shall be 200 Amp. with the overload release set at 160 Amp for 250/315 KVA Distribution Transformers and rated un-interrupted current of MCCB shall be 200 Amp. with the overload release set at 60 A/ 90 A for 63/100 KVA Distribution Transformers.

The MCCB’s shall be marked with ‘Brand Name’ of manufacture and Ics in KA by embossing only whereas other particulars may be marked as per the manufacturers standard practice.

The contacts of MCCB should be self-wiping type so as to keep the contacts clean and milli-volt drop low.

6.2 LINK DISCONNECTOR: Link Disconnector of suitable capacity shall be provided

between outgoing terminal of MCCB & cable connection as shown in the drawing to facilitate mechanical breaking of the circuit.

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Each LT DISTRIBUTION KIOSK shall have 3 Nos. of Link Disconnectors in each outgoing circuits.

The bidder has to indicate the Makes and Types of Link Disconnector offered.

The base of the Link Disconnector shall be of non tracking, heat resistant insulating material of superior electrical and mechanical properties equivalent to Dough- Moulding Compound (DMC) etc. upto 200 volt for 400 Amp. The Link Disconnector shall be sturdy in construction and easy in operation. The link of Link Disconnector shall be of tinned plated E.C. grade copper. The construction of the Link disconnector shall be such that it shall be hinged type on cable connection end and dis-connectable at the MCCB end. The disconnection will be with the help of special handle/puller. One handle/puller shall be supplied along with each LT DISTRIBUTION KIOSK. The terminal connector strips of the Link Disconnector shall be projecting out of Link Disconnector for minimum length of 80 mm on cable connection side and 40 mm on MCCB outgoing side as shown in the drawings. The cross section of the strips shall be 30x3 sq. mm and Cross section of knife edge link shall be 20x4 sq. mm. The material for both the strips and links shall be tinned E.C. grade copper.

These base of Link Disconnector shall be rated for 150 Amp. current for 63/100 KVA and 200 Amp. current for 250 /315 KVA.

All nut & Bolts used for assembly and connections shall be of non magnetic stainless steel only.

7. BUSBARS AND CONNECTIONS: Bus Bars & inter connecting links shall be of anodized Electrolytic grade aluminum as per IS 5082. All bus bars & links should be properly drilled, de-burred and should be provided with durable PVC insulating sleeves, standard Colour code shall be used for different phases. Minimum clearance wherever shown shall be as per General Arrangement drawing attached. Other clearance shall be as per requirement of IS: 4237 amended upto date. The size of Main Bus bars and neutral bus bar for different rating of LT Distribution Kiosk shall be as below :-

Sr. No.

Rating of LT Distribution KIOSK suitable for Transformers of

Size (cross-section) of main Bus- Bar / dropper links

Size(cross- section) of neutral Bus-Bar

1 250 / 315 KVA 2 x (40 x 8 mm) / 30 x 8 mm 60 X 8.5 mm

2 63 / 100 KVA 40 X 6 mm/ 25 x 4 mm 60 X 3 mm

7.1 All busbars and links should be properly drilled, de-burred and preferably brazed to

minimize tearing of joints. Minimum joints preferred.

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7.2 Busbars shall be provided with durable PVC insulating sleeves. Standards colour code shall be used for different phases.

8. ENCLOSURES: 8.1 The circuit breakers, Link Disconnector and Isolator shall be housed in a sheet steel

enclosure with the door closed. The enclosure shall comply with the requirement of IP-43 type as per relevant IS / IEC or the latest version thereof. Access to the circuit breakers including operating handle shall be available only after the enclosure door is opened.

8.2 Four sets of louvers shall be provided to ensure that the temperature inside the enclosure is not substantially different from that of the atmosphere. The louvers shall be provided with perforated M.S. sheet of 1.25 mm welded from inside the LT DISTRIBUTION KIOSK.

8.3 Fixing of circuit breaker inside the enclosure shall be such as to allow free circulation of air at its back and sides.

8.4 The centrally closed doors with “Godrej” type triple position locking arrangement shall be provided. In addition to this, an arrangement for locking the doors by Sturdy rod type door latch shall be provided on outside. Both illustrations are shown in the drawing.

8.5 The enclosure shall be made of sheet steel of not less than 2 mm thickness for 250/315 KVA & 63/100 KVA.

8.6 The enclosure shall be painted with suitable weather proof & corrosion resistant enamel paint after 7 Tank cleaning process both inside & outside. The colour of the inside paint shall be white, while that of the outer paint shall be brown for 63/100 KVA L.T. Distribution Kiosks and gray for 250/315 KVA LT DISTRIBUTION KIOSK. Powder coating followed with 7 tank hot phosphate cleaning process is equally acceptable. In case of Powder coating the colour of inside & outside surfaces shall be same i.e. brown for 63/100 KVA rating and gray for 250 / 315 KVA rating.

8.7 Necessary fixing arrangement shall be provided at the back of the enclosure to ensure proper fixing on double pole structure by means of suitable clamps only for 63 & 100 KVA L.T. Distribution Kiosks.

8.8 Necessary fixing arrangement shall be provided at the top of the Canopy as shown in the drawing to ensure proper fixing on double Pole structure. In addition to this two Nos. M.S. channel of size 75x40x40 shall be provided at the bottom of the enclosure as shown in the drawing for fixing the enclosure on Plinth.

8.9 For all rating of LT Distribution Kiosks i.e. 63/100 KVA & 250 / 315 KVA the top of

the Distribution Kiosks shall be provided with a sloping Canopy such that the rain water is not accumulated on the top. The Canopy shall be of one piece construction. The side members shall be welded at both sides. The Canopy shall

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project over the sides & doors. The sides section shall be folded to a “U” form to make a water drawing channel. Only front opening is required for 63/100 KVA L.T. Distribution Kiosks whereas for other rating of L.T. Distribution Kiosks i.e. 250/315 KVA, the opening shall be on both sides.

8.10 A suitable bimetallic cable termination arrangement with support insulators shall be provided by extending the EC gr. Tinned copper terminals of the incoming Isolator & outgoing Link Dis connector. It shall be such that after fixing relevant cable lugs, clearances and creepages are maintained.

8.11 The 3.15 mm bottom plate shall be, detachable to facilitate easy crimping of lugs to the cable ends and for convenience in making connections. The plate shall be provided with holes suitable for cable sizes indicated. The bottom plate shall be provided with two air vents with perforated M.S. sheet of 1.25 mm thick welded from inside.

812 The flats provided for clamping (at top & bottom) shall have horizontal slots for adjustment & shall be of welded construction and the welding should be on all sides.

8.13 Required no. of knock out holes should be provided on the bottom plate. Suitable size of PVC cable glands should be provided for these holes.

8.14 Instruction leaflet in HINDI should be provided as sticker in the LT DISTRIBUTION KIOSK door from inside as per Nigam’s specification.

8.15 All the knock out holes shall be of size suitable to enter single core cables having

sizes as mentioned in Clause 10.

8.16 The Danger marking with fluorescent paint shall be provided on one door and a danger plate shall be riveted on another door, on front side.

8.17 The bimetallic lugs of adequate size required for termination of cables on Isolator and Link disconnector at the incoming and outgoing terminals and neutral link shall be provided. The bimetallic lugs shall be as per enclosed specification & of Make approved by the Nigam.

8.18 Minimum 3 Nos. Hinges per door made of heavy duty MS Sheet of minimum length of 75 mm shall be provided from inside.

8.19 All joints for current carrying parts shall be made using non-magnetic stainless steel bolts, 2 nuts & spring washers. The nuts and bolts should be of hexagonal type with groove for bolt.

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9.0 CABLE TERMINATION: Suitable lugs for Incoming and outgoing feeders for different

rating of LT Distribution KIOSK as below :-

Sr. No.

Rating of LT Distribution kiosk suitable for Transformers of

Incoming cable size Outgoing cable size

1 250 / 315 KVA 3.5 X 300 / 400 sq. mm Single core 4 nos. 150/ 185 sq. mm

2 63 / 100 KVA 3.5 X 120 / 150 sq. mm Single core 4 nos. 50/ 70 sq. mm

10. FINISH OF LT DISTRIBUTION KIOSKS:

10.1 All sheet metal works shall undergo the 7 tank chemical and mechanical cleaning process before final paint. Two coats of red oxide and two coats of final paints shall be applied. Colour of outside/inside surface shall be mentioned in this specification.

10.2 Electrostatic painting with oven drying will also be acceptable.

10.3 All other metal parts used in the LT DISTRIBUTION KIOSK’s shall be treated as under.

M.S. parts such as Bolts& Nuts, washers etc. : Electro galvanizing of Zinc

except forbus bar & links.

11. SAFETY ARRANGEMENTS: Two earthing studs of galvanized M.S. 50x12 mm shall be provided for external earth and internal neutral connections. These should be complete with plain washer, spring washer, nuts etc. Earthing studs must be welded to prevent removal of the same from the LT DISTRIBUTION KIOSK.

12. TESTS & TEST CERTIFICATES: The routine and acceptance tests of MCCB as per relevant IS and this specification shall be carried out at the original manufacturer’s works. In case of brought out items, such as Isolator, Link Disconnector etc., the test certificates of original manufacturer shall be produced to the inspecting officer and shall be enclosed with the inspection report.

12.1 Routine Test: (carried out on LT DISTRIBUTION KIOSK’s)

a) Overall dimensions checking b) High voltage test as per relevant IS. c) Operation test on MCCB/ Isolator /Link Disconnector.

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12.2 Acceptance Tests (on complete LT DISTRIBUTION KIOSK):

Following tests shall be carried out as acceptance tests in addition to routine tests as per sampling plan i.e. 1 no out of every lot of 50 or part thereof.

i) Insulation Resistance tests ii) Temperature rise test on one sample of each rating : Temperature rise test will

be carried out on complete LT Distribution KIOSK with all equipments & accessories mounted inside as per provision of IS : 8623 , part – I -1977.

This test shall be carried out on LT DISTRIBUTION KIOSK as well as MCCB & link Disconnector Separately.

iii) Time-Current Characteristics: With the stabilized temperature rise as per (ii) above the MCCB should be tested for time current characteristics at 1.05 & 1.3 times of overload release setting current and should pass the requirement given in this specification.

iv) All routine test as per clause 13.1. 12.3 Routine & Acceptance Test on MCCB at original manufacturer’s works.

To ensure the quality of MCCB, routine & acceptance tests on MCCBs may be carried out at the works of original manufacturers. Before offering the complete box, the manufacturer should offer the MCCBs for inspection at the works of original manufacturer. The following tests shall be conducted only on samples MCCBs as routine/ acceptance for acceptance of the lot of MCCBs at the works of manufacturer during inspection.

1. Visual examination and overall dimensional checking.

2. High Voltage test at 2.5 KV for one second between:

a)-Main circuit & earth.

b)-Control circuit and earth.

c)-Shorted top and bottom terminals with MCCB in open conditions.

3. Insulation resistance test (IS: 8623) with 1000 V MEGGER between above points of S.N.2.

4. Milli-volt drop (IS:5147)

5. Temperature rise test (conducted one sample of each rating out of 1000 Nos. or part thereof) in which contact resistance (mili volt) shall also be indicated.

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6. Verification of time current characteristics (conducted one sample of each rating out of 1000 Nos. or part thereof).

The criteria for selection of No. of samples and for acceptance of lot shall be on 1% quantity or 10 Nos. samples whichever is more. Before dispatch, the MCCBs shall be inspected and tested by the authorized inspecting officer/Agency of the Nigam at the works of the manufacturer.

The successful testing of all samples in respect of tests mentioned above shall be the acceptability criteria of the lot/sub-lot.

Balance Type test of rating offered relating to all equipments/material as per Specification shall be arranged from first lot (without asking for any delivery extension) from CPRI/ independent NABL accredited Lab.

12.4 TYPE TESTS:

I) ON COMPLETE LT DISTRIBUTION KIOSK a) Temperature rise test: The temperature rise test should be carried out as per IS:

8623-1993. Each feeder shall be loaded to its full capacity along with Incomer Isolator as below:

Capacity of LT DISTRIBUTION KIOSK Suitable for transformer having rating

MCCB(SP) Isolator (SP)

250 / 315 KVA 160 / 160 Amp 630 Amp, 1 No.

63 / 100 KVA 60 / 90 Amp 200 Amp, 1 No.

b) High voltage test as per IS:8623 amended upto date.

c) Short Time Withstand Current Test on distribution LT DISTRIBUTION KIOSK:-The LT DISTRIBUTION KIOSK should be subjected to Short Time Withstand Current Test for value of 4 KA for two second for 63/100 KVA rating and 8 KA for two seconds for 250 / 315 KVA rating all circuit independently. The test should be carried out after by-passing MCCBs.

d) Degree of protection for IP-43 on complete unit.

e) Time/current characteristic test as per clause 13.2 (iii) of this specification as stated above.

II) ON ISOLATOR: All type test on incoming Isolator as per IS-13947/ 1993 (Part-III)/ IEC 60947 amended up to date. Only test report shall be submitted.

III) ON MCCB All type test on MCCB as per IS-13947 amended upto date. Only test reports shall be submitted.

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12.5 TEST CERTIFICATES :The LT DISTRIBUTION KIOSK, Isolator and MCCB offered shall be fully type tested as per relevant IS and this specification .

The bidder must furnish type test reports alongwith bid as per the qualification

requirement of the Tender Specification.

The detailed type Test Reports shall be furnished with relevant oscillogram drawings and certified Drawing of the equipment tested. The purchaser reserves the right to demand repetition of some or all type tests in presence of purchaser’s representative at purchaser’s cost. For this purpose, the tenderer shall quote unit rates for carrying out each Type Test.

13. TESTING & MANUFACTURING FACILITIES: The tenderer must clearly indicate what testing facilities are available in the works of manufacturer and whether the facilities are adequate to carry out all routine acceptance and type tests. These facilities may be verified by JVVNL Engineers or other testing agency , if deputed to carry out or witness the tests in the manufacturer’s works. The tenderer must have all the in-house testing facilities to carry out the acceptance tests on the LT DISTRIBUTION KIOSK.

The tenderer should have following minimum manufacturing facilities in house to prove his reliability as a manufacturer of LT DISTRIBUTION KIOSKs.

i) Power operated shearing machine ii) Power operated press brake.

iii) Power operated power presses

iv) Welding machines,

v) Assembling tools

The tenderer shall furnish detailed process of painting. In case painting is to be carried out from outside agencies, the tenderer shall furnish the facilities available with the sub-contractor.

14. TENDER SAMPLE: The tenderers are required to furnish 1 No. LT DISTRIBUTION KIOSK of either rating as per JVVNL’s specification along with the offer. However, the bidders who have already supplied L.T. Distribution Kiosks of rating 400 Amp. or 200 Amp. against previous tender are not required to furnish sample(s).

15. INSPECTIONAll tests and inspection shall be made at the place of manufacturer. The manufacturer shall afford the Inspector (representing the purchaser), all reasonable facilities, without charge to satisfy him that the material is being

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supplied in accordancewith this specification. All the equipments used in testing shall be calibrated from NABL accredited test lab & shall not be more than one year old.

16. CTL TESTING OF MCCB:-

To ensure the quality of MCCB, routine & acceptance tests on MCCBs may be carried out at the works of original manufacturers. Besides this, dimensional checking on One No. MCCB from each lot at CTL may be carried out by braking the MCCB and matching the same with the internal drawing of type tested MCCB. Payment of the particular lot shall be released only after successful testing at CTL.

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BILL OF MATERIAL FOR L.T. DISTRIBUTION KIOSK FOR 250/315 KVA & 63/100 KVA TRANSFORMER (JVVNL)

S.NO.

ITEM

SIZE

63/100 KVA 250/315 KVA

1 M.S. SHEET 2 MM THICK

2 SWITCH DISCONNECTOR (T.P.) 200A - 1 NO. 630 A - 1 NO.

3

M.C.C.B. (S.P.)

200Amp with overload release set at 60/90 A

-6 NOS.

200Amp with overload release set at 1 60 A

-12 NOS.

4 LINK DISCONNECTOR 150 A-6 NOS. 200 A- 12 NOS.

5 ALU. BUSBAR 40 * 6 MM 2*(40*8 MM)

6 ALU. DROPPERS 25 * 4 MM 38 * 8 MM

7 ALU. NEUTRAL BUSBAR 60 * 3 MM 60 * 8.5 MM

8

COLOUR INSIDE / OUTSIDE IN CASE OF ENAMEL PAINT

WHITE / BROWN WHITE / GREY

COLOUR INSIDE / OUTSIDEIN CASE OF POWDER COATED

BROWN GREY

9 DANGER PLATE AS / DRG. 1 NO.

10 NAME PLATE AS / DRG. 1 NO.

11 FUSE PULLAR 1 NO.

12 P.V.C. GLANDS 2"- 1 NO. 3"- 1 NO.

13 P.V.C. GLANDS 1 1/2" -2 NOS. 2"- 4 NOS.

14 BUSBAR STIFFNER 2 NOS.

LEGENDS:-

1. M.S. SHEET FOR ENCLOSURE 2MM & BOTTOM PLATE 3.15MM THICK. 2. DANGER PLATE AS/SP.- 1 No. 3. NAME PLATE AS/ SP. – 1 No. 4. MCCB (S.P.) 200 A – 12 Nos.(250/315 KVA) & – 6 Nos.(63/100 KVA) 5. ISOLATOR 630 A (T.P.) – 1 No. (250/315 KVA) & 200 A – 1 No. (63/100 KVA). 6. LINK DISCONNECTOR 200 A – 12 NOS.(250/315 KVA) & 150 A – 6 Nos.(63/100 KVA)

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7. Alu. BUSBAR 2x(40x8mm).(250/315 KVA) , 40x6mm.(63/100 KVA) WITH HEAT SHRINKABLE SLEEVES.

8. Alu. DROPPERS 30x8mm.(250/315 KVA) , (25mm X 4mm) X 2 Set.(63/100 KVA) WITH HEAT SHRINKABLE SLEEVES.

9. Alu NEUTRAL BUS BAR 60x 8.5 mm.(250/315 KVA) ,60x3mm.(63/100 KVA) OR EQUIVALENT CROSS SECTION

10. EARTHING BOLTS WITH NUT & PLAIN, SPRING WASHER (GALVANIZED) M12x50 MM – 2 Nos.

11. COLOUR –FOR 250/315 KVA - INSIDE WHITE & OUTSIDE DARK GREY IN CASE OF ENAMEL PAINT.

DARK GREY INSIDE & OUTSIDE IF POWDER COATED. FOR 63/100 KVA - INSIDE WHITE & OUTSIDE BROWN IN CASE OF ENAMEL PAINT. BROWN INSIDE & OUTSIDE IF POWDER COATED.

Min. Clearance

a. 200 mm b. 75,, c. 60mm d. 95mm

All dimensions are in mm.

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TECHNICAL SPECIFIICATION FOR SUPPLY OF (A) 33 KV LINE DP (B) 1.8 METRE LONG MS CHANNEL BRACKET WITH CLAMP (C)1.4 METRE LONG MS CHANNEL BRACKET WITH CLAMP

1. SCOPE

This specification covers fabrication, testing & delivery of fabricated steel items as a complete package, complete in all respect as per GTP/Drawings (to be provided by the purchaser to the successful bidder).

2. STANDARDS :


3. MARKING



4. INSPECTION, TESTING &CHECKING :

The finished product before acceptance shall be subject to inspection in respect of workmanship, checking of dimension/weight & testing as per requirement of relevant IS:2062 (latest amended), approved drawings and bill of material, at the suppliers works if not supported by test certificates of main producers viz. SAIL/TISCO/RINL. The certificate for type test (chemical composition & mechanical properties test) issued by prime producer(s) shall be furnished along with the inspection call to the SE(Proc.), otherwise testing shall be arranged at independent Lab on the cost of supplier. The certificate and relevant invoices shall be in the name of the firm on whom the order is placed by the Nigam. In case bidder use the steel sections manufactured by prime producers then the inspecting officer shall verify and record in the inspection report regarding stamping and mark of prime producers. The certificate(s) in the name of other parties/ sources shall not be accepted and in such cases the tests for chemical and mechanical properties shall have to be arranged in the presence of inspecting officer(s) at recognized lab.

The supplier shall present the latest Calibration Certificate(s) of testing instruments/ equipments to be used for the testing of the material covered in the purchase order to the

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authorized inspecting officer/inspecting agency of the purchaser. The testing instruments/ meters/ apparatus etc. should be got calibrated by the supplier from time to time from independent test laboratory/ house having valid accreditation from National/ Accreditation Board for testing and calibrating laboratories for testing equipments/ original manufacturer having trace ability to NABL/NPL or equivalent.

The calibration certificate(s) should not in any case be older than one year at the time of presenting the same to the inspecting officer/inspecting agency of the purchaser. The testing instruments/equipments should be duly sealed by the Calibrating agency and be indicated in the calibration certificate(s).


(a) Suitable accommodation. (b) Local conveyance between arrival point, place of stay, works and departure

point. (c) The supplier shall assist in arranging return ticket and reservation on the request


5. TESTS

Test before dispatch:- The various steel section/structure before dispatch shall be subject to following test as per IS:2062( latest amendment) at the manufacturer’s works Routine test/acceptance test

i. Dimensional checking and visual inspection ii Weight checking iii Chemical composition test iv Mechanical property test

6. TOLERANCE IN DIMENSIONS :

The tolerance(s) shall be permissible as per IS: 1852: (latest amended). Further the following tolerance(s) on fabricated items will also be allowed.

i) Tolerance in over all length ± 3mm ii) Tolerance in edge dimensions (centre of hole to end) ±2mm iii) Tolerance in holecentre ±2mm iv) Circular holes No tolerance v) Weight Tolerance +2% to (-) 4%


The bidder shall furnish the guaranteed technical particulars of the. Any item of the GTP left unfilled or simply written as per ISS etc. shall be considered as incomplete GTP and such tender is liable to be rejected.

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8. CRITERIA FOR ACCEPTANCE The inspected material should be strictly in accordance to the GTP of the specification otherwise the material shall be treated as rejected and shall not be accepted.

9. WEIGHT



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TECHNICAL SPECIFICATION FOR 33 KV CONTROL AND RELAY PANELS

1.0 SCOPE :

1.1 This specification covers design, engineering, manufacture, assembly, shop testing, inspection and testing before supply and delivery of Control and Relay Panels for 33 KV circuits to be installed at various 33/11KV sub- stations covered under Rajasthan and as detailed hereunder.

1.2 It is not the intent to specify completely herein all the details of the design

and construction of equipment. However, the equipment shall conform in all respects to high standards of engineering, design and workmanship and shall be capable of performing in continuous commercial operation upto the Bidder's guarantee, in a manner acceptable to the Purchaser, who will interpret the meanings of drawings and specifications and shall have the power to reject any work or material which, in his judgement, is not in accordance therewith. The offered equipment shall be complete with all components necessary for their effective and trouble free operation. Such components shall be deemed to be within the scope of bidder's supply irrespective of whether those are specifically brought out in this specification and/or the commercial order or not.

2.0 STANDARDS :

The Relays, associated components and enclosures shall conform to the latest issues of standards as given below, except to the extent explicitly modified in the specification.

Indian Standard No. Title

IS-3231 Protective Relays IS-8686 Static protective relays

IS-1248 General requirements of indicating and integrating meters

IS-2705/1981 Current Transformers IS-4201/1983 Application guide for current transformers

IS-2419 Dimensions of panel mounting and indicating & recording

instruments IS-3156/1981 Voltage Transformers

IS-3043/1966 Code of practice for earthing

IS-8530/1977 MDI

IS-14697-1999 Specification for AC Static Transformer operated watt hour and VAR hour meter 0.2 S and 0.5 S.

IEC-62053-22-2003 Specification for AC Static Watt hour

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IEC-62052-11-2003 meters, class 0.2 S & 0.5 S.

CBIP Technical Specification for AC Static Electrical Report No.88 Energy Meter. revised July, 1996 read with amendment issued (April,99, September,99 and also any other amendment thereafter).

IS-9224 HRC cartridge fuse

IS-3202 Climatic proofing for electrical equipment

IS-345 Code for wiring numbers

IS-6005 Code for practice for Phosphating,Iron andSteel.

IS-6875 Control switches (LV switching device forcontrol and auxiliary circuits.)

IS-375 Marking and arrangement for switchgear Busbar main connection and auxiliary wiring.

IS-1554 PVC insulated cable upto and including 1100 V.

IS-5578 Marking & arrangements for switchgear

IS-11353 bus bars, Main connections and auxiliary wiring.

IS-2147 Degrees of protection provided by enclosures for low voltage switchgear & control gear

IS-5 Colours for ready mix paints

IS-8623 Specification for low voltage switchgear and control

gear assemblies.

IS-13947 Specification for low voltage switchgear and control gear.(Covers degree of protection)

----------------------------------------------------------- 2.1 In case equipment conforms to other International standards which ensure

equivalent or better performance than that specified under clause 2.0 then the English version of such standards or the relevant ex- tracts of the same shall be forwarded with the bid and the salient features of comparison shall be brought out separately in additional information schedule.

3.1 SERVICE CONDITIONS:

Auxiliary Power Supply

Auxiliary electrical equipment shall be suitable for operation on the following supply system:

a) AC Supply 415 V, 3 Phase 4 wire 50 HZ,neutral grounded

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AC supply (230 V single phase) b) D.C. Alarm, control 110 VDC,2 wire.

and protective device

Each of the foregoing supplies shall be made available by the Purchaser at the terminal point for each board for operation of relays/switches and auxiliary equipment. Bidders scope include supply of interconnecting cables, terminal boxes etc. The above supply voltage may vary as below and all devices shall be suitable for continuous operation over entire range of voltages.

i) AC supply: Voltage +/- 10% frequency +/- 5% ii) DC supply: -15% to +10%


4.1 The C&R panels, required at various sub stations can be broadly classified into

following categories of panels : ----------------------------------------------------------------------------------------------------------- S.No. Particulars. Type of panels

Simplex Duplex. ------------------------------------------------------------------------------------------------------------- 1. 33 KV C&R panel for controlling

(a)HV side of 2 Nos. ) A -of 33/11 KV )

transformers )

2. 33 KV C&R panels for controlling B - 2 nos. 33 KV feeder circuits.

----------------------------------------------------------

4.2 The requirement of various sub stations will comprise of one or more of these panels. The simplex panel shall be complete in itself and provided with doors at the back, while the Duplex panels shall be with end doors which shall be provided only with transformer panels,detail of CT ratio with their technical particulars and instrument ranges to be provided .Detial of ratio of voltage transformers and capacitive voltage transformers proposed to be provided.

5.0 GENERAL TECHNICAL REQUIREMENT :

5.1 This specification cover the design, engineering, manufacture, assembly,

inspection and testing before supply and delivery of control and relay board duly mounted with protective relays, metering equipments etc. required for the satisfactory operation of radial and interconnected 33 KV lines, Bus couplers and 33KV side of 33/11KV Power Transformer at various 33/11KV grid sub stations included in the specification to the satisfaction of purchaser.

5.2 The intention of the specification is to provide protective relaying & metering

equipments on control boards enumerated in the specification and to be

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complete in every respect for the functions designated. It is required that the supplier,in accepting the contract, agrees to furnish all apparatus, appliances and material whether specifically mentioned or not but which may be found necessary to complete or test any of the herein specified protective schemes in compliance with the requirements of the specification without any extra charges.

5.3 Considerations may be given to alternatives which the supplier considers

advisable by reasons of his own manufacturing requirements and experience, provided descriptive literature is submitted pointing out the recommended device or arrangement as equal to, or superior to that required by the accompanying specification.

5.4 The each supplier/tenderer should indicate the list of recommended spares and

relays which should be purchased (i.e.P.S. module, spare relays and contacts, tripping relays).

5.5 Each supplier/tenderer should also indicate the list of test kits and test accessories required to test their relays which should be purchased.

5.6 The supplier will give training at the works for the relays which are being supplied first time to protection engineers free of cost and assist them in field for commissioning of these schemes (First five) free of cost.

5.7 RELAYING REQUIREMENTS : 5.7.1 The relay offered by the supplier shall comply with the requirements of latest

issue of ISS:3231 & IS:8686 or relevant BSS or IEC If complying with a specification other than BSS/ISS/IEC then an English translation of the same shall accompany the tender.

5.7.2 Each relay shall be provided with dust tight, removable covers with

glass/clear plastic windows. The relay shall be so arranged that on opening the case, it shall be impossible for any dust which may have collected in or upon the case, to fall on the relay mechanism. The operation of the relays shall be practically free from errors due to normal variation in frequency and wave form and from ambient temperature effects between (-) 5 deg. C to 50 deg.C.

5.7.3 All relay voltage current coils/elements shall be able to withstand the

maximum possible thermal and mechanical stresses likely to be encountered in service, without damaging the coil/element and mechanical parts. Each relay coil/elements shall be vacuum impregnated with an insulating compound and shall be heat and moisture resistant. The continuous electrical rating of all the coils shall be 110%.

5.7.4 The volt ampere burden of the relay coils shall be low and, as per the best

modern design, shall be such that the setting and calibration will not easily get out of adjustment. All contacts shall preferably be made of pure silver and shall be readily renewable and self cleaning type.

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5.7.5 Time delay features which depend upon dash pots or other devices which are appreciably effected by change in temperature or humidity will not be acceptable. Permanent magnets shall be non ageing type.

5.7.6 Terminal blocks shall have bases and barriers moulded integrally with brass

inserts and shall be suitable for 660 volts service, individual studs or screws with retainer type washer for terminals shall be provided for each incoming and outgoing feeders.

5.7.7 All fault detecting relays shall be equipped with operation indicators. In

three phase relays with separate elements, each phase shall have separate indicator.

5.7.8 Annunciation and alarm circuits shall be operated by contacts on an auxiliary

tripping relay or by a separate relay added for that purpose. All tripping shall be done by auxiliary tripping relays fed from seperate D.C. source thereby providing isolation of the relaying circuits from the circuit breaker D.C. control sources. Auxiliary tripping relays for all protections included in this specification shall be hand reset type. Transformer auxiliary protection like winding temperature trip, oil temperature trip, Buch holz trip/alarm and Oil surge trip shall be through auxiliary relays.

5.7.9 All the relays shall be provided with test blocks in panel so designed that the relays may be tested in situ. The relays should have provision of testing either through test block or test plug easily accessible by injecting the voltage/current/frequency (as applicable) from external testing instruments / source without first disconnecting / reenergizing the primary electrical circuit protected by the relays. Facilities for isolating the tripping circuit during such testing shall be also provided.


Relay TTB shall have trip bypass arrangement. The testing facilities provided in the relays shall be specifically stated in the bid.

Necessary test plug etc. as may be required for proper testing shall be included in the contractor's scope of supply. One test plug with five panels or part thereof are to be supplied.

5.7.10 All relays shall be suitable for 5 Amps. rated C.T. secondary current and secondary voltage of 110/Root 3 volts between phase and neutral. The non-directional polarization for earth fault shall, however, be rated for 110V. The normal frequency will be 50 cycles per second.

5.7.11 All devices required for correct operation of each relay shall be provided by

the supplier without extra cost. 5.7.12 For over current & earth Fault protection, only numerical relay shall be provided. In

three phase protection relay, the setting for over-current element shall be 50- 200% (in step of 10%) and for earth fault element from 10 to 80% (in step of 10%). The numerical relay shall have following features:-

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a. Self Diagnosis b. Minimum last five abnormal events recording (over current & earth fault)

including fault level and phase along with date & time. c. On-line display of current. d. Communicable with open Protocol having RS-485 port. e. The relay should contain four shots, three phase, programmable & auto

reclose control feature. The auto reclosing control feature shall only be provided for the 33 KV Feeder Type C&R Panel only.

5.7.13 Based on the results of comprehensive test, the tenderer shall declare the

performance of the protectivesystem in terms of the following :

i) Fault setting. ii) Time of operation. iii) Stability limit.

5.7.14 The bidder must furnish type test reports as per relevant ISS/ IEC along with bid

to suit the environmental conditions of our State, in respect of the relay (of the type and design offered) which should have been type tested in NABL accredited test laboratory in respect of such tests for which the lab has been accredited (for Indian make Relays)/ CPRI/ Nationally accredited testing laboratory (for Foreign make Relays). These type test reports should not be older than three years from the date of opening of bid. Bids without Type Test reports will be treated as Non-Responsive.

5.7.15 MAKE OF RELAYS The following make of relays are acceptable to Nigam:-

i) AREVA ii) ABB iii) EASUN REYROLLE iv) JVS v) SEL vi) ASHIDA vii) C&S viii) MEGAWIN ix) CGL x) STELMEC

Any other equivalent make of Relay shall be acceptable subject to prior approval of this office.

5.8 PROTECTION FOR 33 KV SYSTEM

5.8.1 INCOMER (HV side of 33/11 KV transformer)

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Protection will be provided on 33 KV incomer which includes four pole IDMTL non directional inverse time combined over current & earth fault relay with instantaneous attachment with stabilizing resistance.

5.8.2 FEEDER PROTECTION

Protection of 33 KV feeder circuits against line faults shall be met by four pole IDMTL non directional inverse time combined over current & earth fault relay with instantaneous attachment.

5.9 FAULT/TROUBLE ALARM ANNUNCIATION SCHEME :

5.9.1 .01 Each C/R panel shall be equipped with Annunciation scheme

for indicating all the annunciations required for the trip and non trip alarms as per details given hereunder. Each annunciation shall be clearly labelled to indicate the nature of particular annunciation.

5.9.2 The following switches shall be provided with the annunciator :

i) A common push button switch near the annunciator unit which when pressed shall cancel the audible alarm by means of the alarm cancellation relay. The indication lamps incorporated in the control switch shall remain illuminated, but shall change from flashing to steady glow.

ii) A common reset push button shall be provided. By pushing this button

,annunciation shall be restored to the normal condition. The lamp incorporated in the control switch should not glow after resetting all the protection devices.

iii) A test push button switch shall be provided to illuminate all the lamps of

the associated group. As long as the test switch is held in pressed position all the lamps shall remain illuminated.

5.9.3 Necessary auxiliary relays shall be provided in the annunciator scheme to indicate each trip alarm individually .Each alarm whether trip or nontrip shall have visual as well as audible annunciation.

5.9.4 The visual annunciator alarm shall be in the form of flashing display type

glow pattern. The illuminated facias with inscription on the glass translucent plastic to indicate the operation of particular protection device shall be provided. The window shall remain illuminated till the particular initiating contact is reset.

5.9.5 As regards the audiable indication, the automat ic trip of the circuit breaker

due to the operation of protection relays shall be indicated by sounding of a hooter. All non trip alarms shall be indicated by an alarm bell/ electronic bell.

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5.9.6 33 KV Feeder circuits

Following trip/Non trip alarm shall be provided on each panel controlling two 33 KV feeder circuits.

Trip

i) Over current Feeder I trip. ii) ) Earth fault Feeder I trip. iii) Over current Feeder II trip. iv) ) Earth fault Feeder II trip.

Non trip

i) Trip circuit Feeder I faulty. ii) Trip circuit Feeder II faulty.

5.9.7 33 KV Transformer

Following trip/Non trip alarm shall be provided on each panel controlling 2 Nos. 33 KV Transformer circuits.

Trip

i) Over current HV trip Transformer 1. ii) ) Earth fault HV trip Transformer 1. iii) Over current HV trip Transformer 2. iv) ) earth fault HV trip Transformer 2. v) Buch holz alarm Transformer 1 vi) ) Buch holz alarm Transformer 2 vii) Buch holz trip Transformer 1 viii)Buch holz trip Transformer 2 ix) ) Oil temperature trip Transformer 1 x) Oil temperature trip Transformer 2 xi) Winding temperature trip Transformer 1 xii) Winding temperature trip Transformer 2 xiii)Oil surge relay trip Transformer 1 xiv) Oil surge relay trip Transformer 2

Non trip

i) Trip circuit faulty Transformer 1. ii) Trip circuit faulty Transformer 2. iii) Minimum oil gauge Transformer 1. iv) Minimum oil gauge Transformer 2. v) Oil temperature alarm Transformer 1. vi) ) Oil temperature alarm Transformer 2. vii) Winding temperature alarm Transformer 1. viii)Winding temperature alarm Transformer 2.

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ix) D.C. under Voltage alarm Transformer 1. x) D.C. under Voltage alarm Transformer 2.

5.9.8 It will be responsibility of the supplier to provide all the alarms and annunciation

equipments required for the safe and efficient operation of the sub stations. General description of the alarms required are given but the supplier shall include other alarms that he considers necessary.

5.10 SPECIFICATION OF INDICATING AND INTEGRATING INSTRUMENTS AND

METERS :

5.10.1 All indicating instruments shall be of switch board type back connected suitable for flush mounting and provided with dust and vermin proof case for tropical use and finished in black colour. All fixing screws, nuts and threaded parts shall be designed according to relevant Indian Standards. Ammeters, Voltmeters, HT Trivector Meters, as well as power factor meters shall be square pattern and shall conform to the provisions of the latest edition of IS:2419/1963. Energy meters shall conform to the provisions of relevant IS amended upto date.

All instruments shall have practical means of adjustment of accuracy. The limits of errors for ammeters, voltmeters, Power factor meters and watt meters shall be those permissible for class.1 instruments of switch board type given in IS:1248. The energy meters shall however conform to class.0.5S accuracy. The calibration of the instruments shall function satisfactorily when mounted on steel panels or alternatively magnetically shielded instruments shall be used.

5.10.2 AMMETERS AND VOLT METERS :

All ammeters and voltmeters shall be of moving iron spring controlled type. Ammeters

shall be provided in all the individual feeder panels and transformer control panels to indicate the current in all the phases. The ammeters shall be suitably scaled to indicate the current for all the ratios of current transformers. A phase selector switch with four position shall be used to measure the urrent in all the three phases and in the fourth position the ammeters shall be out of circuit.

The voltmeters shall be provided wherever asked for in the detailed equipment requirement. A phase selector switch with six positions shall be used to indicate the voltage between phases and between phases and earth.

5.10.3 A.C. STATIC H.T. TRIVECTOR METERS :

A.C. Static H.T. Trivector Meter shall be as per latest specification of JVVNL. The

meters shall be located at eye level to facilitate observations of readings correctly.

Purchaser reserves the right to get energy meters separately purchased from other source, installed on the control and relay panels to be supplied by the tenderer under this contract. In that event duly blanked cutout with mounting arrangement and wiring shall be provided on the control and relay panels as per details furnished by the

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purchaser. The price of the control and relay panel shall be reduced corresponding to the unit price given in the tender.

5.10.4 TESTING BLOCKS :

Testing terminals shall be provided for carrying out calibration tests on Energy meters, without disconnecting the connecting leads or removing the meters. The test plug shall be so arranged that when the testing respectable are fitted, the current and voltage are automatically disconnected from the source and injection from the separate source is possible.

5.10.5 Unit prices of each metering and indicating instruments shall be given in

the schedule of prices. For making adjustments in the panel mountings depending upon exact system requirement.

5.11 SPECIFICATION OF CONTROL AND RELAY BOARD

5.11.1 The equipment offered should conform to relevant Indian Standards or

equivalent IEC standards. The references of the relevant standard specifications wherever mentioned in the text of this specification have been given accordingly. Other authoritative standards which ensure an equal or better quality than the standards specified will also be accepted.

5.11.2 The Boards shall comprise of cubicles placed side by side to form

continuous boards. The duplex type shall be mounted back to back and so arranged as to have a corridor in between to provide access to the internal wiring. Hinged lockable access doors shall be fitted at both ends of the corridor and switch boards interior shall be automatically lit by the opening of these doors. The control boards for the same line voltages at each sub-station shall be placed side by side.

5.11.3 For the existing sub stations the tenderer shall ensure the matching of

control & relay boards with the existing ones. The complete details of the existing control & relay panels shall be supplied to the successful tenderer. The following points shall be particularly coordinated

i) The height and depth of the panel shall be perfectly matched. ii) Colour of panels both on exterior and interior shall be matched. iii) ize and appearance of instruments, control switches and indicating lamps

mounted on the front of the panels shall be matched with the existing ones to the extent possible.

iv) The size, colour and disposition of the mimic diagram shall be perfectly matched with the existing scheme.

5.11.4 For other new sub stations, access doors with concealed hinges having a

swing of not less than 1050 mm on full opening of their position shall be

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provided at suitable locations. The equipment specified shall be manufactured in the manner set out and where not set out, to the reasonable satisfaction of the purchaser.

5.11.5 The control and relay cubicles shall be of folded type construction. The front

panels, base frame and door frame shall be manufactured from CRCA sheet steel 10 SWG (3mm) thick, while the side panels, roof and doors shall be manufactured out of 14 SWG (2mm) thick CRCA sheet steel. The bottom of the cubicle frame shall be suitable for erection on flush concrete floor. Evenly spaced grout bolts projecting through the base channels forming members of the frame shall be used for securing cubicles to the floor. The dimensions of control and relay panels where no specific matching is required shall be as follows :

Height : 2312 mm (inclusive of base channel height of 102 mm). Width : 750 mm or suitable to accommodate equipments Depth Duplex panel. : 610+762+610 mm (Corridor width is 762 mm). Simplex panel. : 610 mm

5.11.6 The front panels of all the cubicles shall be detachable and all inter connections

from the control to the relay cubicles and vice verse shall be through terminal connectors. The inter connections shall preferably run underneath the top cover. In order to avoid sectionalizing the leads at two points, the top cover may be provided with hinges on the part.

5.11.7 The complete switch board shall be dust and 1 vermin proof and shall be

suitable for tropical use. All holes and extension windows in the panels shall be blanked and access doors shall be lined with compressible line at the edges. The complete boards shall incorporate all necessary meters, instruments, relays, control switches, indicating lamps, mimic buses, audible and visual alarms, horizontal and vertical wiring supports, earth bars, interior lighting system, terminal blocks, cable glands, fuses, labels, cleats, ferrules, space heaters, automatic semaphore indicators and other necessary equipment. In the relay panels, it will be the responsibility of the supplier to make provisions for the leads to be connected to the nunciator scheme for different trip and non trip alarms. The enclosure shall provide a minimum degree of protection equivalent to IP51 in accordance to IS2147.

5.11.8 All power and control cables will be connected in separate distributing

trenches running immediately, underneath the control & relay panels. The cables will branch off into each cubicle through entry holes in the concrete floor opening in the bottoms of the cubicles. The tenderer shall mark the details of the cable entry holes, glands and position of grouting bolts to enable the purchaser to prepare foundations with pockets for groutingbolts while casting floor.

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5.11.9 PAINTING : All unfinished surfaces of steel panels and frame work shall be sand blasted to remove rust, scale, foreign adhering matter and grease. A suitable rust resisting primer shall be applied on the interior and exterior surface of steel, which shall be followed by application of an under coat suitable to serve as base and binder for the finishing coat.

i) All sheet steel work shall be phosphated in accordance with IS:6005 code

of practice for phosphating iron and steel.

ii) Oil, grease, dirt and swarf shall be thoroughly removed by emulsion cleaning.

iii) Rust and scale shall be removed by pickling with dilute acid followed by washing with running water rinsing with slightly alkaline hot water and drying.

iv) After phosphating thorough rinsing shall be carried out with clean water

followed by final rinsing with dilute dichromate solution and oven drying. v) The phosphate coating shall be sealed with application of two coats of

ready mixed, stoved type zinc chromate primer. The first coat may be "flash dried" while second coat shall be stoved.

vi) After application of primer two coats of finishing synthetic enamel paint

shall be applied. Each coat shall be applied followed by stoving the second coat after inspection of first coat of painting. Generally the exterior colour of paint shall be as per shade 631 of IS5, except where specific matching is required.

vii) Each of coat of primer and finished paint shall be of slightly different shade

to enable inspection of painting.

viii) In case the tenderer proposes to follow any other established painting procedure like electrostatic painting, the procedure shall be submitted along with the tender for purchaser's review and approval.

5.11.10 PANEL WIRING :

5.11.10.1 All wiring other than for annunciation circuits shall be of switch board

type 2.5 sq.mm PVC insulated multi strand tinned copper conductor/ Copper conductor suitable for 660V service and in accordance with relevant Indian Standards. For annunciation and alarm circuits, the wiring will be done with 1.5 sq.mm PVC insulated multi strand copper conductor. Polyvinyl chloride used shall have excellent resistance against burning, moisture, oil and vermin and shall be finished with clear colour. Rubber insulated wiring shall not be acceptable.

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5.11.10.2 The wiring shall be supported by plastic cleats/PVC channels. Wires shall be terminated on to the terminal blocks with annealed and tinned (not soldered) crimp tag termination, separate termination being used for each wire, and the size of termination suited to the size of wire terminated. Wiring shall in general be accommodated on the sides of the cubicles and the wires for each circuit shall be separately grouped.

5.11.10.3 Wires shall not be jointed or tied between terminated points. At the

terminal connections, washers shall be interposed between terminals and holding nuts. All holding nuts shall be secured by locking nuts. The connecting studs shall be secured by locking nuts. the connecting studs shall project at least 6 mm from the lock nuts surface.

5.11.10.4 Bus wires shall be fully insulated and run separately. Fuses and links shall

be provided to enable all circuits in a panel except lighting circuit to be isolated from the bus wire. When ever practicable all circuits in which the voltage exceeds 125 volts, shall be kept physically separated from the remaining wiring. The function of each circuit shall be marked on the associated terminal boards.

5.11.10.5 All wiring diagrams for the control and relay Boards shall be drawn as viewed

from the back of the cubicles and shall be in accordance with the relevant I.S.

5.11.10.6 Wiring connected to the space heaters in the cubicle shall have porcelain

beaded insulation over a safe length from the heater terminals. 5.11.10.7 All wiring inter connecting the front panels with the rear panels of the switch

boards over the access shall be wired in gutters held against the ceiling of corridors by means of screws. As the front and the back panels will be detachable, the interconnection shall be made through suitable terminal connectors securely fixed on the panel.

5.11.10.8 All voltage bus wiring ,audible and non audible alarm bus wiring, A C & D C control supply, bus wiring for panel lighting and such other wiring which runs from panel to panel within the switch board shall be laid out in gutters and shall be suitably screened.

5.11.10.9 All wire shall be suitable for bending to meet the terminal studs at right angle with the studs and they shall not be skewed. Metal cases of all apparatus mounted on panels shall be separately earthed by means of flexible copper wire or strip.

5.11.10.10 The following colour scheme of the wiring shall be used :

i) A.C. three phase circuits Colour

No. 1 Phase Red No. 2 Phase Yellow No. 3 Phase Blue

ii) Neutral Conductor Black

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iii) Connections to earth Green iv) D.C. circuits Grey

5.11.11 FERRULES :

5.11.11.1 Ferrules engraved with the same numbers ,letters and symbols as indicated in

the connection and wiring diagrams shall be provided on the terminal ends of all wires for easy identification of circuits for inspection and maintenance.

5.11.11.2 Ferrules shall be of strong and flexible insulating material with glossy finish to prevent adhesion. They shall be engraved and clearly and durably marked and shall not be affected by dampness.

5.11.11.3 Ferrules numbering shall be in accordance with IS:375/1963. The same

ferrule number shall not be used on wires in different circuits on a panel. 5.11.11.4 All points of interconnection between the wiring carried out for

equipments for different suppliers, where a change of number can not be avoided, double ferrules shall be provided on each wire with appropriate numbers on the changing end. The change of umbering shall be shown on the appropriate connection wiring diagram of the equipment.

5.11.11.5 Alternatively marking of the wires may be done with legible numbers painted

on the wires. 5.11.12 TERMINAL BLOCKS :

5.11.12.1 Terminal block connectors built from cells of moulded dielectric and brass

stud inserts shall be provided for terminating the outgoing ends of the panel wiring and the corresponding incoming tail ends of control cables. Insulating barrier shall be provided between adjacent connections. The height of the barriers and the spacing between terminals shall be such as to give adequate protection while allowing easy access to terminals. Provision shall be made on each pillar for holding 10% extra connections .All blocks shall be shrouded by easily removable shrouds of non inflammable moulded and transparent dielectric materials.

5.11.12.2 The terminal blocks shall be suitable for 660 volts service and for

connection with copper wires. 5.11.12.3 Terminal blocks shall be mounted in such a manner as to afford easy

access to terminations and to enable ferrule number to be read without difficulty. Wire ends shall be so connected to the terminals that no wire terminal number gets marked due to succeeding connections. In other words ferrule numbering at the terminals should be unambiguous and fool proof. Terminal board rows shall be adequately spaced and shall not be less than 100 mm apart so as to permit convenient access to wires and terminals. Lables in the form of engraved plastic plates shall be provided on the fixed portion of terminal boards.

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5.11.12.4 No live metal parts shall be exposed at the back of the terminal boards. 5.11.12.5 All studs, nuts ,bolts screws etc. shall be threaded according to the latest

relevant Indian or equivalent International Standards. 5.11.13 CE HEATERS :

Tubular/Rectangular space heaters suitable for connection to the single phase 230

volts A.C.supply complete with switches located at convenient positions shall be provided at the bottom of each cubicle to prevent condensation of moisture. The Watt loss per unit surface of heater shall be low enough to keep surface temperature well below visible heat. Each cubicle shall also be provided with a switch of appropriate rating for control for space heater.

5.11.14 MIMIC DIAGRAM.

Painted colour bands shall be used for the mimic bus. The Width of mimic diagram and

its colour shall be matched with the existing panel. The mimic shall represent a single line arrangement of the station switch Yard equipment. The colour for showing the 33 KV voltage on the mimic shall be used as green. However where specific matching is not required the color scheme for mimic shall be as under :

33 KV - Brilliant Green - Shade 221 of IS 5 11 KV - Signal Red - Shade 537 of IS 5.

The mimic diagram shall be at the eye level.

5.11.15. SEMAPHORE INDICATORS Automatic ,rotating disc type semaphore indicators for indication of 'Close' and 'open' position of circuit breakers, isolators and earth switches shall be incorporated in the mimic diagram. Other equipments such as transformers, voltage Transformers etc.shall be represented by suitable symbols.

The operating coils of the semaphore indicators shall be continuously rated and shall

be operated from 110 volts D.C.The units will operate satisfactorily between the limits of 80 to 120 percent of rated D.C.voltage. The Semaphore disc shall have a 90 degree angular movement clock wise/counter clock wise to show on/off position of the equipment.

5.11.16 INDICATING LAMPS.:

5.11.16.1 Indicating lamps shall be provided on the control Board to indicate the

following: i) Visual indication of 'on' and 'off position of each circuit breaker. ii) Auto trip indication for each circuit breaker. iii) ring charged indication for circuit breaker. iv)V.T. supply indication on one part of the Panel.

5.11.16.2 Each lamp body shall be of moulded insulation and shall be able to

withstand a high voltage of appropriate value. All lamps shall be suitable for 110 volts D.C.supply and shall have low wattage of

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consumption and shall provide a wide angle of illumination of sufficient intensity for comfortable viewing.

5.11.16.3 The òn' and Òff' position indication lamps shall operate at 230 V Single

phase A.C.supply. Automatic change over contactor for changing the 'on' and 'off' position indication lamps from A.C. supply to D.C.supply shall be provided to keep the lamps in working condition in case of failure of AC supply. Suitable, IVT shall be added wherever there is voltage difference between AC/DC supply.

5.11.16.4 A glass of appropriate colour shall be screwed into the front of the

lamps body. The design of the indication lamps shall be such as to facilitate replacement of burnt lamps. An engraved label indicating the purpose of the lamp shall be provided with each lamp. The tenderer shall quote unit prices for lamps and lenses to enable the purchaser to order certain spare quantity along with the main panels.

5.11.17 SWITCH BOARD LIGHTING : The switch Board interiors shall be illuminated by incandescent lamps connected to a 230 Volts single phase A.C.Supply. The illumination of interior shall be free from hand shadows and shall be planned to avoid any strain or fatigue to the wireman who may be called upon to do work. A door operated button switch shall be provided for control of lighting on both entrances of corridor of duplex C&R panels. In case of simplex panels each cubicle shall have its own interior lumination lamp operated by respective door switch.

5.11.18 TRIP CIRCUIT SUPERVISION :

For continuous supervision of the trip circuits, continuous trip circuit supervision relay

shall be installed. The relay shall operate self reset alarm contact for failure of trip supply and open circuit of trip coil or trip circuit wiring. The relay shall monitor the trip circuit in both close and open position of the circuit breakers.

5.11.19 TITLE PLATES :

A title plate bearing the name and purpose of each panel shall be fixed on the top of each control as well as relay panel.

5.11.20 TEST BLOCKS :

Switch board type back connected test blocks with contacts shall be provided with links or other devices for shorting terminals of CT leads before interrupting the normal circuit for injection from an external source or for inserting testing instruments in the circuit without causing open circuit of the CT. The voltage testing studs shall preferably be housed in the narrow recesses of the block moulding insulation to prevent accidental short circuit across the studs. All test blocks for metering and the relays etc. whenever required, shall be of flush mounting pattern and the number of test blocks being provided on each control and relay panel shall be stated in the tender.

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5.11.21 SAFETY EARTHING :

Earthing of current free metallic parts or metallic bodies of the equipments mounted on the switch boards shall be done with 2.5 sq.mm PVC insulated green coloured copper wire. The two ends of this line shall be provided with crimp tag terminations and connected to a tinned copper earth bar of 25mm x 3mm section running longitudinally at the bottom of the control Board.

The neutral point of star connected secondary winding of instrument transformers and one corner of the open delta connected LV side of voltage transformers, if used, shall be similarly earthed by tails connected with the main earth bar at the switch board earthing system. Multiple earthing of any instrument transformer circuit shall be avoided.

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TECHNICAL SPECIFICATION FOR 11 KV 2 MVAR CAPACITOR BANK WITH ASSOCIATED EQUIPMENTS

1.1 SCOPE :

1. This specification is intended to cover the design, manufacture, assembly, testing at the manufacturer’s works before dispatch, supply and delivery of 11 KV 2 MVAR shunt capacitor banks with associated equipments such as circuit breakers, instrument transformers, isolators, residual voltage transformer, series reactor, control and relay panels etc. for efficient and trouble free operation. The scope of work also includes design of installation, complete erection of all equipments. The work shall also cover supply of civil material like cement, sand metal etc. required for casting of civil foundations for Capacitor Bank and its all associated equipments, supply and laying of armoured copper control cables, supply of earthing materials and provision of earthing including pit digging etc. at each Sub-station wherever these Capacitor Banks are going to be installed.

2. Each Capacitor Bank shall be either individually protected by Internal Fuses in series with each elements in the unit.

2 STANDARDS :

2.1 11 KV 2 MVAR Capacitor Banks shall confirm in all respects to the following

relevant ISS with latest editions and amendments at the time of supply : ------------------------------------------------------------------------------------------------------------

Sr. Standard

No. Reference No. Title

------------------------------------------------------------------------------------------------------------

1. IS-13925 (I) Shunt Capacitor for power systems

2. IS-13118 Circuit Breakers/High voltage alternating current circuit breaker.

3. IS-2705 Current transformers.

4. IS-3156 Voltage transformers.

5. IS-9921 Alternating current isolators(disconnects) and earthing switches.

6. IS-12672/89 Fuses (Internal)

7. IS-3842 Protection relays.

8. IS-2099 Bushing for alternating voltage above 1000V

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9. IS-5561 Terminal Connectors.

10. IS-5553 Reactors.

2. Capacitor banks meeting any other national or international standards which ensure equal or better quality than the standard mentioned above will also be acceptable but in such cases, a copy of standard (English version) adopted, should be enclosed with the tender.


3.2 SYSTEM PARAMETERS :

1. Nominal System voltage 11 KV

2. Highest System voltage 12 KV

3. System Frequency 50 Hz

4. No. of Phases 3

5. System grounding Effectively earthed

6. Auxiliary Power supply

a) A. C. Supply 230V, 1 Ph.2 Wire 50 Hz

415V, 3 Ph.4 Wire 50 Hz

b) D. C. Supply 24 / 110 V, 2 Wire

3.2 EQUIPMENT PARAMETERS

3.2.1 SHUNT CAPACITOR BANK :

1. Nominal system voltage 11 KV

2. KVAR capacity required at nominal 1200system voltage (Min.)

3. a) Rated voltage of Capacitor Banks 12.65 KV

b) Rated output of capacitor bank 1800 KVARat rated voltage.

4. Connection of capacitor bank Single Star having unit protected with internal fuses

5. Rating of capacitor unit 7.3 KV, 200 KVAR

6. No. of capacitor units per bank 9

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7. Capacitor KVAR available at nominal 1587system voltage 8. Creepage distance. 25 mm/KV

9. Power loss Not to exceed 0.2 watt/ KVAR including losses in fuses subject to tolerance as per IS.

3.2.2. CIRCUIT BREAKER :

1. Rated voltage. 12 KV

2. Type. Vacuum

3. Reference standard IS:13118

4. Service / Type Outdoor

5. Nominal current. 800 Amp.

6. Short circuit withstand 18.4 KA current

7. Short circuit withstand 1 sec. current duration

8. Peak short, circuit 50 KA withstand current

9. Operating duty 0-3min. -CO-3min.-CO

10. Insulation level:

a) Impulse withstand voltage 75 KV (peak)

b) One minute power frequency 28 KV rms withstand voltage.

11. Operating mechanism Spring charged motor operating / Electro pneumatic

12. Creepage distance. 25 mm/KV

13. Auxiliary voltage. Volts. DC AC24/ 110 240

3.2.3. ISOLATOR :

1. Rated voltage KV 12

2. Rated continuous current Amps. 800

3. Type. Off load / double break

4. Rated short circuit withstand KA 20current for 1 second.

5. Operating mechanism Manual

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6. Rated peak withstand current. KA 50 7. Basic insulation level KV 75

8. Lightning impulse with stand voltage (KVP)

I) To earth and between poles. 75

ii) Across the isolating distance. 80

9. Power frequency with stand voltage (KV rms)

I) To earth and between poles 28

ii) Across the isolating distance 32

10. Creepage distance 300 mm (Min)

11. Auxiliary switch. 4NO + 4NC contact.

12. Earth blade The isolator shall have to be provided with earth blade with

suitable mechanical inter-locking arrangement.

Also, 1 No. Isolator without Earth Blade is required to be provided. 3.2.4 RESIDUAL VOLTAGE TRANSFORMER :

1. Type Outdoor, 3 Phase, 50 Hz.,Oil filled type

2. Ratio 11 KV/110 - 190 V (3 Ph)

3. Connection. Star/Star - Open delta. 4. Accuracy class :

a) Protection winding 3 P

b) Metering winding 1

5. Rated burden (VA)

a) Protection winding 100

b) Metering winding 100

6. Voltage factor. 1.2 continuous and1.9 for 30 sec.

7. Frequency 50 Hz

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8. Basic insulation level. a) Impulse withstand voltage (KVP) 75

b) Power frequency withstand 28voltage (KV rms).

9. Creepage distance (mm) 300

10. Fuses. On secondary side only.

Note : RVT should be capable of discharging the energy of the capacitor bank and the same should be supported by calculation.

3.2.5 CURRENT TRANSFORMER :

1. Rated voltage (KV) 12 2. Type. Single Phase, Out door oil cooled wound primary type 3. No. of cores. 2 4. No. of primary winding. 1 5. Primary rated current (Amp.) 250-125 6. Secondary rated current. 5 Amps. 7. Rated burden (VA) a) Core. I 15 b) Core. II 15 8. Accuracy class. a) Core I 5 P b) Core. II 1 9. Accuracy limit factor core. I. Not less than 10 10. Instrument security factor core. II Not exceeding 5 11. Rated short time current. 18.4 KA for 1 sec. 12. Insulation level. a) Lightning impulse withstand 75voltage (KVP) b) Power frequency withstand 28voltage (KV rms) 13. Creepage distance. 25 mm/KV

3.2.6. CONTROL AND RELAY PANEL :

1. Title plate. 2. Set of mimic diagram. 3. Set of semaphore indicators showing ON & OFF position of isolators. 4. One circuit breaker control switch. 5. Indicating lamps. 6. One continuous monitoring trip circuit supervision scheme. 7. One suitable scaled flush mounting ammeter / voltmeter with coil rating suitable to CT

secondary. 8. One ammeter selector switch/voltmeter selector switch for reading phase

currents/voltages.

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9. One triple pole IDMT, non-directional combined over current and earth fault relays having two over current elements with 50-200% setting range and one earth fault element with 20-80% setting range of 1 Amp. or 5 Amps.

10. One over voltage protection relay with setting range 110-130% of 110 V (Phase to

phase) operation. 11. Two Nos. neutral unbalance voltage operated relay as per requirement. One for alarm

and other for Trip. 12. One time delay relay for avoiding closing of breaker with time delay of 0-10 minutes

after opening operation.

13. One no volt protection relay with setting range of50-90% of 110V (Phase to phase) operation.

14. One trip/non trip alarm with auxiliary relay and lamps.

15. One alarm scheme for AC/DC failure only if not available in the existing panels.

16. One space heater and switch board lighting.

17. One eight window annunciation scheme as specified.

3.2.7. SERIES REACTOR :

1. Rated voltage (KV) 12 2. Type Outdoor, Air cooled, Single Phase, Dry type, Copper wound 3. Linear characteristic. Upto 1.5 P. U. 4. Rating of reactor (KVAR). 0.2% of capacitor rating for in rush current restriction to

be connected on neutral end. 5. Rated current of Reactor 82.15 Amps. 6. Max. Continuous rating. 130% of rated current of capacitor bank. 7. Short time withstand 16 times of 130% of rated capacity and duration current of

capacitor bank for 3 sec. 8. Basic insulation level : I) Impulse withstand voltage (KVP) 75 ii) Power frequency withstand 28voltage (KV rms) 10. Creepage distance (mm) 300 11. Temperature rise. As per IS:5553 I

3.2.8. POTENTIAL TRANSFORMER :

1. Nominal System voltage 11 KV 2. Highest System voltage 12 KV 3. Insulation Level Line end Neutral end a) Impulse withstand 75 voltage (KV Peak) b) One Minute Power 28 frequency with stand voltage (KV rms) 4. Rated Frequency 50 Hz 5. Transformation Ratio 11KV/110 V

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6. Rated Output 50 VA(VA burden per phase) 7. Class of Accuracy 0.5 8. Rated Voltage Factor 1.2 continuos & time 1.5 for 3 secs. 9. Winding connections a) Primary Star b) Secondary Star 10. Type Out door, 3 phase, 50 Hz Oil filled type. 4.0 GENERAL TECHNICAL REQUIREMENT :

i) All apparatus shall be designed to ensure satisfactory operation under such

sudden variations of voltage as may be met with under working conditions in the system including those due to short circuits.

ii) All material used shall be of the best quality and of the class most suitable for

working under the climatic conditions specified. 4.1 CAPACITOR BANKS :

4.1.1. The capacitor banks shall be complete with RVT, Series reactor, Circuit breaker,

off-load type isolators, instrument transformer, protection equipment, control and relay panels connecting materiel and any other material required for capacitor bank. However, the tenderer should quote for all the equipments covered in this specification.

4.1.2 The capacitor bank shall consist of various capacitor units of ratings as given in

equipment parameters under clause 4.2.1. 4.1.3 The capacitor banks shall be outdoor type suitable for operation in the climatic

conditions as specified in this specification, and mounting on steel racks to be supplied by the tenderer.

5.2. CAPACITOR UNITS :

5.2.1. Each capacitor unit of the bank shall be self contained outdoor type, having single

or two bushing with rating as indicated under clause No. 4.2.1. to give the required total bank capacity at 50Hz. Bushing shall be of porcelain and shall be jointed to the case by cementing or soldering with the lid of container as per standard practice.

5.2.2. The capacitor units should be manufactured using all polypropylene as dielectric

media and non PCB impregnant. The impregnation shall be carried out under high degree of vacuum and the unit shall be totally sealed type.

5.2.3. The chemical properties of the insulating fluid used in capacitor units shall be such

that contamination of the environment from the points of view of bio-degradable, toxity and bio concentration will be minimum.

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5.2.4 ch capacitor unit shall be provided with an internal discharge resistor designedto drain out the residual charge upto 50 volts or less within 10 minutes after disconnection from supply.

5.2.5 Each capacitor unit shall either be individually protected by internal fuses in series

with each of the elements in the unit. 5.2.6. The capacitor units with internal fuses shall comply with the following requirements

a) The internal fuses shall confirm to relevant IEC/ISS.

b) The design of the internal fuses shall be such that residuals from fuse

operation(s)shall not cause deterioration of the impregnating fluid. The fuse assembly shall be such that operation of a fuse under worst condition does not affect the other healthy elements.

c) The fuse shall not melt or deteriorate when subject to inrush current which

occur during the life of the bank. d) The design of the fuse shall be such that it shall isolate only the faulty element and

the operation of fuse does not affect the other healthy elements. e) The design of Capacitor Banks and the protection shall be such that the operation

of Internal fuse upto some extent in the same internal series group shall not cause the tripping of the bank. Tenderer should indicate the number of elementsupto which in the same internal group does not cause the tripping of the bank.

The tenderers shall furnish calculations in evidence of above.

5.2.7 GENERAL REQUIREMENTS :

Internal faults in a unit either individually protected by internal fuses in series with each of the element in the unit shall not cause the over current protection to operate before the operation of the corresponding unit/element fuse. The exception is a breakdown in the insulation between the elements and the container. Tenderer shall furnish calculation of bank rating for successive element failure inside a unit.

5.2.8 Each capacitor unit shall be suitable for continuous operation of 1.3 times rated

current at rated voltage and frequency. This over current factor shall include the combined effect of presence of harmonic and over voltages upto and including 1.1 times the rated voltage.

5.2.9 Terminals and mounting arrangement may be in accordance with manufacture’s

standard practice, but should be proportioned with adequate safety margins. 5.2.10 The containers of capacitor units shall be sheet steel painted with suitable anti-rust

primer paint and the two finishing coats of paints as per the manufacturer’s standard practice.

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5.3 CAPACITOR BANK DESIGN :

11 KV, 2 MVAR, 3 Phase Capacitor Bank shall be single star connected. The capacitor protection shall be through Residual Voltage Transformer (RVT).

5.4 MOUNTING RACKS :

5.4.1 The mounting racks shall be of hot dip galvanised steel sections. Each end of the

rack shall have provision to receive incoming line connection. Sufficient space must be provided between rows in a rack for easy replacement of any capacitor unit.

5.4.2 The racks shall be complete with rack insulators, foundation bolts or any other

hardware etc., for assembly into complete bank. 5.4.3 The height of the racks or capacitor banks shall be such that for making electrical

connections with the other equipments, proper electrical clearance are maintained. 5.5 CAPACITOR BANK SWITCHING CONTROL :

5.5.1 Switching of capacitor banks would be performed by circuit breakers through

remote electrical control from the control room. In addition there would be local manual/electrical control of circuit breakers.

5.5.2 A timer must be included with adjustable setting of 0 to 10 minutes to provide a

time lag before which the bank shall not be again switched on (to avoid closing of the circuit breaker on a trapped charges).

5.6 PROTECTION :

The capacitor bank shall be provided with the following protections :

a) Over current and earth fault protection to cover the faults in the capacitor banks and its

controlling circuit breaker. b) Unbalance protection.

c) Over voltage protection.

d) Under voltage/No volt protection.

Requirement of each of the above protections are described below :

5.6.1 OVER CURRENT AND EARTH FAULT PROTECTION :

Combination of two over current IDMT relays having 50-200% settings and one E/F relay of IDMT characteristic with 20-80% setting shall be used with suitable current transformers.

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5.6.2 OVER VOLTAGE PROTECTION : Over voltage protection shall be provided with an inverse time characteristic. Over voltage relay shall be energized from a VT connected to the main bus bars on the source side of the circuit breaker controlling the Capacitor banks. Setting shall be variable from 110% to 130% in steps of atleast 5% Definite time relay with timer may also be offered.

5.6.3 UNBALANCE PROTECTION :

The unbalance protection shall be provided through voltage operated relay connected across open delta voltage of RVT for capacitor bank connected in single star.

There shall be two relays.

1 No. for alarm.

1 No. for trip. The unbalance protection shall trip the bank when :

The voltage across other healthy elements in a failing units exceed 60% of rated element voltage. (Rated element voltage = Rated unit voltage divided No. of internal series groups), whichever is earlier.

The alarm level shall be set at approximately half the trip level.

The setting of current relay shall be adequately chosen based on CT secondary current and neutral unbalance current and it shall be followed by a time delay through a timer of 0.1 Sec. Inverse time characteristic may be used for voltage operated relay. The protection shall give an alarm only in those cases when the voltage on healthy units due to failure of one or more units rises to 105% and trip the capacitor bank when the voltage rises to 110%.

The tenderer shall furnish the following calculations :

i) Voltage across the open delta of RVT, over voltage across other healthy units and over voltage across other elements for successive internal element failure in a failing unit.

5.6.4 NO VOLT PROTECTION :

No volt protection should be provided to disconnect the bank under no voltage condition. This protection shall be energized from the existing Bus P.T. This protection should not operate in the event of fault on 11 KV lines which may dip the bus bar voltage to 50%. There should be provision for adjustment in setting of voltage and time to coordinate 11 KV lines protection with no voltage protection to avoid mal-operation of no voltage relay under line faulty conditions.

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5.7 ASSOCIATED EQUIPMENTS : The following associated equipments having detailed specification described hereinafter, shall be supplied along with one number 11 KV capacitor Bank. The tender without offering associated equipments shall be considered incomplete.

1) 11 KV circuit breaker 1 No. 2) 11 KV Isolator with Earth Blade 1 No. 3) 11 KV Isolator without Earth Blade 1 No. 4) 11 KV CTs 3 Nos. 5) 11 KV RVT 1 No. 6) Control & Relay Panel for 11 KV 1 No. Capacitor Bank 7) 11 KV Series Reactor 3 Nos. single phase, 8) 11 KV, 3 Ph Potential Transformer 1 No. 9) Mounting & elevating structures of 1 Set suitable height for capacitor bank and associated equipments complete in all respect

NOTE :

Scope of supply does not include the control cables/overhead conductor which shall be supplied/provided by the purchaser. However the sizes of control cables/overhead conductor terminals for all equipments shall be clearly stated in the tender.

5.7.1 CIRCUIT BREAKER :

(i) The circuit breaker shall be Vacuum type suitable for a rapid and smooth interruption of

capacitive and fault currents under all conditions. (ii) The circuit breaker shall be free from re strikes under all operating conditions. (iii) The circuit breaker offered shall be suitable for capacitor bank switching duties of

capacitor bank ratings indicated. (A) OPERATING MECHANISM :

(i) The circuit breaker should be suitable for remote control from the control room

and in addition there should be provision for local electrical/manual operation of circuit breaker.

( ii) The circuit breaker should have a mechanical open/close indicator in addition to the

facilities for remote electrical indication.

(iii) The operating mechanism should be of motor operated or Pneumatically operated type. The mechanism should be trip-free electrically and mechanically. All working parts in the mechanism should be corrosion resistant material and all bearings which require greasing should be equipped with pressure grease fittings. A suitable anti-pumping features should be incorporated in the Breaker.

(iv) The operating mechanism along with its accessories should be mounted in a

weather proof cabinet with hinged doors and located near the breaker or

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accommodated in the steel frame work of the breaker itself. The local control switch and the breaker position indicator should be provided in this cabinet.

(v) The control circuit should be designed to operate on 24/110 V D.C. and it should be possible to adopt it to work on any other required voltage by changing the operating coils of the breaker. Closing coils should be designed to operate satisfactorily at any control voltage from 85% to 110% of the normal voltage. Tripping coils should be designed to operate satisfactorily at any control voltage from 70% to 110% of the normal voltage. However circuit breaker when not carrying current should be capable of operation satisfactorily when the control voltage at the terminals of trip coils is less than 50% of normal voltage.

(vi) A heater alongwith switch should be provided in the cubical for connections to

single phase 240 V AC supply to prevent moisture condensation. (vii) A local/remote switch should be provided in the operating mechanism of the

circuit breaker to cur-off the DC supply to trip or close coils from remote control when the switch is set to local so that the breaker cannot be operated from remote control switch. But trip coils should be so connected that these receive a tripping command from the relays even after the remote control is disconnected.

(viii) Power supply for auxiliaries will be available at 240 V, 1 Phase and 415 V, 3 Phase, 50 cycles.

(x) Necessary cable glands for the cables of the operating mechanism should

be provided along with a large common gland plate. (B) AUXILIARY SWITCHES :

Adequate number of silver coated auxiliary switches (contacts) both of the normally open and normally closed type (along with 6 NO and 6 NC as spare) should be provided in each circuit breaker for use in the remote indication and control scheme of the circuit breaker and for providing safety inter locking. There should be provision to add a few auxiliary switches at a later stage, if required.

(C) INTERLOCKS :

Provision should be made to enable suitable mechanical/electrical, inter-locking for the opening or closing of the isolator.

(D) TERMINAL CONNECTORS :

Requisite number of suitable and matching terminal connectors shall be supplied along

with the breaker. 5.7.2 ISOLATOR CUM EARTH SWITCH :

(i) The isolator shall be triple pole, gang operated having horizontally rotating blades.

The isolators shall be capable of withstanding the dynamic and thermic effects of

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rated short circuit in the closed position. The earthing switches shall be capable of discharging trapped charges of the shunt capacitor banks.

(ii) The isolators and earth switch shall be manually/electrically operated.

Isolators should be provided with ON & OFF indicators for mechanical interlock and padlocking.

(iii) Isolators should be provided with auxiliary switches for their remote position indication on the control panel and electrical interlocking with circuit breaker. Four pairs of NO & NC contacts shall be provided.

(iv) 1 No. Isolator with Earth Switch & 1 No. Isolator without earth switch shall be

required to each capacitor Bank. 5.7.3 CURRENT TRANSFORMERS :

(i) The current transformers shall be of outdoor type, single phase, 50 Hz, oil

immersed, self-cooled type. (ii) The core shall be of high grade, non-aging electrical silicon laminated steel of

lowhysteresis loss and high permeability to ensure high accuracy at both normal and over current.

(iii) The current transformer shall conform to the latest edition of IS-2705. The bushing

shall comply with the latest edition of IS-2099 and 3347. The current transformer shall be complete in all respects including insulating oil, junction box, terminal connectors fixing bolts and nuts and other accessories.

(iv) The current transformers shall be hermetically sealed to eliminate breathing

andprevent air and moisture from entering the tank. These shall be provided with oil level gauge and pressure relieving device capable of relieving abnormal internal pressures. The C.T. shall have two cores, one for metering and other for protection. The saturation factor of metering core shall be low enough (not more than 5) not to cause any damage to the measuring instruments in the event of maximum short circuit current. The rating of the secondary shall be brought out in a compartment on one side of the CT for easy access. The secondary terminal shall be provided with short circuiting arrangement.]

(v) Suitable and matching terminal connectors shall also be supplied alongwith the

current transformers and accordingly the prices may be quoted 5.7.4 RESIDUAL VOLTAGE TRANSFORMERS :

The RVTs shall be 3 Phase, outdoor type, oil filled having ratio 11 KV / 110 V- 190 volts, star/star/open delta connected suitable for neutral unbalance voltage protection of capacitor bank and conforming to IS:3156. The RVTs shall be complete in all respect including mounting and elevating structure and terminal connectors suitable for ACSR DOG conductor. The secondary winding of RVTs shall be connected in open delta for 190 Volt or the voltage necessary for operation of neutral displacement relay based on capacitor unit rating.

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5.7.5 CONTROL AND RELAY PANELS : (i) The control and relay panels shall conform in all respects to relevant Indian

standards. (ii) The control & relay panels shall be of floor mounted indoor free standing cubicle

type. The panel shall consist of fabricated sheet steel enclosures on the sides front rear and top. The rear of the panels shall be in the form of lockable hinged flap door. The front and rear sheets shall be of folded construction for providing rigidity and strength without using any frame work or screwed or bolted sheets steel sections. The front of the panels which accommodates most of the mounting shall be fabricated with sheet of thickness not less than 3 mm. For the rest of the panel which carries no weight of the mounting, sheet steel of thickness not less than 2.5 mm should be used.

(iii) The panels shall be 2315 mm height 750 mm wide and 610 mm deep with door lock

and complete with small wirings, earthing bar, fuses, links, vermin proof fitments, internal panels lighting arrangement, operated by a door switch, a space heater rated 100 watt, 230 V AC with a switch undrilled cable gland plate and 75 mm x 102 mm channel from plinth. The panel shall accommodate the following :

1. Ammeter with selector switch. 2. Voltmeter with selector switch. 3. Circuit Breaker with control switch. 4. Necessary relay and auxiliary relays.

5. Over load mimic display for bus arrangement including semaphore indication for Isolator and Circuit Breaker. 6. Necessary push buttons and switches. 7. Necessary indicating lamps for Circuit Breakers ‘ON’ and ‘OFF’ trip circuit healthy and spring charged indication etc. 8. Alarm Bell. 9. Any other equipment considered necessary to make the panel complete in

all respects. (iv) All the relays should be accommodated suitably in the control panel complete with

necessary indicating instruments, control switches, indicating lamps, wiring, fuses links etc.

(v) The control and relay panels shall be delivered with all relays, instrument switches

indicating lamps etc. duly mounted. (vi) The panels shall be equipped with necessary links and HRC type fuses of good

quality which shall be mounted on sheet steel brackets. Each fuse shall be identified with the suitable engraved plastic label.

(vii) The internal wiring of the panels shall be carried out with PVC insulated multistrand,

flexible cables of 650 V grade, Both ends of wire shall have the numbered plastic ferrules for identification. Panel wiring shall be suitably bunched and clamped to a neat appearance. All panel wiring should withstand 2 KV AC Voltage for 1 min. between conductors and earth.

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(viii) All panel wiring terminations (except for CT & PT) for connecting external apparatus circuit shall be neatly terminated on ordinary terminal blocks. For CT and PT termination, links terminal blocks to be used shall have links for disconnection and plugging in facility for testing purposes. The terminal shall be suitably labeled to identify the outgoing/incoming wires. 20% terminal of each type shall be provided as spare in each panel for future use.

(ix) All the equipments including relays, indicating instruments et. shall be flush

mounted. All mountings shall be provided on the front side. (x) The outside surface of the panels shall be synthetic enamel painted in light grey as

per shade No.631 of IS:5. The inside surface shall be painted with white synthetic enamel paint. Performance will be given to powder coated Panels.

(xi) Each relay, auxiliary relay, instrument, lamps, switches etc. should be identified,

both inside and outside the panel with suitable engraved plastic labels. (xii) MIMIC DIAGRAM :

(a) Mimic diagram and symbols showing the exact representation of the system

complete with symbols and colour strips to represent the buses, semaphore indicators etc. shall be provided in the front of the control panels. The control switches shall be mounted along with the mimic diagram.

(b) Mimic diagram shall be made preferably of anodized Aluminium of approved fast

colour material which shall be screwed on to the panel and can be easily cleaned or of radium strip.

(c) The colour scheme and size of mimic diagram shall be proposed by the tenderer

and will be subject to approval of the purchaser. (xiii) SEMAPHORE INDICATORS :

Automatic semaphore indicators shall be provided for automatic indication in the mimic diagram for the position (open or close) of Isolators with earthing switch. They shall be of two coil type and their operating voltage shall be from station DC supply. They shall also have the supply failure indication during which the disc comes to neutral position when both units of the indicator are deenergised. Semaphore indicators shall be so mounted on the mimic diagram that the close position shall complete the continuity of the mimic. Their strips shall be of the same colour as of the associated mimic.

(xiv) CONTROL SWITCHES :

(a) Control switches shall be pistol grip type preferably with silver to silver contacts of

adequate making, carrying and breaking current ratings and clearly marked to show operating position and shall be suitable for flush mounting with only switch front plate and operating handle projecting out the connections shall be from the back.

(b) The selection of operating handles for the different types of switches shall be as

follows :

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1) Breakers control switches - Pistol grip black.

2) Selector switches - Over or Knob, black (c) Circuit breaker control switches shall be 3 position spring return to neutral type. The

control springs shall be strong and robust enough to prevent inadvertent operation due to light touch. Adequate number of spare contacts shall be provided on breaker control switch for control interlocking, annunciation. Instrument selection switches shall be of maintained contact (stay-put) type. Ammeter selector switches shall have make before break type contacts so as to prevent open circuiting of CT secondaries when changing the position of the switch.

(d) The contact rating of the switches shall be as follows :

Description Contact rating in Amps.

240 V AC 110 V DC 1) Make & carry continuously

10 10

2) Make & carry for 0.5 Sec. 3) Break :

30 30

i) Resistive load 7 7

ii) Inductive load with 7 2 L/R = 40 m Sec.

(xv) INDICATING LAMPS : (a) Indicating Lamp shall be of miniature switch-board type suitable for panel mounting

with rear terminal connections. Lamps shall be provided with series connected resistors preferably built in the lamp assembly to avoid short circuiting of control supply in the event of short circuiting of lamps. The supply for these lamps shall be from DC station battery unless stated otherwise. Lamps covers shall be of screwed type, unbreakable, and moulded from heat resisting material. They shall be translucent to diffuse light. Unless otherwise stated, the lamp covers, shall be coloured as :

1. ‘Red’ for indicating close position of breakers.

2. ‘Green’ for indicating open position of breakers.

3. ‘Blue’ for control supply monitoring.

4. ‘White’ and ‘Amber’ for miscellaneous indications.

(b) Colour caps shall be screwed into the front of lamps body so that colour caps and

lamps shall be replaceable from the front of the panel. Two sets of special tools, if required for replacing bolts and covers shall also be included in the scope of supply.

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All colours covers shall be similar and interchangeable and all lamps be of same type and ratings. Lamps shall be furnished 20% in excess of the actual numbers required and caps shall be furnished 10% excess of actual numbers used for each.

c) The voltage and resistance of lamps shall be as follows :

220 V 5 to 10 W, 4000 to 8000 Ohms (Series Resistor)

110 V 5 to 10 W, 1000 to 2000 Ohms (Series Resistor)

The indicating lamps with resistors shall withstand 120% of rated voltage on a continuous basis.

(xvi) ANNUCIATION SYSTEM ;

a) Alarm annunciation system shall be provided for the control board by means of

visual and audible alarm in order to draw the attention of the operator to the abnormal operating conditions or the operation of some protective device. The annunciation shall be divided into the following two categories.

1) Emergency annunciation.

2) Warning annunciation.

The annunciation equipment shall be suitable for operation on DC supply as specified in this specification.

b) EMRGENCY ANNUNCIATION :

This annunciation is used to draw the attention of the operator when the circuit breaker is tripped automatically. Auxiliary contact for the audible annunciation shall be provided. The visual annunciation shall be by flickering of a respective panel on which the control of the tripped breaker is located. The tripped breaker shall be indentified by the flickering of the corresponding position indicating lamps.

c) WARNING ANNUNCIATION “:

This annunciation is used to draw the attention of the operator to the occurrence of an abnormal operating condition and then the tripping of the circuit breaker. Auxiliary contact of the audible annunciation shall be provided. The visual annunciation shall be flickering of the respective facia window. Certain number of alarm under this category have to be time delayed with time delay adjustable between 2 to 10 seconds. Arrangements for this purpose shall be provided by the supplier.

1. The visual annunciation shall be provided by annunciation ficia flush mounted on

the top row of the control panels. Necessary switching relays for the same shall be mounted inside the panels. The annunciator facia shall be provided with translucent glass or plastic cover plates of white colour with inscriptions in black letters. The

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size of the facia window shall be 30 mm x 25 mm (Approx.). The cover plates of the facia window shall be capable of easy removal to facilitate replacement of lamps. The transparency of covers and wattage of the lamps provided in the facia window shall be adequate to ensure clear visibility of the inscription from the location of the operator’s table in the control room having high illumination intensity. Each annunciation window shall be provided with two lamps in parallel to provided safety against lamp circuit shall include series resistor of adequate rating.

“Acknowledge “ Reset “ and Lamp Test” push buttons for the annunciatiors shall be provided.

The sequence of operation of the annunciator shall be as follows :

Alarm Fault Visual Audible Condition. Contact annunciation

annunciation

1. Normal Open Off Off 2. Abnormal Close Flashing On

3. Acknowledge push button a) Close Steady On Off in pressed b) Open Steady On Off

4. Reset push button pressed a) Close On Off

b) Open Off Off

5. Lamp. Test Push button Open Steady on Off pressed. Or Flashing on On

2. In case of static annunciator scheme, special precaution shall be taken by the

tenderer to ensure that spurious alarm condition do not appear due to influence of external magnetic fields on the annunciator wiring and switching disturbance from the neighbouring circuits with in the panel.

3. Visual and audible annunciation for the failure of DC supply to the panel shall also

be provided and this annunciation shall operate on 240 Volts AC supply with separate fuses. A separate voltage check relay (adjustable setting) for the failure of supply shall be provided and if the failure exists for more than 2-3 secs. a facia shall light (up and the bell shall sound). Alarm will be accepted with accept Push button and can be reset after DC Supply is restored.

(xvii) INDICATING INSTRUMENTS :

1. Indicating instruments shall be flush mounted with anti parallex white circular scales

with black pointer and with black number and lettering. Knoef-edge pointers shall be preferred. Unless otherwise specified the size of all instruments shall be 144 mm x 144 mm and they shall have a circular 240 degree scale.

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2. The dials shall be free from warping, fading and discoloring. Spring controlled instruments shall be provided on front with zero adjuster, capable of being safely handled while the instrument is in service. Instrument covers shall be of shadow proof design, utilizing all available light. They shall also have red marks on the dial corresponding to rated values of the associated primary equipment. The indicating instruments shall conform to IS:1248 and shall have on an accuracy class of 2.0 or better. The design of the scale shall be such that the resolution corresponding to 50% of the accuracy class index is possible.

(xviii) AMMETERS :

All ammeters shall be of taut band type and provided with direct reading triple range scale. The scale value of AC ammeters shall be equal to 1 to 1.3 times the rated primary current of the ammeter element shall be 1.0 Amp. as specified in Section. IV. The ammeters shall withstand 120% of rated current continuously and 10 times the rated current for 0.5 sec. without loss of accuracy.

(xix) TRIP CIRCUIT SUPERVISION RELAYS :

The trip circuits shall be supervised by means of relays. The scheme shall continuously monitor the trip circuit before closing and after closing of the breaker. The scheme shall detect (I) Failure of trip supply (ii) Open circuit of trip circuit wiring and (iii) Failure of mechanism to complete the tripping operation. The relays shall have necessary contacts to be connected to either the alarm bell or to the annunciator available in the control panel for visual and audible indication of the failure of trip circuit.

5.7.6 SERIES REACTOR 11 KV :

1. The Series Reactor 0.2% of capacitor bank rating shall be provided for limiting the

inrush current due to parallel switching of capacitor banks on the same bus. 2. The Series Reactors shall be outdoor, air cooled single phase, dry type, copper

wound.

3. The Series Reactor would be connected towards neutral side of the shunt Capacitor Bank.

4. The Series Reactor shall be complete in all respects including clamps, fixing bolts,

and nuts and other accessories and shall confirm to the latest edition of IS:5553.

5. Complete details of the rating of the reactors, literature and type test certificates for reactors should be furnished along with tender.

5.7.7. POTENTIAL TRANSFORMER :

The potential transformers shall be of outdoor type three phase, 50Hz, oil immersed, self cooled type.

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The core shall be high grade, no-ageing electrical silicon laminated steel of low hysteresis loss and high permeability to ensure high accuracy.

The potential transformer shall confirm to the latest edition of IS:3156.

The bushing shall comply to the latest edition of IS:2099 and 3347. The potential transformer shall be complete in all respect including insulating oil, junction box, terminal connectors, fixing bolts and nuts and other accessories.

The potential transformers shall be hermetically sealed to eliminate breathing and prevent air and moisture from entering the tank. These shall be provided with oil level gauge and arrangement for releasing abnormal internal pressures. The saturation factor of metering core shall be low enough (not more than 5) not to cause any damage to the measuring instruments in the event of fault. The secondary terminal shall be brought out in a compartment on one side of the PT for easy access.

Bimetallic terminal connectors shall be supplied along with the potential transformers. Besides all other necessary fittings with lugs, oil filling hole with cap drain plug with sealing arrangement, inspection cover etc.

5.7.8. MOUNTING AND ELEVATING STRUCTURES :

The mounting and elevating structures of suitable height shall also be provided for capacitor banks and associated equipments. The structures shall be fabricated from suitable steel section and shall be hot dip galvanised. The structures shall be complete in every respect i.e. foundation bolts and other hardwares etc. for assembly. Angle below 50x50x6 size shall not be used for any section of

structure. Bolts & Nuts required for above structures shall not be less than M16 size.

Foundation bolts required shall be minimum size of 25x 300 mm only. 5.7.9 FITTINGS AND ACCESSORIES :

Any fittings or accessories which might not have been mentioned in the specification but which are usual or necessary in the equipment are to be provided by the contractor without extra cost. All equipments must be complete in all respects whether mentioned in the specification or not.

5.7.10.MODE OF CONNECTION FOR CAPACITOR BANK WITH ASSOCIATED

EQUIPMENTS AND STANDARD LAY OUT : The general arrangement for formation of capacitor banks as well as bus arrangement shall be suggested by the tenderer by providing general out line diagram.

6.1 TESTS :


The capacitor units shall be subjected at maker’s works before dispatch, to the following tests as per relevant ISS or IEC Publication (amended upto date).

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(A) ROUTINE TEST AS PER RELEVANT STANDARD :

1 Test for output and capacitance.

2 Voltage test between terminals.

3 Voltage test between terminals and container..

4. Voltage test between terminals and earth. 5. Insulation resistance test.

6 Test for efficiency of discharge device.

(B) TYPE TEST REPORT FOR 200 KVAR, 7.3 KV CAPACITOR UNITS CARRIED OUT

FROM GOVT. LABORATORY SHALL BE SUBMITTED ALONGWITH THE BID INCLUDING THE FOLLOWING TESTS:

1 Test for dielectric loss angle (Power factor).

2 Test for capacitor loss.

3 Thermal stability test. 4 Impulse voltage test between terminals and container.

5 Endurance test as per IS:13925 (Part.II/1994) / IEC TS 60871 Part-I

6.3 TYPE TESTS :

Bidder shall be a manufacturer of Capacitor and should have atleast five years experience in the design, manufacture and supply of 11 KV or above voltage class Capacitor Banks along with associated equipments. The bought out equipment manufacturers should have atleast five years experience in the design, manufacture and supply of 11 KV or above voltage class equipments. The Bidder should enclose the necessary documents towards the qualification alongwith its bid.


All the equipments offered, shall be fully type tested as per the relevant standards. The bidder must furnish type test reports alongwith bid for each equipment carried out at an independent test laboratory except Induced over voltage test on Series Reactor. These type test reports must not have been conducted earlier than five years; from the date of opening of bid. Bids without type test reports will be treated as non-responsive.

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6.5 ROUTINE / ACCEPTANCE TESTS : The following tests for capacitor shall be got conducted in presence of purchasers representative. The number of samples for routine/acceptance test for capacitor shall be in accordance to recommended plan of sampling given in IS:13925

1. Visual examination.

2. Sealing test.

3. Test for output and capacitors.

4. Voltage test between terminals.

5. Voltage test between terminals and container.

6. Voltage test between terminals and earth.

7. Insulation resistance test.

8. Test for efficiency of discharge device.

9. Measurement of tangent of dielectric loss angle and capacitor loss.

The routine/acceptance tests as per relevant ISS shall be conducted at Boughtout item manufacturers works on each unit of Circuit Breaker, Isolator, Current Transformer, RVT, C & R Panel and Series Reactor except Induced over voltage test on Series Reactor.

6.6 TOLERANCE ON TEST RESULTS :

Since Indian Standard IS:13925 or IEC publication allow certain tolerance for the acceptance of losses for capacitors and series reactor respectively. The bidders are requested to indicate whether the figures given for guaranteed losses in schedule of Guaranteed Technical Particulars are with or without such tolerance. If the tolerance are applicable, the limit for the same should be indicated. In absence of any information to this effect, the figures for losses will be increased by 10% in case of shunt capacitors & 15% in case of series reactors. Any change in the figures assigned for the losses will not be permitted after opening of bids & the bid evaluation will be carried out on the basis of information made available at the time of bid opening.

6.7 TEST AT SITE :

The purchaser reserves the right to conduct all test on Capacitors, Capacitor fuses, Circuit Breaker, Isolators, Current Transformer, Residual Voltage etc. after arival at site and the contractor shall guarantee test certificate figures under actual service.

7.0 INSPECTION :

All the tests (as mentioned at Clause 6.4 and inspection shall be made at the place of manufacturer unless otherwise especially agreed upon by the bidder and purchaser at the

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time of purchase. The Bidder shall afford the Inspection Officer (s) representing the purchaser, all the reasonable facilities without charges to satisfy him that the material is being furnished in accordance with this specification. The purchaser has the right to have the tests carried out at his won cost by an independent agency whenever there is a dispute regarding the quality of supply.

The inspection may be carried out by the purchaser at any stage of manufacture / before dispatch as per relevant standard. Inspection and acceptance of any material under the specification by the purchaser, shall not relieve the accordance with the specification and shall not prevent subsequent rejection if the material is found to be defective. The Bidder shall keep the purchaser informed in advance about manufacturing programme so that arrangements can be made for inspection.

The purchaser reserves the right to insist for witnessing the acceptance / Routine testing of the Bought out items.

The Bidders shall give 15 days advance intimation to enable the purchaser to depute his representative for witnessing the acceptance and routine tests. The inspection charges would be to the purchaser’s account

8. TEST REPORTS :

All test reports of tests conducted during manufacturing shall be maintained by the

supplier. These shall be produced for verification as and when requested for by the

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TECHNICAL SPECIFICATION FOR SUPPLY OF GALAVANISED M.S.BOLTS & NUTS OF ASSORTED SIZE

1. SCOPE The specification covers the manufacture, design, inspection, testing before dispatch, marking, packing and delivery at the consignees headquarter of M.S. Bolts & Nuts for 33 KV & 11 KV Sub-transmission line/sub-station, and operation & maintenance work.

2. STANDARDS The relevant Indian Standard Specification(latest amended) to which the material shall conform are as follows:-

S.No. Particulars For M.S. Bolts & Nuts

1 Grade Grade ”C” as specified in IS-1367(Part-2)/2002.

2 Dimension Nominal dia-16 mm length of bolt(IS-1363 Pt-I- 1992

40,100,250,300 mm Length of Nut-15 mm

(IS-1363-Part-III/1992 (with latest amendments)

3 Raw material Low or medium carbon steel.

4 Tolerance As per (IS:1367 Part-II)/

5 Chemical composition

For Bolt:IS:1367 Part(Pt.III/1991)

For Nut: IS:1367 (Pt.VI)/1980

6 Testing For Bolt:IS:1367 Part(Pt.III/1991)

For Nut: IS:1367 (Pt.VI /1980)

7 Sampling IS:2614-1969 for Bolts & Nuts

The M.S. Bolts & Nuts shall be purchased from the bidder who have valid ISI license. The bidder should furnish the copy of valid BIS License with the bid otherwise their offer shall be ignored.

3. FINANCIAL RESOURC ES AND EXPERIENCE

The bidder shall furnish the details regarding his previous experience in performing similar comparable work, the technical strength and manufacturing facilities available and also financial capability along with the tender. The bidder is also required to furnish the following information.

a. Standing of the firm as manufacturer/supplier b. Approximate qty., manufacture/supplied so far at his works on monthly basis.

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c. Testing facilities available at his works

4. WORKMANSHIP The characteristic and properties of finished product required are as detailed below:-

For Bolts & Nuts: (Properties class)

i) Properties class for bolts required. : 4.6 as specified in IS:1367-Part-II

ii) Properties class for nuts required : 5 as specified in IS:1367-Part-III/1980

CHEMICAL COMPOSITION

i) For Bolts: (IS-1367 Part-III) 1991

Carbon % max. 0.55

Phosphorous % 0.05

Sulphur % 0.06

ii) For Nuts:

Carbon % max. 0.50

Phosphorous % 0.12

Sulphur % 0.34 MECHANICAL PROPERTIES:

i) For Hexagonal Bolts:(IS-1367 Part-III)1991

a) Tensile strength(to be arranged on size 150 mm & above) : N/mm sq. 400 (min)

b) Stress under proof load. : N/mm sq. 225 (min)

c) Brinell Hardness : HB 114(min) to 238 max.

d) Rockwell hardness : HRB-Max. 67(min.) to 99.5 max.

e) Vickers harness : HV 120 (min) to 250 max.

f) Elongation after fracture : 3 Min. 22%

g) Strength under wedge loading

(to be arranged on size above 40 mm) : N/mm sq. 400 (min)

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h) Head soundness : No fracture

ii) For Hexagonal Nuts(IS:1367 Part-VI/1980 Table4)

a) Proof stress. : N/mm sq. 610 (min)

b) Vicker Hardness : HV-Min. 130 HV-Max. 302

5. ISI CERTIFICATION AND TYPE TEST CERTIFICATE The supplier must hold the licence of ISI mark. If supplier do not have ISI mark licence at the time of submission of tender documents, the same must be submitted before commencement of supplies, otherwise supplies shall not be accepted. Consequences on this account shall be to the suppliers account. .

The bidder shall furnish valid and authenticated type test certificates from a Govt. approved / Govt. Recognized / NABL Accredited laboratory / ILAC i.e. International Accreditation Corporation (in case of foreign laboratory) of similar rating and design of tendered material / equipment. Such type test certificates should not be older than 3 years as on the date of bid opening. For this purpose date of conducting type test will be considered.

The type test certificate by in house laboratory of bidding firms even if it is Govt. approved / Govt. Recognized / NABL Accredited laboratory / ILAC accredited, shall not be accepted, in case of their own bid. This will not apply if bidding firm is Govt. Company / Public sector undertaking.

The bidder should furnish documentary evidence in support of laboratory whose type test have been furnished, that the said laboratory is a Govt. / Govt. approved / Govt. Recognized / NABL Accredited laboratory / ILAC accredited (in case of foreign laboratory). The type test certificate shall be furnished either in original or copy duly attested by Notary.

TYPE TESTS The following tests shall constitute the type tests and shall be carried out as per relevant IS:1367 Part-III.

1) Chemical Composition Test 2) Test for Mechanical Properties for Hexagonal Bolts a) Tensile strength b) Yield stress c) Stress under proof load d) Brinell Hardness

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e) Rockwell Hardness f) Vickers Hardness g) Elongation after Fracture h) Strength under Wedge loading i) Head soundness 3) Test for Mechanical Properties for Hexagonal Nuts. a) Proof Stress b) Vickers Hardness ROUTINE/ACCEPTANCE TEST

The following tests shall be got conducted in presence of purchasers representative as per relevant IS:1367 Part-III/1991 with latest amendment for Bolts and IS:1367 Part-VI/1980 with latest amendment for Nuts on the samples taken from the offered lot material for the purpose of acceptance of that lot of material.

1) Chemical Composition Test. 2) Test for Mechanical properties for Hexagonal Bolts: a) Tensile strength b) Yield stress c) Stress under proof load d) Brinell Hardness e) Rockwell Hardness f) Vickers Hardness g) Elongation after Fracture h) Strength under wedgeloading i) Head soundness 3) Test for Mechanical Properties for Hexagonal Nuts: a) Proof stress b) Vickers Hardness 6. MARKING The bolts shall be marked with the following symbols on the top surface of the bolt head, either embossed or Indented, as given below:-

(a) The Manufacturer’s identification symbol (b) Property class (c) The material shall be marked as per the requirement of IS-1367 (Pt.XVIII)/ 1979 for

Bolts & Nuts. 7. PACKING AND FORWARDING The packing of material shall be made in two bags one HDP bag (inner) and one gunny bag (outer) or in double gunny bag, containing 50 Kg weight of Bolts & Nuts(Net wt.). The packing should capable to bear transportation hazards. The packing shall be such as to protect the material from the atmospheric effect like rains, humiity etc. The packing shall bear the marking as under:-

a) Certification regarding ISI b) Particulars of material(s) c) Quantity d) Manufacturer’s identification mark e) Complete dispatch details like name of the consignee and destination etc.

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8. TESTING OF MATERIAL AT CTL

The material received in stores shall be subject to test checking at CTL of Nigam before final acceptance of material. The procedure for the same shall be as under:-

(i) Sampling:- 5 samples out of 1 MT Nuts and Bolts of assorted size or part thereof from each inspected lot received in stores shall be selected for test checking of material and shall be got tested. The sample selection shall be done as soon as material is received in stores without the presence of representative of supplier. However testing of sample(s) at CTL shall be carried out in presence of representative of supplier after identification of sample by supplier’s representative.

(ii)Tests The following tests shall be carried out on the above items:- (a) Visual examination (b) Verification of dimension as per specification/ GTP/IS.

Testing shall be got done at the test laboratory of the Nigam i.e. CTL. For witnessing of the testing clear 7 days notice shall be given to the supplier stating date, time and place where the test is to be conducted. In case the supplier do not attend for witnessing the testing, the testing shall be proceeded and completed and action taken as per the contract.


The material received in the stores shall finally be accepted provided the selected samples passes the test in CTL. The sample(s) shall be subject to verification of dimension as per specification/GTP and will be accepted as per tolerances specified in specification/ relevant IS: The material will be accepted as per GTP/IS. The Executive Engineer (CTL) shall send copies of test reports to the purchaser, consignees and the supplier.

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TECHNICAL SPECIFICATION FOR SUPPLY OF GALVANISED M.S.ROD TYPE EARTHING SET WITH CLAMPS AND G.I. WIRE

1. SCOPE This specification covers design, manufacture, inspection and testing before dispatch,

supply and delivery at consignees headquarter of Galvanised M.S.Rod type earthing sets

with clamps and G.I. wire. The earthing sets shall be used to protect the 33 KV, 11 KV &

LT lines and sub-stations from faulty currents.

2. STANDARDS The relevant ISS: to which this material shall conform is indicated as below:-

For fabricated material

(i) Raw material test (Manufacturer’s Raw material test certificate as per ISS: 2062-

Grade ‘A’) (ii) Galvanisation test as per relevant IS:2633. (iii) Checking/verification of Dimension etc. as per approved drawing. (iv) Sampling for workmanship and dimension checking 3% of each lot and as per ISS-

4711-1976. For Galvanised steel wire:

(i) As per IS: 280(latest addition) (ii) Testing as per IS:7887 Grade-III

3. MARKING

Each bundle of earthing sets shall be legibly marked with the physical condition, weight, date of manufacture, trade mark or the name of manufacturer. The material which is inspected and cleared for dispatch shall be sealed with the JVVNL seal.

4. PACKING AND FORWARDING The Galvanised M.S.Rod type earthing sets shall be supplied in bundles (containing all items) and shall be suitably bound and fastened compactly and shall have a maximum weight of 400 Kgs. The bundles will be suitably protected by wrapping round by hession cloth/polythene cover to avoid damage in transit and corrosion

5. TEST CHECKING OF MATERIAL The material received in stores shall be subject to test checking in the test laboratory of Nigam (CTL) before final acceptance of material. The procedure for the same shall be as under:-

(i) One sample out of each sub-lot/lot of 2000 sets or part thereof from each inspected lot received in stores shall be selected for test checking of material and shall be got tested.

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The sample selection shall be done as soon as material is received in stores without the presence of representative of supplier. However testing of sample(s) at CTL shall be carried out in presence of representative of supplier after identification of sample by supplier’s representative.

(ii) Tests

The following tests shall be carried out on the selected samples at CTL .

(i) Visual examination (ii) Verification of dimension as per specification/ GTP/approved drawings. (iii) Galvanization uniformity test (iv) Weighment of selected sample


(A) ) Verification of dimension.

The sample(s) shall be subjected to verification of dimension check up as per specification/GTP/approved drawings and will be accepted as per tolerances specified in specification/ relevant IS: The material will be accepted to any extent if tolerances are in positive side. If tolerances are in negative side then the material shall be accepted to the extent as specified in IS, without any deduction. If the dimensions are in negative side beyond the specified tolerances in IS then it will be accepted to the extent double the negative side tolerance as specified in IS but with following deductions:-

(a) for M.S.Rod:- 2% of the cost of material

(b) Other parts :- 1% of the cost of material

If the dimensions are beyond double the permissible negative tolerance then material shall be rejected and the supplier shall replace at his own cost.

(B) Galvanization (Uniformity) test

(i) The sample shall be first tested for (n-2) number of dips where (n) is specified number of dips in the contract. If the sample(s) does not pass the uniformity of galvanization test for (n-2) dips, the material shall be rejected and the material relating to relevant lot/sub-lot to which sample(s) pertains shall have to be replaced by the supplier free of cost.

(ii) If the sample(s) has passed the uniformity of galvanization test for (n-2) dips, then it shall be tested for (n-1) dips. If the sample has not passed the uniformity of Galvanization Test with (n-1), then material pertaining to relevant lot/sub-lot shall be accepted with a deduction @ 10% of cost of material.

(iii) If the sample(s) has passed the uniformity of Galvanization Test with (n-1) dips, then sample shall be tested for last one dip of one minute to complete the test for ‘n’ dips. If the sample does not pass the uniformity test with specified number of dips i.e. ‘n’ dips, then material pertaining to relevant lot/sub-lot shall be accepted with a deduction @ 5% of cost of material.

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BILL OF MATERIAL

The bill of material for galvanized M.S.Rod type earthing set with clamps and wire as under:-

S.No. Particulars Unit Quantity

1 Galvanised M.S. Rod 20 mm dia electrodes having 3 Meter length

No. 1

2 Galvanised Earthing clamp of M.S.Flat of size 50x6 mm 220 mm length. One welded with earth electrode and loose to be bolted

Set (Two Pieces)

2

3 Galvanised Bolts, Nuts and Spring washers. No. 2

4 G.I.Wire Size 8 SWG of 15 Meter length No. 1

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TECHNICAL SPECIFICATION FOR SUPPLY OF HOT DIP GALVANISED STEEL STAY WIRE of 7/10 SWG

1. SCOPE This specification covers, manufacture, design, inspection ,testing before dispatch & delivery at consignees head quarter of following sizes of hot dip heavily galvanized stranded steel stay wire, complete in all respect as per GTP/ISS

i) Hot dip galvanized steel stay wire of 550-900 N/mm Quality confirming to IS- 2141/2000 in all respect Including chemical composition (Heavily coated Hard quality) of dia 7/3.15 mm(7/10 SWG)

2. STANDARDS

The finished material shall comply in all respect with the requirement of the latest edition of the relevant ISS as mentioned below:-

(i) The hot dip galvanized stranded steel stay wire (heavily coated) shall comply with the ISS:2141/2000, 4826/1979 and 6594/1977 with latest amendments thereof, if any in all respects, except herein otherwise stated, corresponding to grade-4 550-900 N/mm sq. minimum tensile strength quality. The galvanization coating of galvanized steel wire and technical supply conditions shall conform to IS:4826/1979 and IS:6594/1977 or latest amendment thereof if any.

(ii) Goods meeting other authoritative standards which ensure an equal or higher quality than the standards mentioned above will also be accepted.

(iii) The galvanized stranded steel stay wire shall be capable of withstanding the normal handling necessary for transportation and erection.

3. WORKMANSHIP:

The wire shall be manufactured from steel made by any suitable process(es) as mentioned in IS:2141/2000 & 7887/1975 and shall not contain sulphur and phosphorus exceeding 0.060 percent each.

Each coil shall be warranted to contain the joints only as permitted under relevant IS:2141/2000.

The galvanized stranded steel stay wire shall be well and clearly drawn to the dimension specified. The wire shall be free from scale, irregularities, imperfections, flaws splits and other defects and shall be uniformly galvanized having smooth and even zinc coating. The requirement for chemical composition of the wires shall conform to the value as specified in IS/7887/1975 and IS:280/1978.

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4. ISI CERTIFICATION The supplier must hold the licence of ISI mark. If supplier do not have ISI mark licence at the time of submission of tender documents, the same must be submitted by the bidder up to the official working hours of one working day prior to the schedule / notified date of opening of price bid.

(A) TEST BEFORE DESPATCH: The stay wire shall be subject to the following tests as per ISS at manufacturer’s works before dispatch,.

ROUTINE/ACCEPTANCE TEST:- The following tests on selected samples as per relevant standard shall be got conducted in presence of purchaser’s representative.

i) Tensile and Elongation test ii) Adhesion and wrap test iii) Zinc uniformity and coating test iv) Chemical analysis test v) Dimension and weighment checkup of sample coils. vi) Lay ratio (B) SAMPLING PLAN:

As per the provisions of IS:2141/2000.

(C) TOLERANCE ON TEST RESULTS

i) Weight of the coil – 40-60 Kg per coil. ii) Dia of wire ±2.5% of wire dia with a minimum of 0.025 mm iii) Lay length -12 to 18 times strand dia iv) Tensile and elongation test –As prescribed in IS:2141/2000. v) Zinc uniformity and coating test – As per IS:4826 vi) Chemical composition test IS:7887 5. MARKING

Each coil of wire shall be legibly marked with the physical condition, size of wire, weight, date of manufacture trade mark or the name of manufacturer. The material which is inspected and cleared for dispatch shall be sealed with the Nigam’s seal.

6. PACKING AND FORWARDING: The galvanized steel stay wire shall be supplied in coils. Each coil of GSS wire shall have single continuous length and shall be suitably bound and fastened compactly and shall weigh 40 kgs to 60 kgs. The coils will be suitably protected by wrapping round by hession cloth/polythene cover to avoid damage in transit and corrosion. Each coil shall be marked as mentioned above.

7. TYPE TEST / CHECKING OF MATERIAL AT STORES The material received in the stores shall be subject to test checking at CTL of Nigam before final acceptance of the material. The procedure for the CTL test shall be as under :

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SAMPLING One sample out of each lot/sub-lot of 400 Nos coils or part thereof from each inspected lot received in stores shall be selected subject to maximum 7 samples for test checking of material and shall be got tested at the CTL of JVVNL. The sample selection shall be done in the presence of supplier or his authorized representative for which advance notice shall be given to the supplier.

TESTS AT CTL

The following tests shall be carried out on the selected samples of G.S.Stay wire as per relevant standards:-

(a) Uniformity of galvanization test (b) Tensile test (c) Dimensional check

For witness the test, advance notice to the supplier shall be given by CTL, stating date, time. In case the supplier do not attend for witnessing the testing, the testing shall be proceeded and completed and action shall be taken as per the contract.

The test reports shall be furnished to the purchaser, consignee and supplier.

8. CRITERIA FOR ACCEPTANCE OF ABOVE TEST

The inspected material should be strictly in accordance to the relevant ISS / GTP of the specification, however, the material shall be accepted on the basis of test results found/observed during test at CTL as mentioned below.

(a) For uniformity of galvanization test.

(i) The sample shall be first tested for (n-1) number of dips where n is specified No. of dips of one minute in the contract. If the sample does not pass the uniformity of galvanization test for (n-1) dips, the material shall be rejected and the relevant lot/sub-lot to which the sample pertains shall have to be replaced by the supplier free of cost.

(ii) If the material has passed the uniformity of galvanization test for (n-1) dips then it shall be tested for last one dip of one minutes to complete the test for ‘n’ dips. If the sample does not pass the uniformity of Galvanisation Test with ‘n’ then material pertaining to relevant lot/sub-lot shall be accepted with a deduction @ 5% of cost of material

(iii) If the sample(s) have passed the Test with number of dips as specified in the contract (n) , then material pertaining to relevant lot/sub-lot shall be accepted.

b) Tensile test:-If the material fails in tensile test the same shall stands rejected. c) Dimensional check:- If the material fails in dimensional check the same shall stands

rejected.

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TECHNICAL SPECIFIICATION FOR SUPPLY OF G.S WIRE SIZE 6 SWG AND 8 SWG

1. SCOPE

This specification covers design, manufacture, inspection ,testing before dispatch & delivery at consignees headquarter of following sizes of hot dip heavily galvanized steel wire, complete in all respect as per GTP/ISS

Hot dip galvanized steel wire of 550-900 N/mm

(i) Quality confirming to IS-280/1978(latest amended) in all respect including chemical composition (Heavily coated Hard quality) of dia 4 mm

ii) Hot dip galvanized steel wire of 550-900 N/mm Quality confirming to IS-280/1978(latest amended) in all respect including chemical composition (Heavily coated Hard quality) of dia 5 mm

2. STANDARDS

i) The hot dip galvanized steel wire (heavily coated) shall comply with the ISS:280/1978, with latest amendments thereof, if any, corresponding to grade-4, 550-900 N/mm sq. minimum tensile strength quality in all respects, except herein otherwise stated.

ii) The galvanization coating of galvanized steel wire and technical supply conditions shall conform to IS: 4826/1979 and IS:6594/1977 or latest amendment thereof if any.

iii) Goods meeting other authoritative standards which ensure an equal or higher quality than the standards mentioned above will also be accepted.

iv) The galvanized stranded steel wire shall be capable of withstanding the normal handling necessary for transportation and erection.

3. ISI CERTIFICATION AND TYPE TEST CERTIFICATE

The supplier must hold the licence of ISI mark. If supplier do not have ISI mark licence at the time of submission of tender documents, the same must be submitted by the bidder up to the official working hours of one working day prior to the schedule / notified date of opening of price bid.

(A) TEST BEFORE DESPATCH: The G.S wire shall be subject to the following tests as per ISS at manufacturer’s works before dispatch,.

ROUTINE TEST/ACCEPTANCE:- The following tests as per relevant standard shall be got conducted in presence of purchaser’s representative.

(i) Tensile and Elongation test (ii) Adhesion and wrap test

(iii) Zinc uniformity and coating test (iv) Chemical analysis test (v) Dimension and weighment checkup of sample coils. (vi) Lay ratio

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(B) SAMPLING PLAN: As per the provisions of IS:280/1978.

(C) TOLERANCE ON TEST RESULTS as per IS:280/1978

(i) Weight of the coil – 40-60 Kg per coil. (ii) Dia of wire (iii) Lay length, wrap test (iv) Tensile and elongation test (v) Zinc uniformity and coating test (vi) Chemical composition test

4. MARKING


5. PACKING AND FORWARDING: The galvanized steel wire shall be supplied in coils. Each coil of GS wire shall have single continuous length and shall be suitably bound and fastened compactly and shall weigh 40 kgs to 60 kgs. The coils will be suitably protected by wrapping round by hession cloth/polythene cover to avoid damage in transit and corrosion. Each coil shall be marked as mentioned above.

6. TYPE TEST / CHECKING OF MATERIAL The material received in the stores shall be subject to test checking at CTL of Nigam before final acceptance of the material. The procedure for the CTL test shall be as under :

SAMPLING

One sample out of each lot/sub-lot of 400 Nos coils or part thereof from each inspected lot received in stores shall be selected subject to maximum 7 samples for test checking of material and shall be got tested at the CTL of JVVNL. The sample selection shall be done in the presence of supplier or his authorized representative for which advance notice shall be given to the supplier.

TESTS AT CTL

The following tests shall be carried out on the selected samples of G.S. wire as per relevant standards:-


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TECHNICAL SPECIFICATION OF 11 KV CTPT METERING SETS

3.1 SCOPE: This specification covers the design, manufacture, assembly, testing and delivery of three phase four wire 11 KV/ 110V oil cooled outdoor type combined CTPT units for feeder metering & Indoor type combined CT-PT unit for consumer metering purpose having 1 No. Three phase potential transformer and 3 Nos. single phase paper impregnated oil emersed current transformers for different phases in common tank equipped with weather proof bushing for outdoor use as per technical data in corporatedin this specification. 3.2 APPLICABLE STANDARDS: Unless otherwise modified in this specification, 11 KV CTPT Metering Sets shall comply with the following Indian Standard Specification (latest version): IS:2705-1992 Specification for current transformers. IS:3156-1992 Specification for voltage transformers. IS:5621-1980 Specification for Insulators/Bushing IS:2099-1986 Specification for insulators/ bushing IS:3347-1986 Specification for Insulators/bushing IS:335-1983 Specification for new insulating oil IS : 5561 Specification for terminal connectors. Equipments conforming to any other international standard(s) which ensure(s)equal or better quality than the standard(s) mentioned above will also be acceptable andin such case(s) the copy of standards (English version) adopted should be provided. 3.0311 KV CTPT Metering Sets: A) 11 KV Single Phase Current Transformer (3 Nos. for R Y & B phases).The 11 KV

current Transformer shall be paper impregnate oil immersed type, single phase 50 HZ confirming to IS:2705/1992 with latest amendment in all respect except where ever modified in this specification.

The 11 KV current Transformer shall have the following technical characteristics/ parameters. Sr.NoParticulars Parameters i) Normal system voltage (KV rms) 11 ii) Highest system voltage (KV rms) 12 iii) Frequency 50 Hz iv) Impulse withstand voltage 95 KV (Peak) v) i) One minute power frequency dry withstand voltage (on assembled CTPTset) a) primary (KV r.m.s.) b) secondary (KV r.m.s.) ii) One minute frequency wet withstand voltage (KV Peak) (On assembled CT-PT ) 28 3 Root 2x28 Rms vi) Transformation ratio (CT Ratio) a) For Consumer Metering b) For Feeder Metering 100/5 A, 50/5 A & 15/5 A 200/5 A vii) Rated output (VA burden) 10 VA

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viii) Class of accuracy 0.5S ix) Rated continuous thermal current 1.2 times of rated primar current x) Short time thermal current rating6.4 KA for one second for CT ratio 15/5 A, 18 KA for one second for CT Ratio 50/5 A &100/5 A18 KA for 3 seconds for CT ratio 200/5 A xi) Rated dynamic current 2.5 times of short time thermal current rating. xii) Number of cores One xii) Instrument security factor Not exceeding 5 xiii) Max. ratio error As per IS:2705/1992 xiv) Max. phase angle error As per IS:2705/1992 xv) Max. temp. rise over max. ambient temp. of 50 deg. C at rated continuous thermal current at rated frequency and with rated burden. As per IS:2705/1992

B) 11 KV Voltage Transformer: 11 KV voltage Transformer will be used along with CTs of description stated above. This shall be paper impregnate oil immersed type conforming in all respect to the Indian Standards specification IS:3156/1992 with latest amendment except where modified in this specification. The 11 KV voltage transformer shall have the following ratings/ technical parameters: Sr.No . Particulars Parameters i) Nominal system voltage (KV rms) 11 Ii) Highest system voltage (KV rms) 12 Iii) Nos. of phases Three iv) Impulse withstand voltage (KVP) (on assembled CTPT set) 95 v) a) One minute power frequency dry withstand voltage (on assembled CT-PT set) i) primary (KV r.m.s.) ii) secondary (KV r.m.s.) b) One minute frequency wet withstand voltage (KV Peak) (On assembled CT-PT set) 28 3 Root 2x28rms vi) Frequency 50 Hz vii) Transformation ratio (PT Ratio) 11 KV/ 110V viii) Rated output (VA burden) 30 VA per phase ix) Class of accuracy 0.5 (As per IS:3156/1992) x) Winding connection Star/Star with HT neutral earthed. xi) Rated voltage factor and time 1.2 continuous and 1.9for 30 seconds. xii) Temp. rise over max. ambient temp.Within limits ofIS:3156/1992 xiii) Max. Phase angle error Within limits ofIS:3156/1992 xiv) Ratio error (Max.) Within limits ofIS:3156/1992

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3.4 GENERAL TECHNICAL DESCRIPTION OF 11 KV CT-PT METERING SETS: i) The CT PT Metering set shall comply to the latest standards mentioned in the

specification and guaranteed technical particulars. ii) High voltage winding of 11 KV instrument transformers shall have paper insulation

impregnated with oil under vacuum. The paper used for insulation shall be of high insulation grade. The process of impregnation shall be detailed out in the tender.

iii) The core material of CT-PT sets shall be of high grade, non-ageing, electrical silicon steel having low hysteresis loss and high permeability to ensure accuracy at both normal and over current/ voltage.

iv) The instrument transformers shall be contained in a fully weather proof, outdoor type, platform mounting and also suitable for pole mounting type tank with 6 Nos. of 12 KV class weather proof bushing for incoming and outgoing connections.

v) The thickness of MS sheet used for fabrication of tank shall be minimum 3.15 MM for sides and bottom and 5 MM for top cover .

vi) The 11 KV CT-PT set should have compact construction and the general arrangement Dimensional drawing, mounting arrangement shall be got approved before commencement of supplies.

vii) The external surfaces of tanks of CT-PT sets shall be painted with one coat of primer and two coats of synthetic enamel paint of shade No.631 of IS:5. The internal surfaces of the tank shall be painted with two coats of a suitable heat resistant oil insoluble paint.

viii) The metering sets shall be supplied with first filling of insulating oil conforming to IS:335 (with latest amendment).

ix) The bushings used in the CT-PT sets shall confirm to IS:2099, IS:5621 and IS:3347 (latest amendments). These shall be suitable for operation in heavily polluted atmosphere with creepage distance of 25 MM/KV.

x) The minimum clearance between phases and phase to earth as specified in the relevant ISS should be maintained.

xi) The paper impregnated oil immersed type instrument transformers shall be complete with all fittings and accessories mentioned at Clause No. 3.06 of this specification.

xii) The 11 KV CT-PT sets shall be hermetically sealed type (should not communicate with atmospheric air) in construction without any oil conservator. The quality and work-man-ship shall be of high standard.

xiii) For load shedding single phasing is adopted in the 11 KV system. The offered 11 KV CT-PT set shall be suitable for working under such abnormal operation condition.

xiv) CT-PT sets shall be used for 3 phase 4 wire KWH metering. As such 11 KV CT PT sets shall have 3 Nos. CTs.

xv) The 11 KV CT PT sets shall have one No. of Three Phase Potential Transformer. The primary winding of single phase PT shall be connected in star formation in the tank with common external neutral.

xvi) The neutral of primary PT winding shall be floating. The neutral of PT Secondary winding shall be earthed.

xvii) The secondary winding neutral of PT and secondary terminals of CTs and PTs shall be brought out in one single secondary terminal box through 3 KV bushings. The terminals shall be marked as per ISS and supporting marking

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plate with earth terminal shall be provided. The secondary terminal box compartment shall be divided in two portions - One portion containing secondary of all CTs and the other portion shall contain all secondary PT connections with neutral and one body earthed. The whole compartment shall be covered by one bolted cover with sealing arrangement. At least two bolts at diagonally opposite corners of secondary terminal box shall be suitable for sealing arrangement. All other bolted covers and inspection windows covers, where provided shall also have sealing bolts for sealing purpose. Suitably shorting links shall be provided for individual CT shorting and PT secondary neutral.

xviii) The secondary terminal box shall have cable gland/ flange suitable to receive two Nos. control cable of size 6 core X 4 sq.mm. and 4 core x 2.5 sq. mm at the bottom of the secondary box for metering connections to secondary winding of 11 KV CT-PT circuits respectively.

xix) The 11 KV CT PT Set shall have 3 Nos. incoming and 3 Nos. outgoing outdoor type bushing. The 11 KV CT-PT Sets shall have 6 Nos. bimetallic terminal connectors suitable for Dog Conductor for ratio 200/5 Amp. These should be type tested from CPRI/ NABL accredited Labs. These test reports should not be older than 5 years for Short Circuit Test. The dimension & drawing shall be furnished along with tender duly signed and sealed by testing authority. Inspecting officer shall verify the original type test reports at the time of inspection for terminal connectors & bushings.

xx) No oil drain plug at the bottom of the CT-PT Sets be provided. xxi) Embossing/ punching with minimum height of 10mm of Sr. No., ratio & TN No.

be done on the tank of the CT-PT Sets. xxii) Manufacturer’s name in short should be embossed/ punched. xxiii) CT Ratio should be painted on tank body so that it should be visible clearly. xxiv) The under base of CT-PT Sets of 11 KV shall be provided with 2 Nos.75x40x6mm

channels as shown in the figures detailed in Annexure –I to make them suitable for fixing to a plate form or plinth. These channels shall be provided through continuous welding with tank of the CT-PT Sets.

xxv) For feeder metering CT-PT sets i.e. rating of 200/5 A Amp. HV Metal parts (Primary terminal) shall be of 20 mm dia and made of copper. The primary terminal shall be along the entire length of bushing. However brass may be used for consumer metering CT-PT sets for which HV Metal parts (Primary terminal) shall be of 16 mm dia.

xxvi) The equipment shall be suitable to withstand for loading conditions when supply for one phase is disconnected from primary side. xxvii) Bushing rod of 20 mm dia made of copper shall be used for 11KV CT-PT Sets for feeder metering.

xxviii) 2 Nos., 5/8” dia, 3” length earthing bolts with 2 nuts, 2 flat & 2 Nos. Spring washers shall be provided with each CT-PT Set.

xxx) Spring loaded pressure release device shall be provided on each 11KV CT-PT Set for releasing of accumulated gases.

xxx) The CT-PT Set (for outdoor installation) top shall be taper / slanting with minimum slant of 10 mm.

xxxi) The following sealing arrangement for providing seals on each 33 KV CT-PT sets hall be made by the manufacturer.

i) 4 Nos. holes of 2.5 mm dia on each bushing clamp bolts of 6 nos. HT bushings for providing two polycarbonate seals at diagonally opposite bolts

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of each bushing clamp in M&P lab after successful testing as required. ii) 4 Nos. holes of 2.5 mm dia on the bolts provided at four corners of top

cover for providing two polycarbonate seals at diagonally opposite corner of CT-PT set by the inspecting officer after successful testing and providing polycarbonate seals in M&P lab after successful testing as required.

iii) 4 nos. sealing holes on the name plate (R&D plate so that our inspecting officer may provide numbered seal on one side of the plate covering top & bottom holes whereas on the remaining two holes of other side, the one numbered seal will be provided by MT Lab after successful testing.

3.5 FITTING AND ACCESSORIES: The outdoor platform/ pole mounting type metering equipments shall be complete with tank, fittings and accessories as detailed below: 1 No. Electrically welded sheet steel tank/ enclosure for accommodating above instrument transformers with suitable bolted cover. 6 Nos. Outdoor single terminal porcelain bushing of reputed make without arcing horns. 3Nos. for incoming and 3 Nos. for outgoing. 1 No. Secondary terminal box. The terminal box opening door/cover shall have suitable sealing arrangement. The necessary gland/ socket shall be in the scope of supply. 1 No. Oil filling hole with cap/plug. 1 No. Toughened prismatic oil level indicator with min. oil level marking. 2 No. Lifting lugs for lifting the complete CT-PT unit. 2 Nos. Earthing terminals. 1 Set Under base channels with suitable fixing holes for mounting on plat-form/poles. 1 Set Detachable coller assembly. 1 No. Rating and diagram plate. 6 Nos. Bimetallic Terminal Connectors. [For each 11 KV CT-PT Set of ratio 200/5 Amp.] 3.06BUSHING: The bushing shall confirm to IS:5621-1980 and IS:2099-1986 and its subsequent amendment, if any, the bushing shall be of standard make. The make and catalogue No.of bushing shall be clearly stated in the guaranteed technical particulars. The type tests certificates of bushings not older than five years shall also be furnished along with tenders. The bushing rods and nuts shall be made of material as per cl.3.05 (xxv).The dimensions of 12 KV class bushings and their related parts shall conform to the relevant Indian Standards as detailed below: Voltage class Indian Standard 12 KV bushing For porcelain parts IS:3347 (Part-III) Sec.I-1972 or the latest version thereof For metal parts IS:3347 (Part-III) Sec.II-1967). The minimum electrical clearance of 255 mm between phases shall be obtained with the bushings mounted and phase to earth clearance should be maintained as specified in relevant IS/ Indian Electricity rules. On the bushings clamp bolt of CT-PT Sets two holes on two bolts of size 2.5mm (total 12 holes on 12 bolts) at diagonally opposite sides be provided to enable metering wing to seal these bolts after successful testing in Meter Labs.

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3.7 GUARANTEED TECHNICAL PARTICULARS, DRAWINGS AND QUALITY ASSURANCE PLAN: The tenderer shall furnish the guaranteed technical particulars along with the detailed general arrangement dimensional drawings mounting arrangements, connection diagrams and quality assurance plan etc. with the tender. Particulars which are subject to guarantee shall be clearly marked in GTP 3.8 INSTRUCTION MANUALS: The successful tenders shall have to supply required number of operation and maintenance instruction manuals along with the requisite sets of approved drawings of the equipments covered under this specification. One set of above manuals and drawings shall also be sent along with the delivery of 11 KV CT PT unit to the consignee. 3.9 INSPECTION, TESTING AND CHECKING: 3.9.1 In the event of order, the supplier shall have to get type tests conducted as

per requirement of relevant standards/ specification on one sample of lowest ratio out of first offered lot for inspection comprising of minimum 25% of ordered quantity of lowest ratio in presence of JVVNL inspecting officer without any extra cost. The Impulse test shall be carried out on all the three phases and short circuit test on any one phase selected by the witnessing officer. For this supplier shall make arrangement for type testing to be got conducted from any NABL accredited laboratory and arrange transportation of sample selected from first offered lot for inspection to testing lab & from testing lab to supplier’s works. The supplier shall offer the type tested CT-PT set after its re-assembling in subsequent lot. The supplies shall only be accepted & payment against supplies shall be released only after receipt of successful type testing for all type tests on sample.

3.9.2 Routine tests as per relevant standard along with accuracy test of CT as perIS:2705 (Pt-II)-1992 and that of PT IS:3156 (Pt.II)-1992 shall be carried out on each equipment covered by this specification in the presence of purchaser’s representative. All test reports shall be submitted and got approved from the purchaser before dispatch of the equipment.

3.9.3 The supplier shall simulate single phase condition in their laboratory for testing one 11 KV CT-PT set of any ratio from each lot offered for inspection under such condition for 24 hours. The errors of PT shall be measured before and after application of single phasing condition for at least 24 hours and results shall be within permissible limits of specified accuracy class. This test shall be done as acceptance test.

3.9.4 One CT-PT set of each ratio in each offered lot should be subjected to temperature rise test .The test shall be carried out simultaneously application of rated current (1.2 lb) and rated voltage (12 KV) and also ISF test, at firm’s works free of cost.

3.9.5 During routine/ acceptance test, errors for CTs shall be conducted at 1 %, 5%,20%, 100% and 120% of rated current and in case of PT at 80%, 100% and120% of rated voltage.

3.9.6 Algebraic summation of errors of standard CTs/PTs to the errors observed

on CTs/PTs under test should be made to get final errors on specified percentage current/ voltage/ burden. If class of accuracy of standard CT-PT is less than 10times of the accuracy of CT-PT set under test.

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3.9.7 Leak test :- One CT-PT set of each rating in each offered lot should be subject edto ‘Leak Test’ through Nitrogen gas for a pressure of 10 PSI (Pound sq. inch) for half an hour and pressure shall not drop more than 2 PSI. There should be no leakage observed at any part of CT-PT set.

3.9.8 One CT-PT set of each rating in each offered lot shall be opened for verifying the diameter and cross sectional area of primary coil conductors including verification of GTP. The verification of diameter & cross sectional area of primary coil conductor of the CT-PT Set shall be verified for any ratio at stores also. If CT-PT set fails in above verification at stores, entire lot shall be rejected and the supplier shall lift the rejected lot. In case it founds within specific limits, the supplier at his own cost shall reassemble/replace the physically opened CT-PT set at works/stores.

3.9.9 One sample of oil shall be selected for each ratio and shall be tested for Breakdown voltage b) Tan delta at 90 Deg.C.The oil supplied with CT PT set shall be of EHV grade Transformer oil suitable for insulation and coding of the electric transformers of extra high voltage and shall conform to IS 335 (with latest amendments)If CT-PT set fails in any of the above tests/verification at works , entire lot shall be rejected.

3.9.10 during the inspection at firm’s works, inspecting officer / agency shall provide polycarbonate seals on each CT-PT set as under -

i) One polycarbonate seal on one side of the plate covering top & bottom holes.

ii) Two polycarbonate seal at diagonally opposite corner of top cover of CT-PT set.

3.10 TYPE TEST: 3.10.1 Certified copies of all type tests as per IS-2705-1992, IS:3156-1992 with

latest amendments listed below obtained from any accredited CPRI/NABL accredited test laboratory on similar equipments included in this specification shall be furnished) i) Short Time Current Test.

ii) Lightening Impulse voltage withstand Test. iii) Temperature Rise Test. iv) Wet Pow er Frequency Voltage Withstand Test. v) Determination of Errors according to the requirement of the appropriate Accuracy Class. - vi) Instrument Security Factor Test.

3.10.2 The bidder shall submit all Type Test reports for lowest ratio of offered CTPT sets along with tender

3.10.3 Bidder shall furnish the calculations of short time thermal current of all ratios of offered CT PT sets, on the basis of cross-sectional area of primary conductor of Type tested CT PT set.

3.10.4 The purchaser shall have right to get conducted type test during currency of

the contract on the sets received in the Stores at purchaser’s cost. In case of failure in type tests, following provisions shall be applicable: -

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3.11 NAME PLATE AND MARKING: a) The equipment shall have a non detachable type name plate which should be

clearly visible and effectively secured against removal having markings as per requirement of IS. In addition, Sr .No., Ratio and date of dispatch shall have to been graved on bushing side of tank with letters of suitable depth & 25 mm height filled with red colour.

b) The- main and load are to be stenciled on top cover on main and load side respectively.

3.12 MAINTENANCE AND GUARANTEE: Performance guarantee of the equipment shall be for the period of 36 months from the date of receipt in stores. The month & year of expiry of guarantee period shall be marked on the name plate. Equipment failed within such guarantee period shall have to be re4placed /repaired free of cost within 45 days of intimation. Bidder shall furnish successful routine test reports of the equipment. If purchaser desires inspection prior tom dispatch, an inspecting officer shall be nominated for verification for the test reports. Failed equipment (s) shall only be lifted after receipt of replacement for the same. Transportation for lifting

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Technical Specification of Solar Panels :- Scope of work and Technical Specifications 1.1 Introduction In grid-connected Solar Photo-Voltaic (SPV) systems, solar energy is fed in to the building loads that are connected to the public electricity grid through a service connection with surplus energy being fed into the grid and shortfall being drawn from the grid. Production of surplus energy may happen when solar energy produced exceeds building load energy demand. This surplus is fed into the grid. During the night/holidays or when during the day energy demand in the building exceeds solar energy production, energy is drawn from the grid. Grid connected solar PV systems have no battery storage and will not work during grid failure. For buildings with grid connected solar PV systems, the service connection meter needs to be of the bidirectional type, whereby import kWh and export kWh are separately recorded. A grid-connected Solar Photo Voltaic (SPV) power plant consists of SPV array, Module Mounting Structure, Solar Grid Inverter (SGI), control and protection devices, circuit breakers, interconnection cables and switches. Components and parts used in the SPV power plants shall conform to the BIS or IEC or other international specifications, wherever such specifications are available and applicable. 1.2 Quality and Workmanship Solar PV modules are designed to last 25 years or more. It is therefore essential that all system components and parts, including the mounting structures, cables, junction boxes, distribution boxes and other parts also have a life cycle of atleast 25 years. Therefore all works shall be undertaken with the highest levels of quality and workmanship. During departmental inspection and its representatives will pay special attention to neatness of work execution and conformity with quality and safety norms. Non compliant works will have to be redone at the cost of the Installer. 1.3. Solar Photo Voltaic Module Type: Multi Crystalline Solar Module No. of modules: 80 Peak Power (Pmax) : >250 Wp Max Power Current (Imp): >8 Amp No. of Cells: 60/72 Max Power Voltage (Vmp): Should not be less than 30 V/36 V Tolerance 0, +3%( positive tolerance only) Module Efficiency (%) : >15 Weight <20Kgs Glass High tempered Anti-reflective glass Frame Anodized aluminum alloy Junction Box IP65, TUV-UL certified Blocking diodes: Schottky type Each PV module must use a RF identification tag (RFID), which must Contain the following information: (i) Name of the manufacturer of PV Module (ii) Name of the Manufacturer of Solar cells (iii) Month and year of the manufacture (separately for solar cells and module) (iv) Country of origin (separately for solar cells and module) (v) I-V curve for the module (vi) Peak Wattage, Im, Vm and FF for the module (vii) Unique Serial No and Model No of the module (viii) Date and year of obtaining IEC PV module qualification certificate (ix) Name of the test lab issuing IEC certificate

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(x) ) Other relevant information on traceability of solar cells and module as per ISO 9000 series PV modules used in solar power plants/ systems must be warranted for their output peak watt capacity, which should not be less than 90% at the end of 10 years and 80% at the end of 25 years Make: Any MNRE approved. 1.4 Module mounting structure Structure shall support SPV modules at given orientation absorb and transfer the mechanical loads to the roof uniformly. The structure should be designed to withstand the wind speed of 150 KMPH. The Module Mounting structure shall be made up of Hot dipped galvanized material. The minimum thickness of galvanization shall be at least 120 microns. All nuts & bolts shall be made of very good quality stainless steel. The minimum clearance of the lowest part of the module structure and the developed ground level shall not be less than 500 mm. Leg assembly of module mounting structure made of different diameter galvanized structure are accepted. The work should be completed with supply, fitting fixing of clamps, saddles, nut & bolts etc. The structure shall be designed to allow easy replacement of any module and shall be in line with site requirements. There shall be no requirement of welding or complex machinery at site. The manufacturer shall specify installation details of the PV modules and the support structures with appropriate diagrams and drawings. 1.5 PCC Array Foundation Base:- The legs of the structures made with GI angles will be fixed and grouted in the PCC foundation columns made with 1:2:4 cement concrete. The bidder can visit the site before quoting the rate for civil works. After taking in to consideration all aspects of the site, the bidder shall quote for works. No extra claim shall be entertained at post project stage. The foundation design of module structure shall be submitted to engineer in charge for approval. The work will be carried out as per designs approved by Engineer in Charge. Incase of any defects arising in the building during guarantee period of Two years, the contractor shall rectify the same at their own cost. 1.6 Solar Array Fuse :- The cables from the array strings to the solar grid inverters shall be provided with DC fuse protection. Fuses shall have a voltage rating of 1,000V DC, current rating as required and shall have DIN rail mountable fuse holders and shall be housed in thermoplastic IP 65 enclosures with transparent covers 1.7 DC Distribution Box A DC distribution box shall be mounted close to the solar grid inverter. The DC distribution box shall be of the thermo plastic IP65 DIN rail mounting type and shall comprise the following components and cable terminations: – Incoming 2 core (Positive and negative DC) cables from the DC Combiner Box; – DC circuit breaker, 2 poles (the cable from the DC Combiner Box will be connected to this circuit breaker on the incoming side); – DC surge protection device (SPD), class 2 as per IEC 60364-5-53; – Outgoing 2 core cable (Positive and negative DC) to the solar grid inverter. As an alternative to the DC circuit breaker a DC isolator may be used inside the DC Distribution Box or in a separate external thermoplastic IP 65 enclosure adjacent to the DC Distribution Box. If a DC isolator is used instead of a DC circuit breaker, a DC fuse shall be installed inside the DC Distribution Box to protect the DC cable that runs from the DC Distribution Box to the Solar Grid Inverter.

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1.8. Power Conditioning Unit – Inverter: Technical Specification of inverter Rated AC power 10 KW Phase 3 Nominal AC Volts 415 V Frequency HZ 50 Higher efficiency, more than 97% Voltage Range AC 320-460 Harmonics below 3% Max AC current 3 X 29.2 Internal Consumption at night < 0.5 W Max DC current 41 A DC Isolator required Nominal PV Power (kW) 10 Grid Specification 3ɸ415v, 50Hz, 4 wire Grid tolerance 10%,-15%, ±3Hz Power Factor >0.99 MPPT operating range-DC Within 400 to 900 V Max PV array volts VDC 1000 Max operating Temp Up to 55Deg C Power Conditioning Unit must confirm relevant IEC standards: IEC 62040/IEC 61683/IS 61683 and IEC 60068 -2(1,2,14,30) Protection degree:- IP 65 for outdoor mounting, IP 54 for indoor mounting Description Values Information Type of Inverter Inverter Model 10 K Control Range 0-100% Control Resolution 1% Hysteresis in control scheme for forward power 2% Data Logging Interval 10 Minute (ii) Type of Interface Ethernet RJ45 and RS485/RS 232 Cooling convection Display type:- LCD for data display. LCD/LED for status display. Display parameters to include Output power (W), cumulative energy (Wh), DC voltage (V), DC current (A), AC Voltage (V), AC frequency (Hz), AC Current (A); cumulative hours of operation. Grid Parameters Grid (R,Y,B) (V, I, PF) Inverter Parameters Power %, Power Make:-Any MNRE approved. 1.9 AC Distribution Box An AC distribution box shall be mounted close to the solar grid inverter. The AC distribution box shall be of the thermo plastic IP65 DIN rail mounting type and shall comprise the following components and cable terminations: – Incoming 5 core cable from the solar grid inverter – AC circuit breaker, 4 pole – AC surge protection device (SPD), class 2 as per IEC 60364-5-53 – Outgoing cable to the building electrical distribution board. 1.10 Connection to Building Electrical System A. The AC output of the solar grid inverter shall be connected to the building’s electrical system after the DISCOM service connection meter and main switch load side. The solar grid inverter output shall be connected to a dedicated module in the Main Distribution Board (MDB) of the building. It shall not be connected to a nearby load or socket point of the building.

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B. For buildings or loads with diesel generator backup, the wiring of the solar grid inverter shall be such that the solar grid inverter cannot run in parallel with the diesel generator. This implies that the solar grid inverter must be connected to a distribution board on the grid side of the automatic or manual change-over switch or as per the requirement of DISCOM. 1.11 Cables All cables shall be supplied conforming to IEC 60227/ IS 694 & IEC60502/ IS 1554 Voltage rating: 1,100V AC, 1,500V DC. For the DC cabling, XLPE insulated and PVC sheathed, UV stabilized single core flexible copper cables shall be used. Multi-core cables shall not be used. or the AC cabling, PVC or XLPE insulated and PVC sheathed single or multi-core flexible copper cables shall be used. Outdoor AC -plastic clamps at intervals not exceeding 50 cm. The minimum DC cable size shall cables shall have a UV-stabilized outer sheath. The total voltage drop on the cable segments from the solar PV modules to the solar grid inverter shall not exceed 2.0%. The total voltage drop on the cable segments from the solar grid inverter to the building distribution board shall not exceed 2.0% The DC cables from the SPV module array shall run through a UV stabilized PVC conduit pipe of adequate diameter with a minimum wall thickness of 1.5mm. Cables and wires used for the interconnection of solar PV modules shall be provided with solar PV connectors and couplers. All cables and conduit pipes shall be clamped to the rooftop, walls and ceilings with thermobe 4.0 mm or above copper as per load requirement. The minimum AC cable size shall be Aluminum as per load requirement. In three phase systems, the size of the neutral wire size shall be equal to the size of the phase wires. The following colour coding shall be used for cable wires: – DC positive: red (the outer PVC sheath can be black with a red line marking) – DC negative: black – AC three phase: Phases: red, yellow, blue; neutral: black – Earth wires: green Cables and conduits that have to pass through walls or ceilings shall be taken through a PVC pipe sleeve. Cable conductors shall be terminated with tinned copper end-ferrules to prevent fraying and breaking of individual wire strands. The termination of the DC and AC cables at the Solar Grid Inverter shall be done as per instructions of the manufacturer, which in most cases will include the use of special connectors.

1.12 Earthing The PV module structure components shall be electrically interconnected and shall be grounded. Earthing shall be done in accordance with IS 3043-1986, provided that earthing conductors shall have a minimum size of 6.0 mm2 copper, 10 mm2aluminum or 70 mm2 hot dip galvanized steel . Unprotected aluminum or copper clad aluminum conductors shall not be used for final underground connections to earth electrodes. A minimum of two separate dedicated and interconnected earth electrodes must be used for the earthing of the solar PV system support structure with a total earth resistance not exceeding 5 ohm. The earth electrodes shall have a precast concrete enclosure with aremovable lid for inspection and maintenance. The entire earthing system shall comprise non-corrosive components. 1.13 Surge Protection Surge protection shall be provided on the DC side and the AC side of the solar system.The DC surge protection devices (SPDs) shall be installed in the DC distribution box adjacent to the solar grid inverter.The AC SPDs shall be installed in the AC distribution box adjacent to the solar grid inverter.The SPDs earthing terminal shall be connected to earth through the above mentioned dedicated earthing system. The SPDs shall be of type 2 as per IEC

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60364-5-53 1.14 Junction Boxes Junction boxes and solar panel terminal boxes shall be of the thermo plastic type with IP 65 protection for outdoor use and IP 54 protection for indoor use. Cable terminations shall be taken through thermo-plastic cable glands. Cable ferrules shall be fitted at the cable termination points for identification.

1.15 Caution Signs The standard caution and danger boards or labels as per Indian Electricity Rules, the AC distribution box near the solar grid inverter and the building distribution board to which the AC output of the solar PV system is connected shall be provided with a no corrosive caution label.

1.16 Metering The existing service connection meter needs to be replaced with a bidirectional (import kWh and export kWh) service connection meter for the purpose of net-metering. Installation of the Solar Service Connection Meter will be carried out by DISCOM.It is mandatory that the Solar Rooftop PV system shall be connected to the Grid as per the guidelines of DISCOMs along with necessary protection devices. 1.17 Documentation The Installer shall supply the following documentation: a) System description with working principles. b) System single line diagram. c) Solar PV array lay-out. d) Routing diagram of cables and wires. e) Data sheets and user manuals of the solar PV panels and the solar grid inverter. f) A system operation and maintenance manual. g) Name, address, mobile number and email address of the service centre to be contacted in case of failure or complaint. h) Warranty cards. i) Maintenance registers.

1.18 Test Certificates and Reports to be Furnished Test Certificates / Reports from IECQ / NABL accredited laboratory for relevant IEC / equivalent BIS standard for quoted components shall be furnished.Type Test Certificates shall be provided for the solar modules and the solar grid inverter to provide evidence of compliance with standards as specified by Ministry of New nd Renewable Energy (MNRE). JVVNL.

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TECHNICAL SPECIFICATION FOR SUPPLY OF 33 KV HORN GAP FUSE SETS WITH POST 2X24 KV INSULATORS & 11 KV HORN GAP FUSE SETS WITH 1X24 KV POST INSULATORS

1.0 SCOPE :

This specification covers the design, manufacture, testing before dispatch, packing & forwarding and delivery of 33 KV Horn Gap Fuses and 11 kV Horn Gap Fuses (including hardwares and post insulators). The Horn Gap Fuses shall be required for protection of lines and distribution Transformers at various sites of Jaipur Discom, the details of principal parameters/various parts of horn gap fuses are indicated in subsequent clauses hereunder.

It is not the intent to specify completely herein all details of the design and construction of equipments. However, the equipment shall conform in all respects to high standards of engineering, design and workmanship and shall be capable of performing in continuous commercial operation upto the Bidder's guarantee in a manner acceptable to the Purchaser, who will interpret the meanings of drawings and specifications and shall have the power to reject any work or material which in his judgment is not in accordance therewith. The offered equipment shall be complete with all components necessary for its effective and trouble free operation along with associated equipments, interlocks , protection schemes etc. Such components shall be deemed to be within the scope of supply, irrespective of whether those are specially brought out in this specification and/or the commercial order or not.


2.2 The equipment i.e. horn gap fuse unit covered in this specification shall be a

complete unit with 2 x 24 KV Post Insulator type E-32 for use on 33 kV system and 1X24 KV Post Insulator type E-32 for use on 11 kV system The ratings of 33 kV & 11 KV Horn Gap Fuses with post insulators shall be as under :

PARTICULARS/ RATINGS HG FUSES

Specified values

(33 KV H.G.)

Specified values

(11 KV H.G.) a) Nominal system voltage kV (rms) b) Rated voltage kV(rms) c) Rated frequency(Hz) d) One minute power frequency withstand voltage kV(rms) (To earth & between poles). e) Impulse withstand voltage kV peak).(To earth & between poles). f) Permissible temperature rise above ambient

temp. ( 50 deg cent.) g) Rated Current (Amp)

33 36 50 70

170

40 deg. Cent. 200

11 12 50 55

125

40 deg. Cent. 100

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2.3 The minimum mechanical & electrical values/ characteristics of 24kV Post Insulators shall be as follows :

S. No. Particulars Specified values

1. Torsional Strength 680mm 2. Cantilever Strength 9000 N 3. Tensile Strength 30000 N 4. Compression Strength 40000 N 5 Highest system voltage (kV rms) 24 6. Dry & wet power frequency withstand

test voltage for one minute(kV rms)55

7. Impulse withstand test 125 (KV Peak) 8. Visible discharge test 18 (KV rms) 9. Power frequency puncture withstand

test voltage (kV rms) 1.3 times the actual dry flash-over voltage of the unit.

2.4 DIMENSIONAL CHARACTERISTICS OF POST INSULATORS :

---------------------------------------------------------------------------------------------------------------

S.No. Particulars. 2X24 kV 1X24 KV ( 33 KV HG fuse) (11KV HG Fuse )

------------------------------------------------------------------------------------------------------------

1. Nominal system voltage. 33 kV 11 KV 2. No. of units Two One

3. Total height of i) unit 254 mm 254mm

ii) Stack 508 mm

4. Diameter of Insula- 210 mm 210mm ting part (max.)

5. Minimum total creepage

distance of each unit 430 mm 430mm 6. Top fitting pitch 76 mm 76mm circle diameter

7. Bottom fitting 76 mm 76mm pitch circle

diameter ------------------------------------------------------------------------------------------------------

2.5 One set of Horn Gap Fuse Shall consist of three single phase units of Horn Gap Fuses.


HORN GAP FUSES :

3.1 The hardwares of horn gap fuses shall be designed and manufactured as per IS. The horn gap fuse sets are to be used for protection of lines and distribution

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transformers. The bill of material to complete one set (i.e. for Three phases) shall be as per requirement.

3.2 The hardwares of Horn Gap Fuses shall be constructed out of the best quality of

material suitable for weather conditions prevailing in Rajasthan. The workmanship shall be in accordance with the modern engineering practice. All ferrous parts shall be given an anticorrosive finish. The other parts shall be substantially non corrosive. The details of various specific parts for manufacture are as under :

(1) BASE CHANNEL :

The base channel shall be of size 125mmX60mmx542 mm Long( for 33 KV HG Fuse sets) and 75X40x542 mm Long ( for 11 KV HG Fuse sets) of Hot Dip Galvanized mild steel conforming to ISLC 75 of Tata Reference Book 1970 in case of 33 KV Horn Gap Fuses. The base channel should have holes for mounting post insulators.

(2) HORN STOOL :

Two numbers of Horn Stools of Hot Dip Galvanized MS flat of size 50 x 6 mm will be used. The Horn Stool shall be fixed on the top of the post insulators with the help of electro galvanized bolts and spring washers. The Horn Stool must be rigid and strong enough for fixing the horn over the top of horn stool. Over the top of the horn stool, the horn will be fixed.

(3) ARCING HORN :

Two numbers arcing horns of 12 mm dia of Hot Dip Galvanized M.S. round rod will be used. It will be aluminum painted. The base of arching horns should be projecting to 25 mm. It shall be fitted on horn stool with the help of horn clamps, nuts, bolts and spring washers. The length of the horn/height should be maintained. The horn should have a hole & fixing brass thumb screw with fly nut and flat washer to tie and tighten with the fuse wire.

(4) BRASS THUMB SCREW :

There shall be one tapped hole on each arcing horn. The brass thumb screw will be fixed in the tapped hole provided in each arcing horn. The fuse wire is to be tied with brass thumb screw and tightened with help of fly nut (Brass) and flat washer (Brass). The length of brass thumb screw will be fully threaded and screwed up to the whole depth of the horn. The design must be such that the changing of fuse wire is convenient. There is no loose connection/contact and there should not be any possibility of thumb/jamming on account of arcing when fuse is blown off.

(5) HORN CLAMPING ARRANGEMENT :

There shall be two M.S. Horn clamp of size 50x105x6 mm fixed on horn stool with the help of bolts and nuts, spring washers for fixing the arcing horns and clamping the conductor. The lower part of the clamping for holding the required conductor shall be of size 50x50x6

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mm. This shall be made from M.S. sheet. The clamp for 33 KV horn gap fuse shall be suitable for ACSR “DOG”.

(6) EARTHING TERMINAL :

One number earthing terminal shall be provided on the flange portion of base channel. The M.S bolt of 12 mm dia and 25 mm long shall be used with flat washer for this purpose.

(7) BOLTS, NUTS AND WASHERS :

All the bolts, nuts and washers shall be electro-galvanized. However the thumb screw and its connecting fly nut and flat washer, to be used to fix fuse wire, will be of brass only. The size of various bolts, nuts and washers which are in the scope of supply are as below :

--------------------------------------------------------------------------------------------------------------

S.NO. SIZE OF BOLTS, NUTS TO BE UTILISED FOR qty.for qty. for AND WASHERS. 1 unit 1 unit

of 33 KV of 11 KV ------------------------------------------------------------------------------------------------------------- 1. Bolt size 12mm dia, Earthing terminal 4 Nos. 4 Nos

25mm long with flat washer & nut.

2. Bolt size 12mm dia, 38mm long with nuts & spring washer.

For fixing post insulators on base.

8 Nos. 8 Nos

3. Bolt size 12 mm dia, 25mm long with nuts spring washers.

For fixing horn stool above the post insulators.

4 Nos .

4 Nos

4. Bolt size 5/6 dia 1.25” long with nuts and spring washers.

For fixing arcing horn on horn stool and clamping

16 Nos. 16 Nos

5. Brass thumb screw (6mm dia. 30mm long)

For fixing fuse wire on the arcing horn.

2 Nos. 2 Nos.

with Brass fly nut (30mm wing dia) flat washer (1mm thick, 20mm outer dia and internal dia. such as to accommodate the 6mm dia brass screw).

------------------------------------------------------------------------------------------------------

4.1 POST INSULATORS :

4.2 The 24 kV post insulators units shall be pedestal post type (conforming to IS- 5350 Part-III and IS-2544). The insulators shall be constructed out of the best quality of material suitable for weather conditions prevailing in Rajasthan.

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The workmanship shall be of the highest grade and the entire manufacture shall be in accordance with the modern Engineering practices.

4.2 Where Porcelain Insulators are offered, the insulator shall be made of

homogeneous and vitreous porcelain of high mechanical and die-electric strength. It shall have sufficient mechanical strength to sustain electrical and mechanical loading on account of wind load, short circuit forces etc. Glazing of the porcelain shall be of uniform brown or dark brown colour with a smooth surface arranged to shed away rain water. The porcelain shall be free from laminations and other flaws or imperfections that might affect the mechanical or dielectric quality. It shall be thoroughly vitrified, tough and impervious to moisture. The porcelain and metal parts shall be assembled in such a manner and with such material that any thermal differential expansion between the metal and porcelain parts throughout the range of temperature specified in this specification shall not loosen the parts or create undue internal stresses which may affect the mechanical or electrical strength or rigidity of the unit as a whole or stack of two units. The assembly shall not have excessive concentration of electrical stresses in any section or across leakage surfaces. Cement used in the construction of post insulators shall not cause fracture by expansion or loosening by construction and proper care shall be taken to locate correctly the individual parts during cementing. The cement used shall not give rise to chemical reaction with metal fittings and its thickness shall be uniform. The insulator shall be suitable for water washing by rain or artificial means in service condition. Profile of the insulator shall also conform to the relevant IS.

4.3 Cap to be provided on top of the insulator shall be of malleable steel

casting or of aluminum alloy . It shall be machine finished and hot dip galvanized in case of malleable steel casting. The cap of 24 kV Post Insulators shall have four numbers of tapped holes spaced on a pitch circle diameter of 76mm. The threads of the tapped holes in the post insulator metal fittings shall be cut after giving anti corrosion protection and shall be protected against rust by greasing or other similar means, all other threads shall be cut before giving anticorrosion protection and shall conform to IS:4218 or latest version thereof. The tapped holes shall be suitable for bolts with threads having anticorrosive protection. The effective depth of threads shall not be less than the nominal diameter of the bolt. The cap shall be so designed that it shall be free from visible corona.

4.4 The casting shall be free from blow holes, cracks and such other defects.

4.5 All the ferrous metal parts shall be given an anticorrosive finish and shall

be hot dip galvanized smoothly as per IS:3638 (as amended upto date), IS:2633 or any other equivalent authoritative standard. The other parts shall be substantially non corrosive. The material shall be galvanized only after shop operations upon it have been completed. The metal parts before galvanizing should be thoroughly cleaned of any paint, grease, rust, scales or alkali or any foreign deposit which are likely to come in the way of galvanizing process. The coating on the metal parts shall withstand minimum four one minute dips in copper sulphate solution as per the relevant IEC/IS.

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4.6 The insulator unit shall be assembled in a suitable jig to ensure correct

positioning of the top and bottom metal fittings relative to one another. The faces of the metal fittings shall be parallel and at right angles to the axis of the insulator and the corresponding holes in the top and the bottom metal fittings shall be in a vertical plane containing the axis of the insulator.

4.7 It shall be the sole responsibility of the Supplier to carry out thorough inspection

and quality checks on the insulators at the insulator supplier's works, before offering the insulators for Purchaser's inspection.

4.8 Two Nos. of 2 x 24 kV Post Insulator shall be provided on each pole of 33 kV

Horn Gap Fuse set (Total six Nos. of 2 x 24 kV Post Insulator for three phases (Poles) of one set of H.G.) Two Nos. of 1 x 24 kV Post Insulator shall be provided on each pole of 11 kV Horn Gap Fuse set . (Total six Nos. of 1 x 24 kV Post Insulator for three phases (Poles) of one set of H.G.)

4.9 The porcelain and hardware surface coming in contact with cement shall be

coated with bituminous paint for cushioning to relieve mechanical stress caused by temperature variation and cement expansion.

4.10 The post insulators shall conform to IS:5350. The total creepage distance of 24 kV

post insulator as individual unit shall be minimum 430 mm. 4.11 Following makes of the Post Insulators shall be acceptable for the supply of Horn

gap Fuse Set

i) M/s.Jaipur Glass & Potteries, Jaipur. ii) M/s.India Potteries, Kolkata. iii) M/s.Bikaner Ceramices, Bikaner. iv) M/s.CJI Porcelain, Khurja. v) M/s.Vishal Melleable, Ankeleshwar. vi) M/s.Allied Ceramices Pvt. Ltd., Kolkata. vii) M/s.WSI, Chennai. viii) M/s.IEC, Bhopal. ix) M/s.MIL, Allahabad. x) M/s.Jay Shree Insulators, Vadodara. xi) M/s.Birla NGK Insulators Pvt. Ltd., Halol. xii) M/s.MIL, Abu Road. xiii) M/s.Sarvana Insulators Ltd., Kurinji Padi, Dist Cuddalore,

(Tamilnadu). xiv) M/s B.H.E.L.

4.12 Besides above, the Post Insulators manufactured by the vendors approved by the Power Grid Corporation of India Ltd (PGCIL) and National Thermal Power Corporation (NTPC) shall also be acceptable.

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5.1 TESTS :


The parts of H.G. Fuses i.e. Hardwares and post insulators shall be subject to under mentioned tests separately at respective manufacturer’s works before dispatch as per relevant standards.

INSULATORS :

A) Routine test

i) Visual examination ii) Routine electrical test iii) Routine mechanical test

B) TYPE TESTS

i) Visual examination ii) Verification of dimensions iii) Visible discharge test iv) Impulse voltage withstand test. v) Dry power-frequency voltage withstand test. vi) Wet power frequency voltage withstand test. vii) Temperature cycle test.

viii) Mechanical strength : a) Bending Test b) Torsion Test. c) Tensile or compressive test.

ix) Puncture test. x) Porosity test. xi) Galvanizing test.

C) Acceptance Tests :

i) Verification of dimensions ii)Temperature cycle test iii)Mechanical strength test iv)Puncture test v)Porosity test vi)Galvanizing test

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TEST ON HORN GAP FUSE UNIT COMPLETE WITH INSULATORS AND HARDWARES

A TYPETEST (S) :

i) Visual examination ii) Dimensional checkup iii) Temperature rise test iv) Power frequency H.V.Test, with inter phase distance as 1000 mm.( for

33 KV HG fuse set) and with inter phase distance as 600 mm.( for 11 KV HG fuse set)

v) Impulse test. with inter phase distance as 1000 mm.( for 33 KV HG fuse set) and with inter phase distance as 600 mm.( for 11 KV HG fuse set)

B ACCEPTANCE TESTS :

i) Visual examination ii) Dimensional checkup iii) Temperature Rise Test

On one sample per lot 5.3 TEST ON BOUGHT OUT ITEMS :

Tests are not required to be performed on small bought out parts like Nuts, Bolts & Washers etc. at the works of manufacturer. Furnishing of test certificates from original manufacturer(s) shall be deemed to be satisfactory evidence. Inspection of the tests at sub contractor's works will be arranged by the supplier when ever required.

5.4 ACCEPTANCE & ROUTINE TESTS :

5.4.1 All acceptance & routine tests as stipulated at clause No.6.1 shall be carried out

in presence of purchaser's representative at manufacturer's works of Insulators and Hardwares separately before dispatch.

5.4.2 Immediately after finalization of the programme of type/acceptance, routine

testing, the supplier shall give sufficient advance intimation to the purchaser to enable him to depute his representative for witnessing the tests.

The test samples after having withstood the routine tests shall be subjected to the following Acceptance tests in the order indicated below :

On Insulators

i) Verification of dimensions as per approved drawing / ISS. ii) Temperature cycle test. iii) Mechanical strength test. iv) Puncture test. v) Porosity test

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vi) ) Galvanizing test On Hardwares of Horn Gap Fuse sets

i) Visual examination ii) Dimensional checkup iii) Temperature Rise Test (only on one unit per lot)

Fitment of Horn gap Fuse hardwares with Insulator test

One percent of insulators inspected shall be brought at the contractor works for checking of fitment with hardware.

5.4.3 For conducting acceptance tests on post insulators the number of post insulators or

post insulators unit shall be selected as under:-

Lot size number of post insulators unit to be selected

Upto 800 6

801 to 1300 8

1301 to 3200 10

3201 to 8000 14

8001 and above 20

5.4.4 10% samples will be selected from offered lot of complete Horn Gap Fuse sets Hardwares for conducting acceptance tests on the same except fitment test which shall be carried out on one percent of offered lot.

6.1 TYPE TEST CERTIFICATE:

a) The bidder shall furnish valid and authenticated type test certificate from a Govt. approved/ a Govt. recognized/ NABL accredited laboratory/ ILAC i.e. International Laboratory Accredited laboratory / ILAC i.e International Laboratory Accreditation Cooperation ( In case of foreign laboratory) of similar rating and design. Such type test certificates should not be older than three years as on the date of bid opening. For this purpose date of conducting type tests will be considered.

b) The type test certificates by in house laboratory of tendering firm even if it is a Govt

approved/ Govt recognized/ NABL accredited/ ILAC accredited, shall not be accepted, in case of their own tender. This will not apply if tendering firm is Govt. Company/ Public Sector Undertaking.

c) The bidder should furnish documentary evidence in support of the laboratory whose

type test have been furnished, that the said laboratory is a Govt/ a Govt. approved/ a Govt. recognized/ NABL accredited laboratory/ ILAC accredited ( in case of foreign laboratory)

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d) The type test certificates shall be furnished either in original or duly attested by

notary.

e) The bids of only those bidders shall be considered to be meeting the type test criteria who furnishes complete type test certificates with the bid as per above provision.

7.Calibration Certificates:

The supplier shall present the latest calibration certificate(s) of testing instruments / equipments to be used for the testing of the materials covered in the purchase order to the authorized inspecting officer/ inspecting agency of the purchaser. The testing instruments / meters/ apparatus etc. should be got calibrated by the supplier from time to time from independent laboratory accredited from NABL or the manufacturer of the testing instruments having traceability to NPL or NABL accredited laboratory. The calibration certificates should not in any case be older than one year at the time of presenting the same to the inspecting officer/ inspecting agency of the purchaser. The testing instruments / equipments should be duly sealed by the calibrating agency and mention thereof shall be indicated in the calibration certificates(s). 8.0 DRAWING :

8.1 The one set of following drawings/documents of the equipment covered by this specification shall be furnished by the Bidder along with their offer:-

i) Outline dimensional drawings of Horn Gap Fuse Set with insulator and list mentioning bill of material with complete details regarding metal hardware fittings.

ii) Assembly drawings showing complete details of all parts and separating mechanism and mass of main component part.

iii) Drawings showing dimension of upper and lower metal parts along with PCD of post insulator.

iv) Descriptive literature and manufacturing data on insulator shall be furnished.

v) Type test reports vi) Test reports, literature, pamphlets of the bought out items and raw materials.

vii) Detailed views of the insulator stacks & metallic and hardware unit. 8.2 The manufacturing of the equipment shall be strictly in accordance with the

approved drawings and no deviation shall be permitted without the written approval of the Purchaser. All manufacturing and fabrication work in connection with the equipment prior to the approval of the drawing shall be at the Supplier's risk.

8.3 Approval of drawings/work by Purchaser shall not relieve the Supplier of his responsibility and liability for ensuring correctness and correct interpretation of the latest revision of applicable standards, rules and codes of practices.

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9.0 PACKING AND FORWARDING :

9.1 Each Horn Gap Fuse Set Hardwares shall be legibly and indelibly marked to show the following :

a) Name or trade mark of manufacturer.

The Post Insulators shall be legibly and indelibly marked to show the following :

a) Name or trade mark of manufacturer.

b) TN/IPDS/TW Such marking on porcelain shall be printed, not embossed and shall be applied before firing.

9.2 The Horn Gap Fuse sets (hardwares) shall be suitability packed in double gunny

bags worthy of rail/ road transport . The supplies shall have to insert in each case / bag packing list giving item wise details of articles in the packing as mentioned in the list. The post insulators shall be packed in crates suitable for vertical/ horizontal transport as the case may be and suitable to withstand handling during transport and outdoor storage during transit. The Supplier shall be responsible for any damage to the equipment during transit due to improper and inadequate packing. The easily damageable material shall be carefully packed and marked with the appropriate caution symbols.

Wherever necessary, proper arrangement for lifting, such as lifting hooks etc., shall be provided. Any material found short inside the packing cases shall be supplied by Supplier without any extra cost.

The inspected lot of Post Insulators should be directly delivered / dispatched from their ( manufacturer’s) works to consignee’s stores.

9.3 Each consignment shall be accompanied by a detailed packing list containing

the following information :

a) Name of the consignee. b) Details of consignment. c) Destination. d) Total weight of consignment. e) Handling and unpacking instructions. f) Bill of material indicating contents of each package.

10.1 TEST CHECKING OF MATERIAL AT STORES:

The material received in the stores of the NIGAM shall be subjected to the test checking at stores before final acceptance of the material, the procedure for the same shall be as under : 10.2 SAMPLING

One sample out of each sub lot/ lot of 50 sets for 33 KV Horn gap fuse sets and 100 sets for 11 KV Horn Gap fuse sets or part thereof from each inspected lot received in stores shall be selected from each store for test checking of material and shall be got tested.

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The selection of sample from the material received at stores shall be done as soon as material is received in stores without the presence of the representative of the supplier. However, testing of sample(s) at CTL or elsewhere as arranged by JVVNL shall be carried out in the presence of representative of the supplier after identification / confirmation by him that sample so selected belongs to them.

10.1 (a) one extra sample of 24 KV post insulator for conducting Puncture test. At present since the facility for Puncture test is not available at Ajmer and Jodhpur Discom as such till such time this facility is made available, Puncture test on the samples selected from the supply received at stores of Ajmer & Jodhpur Discom shall be carried out at CTL, Jaipur.

10.2 TESTS


a) Visual examination , verification of dimensions, weight and marking as per PO/ GTP / approved drawing.

b) Post Insulators : - i) Mechanical strength test. ii) Porosity Test iii) Puncture Test

c) All galvanized parts. - Uniformity of galvanization test.

Testing of the material shall shall be got done at the test laboratory of he Nigam i.e. at CTL in the presence of the representative of the supplier. Only those test shall be conducted at CTL for which facility with CTL is available.

i) For witnessing of the testing, clear 7 days notice shall be given to the supplier stating date, time & place where the test is to be conducted. The testing shall be started after identification / confirmation of sample by the representative of the supplier that sample selected for testing pertain from the lot supplied by them. In case the supplier does not attend for witnessing the testing, the testing shall be proceeded and completed and action be taken as per the contract.

ii) The CTL shall send copies of test reports to the purchaser, consignees and the supplier.

10.3 CRITERIA FOR ACCEPTANCE In case of failure of any of sample (s) in any of the above tests, the material contained in the lot / sub-lot received in store to which the samples belong, shall be rejected. The rejected material shall have to be replaced by the supplier free of cost.

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TECHNICAL SPECIFICATION OF P.G. CLAMPS FOR DOG, PANTHER CONDUCTOR AND T-CLAMP FOR PANTHER CONDUCTOR

1.0 SCOPE

This specification covers the manufacture, testing before dispatch and delivery at our Stores/ Site of P.G. Clamps for ACSR Panther, Dog Conductor and T-clamp for Panther Conductor as detailed hereunder:-

2.0 MATERIAL:-

All material used shall conform to the relevant ISS. All aluminum and aluminum alloy used in the manufacture of the connector(s) shall conform to designation À6’ of IS:617 (1975) Latest amended and IS:1367 (latest amended). Non ferrous alloy bolts, nuts and spring washers shall conform to the relevant Standards.

The material used in the manufacture of clamps shall be Aluminum alloy 4600 of IS:617- 1994 as amended and shall be gravity die casting process only.

Steel Bolts and Nuts shall conform to IS:1368-1992 & IS:1367/1979-80 (with latest amendment, if any)

All ferrous metal parts intended for outdoor use except those made of stainless steel shall be protected by hot dip galvanizing in accordance with IS:2633-1986.

The temperature rise of power connectors above a reference ambient temperature of 40 Deg. C when carrying rated current as above shall not exceed 45 Deg. C to fulfill the requirement of Cl.6 IS:5561(1970).

3.0 GENERAL REQUIREMENTS:-

The power connectors shall be smooth and free from cavities, blow-holes and other defects and such adverse effects like sharp radii of curvature, ridges & excrescence which might lead to localized pressure or damage to conductor in service. Power connectors shall be so designed and proportioned that they are capable of safely withstanding stresses to which they may be subjected (including these due to short circuit and climatic conditions) and that the effect of vibrations, both on the conductor and the connector itself are minimized. Sufficient contact pressure should be maintained at the joint by the provision of the required number of bolts or other fixing arrangements. But the contact pressure should be evenly distributed by the use of pressure plates, washers or suitable saddles of adequate area & thickness.

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4.0 DIMENSIONAL REQUIREMENT FOR P.G.CLAMPS & T-CLAMPS :-

s.no PARTICULARS PG CLAMPS FOR T-CLAMP ACSR

PANTHER ACSR DOG TO DOG

FOR PANTHER

TO PANTHER

TYPE À’ CONDUCTOR

a.) CONDUCTOR:-

1. No. of strands in Conductor

Al. 30/ 3.00 mm Steel 7/ 3.00 mm

Al. 6/ 4.72 mm Steel 7/ 1.57 mm

Al. 30/ 3.00 mm Steel 7/

3.00 mm 2. Conductor dia

21.0mm

14.15mm 21.0 mm

b.)CLAMPS

1. Length (Min.) 135mm

125mm

80 mm

2. Thickness of Metallic Parts (Min.)

10 mm

10mm

10mm

3. No. of Bolts along with lock nuts plain washer and spring washers (Min.)

3

3

12

4. Size of Bolts Dia X Length (Min.)

12mm x 60mm 12mm x 50mm 10mmx 65mm

5. Short circuit level for 1 Sec. 25 kA 16 kA 31.5KA

6. Rated current Amps. 630 400 800

7. Weight (In Kg) Tolerance in weight :- (-2%)

Al:- 0.550 Steel:-0.250 Total:- 0.800

Al:- 0.425 Steel:-0.210 Total:-0.635

Al:- 0.550 Steel:-0.600 Total:- 1.150

Note:- Bidders are requested to quote alternative prices for P.G. Clamps suitable for ACSR Dog to Dog for the Type À’ & Type `B’.

5.0 TYPE TESTS:-

a) The bidder shall furnish valid and authenticated type test certificate from a Govt. approved/ a Govt. recognized/ NABL accredited laboratory/ ILAC i.e. International Laboratory Accredited laboratory / ILAC i.e International Laboratory Accreditation Corporation ( In case of foreign laboratory) of similar rating and design of tendered material. Such type test certificates should not be older than five years as on the date of bid opening. For this purpose date of conducting type tests will be considered.

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b) The type test certificates by in house laboratory of biding firm even if it is a Govt approved/ Govt recognized/ NABL accredited Laboratory / ILAC accredited, shall not be accepted, in case of their own bid. This will not apply if biding firm is Govt. Company/ Public Sector Undertaking.

c) The bidder should furnish documentary evidence in support of the laboratory whose type test have been furnished, that the said laboratory is a Govt/ a Govt. approved/ a Govt. recognized/ NABL accredited laboratory/ ILAC accredited ( in case of foreign laboratory)

d) The type test certificates shall be furnished either in original or duly attested by notary.

e ) Following type test shall be conducted on Clamps :-

a) Tensile test b) Temperature test. c) Resistance test. d) Dimensional test. e) Galvanizing test f) Short circuit test

The short circuit test shall be accompanied with the detailed dimensional drawing duly signed by the testing agency.

6.1 INSPECTION AND TESTING

i) The material shall be tested and inspected by an authorized inspecting officer of the Nigam before dispatch. Samples shall be drawn for inspection/ testing as per provisions of relevant ISS/Purchase Order. The purchaser reserves the right to get the material tested in any testing laboratory before dispatch.

ii) The suppliers should satisfy themselves that the stores are in accordance with the terms of the contract and fully confirm to required specifications by carrying out a thorough pre-inspection of each quota before tending the same for inspecting to the inspecting officer nominated by the purchaser. Such pre-inspection on the part of the suppliers would minimize the chances of rejection in inspection. The following shall constitute Acceptance Tests:-

i) Tensile Test. ii) Resistance Test. iii) Dimensional Check. iv) Galvanizing Test, where applicable.

In the event of order temperature rise test shall be carried out once on one Clamp of each type from the first offered lot in the presence of Purchaser’s representative without extra charges.

The following shall constitute Routine Tests:-

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i) Visual inspection. ii) Dimensional check.

7.1 TEST CHECKING OF MATERIAL AT STORES:-

The material received in the Stores of the Nigam shall be subjected to the test checking

at Stores before final acceptance of the material. The procedure for the same shall be as under:-

A) Sampling:-

One sample out of each sub lot/ lot of 1,000 Nos. or part thereof from each inspected lot of each type of clamp received at Stores shall be selected for test checking of material & shall be got tested. The selection of sample from the material received at stores shall be done as soon as material is received in stores without the presence of the representative of the supplier. However, testing of sample(s) at CTL shall be carried out in the presence of representative of the supplier after identification / confirmation by him that sample so selected belongs to them.

B) Tests:-

The following tests shall be carried out on the above items:-

a. Visual Examination, Verification of Dimension, weight and marking as per ISS/ Specification.

b. Tensile Test

c. Resistance Test

d. Galvanizing test

Testing of the material shall be got done at the test laboratory of the NIGAM i.e. at CTL in the presence of the representative of the supplier.

For witnessing of testing, clear 7 days notice shall be given to the supplier by fax / speed post stating date, time & place where the test is to be conducted. In case the supplier do not attend for witnessing the testing, the testing shall be proceeded and completed and action be taken as per the contract.

The Officer Incharge of Central Testing Lab (CTL) Jaipur shall send copies of test

reports to the purchaser, consignees and the supplier.

C) CRITERIA FOR ACCEPTANCE

a) Visual Examination, Verification of Dimension, weight and marking:

As per ISS/ Specification

b)Tensile Test AND

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c) Resistance Test:-

In case of failure of sample in Tensile Test & Resistance test, the material contained in the lot/ sub-lot to which the sample belongs shall be rejected. The rejected material shall have to be replaced by the supplier free of cost.

d) Galvanizing Test:

i) The sample(s) shall be first tested for (n-2) number of dips where(n) is specified

number of dips in the contract. If the sample(s) does not pass the uniformity of

Galvanization Test for (n-2) dips, the material shall be rejected and the material

relating to relevant lot/ sub-lot to which sample(s) pertains shall have to be replaced

by the supplier free of cost.

ii) If the sample has passed the uniformity of Galvanization Test for (n-2) dips, then it

shall be tested for (n-1) dips. If the sample has not passed the uniformity of Galvanization Test with (n-1) dips, then material pertaining to relevant lot/ sub-lot shall be accepted with a deduction @ 10% of cost of material.

iii) If the sample has passed the uniformity of Galvanization Test with (n-1) dips, then

sample shall be tested for last one dip of one minute to complete the test for `n’ dips.

If the sample does not pass the uniformity of Galvanization Test with `n’ dips, then

the material pertaining to relevant lot/sub-lot shall be accepted with a deduction @

5% of cost of material.

8.0 MARKING

The items to be supplied shall be indelibly marked with suitable marks so as to identify the same. The Clamps shall be marked with `Rated Normal Current' and name of the `Conductor' for which the same is suitable viz. Panther to Panther, Dog to Dog, Rabbit to Rabbit and weasel to Weasel.

9.0 PACKING

You shall pack the material in the suitable double gunny bag or double HDPE bags so that the material may not be damaged in the transit

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10.0 GUARANTEED TECHNICAL & OTHER PARTICULARS.

The tenderer shall furnish complete guaranteed technical particulars

11.0 DRAWING :

The successful bidder will submit the full dimensional drawings on A-3 size paper in triplicate for our approval before commencement of supply. If the successful bidder manufacture the equipment without obtaining approval of drawing, the purchaser will not be responsible if any part is not as per required dimensions. Approval of drawings/work by Purchaser shall not relieve the Supplier of his responsibility and liability for ensuring correctness and correct interpretation of the latest revision of applicable standards, rules and codes of practices.

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TECHNICAL SPECIFICATION FOR11 KV 45 KN DISC INSULATORS T&C TYPE.& 11 KV 45 KN DISC INSULATORS B&S TYPE

1.0 SCOPE :

1.1 This section covers for the design, manufacture, testing at manufacturer's

works before dispatch, supply and delivery of Disc Insulators Tongue& Clevis type and Ball & Socket type for various overhead 33 KV an 11 KV Power Lines and overhead 132/33 KV Power Lines. The description of insulators & string arrangements have been given in Appendix- I, Appendix-II and Appendix-III

2.0 STANDARDS :

The Disc Insulator shall comply in all respects with the Indian Standard

Specifications IS:731-1971 (Second Revision), IS:3188-1980, IS:2486 (Part-I)-1993 (Second Revision),IS:2486 (Part-II) 1989 (Second Revision) and IS:2486 (Part-III)1974, IS:2486(Part.IV)1981 with latest amendments. The galvanisation of metallic parts shall conform to IS:2633/1972(Latest amendments). The Insulator String shall consist of discs (B&S Type) of dimensions specified in Appendix-I, for use on 3 phase, 50 cycle power system . All applicable standards shall be clearly mentioned in schedule-III

3.0 MATERIALS,DESIGN & TYPE :

3.1 All the materials used in the manufacture of the insulators shall be of the first class

quality. The porcelain shall be sound, free from defects thoroughly vitrified and smoothly glazed.

3.2 The glaze shall be brown in colour . The glaze shall cover all the porcelain parts

of the insulators except those areas which serve as supports during firing or are left unglazed for the purpose of assembly . The glaze shall be uniform, smooth, hard, dense, continuous and brilliant.

3.3 The design of the insulator shall be such that stresses due to expansion and

contraction in any part of the insulator shall not lead to deterioration. The porcelain shall not engage directly with hard metal.

3.4 Cement used in the construction of the insulator shall not cause fracture by expansion or loosening by contraction and proper care shall be taken to locate the individual parts, correctly during cementing . The cement shall not give rise to chemical reaction with metal fittings and its thickness shall be as uniform as possible.

3.5 All parts of different fittings which provide for interconnection shall be made such

that sufficient clearance is provided at the connection point to ensure free movement and suspension of the insulator string assembly.

3.6 All hardware fittings (except those specified otherwise) shall be made of drop forged steel or heat treated malleable cast iron, and shall be hot dip galvanized

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after all machining and fittings have been completed. The material used in fittings shall be corrosion resistant.

3.7 The locking devices shall be resilient, corrosion resistant and of suitable

mechanical strength. The hardness and temper of the material are important for their satisfactory operation.

The locking devices shall retain their locking ability after being operated from the locking to the coupling position at least twenty times at normal temperature. They should be effective at the lowest temperature likely to be encountered in service.

3.8 For Ball & Socket type disc insulators the cap and the pin shall be heavily

galvanised and mechanically strong. The ball shall move freely in the cap sockets, but shall be so designed that they do not give way while in service. The dimensions of the pin ball & socket shall be conforming to ISS 2486/part -II. The cap shall be made of malleable cast iron confirming to IS:2108-1977. These shall be free from cracks, shrinks, air holes, burs and rough edges. The caps shall be circular, with inner and outer surfaces concentric and of such design that they will not yield or distort under the stress to the porcelain shells. The pin shall be single piece made of drop forged steel and shall be free from laps, field's burs and rough edges. All bearing surfaces shall be smooth and uniform so as to distribute the loading stresses uniformly. The pins shall be of such a design that they will not yield or distort under loaded condition. They shall not be made by joining, welding, shrink fitting or any other process from more then one piece of material. The locking devices `W/R' type for Ball & Socket lockers shall be either of Phosphor bronze confirming to IS:7814-1975 or stainless steel confirming to IS:6603-1972 with minimum hardness of 160 HV. The dimensions shall confirm to IS:2486(Part-3)-1974.

3.9 The dimension of the clevis and tongue connection shall be as shown infig.25 and the dimension of cross arm strap shall be as shown in fig.26 of IS:2486/Pt.II/1989 ( latest amendments)

The tongue and clevis type porcelain insulators shall be as per fig.2 and its

dimension shall conform to table-2 of IS:3188/1980 (latest amendments)

The dimensions of pin ball socket shall be according to fig.8 and 9 respectively of IS:2486 (Part.II/1989) IInd revision.

4.0 CLASSIFICATION SIZE & NO. OF DISCS :

4.1 The insulators shall be of type B as specified under clause 5 "Classification" of

IS:731-1971(second revision). 4.2 The long rod Insulator falling under type A shall confirm to IEC:433-1980(with latest

amendments )& IEC-575/1977. 5.1 TESTING :

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5.2 Sampling inspection, testing and acceptance of insulators shall be in accordance with the latest revision of IS:731/1971 while that of hardware associated with these discs shall be as per IS:2486(Pt.I)/1993 (second revision) IS:2486(Pt. II)/1989 (second revision) and IS:2486(Pt.III)/1974 & IS:3188-1980 with latest amendments. Sampling inspection, testing and acceptance of long rod insulators shall be in accordance with the latest edition of IEC :433/1980 & IEC:575/1977.

6.0 MECHANICAL LOADS :

The insulator strings shall be suitable for the minimum failing loads specified in

Table-2, clause 7 of IS:731/1971 (IInd Revision). The load shall be supplied axially to the insulator strings.

7.1 MARKINGS :

Each insulator shall be legibly and indelibly marked to show the following :

a) Name or trade mark of the manufacturer. b) TW/TN NO. c) Minimum failing load in KNewton.

Marking on porcelain shall be originated and shall be applied before firing.

8.0 CREEPAGE DISTANCE :

The tenderer shall specify in his tender the creepage distances of the insulator.

These values should not be less than those specified in IS:731-1971 & IS:3188-1980 (Latest amendment).

9.0 CRITERION OF CONFORMITY : 9.1 The criterion of conformity to the requirements of the tests given in 3.11.2 shall be

as per clause No.C-2, of Appendix 'C' of IS:731/1971 (second revision). 9.2 No part of the lot withdrawn as described in 3.12.1 above shallconstitute part of

any other test submitted for the first time. 10.0 ROUTINE TESTS :

Routine tests shall be carried out on each insulator & to check requirements which are likely to vary during production as per relevant IS:731/1971 (with latest amendments).

11 PACKING :

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All insulators shall be packed in suitable crates or boxes with suitable steel bands so as to withstand rough handling and storage at destination.The gross weight of packing shall not exceed 50 Kgs.

12 DRAWINGS :

The bidder shall submit detailed drawings showing design and dimensions of insulator , ball pin, socket cap & security pin . The type of the material used for various parts shall be clearly specified on the drawing.

13TEST CHECKING OF MATERIAL AT STORES


i) SAMPLING

One sample out of each sub-lot / lot consisting of following quantities or part thereof in case of each type of insulators from each inspected lot received in stores shall be selected from each store for test checking of material and shall be got tested.

i(a)one extra sample of Disc insulator of each type for conducting Puncture test.

11 KV 45 KN Disc insulator “T&C” Type – 1000 Nos. 11 KV 45 KN Disc insulator “B&S” Type – 1000 Nos

The sample selection shall be done as soon as the material is received in stores, without

calling the representative of supplier. However, testing at CTL or else where as arranged

by NIGAM shall be done in the presence of representative of supplier after identification/

confirmation by the supplier’s representative that sample(s) so selected belong to them.

ii) TESTS


a) Visual examination, verification of dimensions, creepage distance etc. b) Mechanical failing Load Test c) Porosity test d) Puncture Test

However, only those tests shall be conducted at CTL for which facility with CTL is available.

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TECHNICAL SPECIFICATION OF LT PIN INSULATORS AND 11KV & 33 KV GUY (STAY)INSULATORSFOR 11 KV& 33 KV TRANSMISSION AND L.T.DISTRIBUION OVERHEAD POWER LINES ------------------------------------------------------------------------------------------------------------------

1.0 SCOPE :

1.1 This section provides for design, manufacture, inspection & testing before dispatch, supply and delivery of Porcelain 11 KV Guy (Stay) insulators, 33 KV Guy (Stay) insulators and L.T. Pin Insulators specified herein for their satisfactory use and operation on various 11 KV and 33KV sub-transmission & L.T. distribution overhead power lines of the state.

1.2 It is not the intent to specify completely herein all the details of the design and construction of equipment. However, the equipment shall conform in all respect to high standards of engineering, design and workmanship and shall be capable of performing in continuous commercial operation up to the bidder's guarantee, in a manner acceptable to the purchaser, who will interpret the meanings of drawings and specification and shall have the power to reject any work or material which in his judgment is not in accordance therewith. The offered equipment shall be complete with all components necessary for their effective and trouble free operation. Such components shall be deemed to be within the scope of bidder's supply irrespective of whether those are specifically brought out in this specification and / or the commercial order or not.\


2.1 The material shall conform to the following specific parameters :

S.N. Item Specification ---- ---- ---------------------

1. Type of Installation Outdoor 2. System Voltage 415 Volt (+10%, -15%) 3. System frequency 50 Hz, + 5% 4. Number of phases Three 5. System of earthing Solidly grounded.

2.2 Details of insulators :

2.2.1 The all type of Insulators shall be suitable for use on various 11 KV/33 KV and

L.T. distribution Power lines in a moderately polluted atmosphere.

2.2.2 The 11 KV Guy (Stay ) insulators shall of size110x75x22mm having dimensions as per fig 2 and 33 KV Guy Insulators shall of size 140x85x25mm having dimensions as per fig.3 of IS:5300/1969 (latest amended).

2.2.3 The 11 KV/33KV Guy (Stay ) insulators shall be brown glazed and conforming to

IS:5300/1969 (Latest amended) in all respects.

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2.2.3 The L.T. Pin insulators shall of size 100x70mm having dimensions as shown in Fig.1, type-1 of IS:1445/1977 (latest amended).

2.2.3 The L.T.Pin Insulators shall be brown glazed and conforming to IS:1445 / 1977

(Latest amended) in all respects. 3.0 GENERAL TECHNICAL REQUIREMENTS :

3.1 The porcelain of Insulators shall be sound, free from defects, thoroughly vitrified

and smoothly glazed. 3.2 The glaze of the insulators shall be brown in colour. The glaze shall cover the

entire porcelain surface parts except those areas that serve as supports during firing or are otherwise required to be left unglazed.

3.3 The design of the insulator shall be such that the stresses due to expansion & contraction in any part of the insulator shall not lead to its deterioration.

3.4 The dimensions of guy strain insulators essential from the point of view of inter-changeability shall be in accordance with IS:5300/1969(latest amended).

3.5 The insulator shall be in one piece. 3.6 The Pin Insulators shall have a top groove and both type of insulators shall

have dimensions as specified above. 3.7. The Pin Insulators shall be threaded to take mild steel pins having profile as

IS:1445/1977 (Latest amended). 4.1 INSULATOR CHARACTERISTICS :

A. The 11 KV & 33KVGuy (Stay ) insulators shall have the electrical &

Mechanical characteristics as given below: 11 KV 33KV

1. Designation of insulator B C 2. Length (mm) 110 140 3. Diameter (mm) 75 85 4. Cable hole dia (mm) 22 25 5. Minimum failing load KN 53 88 6. Creepage distance 48 57 7. Dry one minute power 22 27

frequency withstand voltage KV (rms)

8. Wet one minute power 9 13 frequency withstand voltage KV (rms)

-----------------------------------------------------------------------------------------------------------------

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B.T he L.T. Pin Insulators shall have the electrical &Mechanical characteristics as given below:

1. Type of Insulator Pin Insulator

2. Size of Insulators (mm) 100x70 3. Dry power frequency 23

withstand Voltage KV (rms) 4. Wet power frequency 10

withstand Voltage KV (rms) 5. Power frequency puncture 1.3 x the actual

withstand voltage KV (rms) dry flash over voltage. 6. Min. failing load(KN) 3.5 ------------------------------------------------------------------------------------------------------------


5.1 Each insulator shall be legibly and indelibly marked to show the following:

i) Name or trade mark of the manufacturer.

ii) Month &Year of manufacture. iii) Minimum failing load in KN iv) ISI certification mark if any. v) IPDS/TN NO./TW

5.2 Marking on porcelain shall be printed & shall be applied before firing.

5.3 Offer not complying the condition of marking shall be treated as non-responsive.

5.4 The insulators marked with ISI Certification Mark will be given preference

6.1 DRAWINGS &DOCUMENTATION :

6.2 The bidder shall furnish full description and illustrated catalogues of insulators offered along with the bid.

6.3 The bidder shall also furnish along with the bid the outline drawing of each insulator unit comply with relevant standard with latest amendment including cross- sectional view of the shell. The drawing shall include the following information :

i) Shell diameter and unit spacing with manufacturing tolerance. ii) Weight of unit insulator.

iii) entification mark. iv) Manufacturer's catalogue number. v)Brief installation instructions.

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7.1 TESTS :


The insulators shall be subjected at contractor's works before dispatch, to the routine & acceptance tests given here under as per relevant IS with latest amendment.

7.3 ROUTINE TESTS :

These tests are to carried out to check various requirements of insulators which are likely to vary during production. The following tests shall be conducted / carried out on each insulator by the bidder at his works as per relevant IS with Latest amendment and he should furnish certificate / record thereof during pre-dispatch inspection:-

i) Visual Examination


These tests shall be carried out on the samplestaken from the lot for the purpose of the acceptance of that lot and shall be carried out by the bidder in the presence of the

purchaser's representative(s). The following tests should be conducted in the order given below as per relevant IS with latest amendment:

i) Verification of dimensions ii) Temperature Cycle test iii) Mechanical strength test iv) Porosity Test

7.5 TYPE TESTS :

7.4.1 The type tests to be conducted on at least two units 11 KV & 33 KV Guy Insulators as per relevant IS:5300/1969 (latest amended). The following tests shall constitute the type tests and shall be conducted in the order given below :

(i) Visual examination (clause 7.8) (ii) Verification of dimensions (clause 7.5) (iii) Dry one minute power frequency withstand test(clause 7.2) test (clause 7.3) (v) Temperature cycle test (clause 7.6) (vi) Mechanical strength test (clause 7.4) (vii) rosity test (clause 7.7)

7.4.2 The type tests to be conducted on at least two units of LT Pin insulators as per relevant IS:1445/1977 (latest amended). The following tests shall constitute the type tests:

(i) Visual examination (clause 8.4) (ii) Verification of dimensions (clause 8.5) (iii) Dry power frequency voltage withstand test(clause 8.6) (iv) Wet power frequency voltage with stand test (clause 8.7) (v) Temperature cycle test (clause 8.8) (vi) Mechanical failing load test (clause 8.9) (vii) wer frequency puncture withstand test (clause 8.10) (viii) Porosity test (clause 8.11)

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However, the purchaser reserves the right to demand repetition of some or all the type tests in presence of purchaser's representative. For this purpose , the tenderer should indicate unit rate for carrying out such type tests. These test charges shall not be taken into consideration for bid evaluation.

8.0 SAMPLING :

The sampling procedure as laid down in IS:731/1971 with latest amended (For Guy Insulators) and IS 1445/1977 with latest amendment (For LT Pin Insulators) shall be followed for carrying out specified acceptance tests.

9.0TOLERANCE ON DIMENSIONS / TEST RESULTS :

As per IS:5300/1969 with latest amendments ( For 11 KV & 33 KV Guy Insulators).As per IS:1445/1977 with latest amendments ( For LT Pin Insulators).


The purchaser reserves the right to conduct all tests on each type of insulator after arrival at site and bidder shall guarantee test certificates figures under actual service conditions.


The bidder must indicate clearly about the various testing facilities for conducting various acceptance tests as well as routine tests as per relevant ISS as available at his works. In case no testing facilities are available at the bidder's works, particulars of the place where such testing is proposed to be conducted during course of inspection must be indicated.

12.1 TEST CHECKING OF MATERIAL

The material received of the NIGAM shall be subjected to the test checking at stores before final acceptance of the material, the procedure for the same shall be as under :

12.2 SAMPLING

One sample out of each sub-lot / lot of 3000 Nos. or part thereof from each inspected lot of each type of insulators received in stores shall be selected for test checking of material and shall be got tested. The sample selection shall be done in the presence of supplier or his authorized representative for which 7 days notice shall be given to the supplier.

12.3 TESTS


a) Visual Examination, verification of dimensions, Creepage Distance & marking. b) Mechanical strength test.

c) Porosity test. In case if the facility for conducting any of the above test(s) is not available at the NIGAM’s CTL, the purchaser reserve the right to get such test (s) conducted at any independent NABL Test House.

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In case of failure of any of sample (s) in any of the above tests, the material contained in the lot / sub-lot received to which the samples belong, shall be rejected. The rejected material shall have to be replaced by the supplier free of cost.

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TECHNICAL SPECIFIICATION FOR SUPPLY OF (A) 33 KV CROSS ARM (ANGLE) WITH CLAMP AND TOP HAMPER ,(B)11 KV CROSS ARM (ANGLE) WITH CLAMP AND TOP HAMPER (C 11 KV TOP HAMPER (WITHOUT CLAMP) L.T.CROSS ARM (600 MM) WITH CLAMP AND L.T.CROSS ARM (1200 MM) WITH CLAMP

1. SCOPE

This specification covers fabrication, testing & delivery of fabricated steel items as a complete package, complete in all respect as per GTP/Drawings (to be provided by the purchaser to the successful bidder). The steel sections generally used, tentative unit weight & BOM of fabricated item is enclosed at Schedule-I. The final bill of material for the purpose of payment shall be prepared and submitted by the supplier after approval of model assembly by the purchaser.

2. STANDARDS :


3. MARKING

Each individual structure / section shall carry a code number conforming to component number given to it in the drawing / Bill of material. The code number of approved size shall be stamped with a metal dye of 16 mm size on the member and shall be legible. The name of manufacturers in suitable code and the word “TW” & “IPDS/TN No” shall also be stamped / punched on each individual section with metal dye of not less than 16 mm size.


4. TESTS

Test before dispatch:- The various steel section/structure before dispatch shall be subject to following test as per IS:2062( latest amendment) at the manufacturer’s works Routine test/acceptance test 1. Dimensional checking and visual inspection 2. Weight checking 3. Chemical composition test 4. Mechanical property test

5. SAMPLING:

The inspection shall be carried out on each lot separately. The following number of

pieces selected at random shall be subject to inspection/ testing and checking.

j) Workmanship and dimension checking : 3 % samples from finished item.

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b) Chemical test : One sample of each steel section from the entire lot of material offered for inspection.c) Tensile test : One sample of each steel section from every 50 MT or Part thereof. d) Bend test : One sample of each steel section from every 50 MT or Part thereof.

6. TOLERANCE IN DIMENSIONS : The tolerance(s) shall be permissible as per IS: 1852: (latest amended). Further the following tolerance(s) on fabricated items will also be allowed.



The bidder shall furnish the guaranteed technical particulars of the material as required in the schedule-V by mentioning specific figures therein. Any item of the GTP left unfilled or simply written as per ISS etc. shall be considered as incomplete GTP and such tender is liable to be rejected.


The inspected material should be strictly in accordance to the GTP of the specification otherwise the material shall be treated as rejected and shall not be accepted.

9. WEIGHT



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TECHNICAL SPECIFICATION FOR 110V- 120 AH MAINTENANCE FREE BATTERY

SETS 1.0 SCOPE: The specification covers design, manufacture/ fabrication shop test and offer for inspection, testing and checking before delivery of lead acid maintenance free battery sets along with accessories duly packed suitable for indoor installation at various Grid Sub Station in Jaipur Discom. These equipments are to be completed in every respect, details to the functions designated and to the entire satisfaction of the purchaser. It is required that the supplier in accepting the contract agrees to furnish all apparatus, appliances and material whether specifically mentioned or not but which may be found necessary to complete to perform and testing any of the herein specified equipment(s) for compliance with the requirements implied without extra charges. The erection/ maintenance tools and specific tools if any will also form part of supply. Consideration may be given by the purchaser to alternatives which the supplier considers advisable by reason of his own manufacturing requirement sand experience, provided descriptive matter is submitted pointing out there commended device or arrangements equal to or superior to that required by the accompanying specification with full justification. 2.0 STANDARDS: All material and equipments used for battery set shall comply in all respect with the requirements of the latest edition of the relevant Standards. The tenderer shall quote for sealed maintenance free batteries complying to relevant standard of BS-6290 (Part-IV) 1997 and IEC 896-2/BSEN6089.2, IEEE-1188/1189.Equipment meeting the requirements of any other authoritative standards which ensures a quality equal to or better than that as per the standards mentioned above, shall also be acceptable. Where the equipment conforms to any other standards, salient points of difference between the standards adopted and the specified standards shall be clearly brought out in the tender. 3.0 PRINCIPAL PARAMETERS: The Battery sets to be supplied by the supplier shall meet the requirement of BS- 6290(Part-IV)1997 and IEC 896-2 / BSEN6089.2, IEEE-1188/1189 with latest edition or equivalent and shall be suitable for continuous operation for the climatic conditions specified in the specification. The batteries shall be suitable for float quick charging. The floating voltage shall be regulated to within1% of the normal voltage when the required load is discharged by the battery. Battery sets shall be maintenance free, sealed type in thermoplastic containers with minimum expected life of 15 years. The batteries shall include battery mounting racks and other equipment required to provide a complete operational battery sub system. Battery sets shall be capable of operating at a peak ambient temperature of 50 Deg.C. without degradation of performance and deterioration of expected life. The average ambient temperature shall be 35 Deg.C. The offered battery shall be compact and shall require no regular maintenance. All safety equipment required for installation shall be provided by the manufacturer. Depending upon the situation, the batteries may be required to provide aback-up for 8, 24 or 48 hours. The Bidder shall furnish detail battery sizing calculations along with all arrangements and supporting structures, for each type of DC supply units being proposed, along with the bid. In all cases the battery is normally not allowed to discharge beyond 80% of rated capacity of the battery at 10 hours rate of discharge. The manufacturer supplying the cells/batteries as per this document shall be responsible to replace/repair free of charge, the battery/cell becoming faulty, owing to defective workmanship or material as per the provisions of the bid document.

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All electrical and mechanical equipments shall be designed and manufactured so that no damage will result in transportation, installation and operation of the equipment under the climatic conditions to which it will be subjected. 4.1 MATERIAL AND CONSTRUCTION: 4.2 GENERAL : The storage batteries should be fabricated with Flat pasted type positive plates and Flat pasted type negative plates as per relevant Standards and shall be assembled in hard containers of durable and robust construction. The design of battery shall be as per field proven practices. Partial plating of cells is not permitted. Paralleling of cells externally for enhancement of capacity is not permitted. The cells shall be so designed to be suitable for Horizontal Stacking. 4.2 CONTAINERS : The containers material shall have chemical and electro- chemical compatibility and shall be acid resistant. The material shall meet all the requirements of VRLA batteries and be consistent with the life of battery. The container shall be fire retardant and shall have an Oxygen Index of at least 28%. The porosity of the container shall be such as not to allow any gases to escape except from the regulation valve. The tensile strength of the material of the container shall be such as to handle the internal cell pressure of the cells in the worst working condition. Cell shall not show any deformity or bulge on the sides under all working conditions. The container shall be capable of withstanding the rigours of transport, storage and handling. The containers shall be enclosed in a steel tray. 4.3 CELL COVERS: The cell covers shall be made of suitable material compatible with the container material and permanently sealed with the container. It shall be capable to withstand internal pressure without bulging or cracking. It shall also be fire retardant and shall comply with the provisions set forth in clause of 5.2 above. Fixing of Pressure Regulation Valve & terminal posts in the cover shall be such that the seepage of electrolyte, gas escapes and entry of electro-static spark are prevented. 4.4 PRESSURE REGULATION VALVE : Each cell shall be provided with a pressure regulation valve. The valve shall be self re- sealable and flame retardant. The valve unit shall be such that it cannot be opened without a proper tool. The valve shall be capable to with stand the internal cell pressure specified by the manufacturer. 4.5 TERMINAL POSTS : Both the positive and negative terminals of the cells shall be capable of proper termination and shall ensure its consistency with the life of the battery. The surface of the terminal post extending above the cell cover including bolt hole shall be coated with an acid resistant and corrosion retarding material. Terminal posts or any other metal part which is in contact with the electrolyte shall be made of the same alloy as that of the plates or of a proven material that does not have any harmful effect on cell performance. Both positive and negative posts shall be clearly and unambiguously identifiable. All exposed metal parts(connectors, terminals etc) shall be protected with heat shrinkable silicon sleeves for reducing the environmental impact including a corrosive environment. 4.6 CONNECTORS,NUTS & BOLTS,HEAT SHRINKABLE SLEEVES Where it is not possible to bolt the cell terminals directly to assemble a battery, separate non-corroding lead or copper connectors of suitable size shall be provided to enable connections of the cells. Copper connections shall be suitably lead coated to withstand corrosion due to sulphuric acid at a very high rate of charge or discharge. The area of cross-section of the connectors shall be rated at2 Amp/sq.mm minimum at 6 hour rate of

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discharge. Nuts and bolts for connecting the cells shall be made of copper, brass or stainless steel. Copper or brass nut sand bolts shall be effectively lead coated to prevent corrosion. Stainless steel bolts and nuts can be used without lead coating. All exposed metal parts (connectors, terminals etc.) shall be protected with heat shrinkable silicon sleeves for reducing the environmental impact including a corrosive environment. 4.7 FLAME ARRESTORS : Each cell shall be equipped with a Flame Arrestor to defuse the Hydrogen gases caped during charge and discharge. Material of the flame arrestor shall not affect the performance of the cell. 4.8 SEPARATORS: The separators used shall be glass mat or synthetic material having high acid absorption capability, resistant to sulphuric acid and good insulating properties. The design of separators shall ensure that there is no misalignment during normal operation and handling. 4.9 STAND/SUPPORTING RACK: Necessary stands/supporting racks for fixing and installing the batteries shall be supplied with cell insulators and stand insulators. These racks/stands hall be so designed that cells are placed within easy reach at convenient eight to facilitate easy maintenance. Minimum number of screw should be used primarily for anchoring. The joining of the frames should not leaves crevices and ensure proper and tight fit. Necessary screws etc. should be supplied such that the racks can be fitted without any extra material. Racks shall be constructed so as to permit free access to the floor directly beneath, thus cleaning of both cells and floor is quick and simple task. Racks shall be duly painted with two (2) coats of acid resistance paint and supplied in assembled state with marking .A small quantity of loose paint shall be supplied to enable the purchaser to restore at site for any finish which may got damage during transport. One set of battery testing equipment shall be supplied for each battery sets according to BS-6290 (Part-IV-1997) & IEC-896-2/BSEN 6089.2, IEEE-1188/1189. 4.10 The 110V 120 AH battery shall be suitable for float charge working with 12Amps load. The battery voltage shall not vary beyond 1% of the nominal voltage under float charge conditions and while discharging at 10 Hrs. Rating. The battery will be used for feeding light load in the control room when AC supply fails. The battery should be capable of float/quick charge when AC supply is restored. 5.00 ACCESSORIES: Each battery set shall be supplied complete with all necessary accessories viz. Stand, inter- cell connections, cell insulators, stand insulators, cell No. plates with fixing pins, thermometer, cell testing Voltmeter (3-0-3V) complete with leads, spanners, rubber syringes, rubber gloves and apron etc.

6.1 RATINGS: The rating of battery cells shall be 10 hrs. rating corrected to 27 deg.C as defined under Clause No. 4.1 of IS:1651/1991. The Ampere-hour rating for 110Vbattery banks shall be 120 AH. Each cell will be of 2 volts. Thus the battery bank for 110 V shall consist of 55 cells respectively. 6.2 DESIGNATION: The cell shall be designated by symbol as per relevant Standards.

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6.3 MARKING: The following information shall be indeligibly and durably marked on the outside of the cell.

a) Nominal voltage. b) Manufacturer's type and trade name. c) AH capacity at 10 hour rate. d) Voltage for float operation at 20 deg.C.with tolerance of () 1%. e) Month & Year of manufacture. f) Country of origin.

The cells and batteries may also be marked with the ISI certification mark, if any. 6.4 CAPACITY REQUIREMENT AND DIMENSIONS : When the battery is discharged at 10 hour rate, it shall deliver 80% of C (rated capacity, corrected at 27 Deg Celsius) before any of the cells in the battery bank reaches 1.85 V/cell. The capacity (corrected at 27 Deg. Celcius) shall also not be less than 70% of C and not more than 120% of C before any cell in the battery bank reaches 1.75 V/cell. The battery shall be capable of being recharged from the fully exhausted condition (1.75V/cell) at the specified float voltage. The battery design shall permit the charging of the battery at 2.45V/cell (when two cells shorted). All the cells in a battery shall be designed for continuous float operation at the specified float voltage throughout the life. The battery voltage shall not be less than the following values, when a fully charged battery is put to discharge at C/10 rate.

(a) After Six minute of discharge : 1.98V (b) After Six hours of discharge : 1.92V (c) After 8 hours of discharge : 1.85V (d) After 10 hours of discharge : 1.75V

The bidder shall provide the Tables & Graphs showing relation of the closed circuit voltage, impedance and the residual capacity of each cell in the battery, when it is discharged to the end voltage of 1.75V/cell at C/10 and C/8 rate of discharge. A table and graph showing the relation between the impedance and residual capacity of each cell shall also be provided by the bidder. 6.4 EXPECTED BATTERY LIFE: The battery for float applications shall be capable of giving more than 1200 DOD(up to 80%) cycles at an average temperature of 35 Deg.C Celsius. DOD (Depth of Discharge) is defined as the ratio of the quantity of electricity (in Ampherehour)removed from a cell or battery on discharge to its rated capacity. 6.5 CHEMICAL REQUIREMENTS: Oxygen recombination efficiency of cell/battery shall be higher than 95% for charge current C/10 under normal working conditions. The cell pressure shall be sufficient for 99% gas recombination when working at C/10 rate of charge and ambient temperature of 27Deg. Celsius. Under normal operating conditions grid corrosion shall not be more than 0.05 mm/year. Throughout its life, in the operating condition of C/10 rate of charge and C/8 rate of discharge in average ambient temperature of 35 Deg. Celcius, shedding of active material shall not lead to short circuit. The growth of positive plate shall be less than 8% of the total plate area throughout the specified life. While operating in the normal operating conditions, the cell or battery shall not lead to dry out, throughout the life of the battery. Manufacturer shall supply the necessary data to support the requirement . The battery shall not exhibit thermal runaway while working in

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the average ambient temperature of 35 Deg.C, operating range of 0 to 50 Deg.C and at a charge rate of C/10 and discharge rate of C/8.

7.1 TESTS :

7.2 Type tests: The following tests shall constitute the type tests as per BS 6290(Part-IV)/1997, IEC:896- 2/BSEN6089.2, IEEE-/1189 (latest amended):

a) Capacity Test. b) Mechanical Test c) Short Circuit Test d) Ripple voltage Test. e) Charge retention test. f) Endurance test. g) Suitability for float operation. The above tests shall be performed on the basic cell constituting the 110V-120 AH Battery set. The following shall be carried out as acceptance tests : a) Verification of dimensions and marking and polarity test. b) Capacity test. c) Ampere-hour and Watt-hour efficiency test.

7.3 TYPE TEST CRITERIA : The bidder shall furnish valid & authenticated type test certificates as mentioned at clause No. 7.1 from a Govt./ a Govt. approved/ a Govt. recognized/ NABL Accredited Lab. / ILAC i.e. International Laboratory Accreditation Corporation (in case of foreign Laboratory) or the certificate of type test conducted at manufacturers’ works duly witnessed by representative of any Electricity Board/ Nigam/ Govt. agency/ PGCIL/ NTPC of similar or higher rating of battery sets. Such type test certificates should not be older than seven years as on the date of bid opening. For this purpose, date of conducting type test will be considered. The bidder shall furnish documentary evidence in support of the laboratory whose type test have been furnished, that the said laboratory is a Govt./ a Govt. approved/ a Govt. recognized/ NABL accredited laboratory/ ILAC accredited (in case of foreign laboratory). The type test certificates shall be furnished either in original or copy duly attested by notary.

7.4 TEST AT SITE : The purchaser reserves the right to conduct all the test on the Battery set after arrival at site and the contractor shall guarantee test certificate figures under actual service conditions.

7.5 GUARANTEED TECHNICAL PARTICULARS: The guaranteed technical particulars for battery sets, shall be furnished along with the offer.

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7.6 GUARANTEE PERIOD OF BATTERY SETS :

The guarantee period of each Battery Set along with all accessories shall be for the period of 3 (three) years from the date of receipt of complete set of equipment(s) along with all accessories for one complete set. The supplier shall attend the complaint within 15 days from the date of receipt of complaint and in case complaint is not rectified within 15 days period, penalty@ 0.5% (half percent) per week or part thereof shall be levied upon the supplier till complaint is attended and Battery set is again kept in Circuit

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TECHNICAL SPECIFICATION FOR SUPPLY OF 33 KV (D/C) LATTICE STRUCTURE (42’ LONG) UNGALVANISED ALONGWITH 3 NOS. CROSS ARM (CHANNEL) AND NUTS & BOLTS

1. SCOPE This specification covers fabrication, testing & delivery of fabricated steel items a complete package, complete in all respect as per GTP. 2. STANDARDS : All materials and equipments shall comply in all respect with the requirements of the latest edition of the relevant Indian Standard Specification(s) except as modified in thisspecification. Where the relevant ISS is not available, the material / equipment shouldcomply the latest BSS. All the items should be made / fabricated/tested from steelsections conforming to IS:2062 (latest amended). 3. MATERIAL: The Supplier shall make his own arrangement for the procurement of steel sections before commencement of work. The purchaser shall be at liberty to have samples of steel used, tested / checked in any laboratory at his own cost and reject the supply, if it is found below the required standard. All the material required for fabrication shall be stocked in adequate quantity by the Supplier to ensure the progress of the work is not jeopardized. No relaxation in the delivery time shall be allowed on the pretext of non- availability or short supply of raw materials. 4. WORKMANSHIP: The fabrication shall be done in such a way that there is a good finish of the fabricated structures. The steel structure shall be fabricated accurately adhering to dimensions as per the approved drawings. All the steel sections shall be carefully leveled/ straightened and made true to method which shall not injure the material so that when assembled the adjacent surface are in close contract through out. No rough edges shall be permitted anywhere throughout the work. Holes must be perfectly circular. The tolerance(s) as per drawing/ clause hereunder is permissible. All burrs left by drills or punches shall be removed completely. No bolts holes shall be more than 1.5 mm bigger than the corresponding bolt diameter. In general all fabrication work shall conform to provision of IS-802 (part-I) 1978 latest amended. However the details given in this specification shall prevail in specified items. The overlapping of the M.S.Flat on M.S.angle shall be minimum 30 mm. The holes near the bend lines of absent member, on both sides of bent lines shall be Punched/ drilled after bending and relative position of these holes, shall be maintained with the use of proper templates/jigs and fixtures. Punched holes must be square to the plates and the wall of the holes parallel. The following maximum tolerance of accuracy of punched holes is permissible. a) Holes must be perfectly circular and no tolerance in this respect is permissible. b) The maximum allowable difference in diameter of the holes on the two sides of

plates or angle is 0.8mm i.e. the allowable taper in punched holes should not exceed 0.8 mm on diameter.

c) Holes must be square with the plates or angles and slant holes will not be permitted.

All burrs left by drills or punches shall be removed completely. Drifting or riming to enlarge defective holes shall not be permitted. Minimum edges distance from the centre of any bolt holes shall not be less than what has been indicated hereunder:

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5. MARKING Each individual structure / section shall carry a code number conforming to component number given to it in the drawing / Bill of material. The code number of approved size shall be stamped with a metal die of 16 mm size on the member and shall be legible. The name of manufacturers in suitable code and the word “TW” & “IPDS/TN No” shall also be stamped / punched on each individual section with metal die of not less than 16 mm size. If the above marking is not found on the material received in the stores, the receipted challan shall not be given by the concerned stores. The challan shall only be issued after verification of material by the Store officer. 6. INSPECTION, TESTING & CHECKING : The finished product before acceptance shall be subject to inspection in respect of workmanship, checking of dimension/weight & testing as per requirement of relevantIS:2062 (latest amended), approved drawings and bill of material, at the suppliers works if not supported by test certificates of main producers viz. SAIL/TISCO/RINL. The certificate for type test (chemical composition & mechanical properties test) issued by prime producer(s) shall be furnished along with the inspection call to the SE(TW.),otherwise testing shall be arranged at independent Lab on the cost of supplier. In case bidder use the steel sections manufactured by prime producers then the inspecting officer shall verify and record in the inspection report regarding stamping and mark of prime producers. The certificate(s) in the name of other parties/ sources shall not be accepted and in such cases the tests for chemical and mechanical properties shall have to be arranged in the presence of inspecting officer(s) at recognized lab. The supplier shall present the latest Calibration Certificate(s) of testing instruments/equipments to be used for the testing of the material covered in the purchase order to the authorized inspecting officer/inspecting agency of the purchaser. The testing instruments/ meters/ apparatus etc. should be got calibrated by the supplier from time to time from independent test laboratory/ house having valid accreditation from National/ Accreditation Board for testing and calibrating laboratories for testing equipments/ original manufacturer having trace ability to NABL/NPL or equivalent. The calibration certificate(s) should not in any case be older than one year at the time of presenting the same to the inspecting officer/inspecting agency of the purchaser. The testing instruments/equipments should be duly sealed by the Calibrating agency and be indicated in the calibration certificate(s). The following facilities are to be provided by the supplier at his own cost to the inspecting officer of JVVNL. (a) Suitable accommodation. (b) Local conveyance between arrival point, place of stay, works and departure

point. (c) The supplier shall assist in arranging return ticket and reservation on the request of

the inspecting officer for which the payment shall be made by the inspecting officer. In case of joint inspection, single or shared double room accommodation shall be provided.

7. TESTS Test before dispatch:- The various steel section/structure before dispatch shall be subject to following test as per IS:2062( latest amendment) at the manufacturer’s works Routine test/acceptance test

(i) Visual inspection and checking of Dimension (ii) Weight checking

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(iii) Chemical composition test (iv) Mechanical property test (v) Checking of welding

8. SAMPLING: The inspection shall be carried out on each lot separately. The following number of pieces selected at random shall be subject to inspection/ testing and checking.

a) Workmanship and dimension checking : 3 % samples from finished item. b) Chemical test : One sample of each steel section from the entire lot of material

offered for inspection. c) Tensile test : One sample of each steel section from every 50 MT or Part thereof. d) Bend test : One sample of each steel section from every 50 MT or Part thereof.

9. TOLERANCE IN DIMENSIONS : The tolerance(s) shall be permissible as per IS: 1852-1985 (latest amended). Further the following tolerance(s) on fabricated items will also be allowed.


10. GUARANTEED TECHNICAL PARTICULARS : The bidder shall furnish the guaranteed technical particulars 11. CRITERIA FOR ACCEPTANCE The inspected material should be strictly in accordance to the GTP of the specification otherwise the material shall be treated as rejected and shall not be accepted.

12. WEIGHT The weight of structure shall mean the weight of structures calculated by using standard sectional weights of all steel structural members of the sizes indicated in the fabrication drawings and/or subsequently revised drawings and bill of material without taking into consideration the reduction in weight due to drilling of bolt-holes, skew cuts, chamfering etc. or the increase in weight due to galvanization. The material shall be acceptable if found within permissible tolerance limit i.e. +2% and (-) 4%.

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TECHNICAL SPECIFICATION FOR 30 KV 10 KA HEAVY DUTY SURGEARRESTERS (LIGHTNING ARRESTERS)

1.1 SCOPE:

1.2 This specification provides for the design, engineering, manufacture, assembly,

stage testing, inspection and testing before dispatch, packing, forwarding and delivery of Metal Oxide(gapless) Surge Arresters complete with accessories for 33KV system as specified hereunder:

1.3 It is not the intent to specify completely herein all the details of design and construction of Surge Arresters, However, Surge Arresters shall conform in all respects to the high standard of design and workmanship and be capable of performing in continuous commercial operation up to Bidder's guarantee in a manner acceptable to Purchaser, who will interpret the meanings of drawings and specifications and shall have the power to reject any work or material which in his judgment are not in accordance therewith. The Arresters offered shall be complete with all parts, necessary for their effective and trouble free operation. Such components shall be deemed to be within the scope of supply, irrespective of whether they are specifically brought out in the commercial order or not.

2.1 STANDARDS: 2.2 The Surge Arresters shall conform to the latest editions and amendments available

at the time of supply, of the standards listed hereunder: SlNo. Standard Ref No. Title 1. IEC 99-4 Specification Part.4 for Surge Arresters without gap for AC system. 2 IS:3070(Part-III)Specification for Lightning Arresters for alternating current System 3 IS:2629 Recommended practice for hot dip galvanising of iron andsteel. 4 IS:2633 Method for testing uniformity of coating on Zinc coated articles. 5 IS:5621 Specification for large hollow porcelain for use in electrical installation. 6 IS:2147 Degree of protection provided by enclosures for low voltage switchgear

and control gear. 7. Indian Electricity Rules.1956. Note : i) For the purpose of this specification all technical terms used herein after shall have

the meaning as per IEC specification. ii) For the parameters of the Arrester which are not specified in IEC specification for

Surge Arresters, the provisions of ISS 3070 (Part.III) shall be applicable. 2.3 Surge Arresters meeting with the requirements of other authoritative standards,

which ensure equal or better quality than the standards mentioned above shall also be acceptable. Where the equipment offered by the Bidder conforms to other standards, salient points of difference between the standards adopted and the specified standards shall be clearly brought out in the offer. Four (4)copies of the reference standards in English language shall be furnished along with the offer.

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3.0 PRINCIPAL PARAMETERS : The Surge Arresters offered under this specification shall conform to the parameters given below. ------------------------------------------------------------- S.No. Particulars. System Voltage (KV rms) ----------------------- 30 KV Station type ------------------------------------------------------------- 1. Nominal system voltage 33(kv rms) 2. Highest system voltage 36(kv rms) 3. 1.2/50 micro second impulse voltage withstand level a. Transformer and reactors 170(kvp) b. Other equipment and 170lines (kvp) 4. Minimum prospective 25symmetrical fault current for 1 second at Arresster

location(KA rms) 5. Anticipated levels of temporary over voltage and its duration. a. Voltage(p.u.) 1.5 b. Duration(Seconds) 1/10 6. System frequency(Hz) -------50 Hz plus minus 1.5-- 7. Neutral Grounding --------Effectively Earthed-- 8. Number of Phases --------Three-------------- Note: 1. 1 p.u. = 36 x Root 2 kvp 4.1 GENERAL TECHNICAL REQUIREMENTS : 4.2 The Surge Arresters shall conform to the technical requirements. The energy

handling capability of each rating of Arrester offered, supported by calculations, shall be furnished in the offer.

4.3 The Station Type Surge Arresters shall be fitted with pressure relief devices and arc diverting ports and shall be tested as per the requirements of IEC specification for minimum prospective symmetrical fault

4.4 The grading ring on each complete Arrester for proper stress distribution shall be provided if required for attaining all the relevant technical parameters.

4.5 PROTECTIVE LEVELS : The basic insulation levels and switching impulse withstand levels of the lines and equipment to be protected ". The protective characteristics of the Arresters offered shall be clearly specified in the schedule of guaranteed technical particulars.

4.6 GENERAL REQUIREMENTS : 4.6.1 The materials and components not specifically stated in this specification but which

are necessary for satisfactory operation of the equipment are deemed to be included in the scope of supply unless specifically excluded.

4.6.2 Unless otherwise brought out separately by the Bidder in the schedule of deviations the Surge Arresters offered shall conform to the specification scrupulously. All deviations from the specification shall be brought out in the schedule of deviations. The discrepancies between the specification and the catalogues or literature submitted as part of the offer shall not be considered as valid deviations unless specifically brought out in the schedule of deviations.

4.6.3 Any deviation which has not been specifically brought out in the schedule of deviations of the Bid Proposal Sheets, shall not be given effect to. The deviations

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brought out in the schedule shall be supported by authentic documents, standards and other references.

4.5.4. Each individual unit of Surge Arresters shall be hermetically sealed and fully protected against ingress of moisture. The hermetic seal shall be effective for the entire life time of the Arrester and under the service conditions as specified. The Bidder shall furnish sectional view of the Arrester, showing details of sealing employed.

4.5.5 The bidder shall furnish in the offer, a sectional view of pressure relief device employed in the Station type Surge Arresters offered.

4.5.6 The Surge Arresters shall be suitable for hot line washing. 4. 6 Construction : 4.6.1 All the units of Arresters of same rating shall be interchangeable without adversely

affecting the performance. 4.6.2 The Surge Arresters shall be outdoor and suitable for pedestal/ clamp type

mounting. 4.6.3 All the necessary flanges, bolts, nuts, clamps etc., required for assembly of

complete Arrester with accessories and mounting on support structure to be supplied by the Purchaser shall be included in Bidder's scope of supply.

4.6.4 The drilling details for mounting the Arrester on Purchaser's support shall be supplied by the Supplier.

4.6.5 The minimum permissible separation between the Surge Arrester and any earthed object shall be indicated by the Bidder in his offer.

4.7. PORCELAIN / POLYMERIC HOUSING : 4.7.1 The housing may be of Porcelain or Polymeric. 4.7.2 Where the bidders are quoting for Surge Arresters with Porcelain Housing, all

porcelain housings shall be free from lamination cavities or other flaws affecting the maximum level of mechanical and electrical strengths.

4.7.3 The porcelain shall be well vitrified and nonporous. 4.7.4 The porcelain petticoat shall be preferably of self cleaning type (Aerofoil

design).The details of the porcelain housing such as height, angle of inclination, shape of petticoats, gap between the petticoats, diameter(ID and OD) etc., shall be indicated by the Bidder in his offer in the form of a detailed drawing.

4.7.5 The Arrester housing shall conform to the requirements of IEC specification. 4.8. GALVANISATION, NICKEL PLATING ETC.: 4.8.1. All ferrous parts exposed to atmosphere shall be hot dip galvanised as per

IS:2629 as amended from time to time. Tinned copper/brass lugs shall be used for internal wiring. Screws used for electrical connections shall be either made of brass or nickel plated.

4.8.2. Ground terminal pads and name plate brackets shall be hot dip galvanised. 4.8.3 The material shall be galvanised only after completing all shop operations. 4.9 ACCESSORIES AND FITTINGS : 4.9.1 necessary accessories and earthing connection leads shall be in the Bidder's

scope of supply. 4.9.2 Terminal connector conforming to IS:5561 shall be supplied along with the

arrester. 4.10 The grounding terminal shall be suitable for accommodating Purchaser's

grounding connection to steel earth mat. 4.11. Name Plate :

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The arrester shall be provided with non-corrosive legible name plate indelibly marked with the following information: 1. JVVNL 2. IPDS/TN 3. Manufacturer's name, address, Phone & Fax Number, trade mark and identification

no. of the Arrester being supplied. 4. Rated Voltage. 5. Maximum continuous operating voltage. 6. Type. 7. Rated Frequency. 8. Nominal discharge current. 9. Line discharge class. 10. Pressure relief current in kA rms. 11. B.I.L. of the equipment to be protected. 12. Year of manufacture. 13. Date of dispatch. 14. Date of Expiry of Warranty. 5.0. TESTS : 5.1 TEST BEFORE DESPATCH: The Surge Arrester of various rating and accessories shall be subjected at maker's works before dispatch, to the following tests as per relevant standards. A) ROUTINE TEST ON EACH UNIT AS PER RELEVANT STANDARDS : 1. Measurement of reference voltage. 2. Residual voltage test. 3. Satisfactory absence from partial discharges and contact noises. 4. For arrester units with sealed housing leakage check shall be made on each unit. 5. Current distribution test for multi Column arrester. 5.2 TYPE TESTS : The bidder must furnish type test reports from a Govt. approved / Govt. recognized/ NABL Accredited laboratory / ILAC i.e. International Laboratory Accredited Laboratory (in case of foreign laboratory) of similar rating and design of tendered material/ equipment along with detailed dimensional drawing duly signed &verified by testing agency also showing size & numbers of blocks dimensions contained in the housing along with bid as per the qualification requirement of the Tender Specification. Such type test certificates should not be older than 5 (Five)years as on the date of bid opening. For this purpose date of conducting type test will be considered. The type test certificates should be furnished either in Original or in copy duly Notary attested. 5.2.2 TYPE TESTS SHALL BE CONDUCTED ON ONE UNIT OF EACHRATING AS PER RELEVANT STANDARD.

1. Insulation withstand test. 2. Residual voltage test. 3. Bending test on arrester housing assembly. 4. Long duration current impulse withstand test. 5. Operating duty test. 6. Pressure relief test(Only for station type) 7. Artificial pollution test on porcelain. 8. Partial discharge test. 9. Housed arresters.

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a) Temperature cycle test. b) Porosity test. 10. Galvanising test on exposed ferrous metal parts.

11. Any other type test which are not specified above but covered as per amendment/latest edition of relevant IS/IEC.

5.3 TEST ON BOUGHT OUT ITEMS : Tests are not required to be performed on bought out equipments/items like, Terminal connector etc. at the works of manufacturer. Furnishing Test Certificate of bought out items from the original equipment manufacturers shall be deemed to be satisfactory evidence. Inspection of the tests at Sub-contractors works will be arranged by the supplier whenever required. 5.4 ROUTINE/ACCEPTANCE TESTS : The following tests shall be got conducted in presence of purchaser's representative, as per stipulation of the relevant standards. Acceptance tests whenever possible, shall be conducted on the complete arrester unit. No. of samples to be selected for acceptance tests shall be nearest lower whole number to the cube root of the number of arresters to be supplied. 1. Measurement of power frequency reference voltage on the complete arrester at the

reference current measured at the bottom of the arrester. 2. Lightning Impulse residual voltage. 3. Partial discharge test. 4. Visual inspection & verification of dimension. 5. Special thermal stability test. 6. Galvanising test on Ferrous metal parts. 7. Any other tests as per IS. 5.5 TOLERANCE ON TEST RESULTS : As per relevant standards/specifications. 5.6. CHECKING AT STORES (TEST AT CTL): One out of every 50 Nos. Surge Arresters will be selected for checking for visual, dimensional, weight, marking etc. as per relevant ISS/GTP/approved drawing.

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TECHNICAL SPECIFICATION FOR 9 KV 10 KA HEAVY DUTY SURGEARRESTERS (LIGHTNING ARRESTERS)

1.1 SCOPE: 1.2 This specification provides for the design, engineering, manufacture, assembly,

stage testing, inspection and testing before dispatch, packing, forwarding and delivery of Metal Oxide(gapless) Surge Arresters complete with accessories for 11KV system as specified hereunder:

1.2 It is not the intent to specify completely herein all the details of design and construction of Surge Arresters, However, Surge Arresters shall conform in all respects to the high standard of design and workmanship and be capable of performing in continuous commercial operation up to Bidder's guarantee in a manner acceptable to Purchaser, who will interpret the meanings of drawings and specifications and shall have the power to reject any work or material which in his judgment are not in accordance therewith. The Arresters offered shall be complete with all parts, necessary for their effective and trouble free operation. Such components shall be deemed to be within the scope of supply, irrespective of whether they are specifically brought out in the commercial order or not.

2.1 STANDARDS: 2.2 The Surge Arresters shall conform to the latest editions and amendments available at the time of supply, of the standards listed hereunder: Sl No. Standard Ref No. Title 1. IEC 99-4 Specification Part.4 for Surge Arresters without gap for AC system. 2 IS:3070(Part-III)Specification for Lightning Arresters for alternating current System 3 IS:2629 Recommended practice for hot dip galvanising of iron and steel. 4 IS:2633 Method for testing uniformity of coating on Zinc coated articles. 5 IS:5621 Specification for large hollow porcelain for use in electrical installation. 6 IS:2147 Degree of protection provided by enclosures for low voltage switchgear

and control gear. 7. Indian Electricity Rules.1956. Note : i) For the purpose of this specification all technical terms used herein after shall have

the meaning as per IEC specification. ii) For the parameters of the Arrester which are not specified in IEC specification for

Surge Arresters, the provisions of ISS 3070 (Part.III) shall be applicable. 2.3 Surge Arresters meeting with the requirements of other authoritative standards,

which ensure equal or better quality than the standards mentioned above shall also be acceptable. Where the equipment offered by the Bidder conforms to other standards, salient points of difference between the standards adopted and the specified standards shall be clearly brought out in the offer. Four (4) copies of the reference standards in English language shall be furnishedalong with the offer.

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3.0 PRINCIPAL PARAMETERS : The Surge Arresters offered under this specification shall conform to the parameters given below. ------------------------------------------------------------- S.No. Particulars. System Voltage (KV rms) ----------------------- 9 KV Station type ------------------------------------------------------------- 1. Nominal system voltage 11(kv rms) 2. Highest system voltage 12(kv rms) 3. 1.2/50 micro second impulse voltage withstand level a. Transformer and reactors 75(kvp) b. Other equipment and 75lines (kvp) 4. Minimum prospective 10symmetrical fault current for 1 second at Arresster location(KA rms) 5. Anticipated levels of temporary over voltage and its duration. a. Voltage(p.u.) 1.5 b. Duration(Seconds) 1/10 6. System frequency(Hz) -------50 Hz plus minus 1.5-- 7. Neutral Grounding --------Effectively Earthed-- 8. Number of Phases --------Three-------------- Note: 1. 1 p.u. = 12 x Root 2 kvp/ Root 3

4.1 GENERAL REQUIREMENTS : 4.2 The materials and components not specifically stated in this specification but which

are necessary for satisfactory operation of the equipment are deemed to be included in the scope of supply unless specifically excluded.

4.2 Unless otherwise brought out separately by the Bidder in the schedule of deviations the Surge Arresters offered shall conform to the specifications crapulously. All deviations from the specification shall be brought out in the schedule of deviations. The discrepancies between the specification and the catalogues or literature submitted as part of the offer shall not be considered as valid deviations unless specifically brought out in the schedule of deviations.

4.3 Any deviation which has not been specifically brought out in the schedule of deviations of the Bid Proposal Sheets, shall not be given effect to. The deviations brought out in the schedule shall be supported by authentic documents, standards and other references.

4.4. Each individual unit of Surge Arresters shall be hermetically sealed and fully protected against ingress of moisture. The hermetic seal shall be effective for the entire life time of the Arrester and under the service conditions as specified. The Bidder shall furnish sectional view of the Arrester, showing details of sealing employed.

4.5 The bidder shall furnish in the offer, a sectional view of pressure relief device employed in the Station type Surge Arresters offered.

4.6 The Surge Arresters shall be suitable for hot line washing. 4.7 Construction : 4.7.1 All the units of Arresters of same rating shall be interchangeable without adversely

affecting the performance. 4.7.2 The Surge Arresters shall be outdoor and suitable for pedestal/ clamp type

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mounting. 4.7.3 All the necessary flanges, bolts, nuts, clamps etc., required for assembly of

complete Arrester with accessories and mounting on support structure to be supplied by the Purchaser shall be included in Bidder's scope of supply.

4.7.4 The drilling details for mounting the Arrester on Purchaser's support shall be supplied by the Supplier.

4.7.5 The minimum permissible separation between the Surge Arrester and any earthed object shall be indicated by the Bidder in his offer.

4.8. PORCELAIN / POLYMERIC HOUSING : 4.8.1 The housing may be of Porcelain or Polymeric. 4.8.2 Where the bidders are quoting for Surge Arresters with Porcelain Housing, all

porcelain housings shall be free from lamination cavities or other flaws affecting the maximum level of mechanical and electrical strengths.

4.8.3 The porcelain shall be well vitrified and nonporous. 4.8.4 The creepage distance of the Arrester housing shall be as per Annexure-A. 4.8.5 The porcelain petticoat shall be preferably of self cleaning type (Aerofoil

design).The details of the porcelain housing such as height, angle of inclination, shape of petticoats, gap between the petticoats, diameter(ID and OD) etc., shall be indicated by the Bidder in his offer in the form of a detailed drawing.

4.8.6 The Arrester housing shall conform to the requirements of IEC specification. 4.9. GALVANISATION, NICKEL PLATING ETC.: 4.9.1. All ferrous parts exposed to atmosphere shall be hot dip galvanised as perIS:2629

as amended from time to time. Tinned copper/brass lugs shall be used for internal wiring. Screws used for electrical connections shall be either made of brass or nickel plated.

4.9.2. Ground terminal pads and name plate brackets shall be hot dip galvanised. 4.9.3 The material shall be galvanised only after completing all shop operations. 5.0. ACCESSORIES AND FITTINGS : 5.1 All necessary accessories and earthing connection leads shall be in the Bidder's

scope of supply. 5.2 Terminal connector conforming to IS:5561 shall be supplied along with the

arrester. 5.3 The grounding terminal shall be suitable for accommodating Purchaser's grounding

connection to steel earth mat. 5.4. Name Plate :

The arrester shall be provided with non-corrosive legible name plate indelibly marked with the following information:

1. JVVNL 2. IPDS/TN/ 3. Manufacturer's name, address, Phone & Fax Number, trade mark and identification

no. of the Arrester being supplied. 4. Rated Voltage. 5. Maximum continuous operating voltage. 6. Type. 7. Rated Frequency. 8. Nominal discharge current. 9. Line discharge class. 10. Pressure relief current in kA rms.

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11. B.I.L. of the equipment to be protected. 12. Year of manufacture. 13. Date of dispatch. 14. Date of Expiry of Warranty. 6.0. TESTS : 6.1 TEST BEFORE DESPATCH: The Surge Arrester of various rating and accessories

shall be subjected at maker's works before dispatch, to the following tests as per relevant standards.

A) ROUTINE TEST ON EACH UNIT AS PER RELEVANT STANDARDS : 1. Measurement of reference voltage. 2. Residual voltage test. 3. Satisfactory absence from partial discharges and contact noises. 4. For arrester units with sealed housing leakage check shall be made on each unit. 5. Current distribution test for multi Column arrester.

6.2 TYPE TESTS : The bidder must furnish type test reports from a Govt. approved / Govt. recognized/ NABL Accredited laboratory / ILAC i.e. International Laboratory Accredited Laboratory (in case of foreign laboratory) of similar rating and design of tendered material/ equipment along with detailed dimensional drawing duly signed &verified by testing agency also showing size & numbers of blocks dimensions contained in the housing along with bid as per the qualification requirement of the Tender Specification. Such type test certificates should not be older than 5 (Five)years as on the date of bid opening. For this purpose date of conducting type test will be considered. The type test certificates should be furnished either in Original or in copy duly Notary attested. 6.2.1 TYPE TESTS SHALL BE CONDUCTED ON ONE UNIT OF EACHRATING AS

PER RELEVANT STANDARD. 1. Insulation withstand test. 2. Residual voltage test. 3. Bending test on arrester housing assembly. 4. Long duration current impulse withstand test. 5. Operating duty test. 6. Pressure relief test(Only for station type) 7. Artificial pollution test on porcelain. 8. Partial discharge test. 9. Housed arresters. a) Temperature cycle test. b) Porosity test. 10. Galvanising test on exposed ferrous metal parts. 11. Any other type test which are not specified above but covered as per

amendment/latest edition of relevant IS/IEC. 6.3 TEST ON BOUGHT OUT ITEMS : Tests are not required to be performed on bought out equipments/items like, Terminal connector etc. at the works of manufacturer. Furnishing Test Certificate of bought out items from the original equipment manufacturers shall be deemed to be satisfactory evidence. Inspection of the tests at Sub-contractors works will be arranged by the supplier whenever required.

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6.4 4 ROUTINE/ACCEPTANCE TESTS : The following tests shall be got conducted in presence of purchaser's representative, as per stipulation of the relevant standards. Acceptance tests whenever possible, shall be conducted on the complete arrester unit. No. of samples to be selected for acceptance tests shall be nearest lower whole number to the cube root of the number of arresters to be supplied.

1. Measurement of power frequency reference voltage on the complete arrester at the reference current measured at the bottom of the arrester.

2. Lightning Impulse residual voltage. 3. Partial discharge test. 4. Visual inspection & verification of dimension. 5. Special thermal stability test. 6. Galvanising test on Ferrous metal parts. 7. Any other tests as per IS.

6.5TOLERANCE ON TEST RESULTS : As per relevant standards/specifications. 6.6.CHECKING (TEST AT CTL): One out of every 50 Nos. Surge Arresters will be selected for checking at Store for visual, dimensional, weight, marking etc. as per relevant ISS/GTP/approved drawing.

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Technical specification of 11 kV Drop Out Fuse Cut Outs

1. SCOPE

This specification covers outdoor, open, drop-out expulsion type Fuse Cutouts suitable for installation in 50 Hz, 11 KV distribution system.

2. APPLICATION

The distribution fuse cutouts are intended for use in distribution transformers and have no inherent load break capacity.

3. APPLICABLE STANDARD

Unless otherwise modified in this specification, the cutout shall conform to IS:9385 (Part-I to III) as amended from time to time.

4. RATED VOLTAGE

The rated voltage shall be 12 KV.

5. RATED CURRENT

The rated current shall be 100 A.

6. RATED LIGHTNING IMPULSE WITHSTAND VOLTAGE VALUES FOR THE

FUSE BASE

The rated lightning impulse withstand voltages both for positive and negative polarities shall be as given below:

a) To earth and between poles 75 KV (Peak) b) Across the isolating distance of fuse base 85 KV (Peak)

7. RATED ONE MINUTE POWER FREQUENCY WITHSTAND VOLTAGE (DRY &

WET) VALUES FOR THE FUSE BASE

a) To earth and between poles 28 KV (rms) b) Across the isolating distance 32 KV (rms)

8. TEMPERATURE RISE LIMIT (In Air)

a) Copper contacts silver faced 65oC b) Terminals 50oC c) Metal parts acting as springs. The temp. shall not reach such a value

that elasticity of metal ischanged

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9. RATED BREAKING CAPACITY

The rated breaking capacity shall be 8 KA (Asymmetrical).

10. GENERAL REQUIREMENTS/CONSTRUCTIONAL DETAILS

10.1 The cutouts shall be of single vent type (downward) having a front connected fuse

carrier suitable for angle mounting. 10.2 All ferrous parts shall be hot dip galvanised in accordance with the latest version of

IS:2633. Nuts and bolts shall conform to IS:1364. Spring washers shall be electro- galvanised.

10.3 Typical constructional details of the fuse cutout are shown in Fig. 1

11. FUSE BASE TOP ASSEMBLY

11.1 The top current carrying parts shall be made of a highly conductive copper alloy

and the contact portion shall be silver plated for corrosion resistance and efficient current flow. The contact shall have a socket cavity for latching and holding firmly the fuse carrier until the fault interruption is completed within the fuse.

11.2 The top contact shall be actuated by a strong steel spring which keeps it under

sufficient pressure to maintain a firm contact with the fuse carrier during all operating conditions. The spring shall also provide flexibility and absorbs most of the stresses when the fuse carrier is pushed into the closing position.

11.3 The current carrying parts of the assembly shall be protected from water and dust

formation by a stainless steel top cover.

11.4 The top contact assembly shall have a robust galvanised steel hook to align and guide the fuse carrier into the socket latch even when the fuse carrier is closed at an off-centre angle.

11.5 The top assembly shall have an aluminum alloy terminal connector

11.6 The top assembly shall be robust enough to absorb bulk of the forces during the

fuse carrier closing and opening operations and shall not over-stress the spring contact. It shall also prohibit accidental opening of the fuse carrier due to vibrations or impact.

12. FUSE BASE BOTTOM ASSEMBLY

12.1 The conducting parts shall be made of high strength highly conductive copper

alloy and the contact portion shall be silver plated for corrosion resistance and

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shall provide a low resistance current path from the bottom fuse carrier contacts to the bottom terminal connector.

12.2 The bottom assembly shall have hinge contacts made from highly conductive,

anti-corrosive copper alloy and shall accommodate and make a firm contact with the fuse carrier bottom assembly. The fuse carrier shall be placed easily in or lifted from The hinges without any maneuvering. In addition, the bottom assembly shall perform the following functions :-

i) When opened manually or after fault interruption the fuse carrier shall swing

through 180o to the vertical and its further travel shall be prevented by the fuse base bottom assembly.

ii) The fuse carrier shall be prevented from slipping out of the self locking

hinges during all operating conditions and only when the fuse carrier has reached its fully open position can it be removed from the hinge support.

12.3 The assembly shall have an aluminium alloy terminal connector

13 FUSE CARRIER TOP ASSEMBLY

13.1 The fuse carrier top contact shall have a solid replaceable cap made from highly

conductive, anti-corrosive copper alloy and the contact portion shall be silver plated to provide a low resistance current path from the Fuse Base Top Contact to the Fuse Link. It shall make a firm contact with the button head of the fuse link and shall provide a protective enclosure to the fuse link to check spreading of arc during fault interruptions.

13.2 The fuse carrier shall be provided with a cast bronze opening eye (pull ring)

suitable for operation with a hook stick from the ground level to pull-out or close-in the fuse carrier by manual operation.

14. FUSE CARRIER BOTTOM ASSEMBLY

14.1 The fuse carrier bottom assembly shall be made of bronze castings with silver

plating at the contact points to efficiently transfer current to fuse base. It shall make smooth contact with the fuse base bottom assembly during closing operation.

14.2 The bottom assembly shall have a lifting eye for the hook stick for removing or

replacing the fuse carrier. 14.3 The bottom assembly shall have a suitable ejector which shall perform the

following functions :

i) It shall keep the fuse link in the centre of fuse tube and keep it tensioned under all operating conditions.

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ii) It shall be capable of absorbing the shock when the fuse carrier is pushed into the closed position and shall not allow the fuse link to be damaged. This is specially important when the fuse link is of low-ampere rating.

iii) The ejector at the instant of interruption shall retain the fuse carrier in the

closed position long enough to ensure that the arc is extinguished within the fuse tube thereby excluding the possibility of arcing and subsequent damage at the contact surfaces.

iv) The ejector shall help the fuse link separation after fault interruption, allowing

the fuse carrier to drop out and clearing the pigtail of the blown fuse link through the bore of fuse tube.

15. FUSE BASE (PORCELAIN)

The fuse base shall be a bird-proof, single unit porcelain insulator with a creepage distance (to earth) not less than 320mm. The top and bottom assemblies as also the middle clamping hardwares shall be either embedded in the porcelain insulator with sulphur cement or suitably clamped in position. For embedded components, the pull out strength should be such as to result in breaking of the porcelain before pull out occurs in a test. For porcelain insulators, the beam strength shall not be less than 1000 Kg.

16. FUSE TUBE

The fuse tube shall be made of fibre glass coated with ultraviolet inhibitor on the outer surface and having arc quenching bone fibre liner inside. The tube shall have high bursting strength to sustain high pressure of the gases during fault interruption. The inside diameter of the fuse tube shall be 17.5mm. The

solid cap of the fuse carrier shall clamp the button head of the fuse link, closing the top end of the fuse tube and allowing only the downward venting during fault interruption.

17. TYPE TESTS

The cutout shall be subjected to the following type tests : i) Dielectric tests (rated impulse withstands and rated one minute power frequency

with stand test voltages)

ii) Temperature rise test The above tests shall be carried out in accordance with IS:9385 Part I & II.

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For Porcelain Fuse Base only.

iii) Pull out test for embedded components of the fuse base

iv) Beam strength of porcelain base

18. MOUNTING ARRANGEMENT 18.1 The cutouts shall be provided with a suitable arrangement for mounting these on

75x40mm or 100x50mm channel cross arm in such a way that the centre line of

the fuse base is at an angle of 15o to 20o from the vertical and shall provide the necessary clearances from the support. Mounting arrangement shall be made of high strength galvanised steel flat and shall be robust enough to sustain the various stresses encountered during all operating conditions of the cutout. For more details see enclosed figure 2.

18.2 Strength of the component marked 1 (see figure) shall be determined by

clamping the member with the shorter leg at the top to a rigid support by M-10 carriage bolts. A downward force shall be applied along the axis of M-14 carriage bolt parallel to the longer leg and in the direction of longer leg of the member under test. A load of 50 Kg. shall be applied and then removed to take up any slack in the mounting arrangement before the measurement of position is taken, the permanent set measured at the axis of the M-14 carriage bolt shall not exceed 1.6mm when a load of 425 Kg. is applied and removed.

18.3 The strength of the M-14 bolt shall in no case be less than1900 Kg. and the

strength of M-10 bolts not less than 3500 Kg.

19. TERMINAL CONNECTIONS

The cut-out shall be provided with two aluminium alloy (alloy designation 2280 (A- 11) as per IS:617-1975) terminal connectors at top and bottom of fuse base assemblies to receive aluminium conductors of diameters between 6.3mm to10.05mm. These terminals shall be easily accessible irrespective of the cutout location with respect to the pole. The terminals shall meet the test requirements of REC Construction Standard.

20. INSPECTION

All tests and inspection shall be made at the place of manufacture unless otherwise especially agreed upon by the manufacturer and the purchaser at the time to purchase. The manufacturer shall afford the inspector representing the purchaser all reasonable facilities without charge, to satisfy him that the material is being furnished in accordance with this specification.

The purchaser has the right to have the tests carried out at his own cost by an

independent agency whenever there is dispute regarding the quality of supply.

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Technical Specification for Porcelain Insulators and Insulator Fittings for 33 kV Overhead Power Lines

1. SCOPE

This specification covers the details of the porcelain insulators and insulator fittings for use on 33 KV lines in rural electric sub-transmission systems.

2. APPLICABLE STANDARDS

Unless otherwise stipulated in this Specification, the insulators shall comply with the Indian Standard Specification IS:731-1971 and the insulator fittings with IS:2486 (Pt.I)-1971 and IS:2486 (Pt.II)-1974 or the latest version thereof.

3. INSULATORS

3.1 General Requirements 3.1.1 The porcelain shall be sound, free from defects, thoroughly vitrified and smoothly

glazed.

3.1.2 Unless otherwise specified, the glaze shall be brown in colour. The glaze shall

cover all the porcelain parts of the insulator except those areas which serve as supports during firing or are left unglazed for the purpose of assembly.

3.1.3 The design of the insulator shall be such that stresses due to expansion and

contraction in any part of the insulator shall not lead to deterioration. The porcelain shall not engage directly with hard metal.

3.1.4 Cement used in the construction of the insulator shall not cause fracture by

expansion or loosening by contraction and proper care shall be taken to locate the individual parts correctly during cementing. The cement shall not give rise to chemical reaction with metal fittings, and its thickness shall be as uniform as possible.

3.2 Classification

Only Type ‘B’ insulators as defined in Indian Standards shall be used. The string insulators shall only be of ball and socket type.

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3.3 Basic Insulation Levels 3.3.1 The test voltages of the insulators shall be as under :

Table (Clause 3.3.1)

Highest System Voltage

Visible Discharge

Test

Wet Power

Frequency Withstand

Test

Power Frequency Puncture Withstand

Test

Impulse Voltage Withstand

Test Pin String

Insulator Units

KV (rms) KV (rms) KV (rms)

KV (rms)

KV(rms) KV (Peak)

36 27 75 180 1.3 times the actual dry flas over voltage the Unit.

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3.3.2 In this specification, power frequency voltages are expressed as peak values divided by 2 and impulse voltages are expressed as peak values.

3.3.3 The withstand and flashover voltages are referred to the ‘Reference

Atmospheric Conditions’ as per Indian Standard.

3.4 Mechanical Load

The insulators shall be suitable for the minimum failing loads specified as under :

Pin Insulator Failing loads

Failing Loads

String Insulator Units

Commended Pin Ball Shank Diameter

10 KN 45 KN 16 m

3.5 Creepage Distance

The minimum creepage distance shall be as under :

ghest System Voltage Normal and Moderately

olluted Atmosphere (Total)

ily polluted Atmosphere (Total)

1 2 3

36KV 580mm 840mm

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Note : For insulator used in an approximately vertical position the values given in Col.(2) or (3) shall apply. For insulators used in an approximately horizontal position, the value given in Col.(2) shall apply but the value in Col.(3) may be reduced by as much as 20%.

3.6 Tests :

The insulators shall comply with the following tests as per IS:731-1971 and latest version thereof.

3.6.1 Type Tests

a) Visual examination, b) Verification of dimensions, c) Visible discharge test, d) Impulse voltage withstand test, e) Wet power-frequency voltage withstand test, f) Temperature cycle test, g) Electro-mechanical failing load test h) Mechanical failing load test (for those of Type B string insulator units to

which electro mechanical failing load test (g) is not applicable). i) Twenty four hours mechanical strength test (for string insulators only when

specified by the purchaser. j) Puncture Test k) Porosity test and l) Galvanising test

3.6.2 Acceptance Tests

The test samples after having withstood the routine tests shall be subjected to the following acceptance test in the order indicated below :

a) Verification of dimensions. b) Temperature cycle test c) Twenty four hours mechanical strength test (for string insulator units only

when specified by the purchaser) d) Electro-mechanical failing load test. e) Puncture test. f) Porosity test and g) Galvanising test

3.6.3 Routine Test a) Visual examination. b) Mechanical routine test (for string insulator units only) and

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c) Electrical routine test (for string insulator units only)

3.7 Marking

3.7.1 Each insulator shall be legibly and indelibly marked to show the following:

a) Name or trade mark of the manufacturer b) Month and year of manufacture c) Minimum failing load in Newtons d) Country of the manufacture and e) ISI Certification mark, if any.

3.7.2 Marking on porcelain shall be printed and shall be applied before firing.

3.8 Packing

All insulators (without fittings) shall be packed in wooden crates suitable for easy but rough handling and acceptable for rail transport. Where more than one insulator are packed in a crate, wooden separators shall be fixed between the insulators to keep individual insulators in position without movement within the crate. Disc insulators, however, may be assembled instring and packed inside a crate to prevent movement.

4. INSULATOR FITTINGS

4.1 Pins for Pin Insulators

4.1.1 General Requirements

4.1.1.1 The pin shall be a single piece obtained preferably by the process of forging. It

shall not be made by joining, welding, shrink-fitting or any other process from more than one piece of material. It shall be of good finish, free from flaws and other defects. The finish of the collar shall be such that a sharp angle between the collar and the shank is avoided.

4.1.1.2 All ferrous pins, nuts and washer except those made of stainless steel shall be

galvanised. The threads of nuts shall be cut after galvanising and shall be well oiled and greased.

4.1.2 Type & Dimensions

4.1.2.1 Pins with large steel head Type L300N as per IS:2486 (Pt.II) having stalk

length of 300 mm and shank length of 150 mm with minimum failing load of 10 KN shall be used.

4.1.2.2 The complete details of the pin are given in Fig.1.

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4.1.3 Tests Insulator pins shall comply with the following tests as per IS:2486 (pt.I).

4.1.3.1 Type Tests

a) Visual examination test b) Checking of threads on heads c) Galvanising test and d) Mechanical test

4.1.3.2 Acceptance Tests

a) Checking of threads on heads b) Galvanising test and c) Mechanical test

4.1.3.3 Routine Test

Visual examination 4.2 String Insulator Fittings

4.2.1 General Requirements

4.2.1.1 All forgings and castings shall be of good finish and free of flaws and other

defects. The edges on the outside of fittings, such as at the ball socket and holes, shall be rounded.

4.2.1.2 All parts of different fittings which provide for interconnection shall be

made such that sufficient clearance is provided at the connection point to ensure free movement and suspension of the insulator string assembly. All ball and socket connections shall be free in this manner but care shall be taken that too much clearance between ball and socket is avoided.

4.2.1.3 All ferrous fittings and the parts other than those of stainless steel, shall be

galvanised. Small fittings like spring washers, nuts, etc. may be electro- galvanised.

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4.2.2. Type and Dimensions

4.2.2.1 Only ball and socket type insulator sets shall be used. The

nominal dimensions of the ball and sockets, ball eye and cross- arm straps are given in Fig. 2. An assembly drawing of the complete insulator string is given in Fig. 3.

4.2.2.2 Strain clamps shall be suitable for ACSR conductors

7/3.35 mm2 (50 mm2 Al. area), 7/4.09mm (80mm2 Al. area) and 6/4.72mm + 7/1.57 mm (100 mm2 Al. area). The ultimate strength of clamps shall not be less than 41 KN.

4.2.3 Tests

String insulator fittings shall comply with the following tests as per IS:2486 (Pt.I).

4.2.3.1 Type Tests

a) Slip strength test b) Mechanical test c) Electrical resistance test d) Heating cycle test e) Verification of dimensions f) Galvanising/Electroplating test, and g) Visual examination test

4.2.3.2 Acceptance Tests

a) Verification of dimensions b) Galvanising/Electroplating test, and c) Mechanical tests

4.2.3.3 Routine Tests

a) Visual examination test and b) Routine mechanical test

4.2.4 Marking

4.2.4.1 The caps and clamps shall have marked on them the following :

a) Name or trade mark of the manufacturer and b) Year of manufacture

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4.3 Packing

4.3.1 For packing of GI pins, strain clamps and related hardware, double gunny

bags (or wooden cases, if deemed necessary) shall be employed. The heads and threaded portions of pins and the fittings shall be properly protected against damage. The gross weight of each packing shall not normally exceed 50 Kg. Different fittings shall be packed in different bags or cases and shall be complete with their minor accessories fitted in place. All nuts shall be hand-tightened over the bolts and screwed up to the farthest point.

4.3.2 The packages containing fittings may also be marked with the ISI certification

mark

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TECHNICAL SPCIFICATION FOR L.T.AERIALBUNCHED CABLES

1.SCOPE:Thisspecificationcoverstherequirementofcrosslinkedpolyethyleneinsulatedaluminium cablestwistedoveracentralbarealuminiumalloymessengerwireforuseonL.T.overheadli nesinelectrificationsystem. RATEDVOLTAGE: The rated voltage of the cables shall be 1100Volts.

2. SERVICECONDITIONS:Equipmenttobesuppliedagainstthespecificationshallbesuitableforsatisfactoryconti nuousoperationunder the following tropical conditions.

2.1 Maximum ambient temperature (Degree C) 50 2.2 Maximum temperature in shade(DegreeC).... 45 2.3 Minimum temperature of Air in Shade(DegreeC).. 3.5 2.4 Relative Humidity(Percent) 10to100 2.5 Maximum annual rain fall(mm) 1450 2.6 Maximum wind pressure( Kg/sq.mm.) 150 2.7 Maximum altitude above mean sea level( Metres) 1000 2.8 Isoceraunic level( dayper year) 50 2.9 Siesmiclevel( Horizontal Acceleration) 0.3g 2.10 Ground Temp. 30DegreeC 2.11 Moderately hot and humid tropical climate

Conducive to rust and fungus growth

3. STANDARDS:

APPLICABLESTANDARDS : Unless otherwise specified elsewhere in this specification the rating as well as performance and testing of the L.T.A.B. cables shall conform to the IS: 14255/1995 or the latest revision available at the time of placement of order and bearing ISI mark. In addition the following Standards (or the latest version thereof ) shall be applicable :

i) IS 8130-1984 cross linked polyethylene insulated aluminium cables. ii) IS 398(Part- IV) - 1994Aluminium alloy conductors.

4. GENERALTECHNICAL REQUIREMENTS:- The insulated phase conductors (with additional street lighting conductor, if provided) shall be twisted around the bare aluminium alloy messenger wire, which shall take all the mechanical stress. The messenger wire can also serve as the earth cum neutral wire.

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5. PHASE/NEUTRALCONDUCTORS: The conductors shall be made of aluminium & shall be stranded in construction and shall be insulated with black weather resistant cross linked polyethylene suitable for 1100 Volts insulation. The insulated conductors shall generally conform to the standards (i) and (ii) quoted in clause 3 above. The conductors shall be suitably compacted. The outer diameter shall be within the limit as specified in 5.3 below :

The conductors shall be provided with one, two and three ridges for quick identification. The tensile strength of the aluminium wires used in the conductors shall not be less than 90 N/ sq.mm.

The standard size and technical characteristics of conductors shall be as shown in the following table :

Nominal Sectional Area(sq.

mm)

Diameter of compacted conductor(

mm)

Max.DCre sistanceat 20Deg.(0h

m/km)

Insulation thickness

(mm)

Approx. mass(k g/km)

Minimum No.of

Strands

(1) (2) (3) (4) (5) (6) 16 4.4 1.91 1.0 42 6 35 6.8 0.868 1.0 95 6 50 7.9 0.641 1.2 127 6 70 9.6 0.443 1.4 184 12 95 11.3 0.320 1.4 254 15 120 12.7 0.253 1.6 320 15 150 14.2 0.196 2.1 382 17

NOTE:- (A) The resistance values given in col.3 are the max. Permissible. (B) Tolerance of + 5 % is allowable on diameters shown in Col. 2.

6. MESSENGERWIRE: The bare messenger wire shall be made of aluminium alloy generally conforming to IS - 398 (part - IV) - 1994 or the latest version thereof composed of 7 strands and shall be suitably compacted to have smooth round surface to avoid damage to the insulation of the phase conductors twisted around the messenger. There shall be no joints in any wire of the stranded messenger conductor except those made in the base rod of wires before final drawing. The sizes and other technical characteristics of the messenger wire shall be as given in the following table :

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Nominal Sectional

Area(sq.mm.)

Diameter of compacted

conductor(mm)

Approx Mass (kg/km)

Max.DC resistance at2 0Deg.(0hm/km)

Minimum Tensile

Strength. (KN)

(1) (2) (3) (4) (5) 25 5.8 65 1.380 7.4 35 6.8 95 0.968 10.3 50 8.1 130 0.690 14.7 70 9.6 185 0.493 20.6

95 11.2 210 0.398 26.3 120 13.7 287 0.312 33.2

7.0 CROSSLINKEDPOLYETHYLENEINSULATION:The polyethylene insulation shall generally conform to IS: 14255 / 1995 or the latest version thereof. The following properties shall be guaranteed by the supplier

Melt flow index 0.5 or less

Yield Stress Not less than 8 N/sq.mm

Percentage elongation Not less than 350

Carbon black content Between 2 and 3

Vicat Softening Point Not less than 85 Deg. C

Insulation resistivity:

at 27 Deg.C 1x10 (15) ohm cm (Min)

at 70 Deg. C 1x10 (13) ohm cm (Min)

8.0 COMPOSITION AND DESIGNATION OF FINISHED CABLES: The composition and designation of finished cables are given in the flowing tables:

Sr.No Designation Complete Bunched Cables

Overall dia approx Total mass approx

(mm) (kg/km.) 1. 3x50+16+35 32 640 2. 3x70+16+50 34 890 3. 3x95+16+70 39 1180 4. 3x120+16+95 42 1430 5. 3x150+16+120 49 1905

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Note : - The first part of the designation refers to the number and size of the phase conductor, the middle to the street lighting conductor (where provided) and the last to the bare messenger wire. The sizes shown are the nominal sectional areas.

9.0 TESTS FOR PHASE CONDUCTORS:

9.1 TYPE TESTS:

All the type tests are detailed below in accordance with relevant IS , amended up to date , shall be performed on cable samples drawn by the purchaser. Type tests are required to be carried out from the first lot of supply on a sample of any one size of cable ordered. In case facilities of any of the type test is not available at the works of the supplier, then such type tests shall be carried out by the supplier at an independent recognized laboratory at the cost of supplier. Sample for the type test will be drawn by the purchaser's representative and the type tests will be witnessed by him. Supplier, however, can claim exemption from carrying out type tests as above, provided such type tests were already conducted for the UPPCL in the past within five years and the test certificates thereof submitted to authorities may grant waival from carrying type tests, if the type test certificates are acceptable . In case of other Government recognized laboratories / Test House valid approved Government certificate shall be enclosed along with test certificate.

TYPE TESTS :

a. Conductor Resistance Test ( IS : 8130 )

b. Test for thickness of insulation ( IS : 14255 )

c. Physical tests for polyethylene insulation

( IS : 14255 )

d. Test for bleeding and blooming of pigment

( IS : 14255 )

e. Insulation Resistance Test ( IS : 14255 )

f) High voltage test including water ( IS : 14255 ) immersion test

9.2

All tests as per 9.1 except ( c ) and ( d ) In addition, check of diameter values as per clause 5.5.

10.1 TESTS FOR MESSENGER :

TYPE TESTS :

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a) Breaking load test ( to be made on the finished conductors ) ( IS:398- PART-IV )

b) Elongation test ( IS:398-PART-IV ) c) Resistance test ( IS:398-PART-IV )

ACCEPTANCE TESTS: All tests indicated in clause 10.1 above. In addition, check of diameter values as per clause 6.3

11.0 BENDING TEST ON THE COMPLETE CABLE: The test shall be performed on a sample of complete cable. The sample shall be bent around a test mandrel at room temperature for at least one complete turn. It shall then be unwound and the process shall be repeated after turning the sample around it's axis 180 Deg. The cycle of these operations shall then be repeated twice more. The diameter of the mandrel shall be

10 ( D + d ) Where D = actual diameter of the cable ( i.e. the minimum circumscribing circle diameter ) , in mm d = actual diameter of the conductor, in mm No cracks visible to the naked eye are allowed.

12. PACKING AND MARKING The cables shall be wound non-returnable wooden drums conforming to IS : 1778

/ 1961 or the latest version thereof ( specification for Reels & Drums for bare wire ). The drum shall be marked with the following.

a. Manufacturer's name. b. Trade mark, if any. c. Drum number or identification number. d. Size of conductors. e. Size of messenger f. Voltage grade. g. Number and lengths of pieces of cable in each drum h. Gross mass of the packing. i. Net mass of cable, j. ISI mark.

The drums shall be of such construction as to ensure delivery of conductor in the field free from displacement and damage and should be able to withstand all stresses due to handling and the stringing operation so that cable surface is not dented, scratched or damaged in any way during transport and erection. The cable shall be properly lagged on the drum.

The cable drum should be suitable for wheel mounting.

The mass of finished cable in a drum (without mass of drum ) of various designations shall not exceed by more than 10 % of the actual values.

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The normal length of each cable shall be 500 meters with plus / minus 5 % tolerance. While longer lengths shall be acceptable, shorter lengths not less than 100 meters shall be acceptable to the extent of 5 % of the ordered quantity. 13.0 INSPECTION: All tests and inspection shall be made at the place of manufacture unless otherwise especially agreed upon by the manufacture and purchaser at the time of purchase. The manufacturer shall afford the inspector representing the purchaser all reasonable facilities without charge, to satisfy him that the material is being furnished in accordance with this specification.

14.0 QUALITY ASSURANCE PLAN : A detailed list of bought out items which got into the manufacture of cables should be furnished indicating name of the firms from whom these items are procured. The bidder shall also give the details of quality assurance plan followed by him in respect of the raw materials, in process, final inspection, packing and marking. Company may at it's option order the verification of these plans at manufacturer's works as a pre qualification for technically accepting the bid. During verification if it is found that firm is not meeting with quality assurance plan submitted by the firm, the offer shall be liable for rejection

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TECHNICAL SPECIFICATION ISI MARKED FOUR CORE AND TWO CORE LT XLPE INSULATED AND PVCSHEATHED ARMOURED CABLES.

11.0SCOPE: 1.1 This section provides for manufacture, testing before dispatch, supply and

delivery F.O.R. destination of ISI Marked Four Core & Two Core LT XLPE Insulated and PVC Sheathed Armoured Circular Cables with Aluminium Conductor suitable for working voltage up to & including 1100 Volts & Conforming to IS:7098(Pt.-I)/1988 with latest amendments. The requirement of various sizes of Four Core & Two Core LT XLPE Insulated Armoured Cables shall be as per schedule of requirement annexed with this section at Schedule- I. It may be noted that the requirement indicated in the schedule is tentative and may vary at the time of placement of order. The cables shall be ISI marked.

2. STANDARDS:

Unless otherwise stipulated in this specification the following standards with latest amendments shall be applicable.

i) IS:7098(Pt-.I)/1988 : XLPE Insulated cables for working voltages up to and including 1100 Volts.

ii) IS:8130 : Conductors for insulated cables.

iii) IS:5831 : PVC insulation and sheath of electric cables.

iv) IS:10810 : Methods of test for cables.

v) IS:3975/1979 : Galvanized Steel Wire/Strips.

vi) IS:10418 : Drums for electric cables.

3. GENERAL REQUIREMENT: The LT XLPE Insulated Armoured cables shall conform to IS:7098 (Pt.-I)/1988

with latest amendment and bear BIS certification mark. The material used for construction of the cables shall be of best qualities complying with the requirements of IS:7098(Pt-.I)/1988 and other relevant standards. The cables shall be suitable for outdoor / indoor installation free in air and shall be capable of withstanding the normal stresses associated with transportation, erection, reeling and unreeling operations without getting deformed.

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The cable shall be suitable for use where combination of ambient temperature and temperature rise due to load results in a conductor temperature not exceeding 90 degree C under normal operation and 250 degree C under short circuit condition.

The LT XLPE Insulated Armoured Cable shall be ISI marked. The bidder should

be a manufacturer of tendered item. The offers from Sole Selling Agents / Authorised Dealers shall not be entertained. The bids from the trading firms shall not be considered.

4.0 CONDUCTOR:

The conductor shall be composed of plain aluminium wires complying with IS:8130/1984 with latest amendments.

The bidder must guaranteed the minimum weight of Aluminium in

Kg/Km corresponding to nominal cross sectional area of conductor asmentioned in the G.T.P.

5.0 INSULATION:

Insulation shall be Cross-Linked Polyethylene (XLPE) conforming to the requirements given in Table-I of IS: 7098(Pt.-I)/1988 with latest amendments.

6.0 FILLERS: The filler shall be of vulcanized rubber, un-vulcanized rubber, Thermoplastic material or textile material and shall be provided to fill the gaps between cores.

The filler materials shall be so chosen so as to be compatible with temperature of the cable and shall have no deleterious effect on other components of the cable. These shall not be harder than XLPE and PVC used for insulation and outer sheath respectively.

The Central hole/void, if any, of the cable shall be invariably filled with suitable filler material so that there is no gap in the center.

7.0 ARMOURING : Armouring shall be galvanized round steel wires / Strip.

7. OUTER SHEATH:

The outer sheath shall consist of type ST-2 PVC Compound conforming to the requirements of IS:5831/1984.

construction of the conductor shall be solid for 4Cx6 Sq.mm &

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2Cx4 Sq.mm whereas the conductor shall be stranded for size 4CX10 Sq.mm as per Clause No.8.1 of IS:7098 (Pt-.I) /1988 & relevant clause of IS:8130/1984.

A protective barrier may be applied between the conductor and insulation. Such barriers when used, shall be compatible with insulating material and suitable for the operating temperature of the cable.

8. INSULATION: The conductor (with protective barrier, wherever applied) shall be provided

with Cross-Linked Polyethylene (XLPE) insulation applied by extrusion. The insulation shall be so applied that it fits closely on the conductor and it shall be possible to remove it without damage to the conductor. The thickness and tolerance on thickness of insulation shall be as per Clause No.9.2 of IS:7098(Pt-.I)/1988.

9. CORE IDENTIFICATION: The core shall be identified by different colouring of XLPE insulation as per

Clause No.10.1 of IS:7098(Pt.-I)/ 1988. 10. LAYING UP OF CORES:

The cores shall be laid up together with the suitable right hand lay. The interstices shall be filled with non-hygroscopic material.

11. INNER SHEATH (COMMON COVERING):

The laid up cores shall be provided with an inner sheath applied either by

extrusion or by wrapping. However, application of inner sheath by EXTRUSION shall be preferred. It shall be ensured that it is as circular as possible. The thickness of inner sheath shall be as given in Table-5 of IS:7098(Pt.-I)/1988.

The inner sheath shall be so applied that it fits closely on the laid up cores and it shall be possible to remove it without damage to the insulation.

12 ARMOURING :

Application:- Armouring shall be applied over the inner sheath. The armour Wire / Strip shall be applied as closely as possible.

The direction of lay of armour shall be left hand. A Binder Tape may be provided on the armour.

Type of Armour & Dimension :- The armour shall consist of galvanized round steel wires for cable size 2CX4 Sq.mm, 4Cx6 Sq.mm. & 4Cx10 Sq.mm. whereas it shall consist of galvanized steel strip for remaining sizes with the dimensions as specified in Table-6 of IS:7098(Pt-.I)/1988.

Joints:- The joints in the armour Wire / Strips shall be made by brazing or

welding and the surface irregularities shall be removed. A joint in any strips shall be

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at least 300 mm. from the nearest joint in any other armour strip in the completed cable.

13 OUTER SHEATH:

The outer sheath shall be applied by extrusion over armouring. The colour of the outer sheath shall be black. The minimum thickness of PVC outer sheath shall not fall below the nominal thickness ( ts ) specified in Table-8 of IS:7098(pt.I/1988.

14. TESTS AND TEST CERTIFICATES:

The cables should meet the requirement of all tests including optional tests as specified at Clause No.15.4 of IS:7098(Pt.1)/1988.

The following shall constitute Routine Test: 6.1.1 Conductor resistance test. 6.1.2 High Voltage test.

The following shall constitute Acceptance Tests:

i) Tensile test (for Aluminium). ii) Wrapping test (for Aluminium). iii) Conductor resistance test. iv) Test for thickness of Insulation & Sheath. v) Hot Set Test for Insulation.

vi) Tensile strength & elongation at break of insulation & sheath.

vii) Insulation resistance (Volume Resistivity)test. viii) High Voltage test. ix) Test for Armour:

a) Verification of Dimension of Wire / Strip. b) Tensile Strength & elongation at break. c) Uniformity of Zinc Coating. d) Weight of Zinc Coating. e) Winding Test on Armour. f) Resistivity Test on Armour.

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The following shall constitute Optional Tests:

i) Cold Bend Test for outer sheath. ii) Cold Impact Test for outer heath.

The following shall constitute Type Tests:


i) Tensile test (for aluminium) ii) Wrapping test (for aluminium)

iii) Conductor resistance test. b) Test for Armouring Wire / Strip. c) Tests for thickness of insulation and sheath. d) Physical tests for insulation:

i) Tensile strength and elongation at break. ii) Ageing in air oven.

iii) Hot Set test. iv) Shrinkage Test v) Water Absorption (Gravimetric).

e) Physical tests for Outer Sheath:


iii) Loss of mass in air oven. iv) Shrinkage Test. v) Hot Deformation Test.

vi) Heat Shock Test. vii) Thermal Stability.

f) Insulation resistance (Volume Resistivity test) g) High voltage test. h) Flammability test. i) Any other test as per relevant ISS.

TYPE TESTS : The material offered, shall be fully type tested as per relevant standard of specification of IS:7098 (Part.1/1988) amended up to date. The bidder must furnish type test reports of similar rating & design of material

The bidder must also clearly indicate various testing facilities available at their works for testing the material as per relevant standards. In case of otherwise particulars of the place where such testing in proposed to be conducted during the course of inspection shall be indicated with the offer. However, the purchaser reserves the right to demand repetition of same or all the type tests in presence of purchaser’s representative.

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The bidding firms (manufacturers) must have valid ISI license for the offered cable. The bidder shall furnish the details of ISI License granted to them.

15. INSPECTION (TEST BEFORE DISPATCH):

The inspection may be carried out by the purchaser at any stage of manufacturer. Acceptance of any equipment / material under this specification by the purchaser shall not relieve the supplier of his obligation of furnishing equipment in accordance with the specification and shall not prevent subsequent rejection if the equipment/material is found to be defective.

The supplier shall keep the purchaser informed in advance about the manufacturing program so that arrangement can be made for inspection.

The acceptance tests as per IS:7098(Pt.I)/1988 shall also be conducted by the manufacturer before dispatch in the presence of our Representative/Inspecting Officer along with verification of lengths & weight and checking the manufacturing defects, if any of samples coils. The mass of Aluminium, XLPE, PVC & Filler in sample coils shall also be verified by the Inspecting Officer(s).

Cold bend/ cold impact test (IS:5831/1984) shall constitute the optional tests and shall be conducted on first lot and any from other lot of the offered cables of each size as per Clause No.15.4 of IS:7098(Pt-.I)/1988.

• The purchaser reserves the right to insist or witnessing the acceptance/routine tests of the bought out items.

The bidder shall furnish Packing list mentioning serial Nos. of Drums, length in each drum, gross weight of drum without lagging alongwith inspection offer duly signed by the authorized representative of the firm. The purchaser reserves the rights to insist for witnessing the acceptance / routine tests of the bought out items.

At least 5% of total numbers of drums subject to minimum of 2 in any lot put up for inspection shall be selected at random to ascertain the length/ workmanship of cable by the following method :

“At the works of the manufacturer, the cable shall be transferred from one drum to another for checking any manufacturing defects in the cable drums selected for conducting acceptance tests, at the same time measuring its length with the help of the graduated pulley & cyclometer. The difference in the average length thus obtained from the declared length by the supplier in the packing list shall be applied to all the drums if the cable is found short during checking the sample lot(s)”. The supplier shall present the latest Calibration Certificate(s) of testing instruments / equipments to be used for the testing of the material covered in the Purchase Order to the authorized inspecting officer/ inspecting agency of the purchaser. The testing

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instruments/ meters/ apparatus etc. should be got calibrated by the supplier from time to time from Govt. Laboratory or any independent test laboratory/house having valid accreditation from National Accreditation Board for Testing and Calibrating Laboratories for the testing equipments / original manufacturer having trace ability to NABL/NPL or equivalent.

The calibration certificate(s) should not in any case be older than one year at the time of presenting the same to the inspecting officer/ inspecting agency of the purchaser. The testing instruments/ equipments should be duly sealed by the Calibrating Agency and mention thereof shall be indicated in the calibration certificate(s).

16. TEST CHECKING OF MATERIAL: i) Sample drums from the material received in Nigam shall be selected

for testing at CTL as per sampling plan given hereunder in presence of firm’s representative.



iii) The tests in the Nigam Testing laboratory (CTL) shall be conducted in the presence of representative of supplier for which a 7 days notice shall be issued through Fax / Speed Post stating Date & Time to the firm, so that supplier can depute their representative to witness the test . In case the supplier or his representative does not turn up the testing shall be proceeded & completed. The payment shall be released only after receipt of successful test reports for the samples selected at purchaser’s stores for mandatory test checking on the samples to be selected from material received at Nigam’s stores by officers to be nominated by Circle SE’s / SE (I&S) for testing at CTL.

17. SAMPLING: One number Drum out of each lot / sub-lot of 25 Nos. Drums or part thereof for

the material received in Nigam. i) TESTS: The following tests shall be carried out as per relevant clause of latest IS on each selected drum by drawing sample of 10 Mtr. at CTL from random distance during re-winding:

a) Rewinding test (Measurement of Length) & Checking of Manufacturing defects.

b) Measurement of Resistance of conductor. c) Tensile strength & Elongation at Break Test for Insulation & Sheath d) Test for Thickness of Insulation & Sheath e) Hot Set Test f) Test for Armour:

i) Verification of Dimension of Wire / Strip. ii) Tensile Strength & elongation at break.

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iii) Uniformity of Zinc Coating. iv) Weight of Zinc Coating. v) Winding Test on Armour. vi) Resistivity Test on Armour.

g) Verification of Marking

In addition to above tests remaining acceptance tests as per relevant IS shall also be conducted at CTL provided the testing facility is available at CTL for these tests time to time. Only those tests shall be conducted for which testing facilities are available in NIGAM’s Lab.

ii) CRITERIA FOR ACCEPTANCE:

h) If the measured conductor resistance of the sample(s) exceeds beyond 2% as per the resistance specified in the contract, the material shall be rejected and the same shall have be replaced by the supplier.

i) If the measured conductor resistance of the sample(s) exceeds the value specified in the contract but does not exceed by more than 2% of the resistance value specified in the contract, the material pertaining to the relevant lot / sub-lot to shall be accepted with a deduction @ 1.5% of the cost of cable for increase in resistance for every 1% or part thereof.

j) If the sample(s) fails in any other test, the material contained in the pertinent lot/sub-lot shall be rejected and shall have to be replaced by the supplier.

k) If the contractor / supplier fails to lift the material declared rejected or any part thereof from the consignee within a period of 15 days from the date of dispatch of information from the purchaser, the purchaser shall be entitled to effect recovery along with other actions as per Clause No. 1.62 of Section-II (General Condition of Contract).

l) The results of measurement of length test shall be made applicable to

all drums contained in each lot / sub lot by making deduction of less length of cable in a Sample Drum.

18. TEST CHARGES :

All test charges incurred towards test checking of the material received in our stores shall be borne by the NIGAM.

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19. IDENTIFICATION: i ) The manufacturer shall be identified through-out the length of cable

as per Clause No.17.1 of IS:7098(Pt-I)/ 1988. In order to distinguish these electric cables from telephone

cables the word ÈLECTRIC' shall be indicated, printed or embossed throughout the length of the cable on outer sheath.

The cable code shall be used as per Clause No.17.3 of IS:7098(Pt-.I)/1988.

The cable shall also be required to be embossed with the word ` Name of Manufacturer or trade name, Cable code, Voltage Grade, NAME OF DISCOM / TW/TN-/IPDS/ size of cable & year of manufacture' at every meter length for which no extra charges shall be paid. The cable should be ISI marked & same should be embossed on the outer sheath of every meter of length of cable.

20. MARKING:

The progressive length of cable shall be marked on the outer sheath of every meter length of cable.

21. PACKING AND MARKING:

The cables shall be wound on non-returnable wooden drums conforming to IS:10418/1982 of suitable size and packed. The ends of the cable shall be sealed by means of non-hygroscopic sealing material. Only one cable length shall be supplied on a drum. The shaft diameter of Drum shall be as per relevant ISS but not less than 50 mm. The cable can also be supplied on M-Steel Drums as per relevant ISS as applicable.

The cable shall carry the following information stenciled / painted on the

drum :

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i) Manufactuer's name, Brand name or trade mark. ii) Type of cable and voltage grade. iii) Number of Cores. iv) Nominal Cross-sectional area of the conductor. v) Cable Code.

vi) Length of cable on the drum. vii) Approximate gross weight.

viii) Year of manufacture. ix) BIS Certification mark. x) Name of the Consignee and full destination.

xi) IPDS/ TW/TN no. xii) The word SUITABLE FOR OUTDOOR USE &

LOW TEMPERATURE CONDITIONS.

22. STANDARD LENGTH:

The cables shall be supplied in the standard length of 1000 Meters for size 4Cx10 Sq. mm, 4Cx6Sq. mm & 2CX4 Sq.mm.

22.1 A tolerance (+/-) 5% shall be allowed in standard length

22.2 Only one cable length shall be acceptable by non-standard length measuring not less than 50% of standard length to complete the ordered quantity in each size.

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TECHNICAL SPECIFICATION FOR 12 KV OUTDOOR VACUUM CIRCUIT BREAKER KIOSKS.

1.0 SCOPE

This specification is intended to cover the design manufacture, assembly, testing at manufacturer's works, supply, delivery of 12 kV Vacuum Circuit breaker Kiosks with current transformers, Potential transformers, protection relays, metering instruments etc. Complete with all accessories.

1.1 It is not the intent to specify completely herein all details of the design and

construction of equipments. However, the equipment shall conform in all respects to high standards of engineering, design and workmanship and shall be capable of performing in continuous commercial operation upto the Bidder's guarantee in a manner acceptable to the Purchaser, who will interpret the meanings of drawings and specifications and shall have the power to reject any work or material which in his judgment is not in accordance therewith. The offered equipment shall be complete with all components necessary for its effective and trouble free operation along with associated equipments, interlocks, protection schemes etc. Such components shall be deemed to be within the scope of supply, irrespective of whether those are specially brought out in this specification and/or the commercial order or not.

2.0 STANDARDS

The 12 KV vacuum circuit breaker Kiosks shall conform to latest revisions with amendments of standards as under unless specified otherwise. Equipment meeting any other authoritative standard which ensure equal or better quality than the standard mentioned above will also be acceptable. In such cases a copy of standard (English version) adopted, should be enclosed with the tender.

IEC62271/100-200 High Voltage Switchgear & Control gears. IS:13118/IS-3427 Circuit Breaker/ metal enclosed Switchgear

and control gear. IS: 3156 Voltage transformers.IS: 2705 Current transformers.IS: 3231 Electrical Relays for power system.IS:1248 Meters and InstrumentsIS:14697-1999 Specification for AC static transformer operated watt hour

and VAR hour meters class 0.2 S & 0.5 S.

IEC-62053-22-2003 IEC-62052-11-2003

Specification for AC Static Watt hour Meters, class 0.2 S &0.5 S.

CBIP Technical Report No.88 revised July, 1996 read with amendment issued (April,99, September,99 and also any other amendment thereafter).

Specification for AC Static Electrical Energy Meter.

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3.1 CLIMATIC CONDITIONS:

Equipment to be supplied against this specification shall be suitable for satisfactory continuous operation under the following tropical conditions :-

i) Peak ambient air temperature 50 DEG C in shade.

ii) Minimum ambient air temperature (-) 5 DEG C in shade

iii) Maximum relative humidity. 95 %

iv) Minimun relative humidity 10 %

v)Dust storms are liable to occur from the period March to July

vi) Height above mean sea level less than 1000M vii) Average number of thunder 40 DAYS

storms days per annum.

viii) Average annual rainfall 10-100 cm (Depending on area)

ix) Number of months of tropical 4 monsoon conditions p.a.

4.0 PRINCIPAL PARAMETERS OF CIRCUIT BREAKERS

4.1 TYPE AND RATING 12 kV

4.1.1 Type Vacuum circuit breaker

4.1.2 Service Outdoor

4.1.3 Pole 3

4.1.4 Rated voltage 11/12 kV (nominal/max.)

4.1.5 Rated frequency 50 HZ

4.1.6 System Neutral Effectively earthing grounded.

4.1.7 INSULTATION LEVEL

4.1.7.1 Impulse withstand 75 kVp

4.1.7.2 One minute power As per relevant standards.

frequency withstand voltage.

4.1.8 Rated Current

o

4.1.8.1 Continuous at 50 C. 630 A

4.1.8.2 Short time current 16 kA for 3 Sec.

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4.1.9 Rated Breaking Capacity

4.1.9.1 Symmeterical 16 kA

4.1.9.2 Asymmeterical As per relevant standard

4.1.10 Rated making capacity 2.50X16 KA

4.1.11 Rated short time with- 16 KA stand current 3 secs.

4.1.12 Total break time 3 cycles(Max.)

Closing time 4 cycles (Max.)

4.1.13 Creepage distance 300 mm or more

4.1.14 Protection class of kiosk IP-55 as per

IEC 529

4.1.15 Operating duty For gang operation O-0.3 Sec-CO-3min-CO

4.1.16 Operating Mechanism motor operated spring

charged closing mechanism or Magnetic Actuator.

4.1.17 Spring charging Motor 220V-240V

4.1.17.1 Heater/Lamp/Socket. 240V AC

4.1.18 Terminal Connector

4.1.18.1 Type Bimetallic

clamp type/ Al. alloy.

4.1.18.2 Suitable for 10% Panther and 90%

ACSR conductor Dog Conductor

4.2 System details

4.2.1 H.V. System Voltage (Nominal/Max.) 11/12 kV

Phases 3

System Neutral Effectively earthed.

Fault level 16 KA r.m.s.

Symmetrical

4.2.2 Auxiliary power Supply

4.2.2.1 A.C. Supply 1. 415 volts 3 ph 4 W 50 Hz 2. 240V 1 Ph 2 W 50 Hz

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5. GENERAL TECHNICAL REQUIREMENTS:- 5.1 DESIGN CRITERIA

The bidder shall quote 12 KV Outdoor VCB Kiosks conforming to M-2 class only. The equipment will be used in high voltage system having characteristics as listed in the specification. The equipment will be installed outdoor in a hot, humid and tropical atmosphere. All equipment, accessories and wiring shall have tropical protection, involving special treatment of metal and insulation against fungus, insects and corrosion.

The maximum temperature in any part of the equipment at specified rating shall not exceed the permissible limits as stipulated in the relevant standards.

The equipment shall be capable of withstanding the dynamic and thermal stresses of listed short circuit current without any damage or deterioration.


The cowling provision shall be provided on the roof of 12 KV outdoor VCB Kiosk to avoid direct inception of water at any joint.

5.2 SPECIFIC REQUIREMENTS

5.2.1 The vacuum circuit breaker kiosk shall be for outdoor installation. The duty of the

circuit breaker shall involve satisfactory interruption of short circuit currents as listed in the specification. The breaker shall be capable of interruption of low reactive current (lagging/leading) without undue over voltage.

5.2.2 CONSTRUCTIONAL FEATURE

5.2.2.1

a) The circuit breakers shall be triple pole horizontal fixed type enclosed in Kiosk of CRCA sheet steel of 3 mm thickness for load bearing members and 2 mm thickness for non-load bearing members and shall comply with latest edition of IS:13118/3427/IEC-56. The Kiosk shall be vermin proof and dust tight. The switchgears and Control gears shall be complete with all necessary supporting frame works, Nuts and bolts etc. for securing the same to the floor. The operating mechanism shall operate (close/open) all the three phases simultaneously. The operating mechanism links etc. should be accessible for maintenance. The circuit breakers and its operating mechanism shall be fully interlocked to prevent mal-operation. All the breakers shall be supplied with necessary clamps and connectors suitable for appropriate current ratings. Rigid type bimetallic/Al.alloy terminal connectors of 630 Amps.

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current rating form part of supply. Suitable arrangement of earthing the switchgears shall be provided. All the connecting bus bars shall be made of copper.

b) Hinges of door shall be concealed type to avoid rusting and obstructive opening of the door.

c) The quality of welding shall be good and there should not be any lumps and splatters on the panel.

d) All the connecting bus bar and current carrying parts shall be made of copper. e) All the gasket shall be of chemically treated neoprene. f) Hole & Pin locking (Check nut) arrangement should also be provided while fixing the

vacuum interrupter at bottom side.

5.2.2.2 Switchgear (Vacuum Circuit breakers etc.)and control gear (CTs.,PTs, relays etc.)shall be mounted on the same Kiosk. Bus bars shall be air insulated with PVC insulation/sleeves on electrostatic powder coating. The bus bars should be of electrolytic copper with permissible limits of current density. Size of the bus bars and current density should be specified in the tender. The bus bars conductor shall conform to Indian standard 8084 and 3427 and shall be rated for 630 A,STC 16 KA for 3 sec.

5.2.2.3 All the meters, instruments, relays etc. shall be mounted on the switchgear

kiosk. The outdoor circuit breakers Kiosk shall be suitable for AC shunt tripping arrangement.

5.2.2.4 The Kiosk shall have an arrangement for emergency shunt tripping from

remote place in addition to arrangement for local emergency tripping(Mechanical). The kiosk shall also have a system to check the "Trip circuit healthy check" in all the three phases. Necessary trip and closing coils shall be provided for operation of the breakers.

5.2.2.5 All the six terminals shall be brought out through appropriate class

bushings. 5.2.2.6 The arcing contacts shall be made of homogeneous special alloy so that

surge voltage are reduced to negligible level & multiple reignition is eliminated.

5.2.2.7 The circuit breaker kiosk shall be electrically and mechanically trip free

under various conditions. 5.2.2.8 The provision shall be kept on the kiosk roof and roof bushing assembly to adopt

arcing horns. 5.2.2.9 The lifting arrangement shall not cause any effective loss of creepage distance/ phase

to earth clearances as specified in the ISS/IEC.

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5.2.3 MAIN CONTACTS

The main contacts shall have adequate area and contact pressure for carrying rated continuous and short time current without excessive heating liable to cause pitting and welding.

The breakers may be provided with silver plated contacts, if necessary, to meet the requirement of IS:13118/IEC56 where higher temperature rise is permitted with silver plated contacts. The quantity of silver facing shall be such that after carrying out one tenth of total number of operations specified for mechanical endurance tests, there is still continuous layer of silver on contacts.

5.2.4 NUMBER & TYPE OF SPARE, AUXILIARY CONTACTS/ SWITCHES :

Adequate number of spare auxiliary switches/contacts both of normally open & normally close type but not less than four each shall be provided on the circuit breaker for use in the indication and controlling scheme of circuit breakers.

5.2.5 INTERLOCK

All electrical and mechanical interlocks which are necessary for safe and satisfactory operation of the circuit breaker shall be provided .

5.2.6 BUSHINGS FOR CIRCUIT BRAKER KIOSK

a) The out door circuit breakers shall be metal enclosed fitted with weather proof/

suitable type bushing conforming to IS:2099 and shall be designed to have the necessary mechanical strength and rigidity required and shall be free from objectionable interference and external and internal corona. The porcelain shall be of the wet process type, homogeneous, free from laminations and cavities or other flaws which could effect its chemical & mechanical strength and shall not be injuriously stressed by temperature change. The porcelain shall be thoroughly vitrified tough and impervious to moisture and shall be evenly glazed. The glazing shall be free from blisters or burrs. The bushing shall be designed manufactured & tested in accordance with latest edition of IS:2099. The type and characteristic data bushing shall be clearly specified.

b) The bushing shall not be subjected to direct point loading. They shall be provided with neck

around clamps for evenly distributed pressure. c) The bushing shall be mounted using suitable clamps and gasket arrangement to provide required

degree of protection. d) The bushing assembly shall be provided with lock nut and check nut which will be non-magnetic

and non-corrosive.

5.2.7 OPERATING MECHANISM

Characteristics of Operating mechanism of circuit breaker and associated equipments :

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Method of operation: The circuit breaker shall be equipped with power operated mechanism to operate all three phases simultaneously using 220/240 V AC Motor operated spring closing mechanism or magnetic actuator type. It shall be electrically & mechanically trip free under various conditions. Kiosk shall also be provided with hand operated spring charging closing mechanism. Operation counter and mechanically ON-OFF indicator shall be provided.

5.2.8 VACUUM CIRCUIT BREAKER

The three phase vacuum circuit breaker will have three vacuum interrupters (one interrupter per phase) mounted on same carriage. The interrupters shall be air insulated with epoxy resin / insulated phase barriers. Each interrupter shall have fixed and moving contacts in sealed envelops having vacuum below 10-6

torr. The metallic bellow shall permit axial movement of moving contact and act as vacuum seal. The contacts shall have requisite mechanical strength and good electrical and thermal conductivity and shall be made of copper chromium alloy. Complete literature of vacuum bottles shall be furnished with the tender.

In order to have safe operation under fetal conditions, the vacuum interrupter should be housed in epoxy pole unit and make of Vacuum Interrupter will be as “BEL, CGL, SIEMENS, ABB, ALSTOM/AREVA/MEGAWIN”.

Any other equivalent make of V.I. shall also be acceptable subject to prior approval of S.E. (TW), JVVNL, Jaipur.

5.2.9 VOLTAGE TRANSFORMERS

i) Highest equipment voltage : 12 KV ii) No. of phases. : 3 Nos. single phase VTsiii) Insulation level. a) Impulse withstand voltage : 75 KVP

b) One minute power frequencywithstand voltage on : i) Primary winding : As per relevant standard.

ii) Secondary winding : 2 KV rms iv) Frequency. : 50 Hz. v) Transformation ratio. : 11000/110 V vi) Rated output. : 100VA/Phase vii) Accuracy class. : 0.5 viii) Rated voltage factor. : 1.2 continuous &

1.5 for 30 sec. ix) Type of insulation : Resin cast.

VTs, shall be provided with HRC type fuses on the secondary side. The VT fuses on primary side shall also be provided with all safety precautions. One of the secondary terminals of the VTs, shall be solidly earthed. Three numbers single phase voltage transformer of this rated output will be required for each circuit breaker kiosk. Voltage transformers shall be fixed type and shall be suitable for single phasing.

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5.2.10 CURRENT TRANSFORMERS

i) Rated voltage. : 12 KV

ii) Insulation level.

a) Impulse withstand voltage : 75 KVP

b) One minute power frequency withstand voltage on :

i) Primary winding : As per relevant standard.

ii) Secondary winding : 2 KV rms

iii) Frequency. : 50 Hz.

iv) Rated continuous thermal current: 120% of rated primary current

v) Short time thermal rating and its duration. : 16 KA for 3 sec.

vi) Transformation ratio of : Core-I Core.II CTs 400-200-100/5-5A ---------------- a) Rated output 15 VA 15 VA b) Class of accuracy 5 P 0.5S c) Accuracy limit factor. 15 - d) Purpose Relaying Metering

vii) Max.instrument security : - 5 factor.

12 KV current transformers shall be single phase. The core shall be of grade non ageing laminated silicon steel of low hysteresis loss and high permeability to ensure high accuracy at both normal and fault current.

5.2.11 The rating of secondary winding shall be 5 Amps. Required transformers ratio can

be achieved in any manner, However, the current transformers will have to satisfy the requirement of rated VA burden, Class of accuracy , accuracy limit factor and short time thermal rating as have been specified above at all transformation ratio.

The rating of current transformers of all classes regarding ratio error, knee point voltage, resistance of secondary winding etc. shall have to be co-ordinate with the requirement of protective relays and protection scheme without any extra cost.

5.2.12 The tenderer shall also furnish along with the tender, complete general

arrangement, schematic and outline diagrams indicating the mounting arrangement and position of current transformers, potential transformer, terminal block etc. Type of current transformers and potential transformers employed shall also be clearly stated.

5.2.13 INDICATING AND INTERGRATING METERS/INSTRUMENTS:

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All indicating instruments shall be of switch board type, back connected suitable for flush mounting and provided with dust and vermin proof cases for tropical use and finished in suitable colour. All instruments shall have practical laboratory means of adjustment of accuracy. The limits of errors for ammeters/voltmeter shall be permissible for class 1.5 instruments as per IS:1248. The ammeters and voltmeters shall be suitable scaled to indicate the current for all the ratings of current/voltage transformers. A phase selector switch with four/six positions shall be used to measure the current/voltage of each phase. The meter shall be located at eye level to facilitate observation of readings correctly.

Any alarm scheme shall have both audio-visual annunciations in redundancy of each other and appropriate accept and reset push buttons shall be part of alarm scheme.

5.2.14 RELAYS :

The circuit breaker shall be fitted with numerical relay having shunt trip coil for operation on 3 over current & one earth fault element. The numerical relay to be provided with the 12 KV Outdoor VCB Kiosk, should be so designed so as to operate/ trip on earth fault as well as on over current faults but should not operate on unbalance load conditions during single phasing (which can be achieved through residual voltage control or otherwise).

The circuit breaker shall have suitable arrangement for power supply of relay and breaker operation through shunt trip coil using power pack. The power pack should be suitable for 6 Nos. closing/ tripping operations and for future remote communication as well as breaker testing during long time power failure. The output voltage may be as per manufacturer’s design. The charging of Power pack shall be through 230 V A.C. supply available at Sub-Station.

The make, model No., type and Technical specification of the relay as well as power pack are required to be mentioned in the bid.

The Relay & Power Pack arrangement system should be warranted for 5 years (in line with warranty of breaker).

The numerical relays shall have following features:-

f. Self Diagnosis

g. Minimum last five abnormal events recording (over current & earth fault) including fault level and phase along with date & time.

h. On-line display of current.

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i. Communicable with open Protocol having RS-485 port.

j. The relay should contain four shots, three phase, programmable & auto reclose control feature.

The relay shall be numerical type mounted in flush pattern on the panel board. The relay should be rated for 110V AC as well as DC & 5 Amper CT secondary. The relay should conform to latest IEC specifications. The tenders shall furnish the detail in this regard along with the offer.

Relay TTB shall have trip bypass arrangement.

All the relays shall be provided with test blocks in panel so designed that the relays may be tested at site.The relays should have provision of testing either through test block or test plug easily accessible by injecting the voltage / current/frequency (as applicable) from external testing instruments /source without first disconnecting/ reenergizing the primary electrical circuit protected by the relays. Facilities for isolating the tripping circuit during such testing shall also be provided.


The testing facilities provided in the relays shall be specifically stated in the bid. Necessary test plug etc. as may be required for proper testing shall be included in the contractor’s scope of supply. One test plug with five panels or part thereof are to be supplied.

The technical suitability of relays/schemes may also be examined by Protection Wing of Discoms & acceptability will be judged appropriately.

The bidder must furnish type test reports as per relevant ISS/ IEC along with bid to suit

the environmental conditions of our State, in respect of the relay (of the type and

design offered) which should have been type tested in NABL accredited test laboratory

in respect of such tests for which the lab has been accredited (for Indian make Relays)/

CPRI/ Nationally accredited testing laboratory (for Foreign make Relays).These type test

reports should not be older than Five years from the date of opening of bid.

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The Following makes of Relays are acceptable:-

f. Areva. g. ABB. h. Easun Reyrolle i. C&S j. JVS k. SEL l. ASHIDA m. MEGAWIN n. STELMEC o. CGL

Any other equivalent make of relays shall also be acceptable subject to prior approval of S.E. (TW), JVVNL, Jaipur.

5.2.15 WIRING :

All wiring shall be of switch board type consisting of copper conductor of 2.5 sq.mm cross section insulated with polyvinyl chloride insulation suitable for 660V service and in accordance with relevant IS:732. Polyvinyl chloride used shall have excellent resistance against burning, moisture, oil and vermin and shall be finished with clear colour. Rubber insulated wiring shall not be acceptable. Tenderers shall furnish the details of method being adopted by them for joint/ connections.

All instruments and panel wiring shall be of heat resisting and self extinguishing type in compliance with British Standard Practice/IS. Plastic or porcelain cleats of the limited compression type shall be used for holding wiring runs. All wires shall be suitable for bending to meet the terminal studs at right angles. Metal cases of all apparatus mounted on kiosk shall be separately earthed by means of copper wire or strips. The following colour schemes of the wiring shall be used as per IS:375.

a) AC three phase circuits :

i) No.1 phase : Red

No.2 phase : Yellow No.3 phase : Blue

ii) Neutral conductor : Black

iii) Connection to earth : Green

5.2.16 TERMINAL BLOCKS :

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Terminal blocks shall be 650 V grade, box clamp type ELMEX 10 sq.mm or approved equal. Not more than two wires shall be connected to any terminal. Spare terminals equal in number to 20% of active terminals shall be furnished.

Terminal blocks shall be located to allow easy access. Wiring shall be so arranged that individual wires of an external cable can be connected to consecutive terminals.

5.2.17 TEST TERMINAL BLOCK :

Two Nos. test terminal blocks shall be provided one for testing of relays and other for testing meters. They shall be of switch board type back connected for front of panel mounting. The test blocks shall provide complete isolation of meters, instruments etc. and the arrangement shall be such that testing power could be connected at the test block from any external source or may be taken from the instrument transformers. Provision shall be made for short circuiting current transformers. Suitable sealing arrangement shall be provided in test terminal blocks.

5.2.18 INDICATING LAMPS :

Indicating lamps shall be provided on the control board to indicate the following:

i) Visual indication of ON and OFF position of each circuit breaker. ii) PT supply indication.

Each lamp body shall be of moulded insulation and shall be able to withstand a high voltage test of appropriate value. All lamps shall be suitable for 240 V AC supply and shall have low power consumption and shall provide a wide angle of illumination of sufficient intensity for comfortable viewing. A glass of appropriate colour shall be screwed into the front of lamp body. The design of indication lamp shall be such as to facilitate replacement of burnt lamps. An engraved label indicating the purpose of the lamp shall be provided with each lamp.

5.2.19 FERRULES :

Ferrules engraved/printed with the same numbers, of symbols as indicated in the connections and wiring diagram shall be provided on the terminal ends of all wires for identification of circuits for inspection and maintenance. Ferrules shall be of strong and flexible insulating material with glossy finish to prevent adhesion. They shall be engraved/ printed and clearly marked and shall not be effected by dampness. Ferrule numbering shall be in accordance with IS:375. The same ferrules number shall not be used on wires in different circuits on a panel.

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5.2.20 HT TVM:-

3 phase 4 wire A.C. Static H.T. Trivector meter of accuracy class 0.5S for measurement of energy as per latest specification of JVVNL, shall be provided on each Outdoor VCB Kiosks.

Following makes of HT TVMs are acceptable:

i) Secure ii) L&T iii) ABB/Elster iv) Schlumberger v) Genus Infra

Any other make being procured by Nigam shall also be acceptable.

5.2.21 All interiors and exteriors of switchgear enclosure, breaker mechanism etc shall be

finished and painted to produce a neat, fire resistant and durable surface which would prevent rusting and corrosion. Sheet metal component shall be pre-treated using 7 tank phosphating process consisting of de-greasing, acid pickling, de- rusting, phosphating and passivation including repeated rinsing in between. On completion of the passivation of the components, they shall be preheated and then epoxy powder coated or treated with one coat of primer & zinc chromate and finished with two coats of light gray enamel paint of shade 631 of IS 5 and stoved to achieve excellent anti-rusting and scratch resistance properties. The thickness of painting shall be around 60 microns.

5.3 SCHEDUOLE OF EQUIPMENTS, FITTING & ACCESSORIES :

12 KV 630 Amps Vacuum circuit breakers kiosks for out door installation : 5.3.1 1 No. - 12 KV 630 Amp. Vacuum Circuit Breaker horizontal fixed type with provision

of manual tripping by means of push button and emergency shunt tripping.

Electrically operated through 230 V AC. A lockable Local/ Remote switch shall be provided, apart from Trip-Neutral-Close (TNC switch) control switch to select local/ remote operation of the switchgear. The breaker control switch shall have Trip- Neutral-Close position spring return sequence locking mechanism. The breaker control switch and selector switch shall be mounted on the front side of cubicle and located at a convenient height for easy operation.

5.3.2 1 No. - AC Motor charged spring operated closing mechanism or magnetic actuator type closing mechanism.

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5.3.3 1 No. - Shunt tripping arrangement/ Coil for operation on over current (load) and earth fault by relays along with emergency shunt tripping from remote place in addition to local emergency tripping(Mech.) One additional shunt trip coil, fitted very near to the original coil (which will be unwired) is also required to be provided.

5.3.4 3 Nos. - Single phase 12 KV Current Transformer ratio 400-200-100/5-5A suitable

for metering and protection. The class of accuracy shall be 0.5 for metering and 5P15 for protection. Rated burden (output) shall be 15 VA for each secondary winding and it should not be less than suitable for tripping arrangement provided. Instrument security factor for metering core shall not be exceed 5.

5.3.5 6 Nos. - Rigid type bimetallic/ aluminium alloy terminal connector suitable for ACSR

(10% Panther and 90% Dog Conductor) for both horizontal/ vertical take-off. 5.3.6 1 No. - Mechanical ON/OFF indicator.

5.3.7 1 No. - Operating handle for independent manual closing mechanism. 5.3.8 1 No. - Red indicating lamp for ON indication. 5.3.9 1 No. - Green indicating lamp for OFF indication. 5.3.10 Spare auxilliary contacts/switch having minimum 4 NO + 4 NC 5.3.11 1 No. - Flush mounting pattern 96x96 sq.mm Moving Iron ammeter of class 1.5

accuracy suitable scaled for 5 Amps. CT secondary. 5.3.12 1 No. - Ammeter selector switch to indicate phase current in all three phases and

with OFF position. 5.3.13 1 No. – Numerical 3 O/C + E/F relay. 5.3.14 1 No. HT TVM of accuracy class 0.5S as per latest specification of JVVNL. 5.3.15 2 Nos. - 240 V AC single phase 80 or 100 watt anti condensation heaters with

thermostat and switch. 5.3.16 1 No. - Automatic door illumination lamp with switch. 5.3.17 3 Nos. - 11000/110 V single phase voltage transformers each having 100 VA/phase

burden & class of accuracy 0.5 suitably connected to meters and indicating instruments etc.

5.3.18 1 No. - Flush pattern switch board mounting pattern 96x96 sq. mm moving iron

AC voltmeter of class 1.5 accuracy suitable for 110 V phase to phase secondary suitably scaled.

5.3.19 1 No. - Voltmeter selector switch to indicate phase to phase & phase to neutral

voltage of all the three phases. 5.3.20 3 Nos. - Indicating lamps coloured Red,Amber Blue for PT supply.

5.3.21 2 Nos. - Test terminal blocks to test meters and relays with sealing arrangement.

5.3.22 1 No. - Blank lable on the front of kiosks at the top.

5.3.23 Door locks with keys for all doors.

5.3.24 Pair of base channel for grouting in floor.

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5.3.25 Arrangement to check healthy trip circuit in all three phases (separate lamps for R phase, Y phase and B phase) be provided.

5.3.26 1 set - Self auxiliary plug and socket.

5.3.27 1 No. - ground bus system, size 50x6mm copper may be provided and the earthing

stud shall be capable of withstanding rated short circuit current and stud design shall be as per IS-133427 or IEC -200.

5.3.28 1 No. - Audio-Visual Annunciations.

5.3.29 1 No. - Operation counter. 5.3.30 1 No. - Name plate at front and back of each kiosk. 5.3.31 1 set - 3 phase air insulated main copper bus bar of 630 amp. continuous current

rating having maximum current density 1.5 Amp./ MM2 with minimum cross sectional area 600 MM2 with PVC insulation or sleeves, STC rating 16 KA for 3 sec.

5.3.32 Set -Power Pack arrangement system as specified in cl. No. 5.2.14. 5.3.33 1 No. -Spring Charge Indication Lamp.



5.4 MAKE AND TYPE OF BOUGHT OUT ITEMS :

Make / type of each relay, indicating instruments, integrating instruments, control switch for Circuit Breaker/Trip Transfer, selector switch for Voltmeter/Ammeter, Semaphore Indicator, indicating lamps, annunciator,

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Push Button, A.C. Hooter/Bell, D.C. Hooter, Heater, Link Type Test Terminal Block for testing of TVM, CFL Tube, 2/3 Pin Socket with Switch etc. shall be clearly and invariably indicated in the GTP (Guaranteed Technical Particulars), bill of material and unit price list. Only specific make accessories shall be indicated. The word "EQUIVALENT/REPUTED MAKE" will not be given for consideration.

The other makes of all bought out items shall be acceptable if it is of "ISI Marked" or type tested for which bidder shall furnish attested Photostat copies of ISI Certificate/type test reports not older than Five years for the respective make offered, subject to prior approval of SE(TW), JVVNL, Jaipur.

Other standard accessories which are not specifically mentioned but are required to be supplied with circuit breaker kiosk of similar type and rating for efficient and trouble-free operation.

5.5 TEMPERATURE RISE :

The max. temperature rise of various parts of the circuit breakers when tested under rated condition shall not exceed the specified values at a peak ambient temperature of 50 deg.C . The breaker may be provided with silver plated contacts if necessary to meet the requirement of IS:13118/IEC:56 where higher temperature rise is permitted with silver plated contacts. The quantity of silver facing shall be such that after carrying out one tenth of the total number of operations specified for mech. Endurance test, there is a still continuous layer of silver on the contacts. The temperature rise of CTs and PTs shall also not exceed the permissible values as per relevant Indian standards when corrected for max. ambient temperature at site.

6.0 TESTS :

6.1 TEST BEFORE DESPATCH : The 12 KV vacuum circuit breakers and accessories

shall be subjected at maker's works before dispatch, to the following tests as per relevant IS/IEC.

A) ROUTINE TESTS ON EACH UNIT AS PER RELEVANT STANDARDS :

(i) One minute power frequency voltage withstand dry

test on main circuit. (ii) Voltage withstand test on control & auxiliary

circuits. (iii) Measurement of the resistance of main circuit. (iv) Mechanical operating test. (v) Design and visual checks.

B) The following type tests shall be conducted on the material as per

relevant standards:

(i) Dielectric tests. a) Lightning Impulse Voltage Test.

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b) One Minute Power Frequency Test (Wet & Dry). (ii) Short time withstand current and peak withstand current test. (iii) Basic short circuit duties test. (iv) Single phase short circuit test. (v) Mechanical Operation test as per M-2 class. (vi) Out of phase making & breaking test. (vii) Capacitive Current Switching Test.

a) Cable Charging Test. b) Single Capacitor Bank Current Switching Test.

(viii) Measurement of resistance of main circuit. (ix) Temp. rise test. (x) IP-55 Test (For cubicle/control cabinet). (xi) Any other type tests not specified above but

covered as per amendment/latest edition of relevant IS/IEC.

C) The type test reports of Circuit Breakers, Current Transformers, Potential Transformers, Relays, Meters etc. shall be complete in all respect as per relevant IEC/ISS.

6.2 TYPE TESTS :

The 12 KV vacuum circuit breaker kiosk offered shall be fully type tested as per relevant standards.

The bidder must furnish type test reports along with bid as per the qualification requirement of the Tender Specification.

Where permitted in the relevant standard, a test specimen for type test may be a representative sub-assembly/ a representative functional unit. An individual type test is acceptable for a change of constructional detail, for any change in the design/type of type test report and the design/type of offered against this specification, if the manufacturer can demonstrate and purchaser is satisfied that this change does not influence the result of the individual type test. The bidder may bring out in their offer all such changes made in components, materials, design etc. as the case may be. The purchaser will interpret the meanings of drawings and specifications and shall have the power to accept/reject any type test report which in his judgment is/is not in a manner acceptable to him. The decision of Purchase Committee in this matter shall be final and binding to all.

However, the purchaser reserves the right to demand repetition of some or all the type tests in presence of purchaser's representative. For this purpose, the bidder should indicate unit rates for carrying out such type tests. These test charges shall not be taken into consideration for bid evaluation.


Tests are not required to be performed on bought out equipments/items like motor, terminal connector, etc. at the works of manufacturer. Furnishing Test Certificate of

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these items from the original equipment manufacturers shall be deemed to be satisfactory evidence. Inspection of the tests at Sub-contractors works will be arranged by the supplier whenever required.

6.4 ROUTINE/ACCEPTANCE TESTS :

(i) The following acceptance and routine tests shall be got conducted in presence of purchaser's representative as per stipulation of the relevant standards, on each unit. a) One minute power frequency voltage withstand dry test on main circuit. b) Voltage withstand test on control & auxiliary circuits. c) Measurement of the resistance of main circuit. d) Mechanical operating test. e) Design and visual checks

(ii) Inspection & tests on control gear.

In addition to the above tests at 6.4 (i) above specified by IEC, the following shall also be performed at manufacturer's works in presence of purchaser's representative after completely assembling the kiosk.

a) Checking wiring of circuits and their contacts. b) Insulation resistance of complete wiring, circuit by circuit with all equipment

mounted on the panels. c) Checking of operational protective schedule , instruments and meters. d) Checking of phase faults between R&Y, Y&B and B&R phases. Kiosk should

trip under all three conditions. (iii) Temp. rise test on one No. Kiosk in the first offered lot shall also

be done in the presence of the purchaser's representative. (iv) Any other tests not specified above but covered as per amendment/latest

edition of relevant IS/IEC. 6.5 TOLERANCE ON TEST RESULTS :

As per relevant standards/specification.

6.6 TEST AT SITE :

The purchaser reserves the right to conduct all tests on 12 KV circuit breakers after arrival at site and the contractor shall guarantee test certificate figures under actual service conditions.

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7.0 DOCUMENTATION

7.1 All drawings shall conform to International Standards Organization (ISO) À', series of drawing sheet/Indian Standards specification IS:13118/IEC-56. All drawings shall be in ink and suitable for micro filming. All dimensions and data shall be in S. I Units.

7.2 List of drawings and documents

The bidder shall furnish four sets of following drawings along with his offer.

a) General outline and assembly drawings of the equipment i.e. breaker,

CTs,PTs etc.

b) Graphs showing the performance of equipments in regard to magnetization characteristics.

c) Sectional views showing -

i) General Constructional features. ii) the materials/ gaskets /sealings used. iii) the insulation, the winding arrangements, method of connection of the

primary/secondary winding to the primary /secondary terminals etc. iv) porcelain used and its dimensions along with the mechanical and

electrical characteristics.

d) arrangement of terminal's and details of connection studs provided.

e) Name Plate

f) Schematic drawing

g) Type test reports in case the equipment has already been type tested.

h) Test reports, literature, pamphlets of the bought out items, and raw material. 7.3 The manufacturing of the equipments shall be strictly in accordance with the


7.4 Approval of drawings/work by purchaser shall not relieve the supplier of his

responsibility and liability for ensuring correctness and correct interpretation of the drawings for meeting the requirement of the latest revision of applicable standards, rules and codes of practices. The equipment shall conform in all respects to high standards of engineering, design, workmanship and latest revisions of relevant standards at the time of ordering and purchaser shall have the power to reject any work or materials which, in his judgement is not in full accordance therewith.

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8.0 PERFORMANCE WARRANTY PERIOD :

The performance warranty period shall be 5 (Five) years from the date of receipt of equipment along with its all accessories.

The supplier will be required to furnish a Performance Bank Guarantee @ 10% (for new suppliers)/ @ 5% (for old & established suppliers) amount of the total ordered value, which is required to be valid for 5 years.

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TECHNICAL SPECIFICATION OF BATTERY CHARGERS SUITABLE FOR 110V-120 AH CAPACITY BATTERY SETS

1.0 SCOPE :

The specification covers design, manufacture/ fabrication, shop test and offer for

inspection, testing and checking before delivery of battery chargers duly packed suitable for indoor installation at various Grid sub stations in Jaipur Discom. These equipments are to be completed in very respect/details to the functions designated and to the entire satisfaction of the purchaser. It is required that the supplier in accepting the contract agrees to furnish all apparatus, appliances and material whether specifically mentioned or not, but which may be found necessary to complete to perform & testing any of the herein specified equipment, for compliance with the requirements implied without extra charges.

Consideration may be given by the purchaser to alternatives which the supplier

considers advisable by reason of his own manufacturing requirements and experience, provided descriptive matter is submitted pointing out the recommended device or arrangements equal to or superior to that required by the accompanying specification with full justification.


i) Peak ambient temperature 50 Degree C in shade.

ii) Maximum average ambient 40 Degree C

temperature in a 24 hours period in shade.

iia) Maximum yearly weighted average

ambient temperature 35 Degree C

iii) Maximum temperature attainable 60 degree C by an object exposed to sun.

iv) Maximum relative humidity. 100%

v) Average number of thunder 40 storm days per annum.

vi) Average number of rainy days 100 per annum.

vii) Average annual rainfall 10-100 cm

viii) Number of months of tropical 4 months monsoon conditions.

ix) Maximum wind pressure. 100 Kg/Sq.m

x) Altitudes Not exceeding 1000 mtrs.

3.0 STANDARD :

The Battery Chargers shall conform to the latest edition of IS:3136/1965 &

IS:4540/1968.Alternatively all materials and components shall be designed and manufactured in accordance with the standards of the International Electro-technical Commission (IEC) or the American Standards specification or the appropriate German or Swiss Standards. Where a

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certain equipment is stated not to comply with the Indian Standard or in the absence of requisite Indian Standards to the relevant International Standards the salient points of difference, merits and demerits between standards adopted and the Indian Standards or the British Standards shall be clearly brought out in the bid making at the same time, due correction for operation under the climatic conditions specified herein. A set of standards adopted translated in English, if it is in a language other than English, shall also be enclosed with the tender, to enable due comparison, where ever a standard is specifically mentioned in these specifications. it is understood that the corresponding standards or standard from amongst the sources mentioned above shall also apply.

Equipment meeting the requirements of any other authoritative standards which

ensures a quality equal to or better than that as per the standards mentioned above, shall also be acceptable. Where the equipment conforms to any other standards, salient points of difference between the standards adopted and the specified standards shall be clearly brought out in the tender.

4.0 PRINCIPAL PARAMETERS:

The battery chargers to be supplied by the supplier shall meet the requirements of

relevant ISS if comes later on for battery chargers at the time of supply or any other international standards and shall be suitable for continuous operation for the climatic conditions specified in the specification. Battery chargers shall be of sufficient capacity to suit battery sets of 110V, 120 AH Capacity. The battery chargers suitable for 110V-120AH battery sets shall be operative from single phase, 50 Hz, 230 Volts AC supply. The battery charger shall be operative on Thyristor based Silicon Controlled Rectifier (SCR) both for float & boost section.

5.0 TECHNICAL DESCRIPTION OF CHARGER :

The equipment shall be suitable for float charging , as well as quick charging of associated battery sets of 110 V 120 AH ratings. The bus bar voltage shall be maintained at all times even during quick charging.

Suitably constant potential controller shall be provided for maintaining constant

voltage across float charger. The Battery Charger should be of automatic float/ boost type and should have constant voltage and constant current characteristics.

During normal working conditions, the float charger shall supply the load current and

also keep the batteries on `Float'. The boost charger will remain off under these conditions. During failure of mains supply, the load be automatically fed by the batteries (time delay not permitted).

On resumption of supply, the batteries may need to be boost charged. Since the voltage

across the cells may fall upto 1.8 Volts/Cell after discharge, therefore, the boost charger should be capable of charging these cells from 1.8 Volts/Cell to 2.35 Volts/Cell. Under such conditions, voltage across the load should not increase the rated value and only part of the battery should be connected across the load. Even during boost charging normal load will be supplied by float charger.

The float and boost charger should also have provision for change over to the manual

mode, in case the electronic circuit stablising the DC output fails. For this purpose, suitable arrangement should be made. Also Facility should be provided to prevent the excessive in-rush current into the battery, when the discharged battery suddenly comes across the float charger after an emergency period. The ripple content of the out put across load (in float section) shall be less than 1% in case of battery chargers suitable for 110V-120AH batteries.

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The rectifier used in the battery charger shall be of robust construction and shall be of silicon type. The tenderers shall supply the characteristics of the rectifier used in the construction of the charger indicating the capacity of the rectifier to suit the temperature conditions.

The float section of the charger suitable for 120 AH batteries shall be capable of

delivering a continuous load of 12 Amps. Also the boost section of charger suitable for 120 AH batteries shall be capable of delivering a continuous load of 18 Amps.

5.1 Battery charging equipment causing unbalance in charging current of various cells of the

battery shall not be acceptable. All cells will receive adequate and permissible value of charging current. There should not be any discontinuity of DC supply to the bus bar during any transition period and battery power should be available for tripping circuit , if necessary, even during quick charging.

5.2 The float as well as boost section of the battery charger should be able to stabilise the

DC output voltage within plus/ minus 1% and with the variation of plus minus 10% in the AC supply with simultaneous load variation from 0 to 100% of rated current.

5.3 The DC voltmeter and ammeters will be provided with class of accuracy 1.5 to indicate

voltage and the rate of charge/discharge current. The charger shall be completed with the necessary transformer, chokes, capacitors, input output switches etc. An A.C. voltmeter of class of accuracy 1.5 with selector switch should also be provided at AC incomming supply. An ammeter of class of accuracy 1.5 is also to be provided in boost charger. Weak links such as fuses, relays etc. shall not be provided between the chargers, batteries and load to ensure continuity of DC supply. However suitable AC/DC switches/contactors of appropriate rating shall be provided to cut off AC/DC supply for repair and maintenance if considered so necessary. In that case the battery would directly feed the load.

5.4 All the electronic components shall be of high MTBF or heavy duty type and liberally rated.

These shall be housed in a well ventilated sheet steel cubicle complete with input and output terminals. The charger shall be assembled in a sheet steel cubicle with suitable angle iron structure Louvres will be provided for ventilation backed up by fine wire mesh. Thickness of the sheet steel used for cubicle shall be as follows:

------------------------------------------------------------ S.No. Battery charger Thickness of the sheet steel for

suitable for. --------------------------------- Front/Top/ Bottom Sides Rear

------------------------------------------------------------ 1. 110V-120AH BATTERIES 2mm 1.6 mm -------------------------------------------------------------

5.5 The unit shall be provided with audio and visual alarm for the following faults :

a) Input supply fuse failure float. b) Input supply fuse failure boost. c) Float charger rectifier fuse fail. d) Boost charger rectifier fuse fail. e) AC mains failure. f) Condenser fuse failure in float and boost.

The audio alarm shall ring under all fault conditions.

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5.6 Soft start feature/ automatic run down circuit shall be provided so that at the incidence of power failure, the DC output voltage of the float and boost chargers reach the minimum position automatically and, therefore, when the power is resumed the voltage reaches a normal floating level from the minimum voltage slowly, by which the excessive in rush current into the discharged battery is minimised.

5.7 Current limiting circuit shall be provided to protect the float charger as well as boost charger

also.

5.8 Keyed push button arrangement shall be provided by which the boost charger can be used as a float charger, whenever the float charger is down due to any defect or failure.

5.1 FITTING & ACCESSORIES :

All cabling and wiring shall be neatly secured in position and adequately supported.

All cable and wires carrying A.C. main supply shall be kept separate from other cables. The colour scheme for the cabling and wiring shall be as per IS. All wiring shall be neatly laid down well.

The following colour scheme of the wiring shall be used :

(I) AC Single Phase Circuit :

a) Phase (L) - Red

(II) Neutral Conductor. - Black

(III) Connection to earth. - Green

(IV) D.C. Circuits. - Grey

5.1 SWITCH BOARD LIGHTING :

The switch board interior shall be illuminated by incondescent lamps connected to a 230V single phase AC supply. The illumination of interior shall be free from hand shadows and shall be planned to avoid any strain or fatigue to the wire man, who may be called upon to do work.

5.2 PAINTING :

All CRCA sheet steel work shall be phosphated in accordance with IS:6005 code

practice for phosphating iron and steel. Rust and scale shall be removed by picking with dilute acid followed by washing with running water rinsing with slightly alkaline hot water and drying. The phosphate coating shall be sealed with application of two coats of ready mixed stored type zinc chromate primer. The first coat may be "Flash Dried" while second coat shall be stored. After application of primer two coats of finishing synthetic enamel paint shall be applied. Generally the exterior colour of paint shall be as per shade No. 631 of IS:5 and the interior colour of paint shall be white.

5.3 NAME PLATE

The battery chargers shall be provided with non-corrosive legible name plate indelibly

marked with the following information:

1. Jaipur Vidyut Vitran Nigam Ltd. 2. TN/IPDS 3. Manufacturer's name or trade mark & identification no.

of charger being supplied.

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4. Rating of charger (Float & Boost) 5. Input & Output Voltage. 6. Year of manufacture.

6.0 TESTS :

6.1 Type tests:

The following tests shall constitute the type tests as per IS: 3136-1965 and IS:4540-1968

(latest amended):

a) DC voltage current test. b) Automatic voltage regulator operation. c) Efficiency test. d) Ripple Voltage test. e) High Voltage test. f) Temperature rise test.

6.2 ROUTINE/ ACCEPTANCE TESTS:-

The following tests shall be carried out :

a) DC voltage current characteristics. b) High voltage test at 2 kV for one minute. c) Inspection. d) Auxiliary devices. e) Alternating Current easurement. f) No load test. g) Load test. h) Insulation resistance test. i) General performance test at various loads. j) Dimensional checking and sheet steel thickness measurements. k) Checks on annunciation circuits.

Efficiency test & temperature rise test shall also be carried out on one unit in the

presence of purchaser's representative.

6.3 TYPE TEST CERTIFICATES TO BE FURNISHED WITH BID :

The equipment offered, shall be fully type tested as per the relevant standard. The bidder must furnish type test certificate in respect of type tests as indicated at clause No. 6.1 above for the type and design offered with the bid.

All these above type tests must have not been conducted earlier than five years from the

date of opening of bid. The bids received without these type test certificates will be treated as non-responsive.

The tenderers will also submit following for Battery Chargers with their tenders without

which the offers shall be rejected and treated as non-responsive.

i) Circuit diagram of battery charger. ii) Dimensional drawing of battery charger. iii) List of components with ratings, makes and rates.

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The purchaser reserves the right to demand repetition of some or all the type tests in presence of purchaser's representative.

6.4 SAMPLING PLAN:

The samples, for routine inspection, testing and checking shall be selected by our

inspecting officer at random from the offered lot as under: ------------------------------------------------ Size of Lot No. of Samples ------------------------------------------------ 1 to 10 6 Nos. from 11 to 20 6+30% qty.exceeding 10 Nos. from 21 to 40 9+25% qty.exceeding 20 Nos. from 41 to 80 14+30% qty.exceeding 40 Nos. from 80 & above 26+10% qty.exceeding 80 Nos. ------------------------------------------------

6.5 TEST AT SITE :

The purchaser reserves the right to conduct all the test on the Battery charger after

arrival at site and the contractor shall guarantee test certificate figures under actual service conditions.

7.0 INSPECTION

All the tests and Inspection shall be made at the place of manufacturer unless otherwise especially agreed upon by the bidder and purchase at the time of purchase. The bidder shall afford the inspection officer(s) representing the purchaser all reasonable facilities without charges, to satisfy him that the material is being furnished in accordance with this specification. The purchaser has the right to have the tests carried out at his own cost by an independent agency whenever there is a dispute regarding the quality of supply.

The Inspection may be carried out by the purchaser at any stage of manufacture/ before dispatch as per relavant standard.

Inspection and acceptance of any material under the specification by the purchaser,

shall not relieve the bidder of his obligation of furnishing material in accordance with the specification and shall not prevent subsequent rejection if the material is found to be defective. The Bidder shall keep the purchaser informed in advance, about manufacturing programme so that arrangements can be made for inspection.

The purchaser reserves the right to insist for witnessing the acceptance/ routine

testings of the bought out items. 8. QUALITY ASSURANCE PLAN :

8.1. The tenderer shall invariably furnish following information alongwith his offer,

failing which his offer shall be liable for rejection. Information shall be separately given for individual type of equipment offered. (i) Statement giving list of important raw materials names of sub-suppliers for the

raw materials, list of standards according to which the raw materials are tested. List of tests normally carried out on raw materials in presence of tenderer's representative, copies of test certificates.

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(ii) Information and copies of test certificates as in (i) above in respect of bought out accessories.

(iii) List of manufacturing facilities available.

(iv) Level of automation achieved and list of areas where manual processing exists.

(v) List of areas in manufacturing process, where stage inspections are normally

carried out for quality control and details of such tests and inspections. (vi) ial features provided in the equipment to make it maintenance free.

(vii) List of testing equipment available with the tenderer for final testing of equipment

spefified and test plant limitation. If any, vis-a-vis the type, special acceptance and routine tests specified in the relevant standards. These limitations shall be very clearly brought out in schedule of deviations from specified test requirements.

8.2 The successful tenderer shall within 30 days of placement of order, submit

following information to the purchasers.

(i) List of raw material as well as bought out accessories and the names of sub suppliers selected from those furnished alongith offer.

(ii) Type test certificates of the raw material and bought out accessories.

(iii) Quality Assurance Plan (QAP) with hold points for purchaser's inspection. The

quality assurance plan and purchaser's hold points shall be discussed between the purchaser and supplier, before the QAP is finalised.

8.3 The successful tenderer shall submit the routine test certificates of bought out

accessories and central excise passes for raw material at the time of routine testing of the fully assembled equipment.

9. DOCUMENTATION:

The bidder shall submit the detailed drawings indicating the dimensions for

battery charger. The successful tenderer shall within 2 weeks of placement of order submit three sets of final version of all the drawings for purchaser's approval. The purchaser shall communicate his comments/ approval on the drawings to the supplier within four weeks. The supplier shall if necessary modify the drawings and resubmit the three copies of modified drawings for purchaser's approval within two weeks from the date of purchaser's comments.

The manufacturing of equipments shall be strictly in accordance with the

approved drawings and no deviation shall be permitted without the written approval of purchaser.

The approval of drawing by purchaser shall not relieve the supplier of his

responsibility and liability for ensuring correctness and correct interpretation of the drawings for meeting the requirements of the latest revision of applicable standards, rules

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and code of practices. The equipment shall confirm in all respect to high standards of engineering, design, workmanship and latest revisions of relevant standards at the time of ordering and purchaser shall have the power to reject any work of materials which in his judgment is not in full accordance therewith.

10. PACKING & FORWARDING 10.1 The equipment shall be packed in creates suitable for vertical/horizontal transport

as the case may be, and suitable to withstand handling during transport and outdoor storage during transit. The supplier shall be responsible for any damage to the equipment during transit due to improper and inadequate packing. The easily damageable material shall be carefully packed and marked with the appropriate caution symbol Wherever necessary proper arrangement for lifting, such as lifting hooks etc. shall be provided. Any material found short inside the packing cases shall be supplied by the supplier without any extra cost.

10.2 Each consignment shall be accompanied by a detailed packing list containing the

following information:

a) Name of the consignment

b) Details of consignment

c) Destination

d) Total weight of consignment

e) Signs showing upper/lower side of the crate.

f) Handling and unpacking instructions.

g) Bill of material indicating contents of each package.

10.3 The supplier shall ensure that the packing list and bill of material are approved by the purchaser before dispatch.

11.0 GUARANTEE PERIOD OF BATTERY CHARGERS :

The guarantee period of each Battery Charger along with all accessories shall

be for the period of 5 years from the date of receipt of equipment along with all

accessories.

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12. MAKES OF BROUGHT OUT ITEMS:-

Makes of following items are only acceptable to Nigam:-

S.No. Item Make

1 Blocking Diodes RIR/HIRECT/ NSL/ USHA

2. Thyristors RIR/HIRECT/ NSL/ USHA

3. HRC Fuses As per IS/IEC

4. Filter Capacitors ALCON/ SARDA/ RESCON

5. AC Contactor TC/ SCHNEIDER/ L&T/ GE/ BCH/ HUNDAI

6. DC Ammeter AE/MECO/ RISHLINE/ IMP

7. DC Voltmeter AE/MECO/ RISHLINE/ IMP

8. AC Ammeter AE/MECO/ RISHLINE/ IMP

9. AC Voltmeter AE/MECO/ RISHLINE/ IMP

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TECHNICAL SPECIFICATION FOR SUPPLY OF HOT DIP GALVANISED STEEL STAY WIRE 7/8 SWG

1. SCOPE

This specification covers, manufacture, design, inspection ,testing before dispatch of hot dip heavily galvanized stranded steel stay wire(7/8 SWG) , complete in all respect as per GTP/ISS

Hot dip galvanized steel stay wire of 550-900 N/mm

Quality confirming to IS-2141/2000 in all respect Including chemical composition (Heavily coated Hard quality) of dia 7/4 mm(7/8 SWG)


XXI. Peak ambient temperature 50 Degree C

XXII. Maximum average ambient temperature 40 Degree C

XXIII. Maximum temperature attainable 60 Degree C

XXIV. Maximum relative humidity 100 %

XXV. Minimum relative humidity 50 %

XXVI. Average number of thunder storm days per annum 40

XXVII. Average number of rainy days per annum 100 XXVIII. Average annual rainfall 10-100 cm

XXIX. Maximum wind pressure 100 Kg/sq.m

XXX. Altitudes not exceeding 1000 mtrs

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3. STANDARDS

The finished material shall comply in all respect with the requirement of the latest edition of the relevant ISS as mentioned below:-

(i) The hot dip galvanized stranded steel stay wire (heavily coated) shall comply with the ISS:2141/2000, 4826/1979 and 6594/1977 with latest amendments thereof, if any in all respects, except herein otherwise stated, corresponding to grade-4 550- 900 N/mm sq. minimum tensile strength quality. The galvanization coating of galvanized steel wire and technical supply conditions shall conform to IS:4826/1979 and IS:6594/1977 or latest amendment thereof if any.

(ii) Goods meeting other authoritative standards which ensure an equal or higher quality than the standards mentioned above will also be accepted.

The galvanized stranded steel stay wire shall be capable of withstanding the normal handling necessary for transportation and erection.

4. WORKMANSHIP: The wire shall be manufactured from steel made by any suitable process(es) as mentioned in IS:2141/2000 & 7887/1975 and shall not contain sulphur and phosphorus exceeding 0.060 percent each.

Each coil shall be warranted to contain the joints only as permitted under relevant IS:2141/2000.

The galvanized stranded steel stay wire shall be well and clearly drawn to the dimension specified. The wire shall be free from scale, irregularities, imperfections, flaws splits and other defects and shall be uniformly galvanized having smooth and even zinc coating. The requirement for chemical composition of the wires shall conform to the value as specified in IS/7887/1975 and IS:280/1978.

5. ISI CERTIFICATION The supplier must hold the licence of ISI mark.

6. QUALITY ASSURANCE PLAN

The supplier shall invariably furnish the following information alongwith his offer, failing which his offer shall be liable for rejection.

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a) Statement giving list of important raw materials, names of sub-suppliers for the raw materials, list of standards according to which the raw materials are tested, list of tests normally carried out on raw materials in the presence of supplier’s representative and copies of test certificate.

b) Information and copies of test certificates as in (i) above in respect of bought out material.

c) List of manufacturing facilities available. d) Level of automation achieved and list of areas where manual processing exists. e) List of areas in manufacturing process, where stage inspections are normally carried out

for quality control and details of such test and inspection. f) List of testing equipments available with the supplier for final testing of G.S. stay wire

and test plant limitation if any vis-à-vis the type, special acceptance and routine tests specified in the relevant standards. These limitations shall be very clearly brought out in schedule of deviation from specified test requirements.

7. INSPECTION, TESTING & CHECKING BEFORE DISPATCH:

All the tests and inspection shall be carried out at the works of manufacturer unless otherwise specifically agreed upon by the bidder and purchaser at the time of purchase. The bidder shall provide all reasonable facilities to the inspecting officer(s) without charges.

The inspection may be carried out by the purchaser at any stage of manufacture/before dispatch as per relevant standard. The purchaser has the right to have the tests carried out at his own cost by an independent agency whenever there is a dispute regarding the quality of supply.

Inspection and acceptance of any material under the specification by the purchaser, shall not relieve the bidder from his obligation of furnishing material in accordance with the specification and shall not prevent subsequent rejection if the material is found to be defective. The bidder shall keep the purchaser informed in advance, about manufacturing program so that arrangements can be made for inspection.

(A) TEST BEFORE DISPATCH: The stay wire shall be subject to the following tests as per ISS at manufacturer’s works before dispatch,.

ROUTINE/ACCEPTANCE TEST:- The following tests on selected samples as per relevant standard shall be got conducted in presence of purchaser’s representative.

(i) Tensile and Elongation test (ii) Adhesion and wrap test (iii) Zinc uniformity and coating test (iv) Chemical analysis test (v) Dimension and weighment checkup of sample coils. (vi) Lay ratio

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(B) SAMPLING PLAN: As per the provisions of IS:2141/2000.

(C) TOLERANCE ON TEST RESULTS

vii) Weight of the coil – 40-60 Kg per coil. viii) Dia of wire ±2.5% of wire dia with a minimum of 0.025 mm ix) Lay length -12 to 18 times strand dia x) Tensile and elongation test –As prescribed in IS:2141/2000. xi) Zinc uniformity and coating test – As per IS:4826 xii) Chemical composition test IS:7887

8. MARKING


9. PACKING AND FORWARDING: he galvanized steel stay wire shall be supplied in coils. Each coil of GSS wire shall have single continuous length and shall be suitably bound and fastened compactly and shall weigh 40 kgs to 60 kgs. The coils will be suitably protected by wrapping round by hession cloth/polythene cover to avoid damage in transit and corrosion. Each coil shall be marked as mentioned above.

10. TYPE TEST / CHECKING OF MATERIAL AT STORES

The material received in the stores shall be subject to test checking at CTL of Nigam before final acceptance of the material. The procedure for the CTL test shall be as under :

SAMPLING

One sample out of each lot/sub-lot of 400 Nos coils or part thereof from each inspected lot received in stores shall be selected subject to maximum 7 samples for test checking of material and shall be got tested at the CTL of JVVNL. The sample selection shall be done in the presence of supplier or his authorized representative for which advance notice shall be given to the supplier.

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TESTS AT CTL

The following tests shall be carried out on the selected samples of G.S.Stay wire as per relevant standards:-




11. CRITERIA FOR ACCEPTANCE OF ABOVE TEST

The inspected material should be strictly in accordance to the relevant ISS / GTP of the specification, however, the material shall be accepted on the basis of test results found/observed during test at CTL as mentioned below.

(a) For uniformity of galvanization test.

(i) The sample shall be first tested for (n-1) number of dips where n is specified No. of dips of one minute in the contract. If the sample does not pass the uniformity of galvanization test for (n-1) dips, the material shall be rejected and the relevant lot/sub-lot to which the sample pertains shall have to be replaced by the supplier free of cost.

(ii) If the material has passed the uniformity of galvanization test for (n-1) dips then it shall be tested for last one dip of one minutes to complete the test for ‘n’ dips. If the sample does not pass the uniformity of Galvanisation Test with ‘n’ then material pertaining to relevant lot/sub-lot shall be accepted with a deduction @ 5% of cost of material

(iii) If the sample(s) have passed the Test with number of dips as specified in the

contract (n) , then material pertaining to relevant lot/sub-lot shall be accepted.

b) Tensile test:-

If the material fails in tensile test the same shall stands rejected.

c) Dimensional check If the material fails in dimensional check the same shall stands rejected.

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TECHNICAL SPECIFICATION FOR OUTDOOR TYPE 33 KV CTs 1.1 SCOPE:

This specification covers the design, manufacture, assembly testing at

manufacturer's works before dispatch, supply and delivery of Single Phase 50 Hz oil immersed, self cooled, hermetically sealed, outdoor type 33 KV Current Transformers for installation at various Grid Sub-stations of Jaipur Discom. Consideration may be given to alternatives which the suppliers consider advisable by reason of his own manufacturing requirements & experience provided descriptive matter/ tests certificates are submitted pointing out the recommended device or arrangement equal to or superior to that required by this specification and if the purchaser is convinced of the quality and/or superiority of the equipment. These equipment shall be suitable for installation in system with neutral effectively grounded.

1.2 STANDARDS:

The design, manufacture & testing of various equipments, covered by this

specification shall comply with the latest issue of following and other applicable standards except the value wherever specified shall be considered relevant:-

IS:2705 Specification for Current Transformers IS:2099 Specification for Bushing IS:5621 Specification for hollow porcelain bushing. IS:5561 Specification for electric power connectors. IS:335 Specification for new insulating oil. IS:4201 Application guide for Current Transformer. IEC:60044-1 & 2 Instrument Transformers

Equipments conforming to other International and IEC Standards which ensure equal or higher quality than the standard(s) mentioned above would also be acceptable. In case the tenderer wishes to offer equipment conforming to other standard, they shall furnish English translation of the relevant standards


The climatic conditions under which the equipment will be required to operate satisfactorily are as under:-

i) The equipment offered by you shall conform in all respects to the relevant

Indian standards specifications except where stated otherwise in the order. Special care shall be taken in the design & manufacture of equipment to take into account the tropical conditions such as high temperature excessive humidity, dust & salt laden atmosphere at detailed below:-

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a) Maximum temperature of air in shade : 50 deg.C b) Minimum temperature of air in shade : (-) 5 deg.Cc) Maximum relative humidity : 95 %d) Minimum relative humidity : 10 %e) Height above mean sea level : upto 1000 meters f) Dust storms are likely to occur

the period from March to July

g) Average number of thunder storms : 40days/annum. h) Average number of tropical monsoon : 4 months conditions per annum.i) Average rain fall : 10-100 cms. depending upon area.

ii) TROPICAL TREATMENT:

All the equipment shall be suitably designed and treated for normal life and satisfactory operation under the hot and humidity Tropical Climatic Conditions specified under clause No. 3.03 above and shall be dust and vermin proof. All the parts and surface which are subject to corrosion shall be made of such material and shall be provided with such protective finish as would protect the equipment installed from any injurious effect of excessive humidity.

You shall supply all such minor accessories required for the completion of the supply which have either not been specifically mentioned in this specification or your tender offer.

1.3 TECHNICAL REQUIREMENTS FOR 33 KV CURRENT TRANSFORMERS:

i) The Current Transformers shall be of Single Phase oil immersed self cooled hermetically sealed & outdoor type suitable for the service conditions indicated complete in all respects conforming to latest issue of IS mentioned at clause 3.02 and modern practice of design & manufacture. The thickness of tank sheet shall be minimum of 3mm.

ii) The core shall be of high grade non-aging laminated silicon steel of low

hysteresis losses and high permeability to ensure accuracy at both normal & over current.

iii) The Current Transformers shall be hermetically sealed to eliminate breathing

and prevent air and moisture from entering the tank. The method adopted for hermetically sealing shall clearly be stated in detail in the offer. These shall be provided with prismatic oil level gauge and pressure reliving devices capable for releasing abnormal internal pressure where necessary. Arrangement for oil filling/ drain valve/ plug / hole shall be sealed to avoid leakage / pilferage of oil. The arrangement provided shall be indicated in the tender. For load shedding single phasing is adopted in the system. The offered CTs shall be suitable for working under such conditions.

iv) For 33 KV CTs only live tank type design shall be acceptable

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v) PRINCIPAL TECHNICAL PARTICULARS OF CURRENT TRANSFORMERS:-

S. No.

Description

Particulars

1. Type of CT/Installation Single Phase Live Tank oil filled hermetically sealed,

outdoor type.

2. Type of mounting Steel Structure

3 Nominal system voltage 33KV

4 Highestsystemvoltage

36KV

5 Rated Insulation level.

a. One minute dry power frequency withstand voltage.

70KV (rms)

b. 1.2/50 micro second Lightning Impulse voltage (KVP)

170 KV peak

6 One minute High voltage power frequency test on

a. Primary winding (test voltage) As per IS:2705/1992 (with latest amendment)

b. Secondary winging (test voltage) As per IS:2705/1992 (with latest amendment)

7 Frequency 50Hz.

8 Transformation ratio(s) (a) 400-200-100/5-5A (b) 240-120-60/5-5A

9. Method of earthing of system Effectively earthed

10. Rated continuous Thermal current(s) rating(s)

120% of rated primary current (s)

11. a) Rated short time thermal current. 25 KA (rms) for 1 Sec.

b) Rated dynamic current (kAP) 62.5

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12. Temperature rise for rated continuousthermal current over an ambient temp.of 50 Deg. C.

Within limits of IS:2705/1992 with latest

amendments.

13. Total creepage distance of porcelain housing (Min.)

900 mm

14. Max. Creepage factor for hollow porcelain insulator

4.0

15. Core utilization for CTs having ratio

(a) 400-200-100/5-5 Amp. (b) 240-120-60/5-5 Amp.

CORE-I CORE-II

Meteringm Back up protection

a. Rated burden VA 30 40

b. Class of accuracy 0.5S 5P

c. Max. instrument security factor 5 -

d. Accuracy limit factor (max.) - 15

vi) Necessary magnetization curve for the relevant core(s) shall be furnished.

vii) TEMPERATURE RISE FOR CURRENT TRANSFORMERS :

The limits of temperature rise of the windings, external surface of the core and other parts of the current transformers when carrying a primary current equal to the rated continuous thermal current at the rated frequency and with rated burden shall be governed by the provisions of latest issue of IS:2705 (Pt.I). The corresponding temperature rise for the terminal connectors shall not exceed at rated continuous thermal current of the CT beyond the limits prescribed in IS:5561/1970 or latest issue.

1.4 CORES AND WINDINGS FOR ALL CLASS CURRENT TRANSFORMERS

i) The current transformers core to be used for metering and instrumentation shall be of

the accuracy class as specified. The saturation factor, instrument security factor of this core shall be low enough so as not to cause any damage to measuring instruments in the event of maximum short circuit current. Mu-metal or equivalent material shall be used for this purpose. This factor shall not exceed to 5 on all transformation ratio.

ii) The current transformers cores to be used for protective relaying shall be of accuracy

specified. The cores shall be designed for a maximum accuracy limit factor of 15 or min. knee point voltage specified as the case may be. The magnetization curves for applicable core shall be furnished by the tenderer along with the tender failing which offer is likely to be ignored.

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iii) The rating of the secondary winding shall be as per Clause No. 3.04(v) of this specification. The secondary terminals shall be brought out in a weather proof compartment on one side of current transformer for easy access and shall be provided with short-circuiting arrangements. Required transformation ratio can be achieved in any manner but the current transformers will have to satisfy the requirement of rated VA burdens, class of accuracy, accuracy limit factor, instrument security factor and short time thermal rating etc. as specified in Clause 3.4 (v) at all transformation ratio.

The minimum knee point voltage and maximum secondary winding resistance shall correspond to the lowest ratio. In case tapings are provided on secondary side of current transformers to get the designed transformation ratios, magnetization curves corresponding to all secondary taps must be submitted with the tender. Secondary windings resistances at such secondary tap shall also be clearly specified. The secondary terminal box shall be provided with necessary glands with removable gland plate for control cables. The secondary terminal box shall conform to IP-55 test.

iv) Primary winding shall be made out of high conducting copper. The design density for

short circuit current as well as conductivity for primary winding shall meet the requirement of IS:2705/1992 or latest issue. However for primary winding current density corresponding to the rated short time current shall not exceed 160 Amps./Sq.mm for copper conductor. Suitably insulated copper wire of electrolytic grade shall be used for secondary winding. The tenderer should furnish details of primary winding e.g. Number of primary turns, cross-section, short time current density and normal continuous rated current density in the primary winding so as to meet the requirement of IS. Winding shall have high mechanical strength for safety against stress.

v) The shape of external metal parts shall ensure that rainwater runs off and there is no

stagnation. vi) The requirement of current transformers of all classes regarding their ratio error,

minimum keen point voltage, exciting current at knee point voltage, maximum resistance of secondary winding etc. shall have to be coordinated with the requirement of the protective relay and protecting scheme wherever required without any extra cost to the purchaser.

vii) The CTs shall be of robust design, tested quality and reliable in operation. Only pure

high-grade paper would evenly under controlled conditions and impregnated with mineral oil under vacuum shall be used for the main insulation.

1.05 FITTINGS & ACCESSORIES FOR CTs

The CTs shall be provided with the following fittings & accessories:-

1) 2 Nos. bimetallic terminal connector with each CT suitable for horizontal & vertical take-off. The thickness of bimetallic strip/sleeve shall be of min.2 mm.

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2) Oil level gauge. 3) Pressure release device if design recommended. 4) Expansion Chamber or suitable type of device for absorbing variation in volume of oil due to

change in temperature of oil. 5) Oil filling/ drain valve/ plug/ hole with sealing arrangement. 6) Lifting lugs/ holes. 7) Weather proof secondary terminal box fitted with hinged/ bolted door and complete with

terminals and short circuit arrangements. The secondary box hinged/ bolted door shall have sealing arrangement.

8) Two Nos. earthing terminals. 9) Name & Rating plate showing details of connection diagram.

1.6 GENERAL REQUIREMENTS OF 33 KV CTs

1.6.1 INSULATING OIL AND BUSHINGS:

The quantity of insulating oil for first filling of each instrument transformer and complete specification of the oil shall be stated in the tender. The oil shall conform to the requirements of latest issue of IS: 335. The instrument transformers shall be of standards duly filed in with oil. The oil filled bushing shall be of standard make such as W.S. Industries, BHEL/MIL/Birla NGK/CJI/TEKMEK, KOLKATA. The bushing shall be suitable for operation in heavily polluted atmosphere with creepage distance of minimum 25 mm per KV. The details of make and catalogue no. etc. of bushing shall be clearly stated in the guaranteed technical particulars. Pressure of nitrogen or any other inert gas used above the oil level to permit expansion or contraction of oil alongwith device to detect any leakage if any shall be stated in the tender.

1.6.2 TERMINAL CONNECTORS:

The Instrument transformers shall be supplied with bimetallic terminal connectors for both ends suitable for ACSR Panther conductor as per requirement and confirming to IS:5561. Each terminal connector shall be suitable for both horizontal and vertical take off arrangement.

The instruments transformers shall also be provided with two number earthing terminals of adequate size, protected against corrosion and metallically clean. Bimetallic strips or sleeves of suitable thickness to prevent bimetallic corrosion shall be provided as a part of the terminal connectors.

1.6.3 PAINTING:

All ferrous parts of the Instrument Transformers exposed to atmosphere shall be painted

externally with one coat of anti rust abide paint (Primer) and two coats of dark admirably grey paint

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(synthetic enamel paint of light grey shade No. 631 of IS:5). All interior surfaces in contact with oil

shall be painted with two coats of heat resistant oil insoluble paint.

1.6.4 TYPE OF MOUNTINGS:

The tenderer may submit their drawing / design for supporting structures of the Instrument transformers offered by bidders.

1.7 DRAWING AND MANUALS: The following drawings/ technical literature of the equipment covered by this specification shall be furnished along with offer: -

i. Outline general arrangement drawings showing all dimensions and weight of each item.

ii. Drawing showing inside details. iii. Diagram of connections and drawing for ratio plate. iv. Drawing of bushing insulator to be used mentioning all details. v. Drawings depicting magnetization curve for relevant secondary winding of the

Instrument Transformers vi. Technical and descriptive literature explaining constructional features and details

of the equipments. vii. Drawing of bimetallic terminal connector indicating all details. viii. Name/Rating plate diagram ix. Drawing of all fittings and accessories

1.08 INSTRUCTION MANUALS:

The successful tenderer shall have to supply 10 sets of operating and maintenance instruction manuals along with the erection manuals and requisite drawings of the equipments covered by this specification.One set of drawings and a manual shall also be sent along with each consignment to respective consignee.

1.9 NAME / RATING PLATE:

All items of the equipment includes in this specification shall be provided with rating plates as per relevant standards. Rating Plate & terminal marking shall be as per relevant IS. Purchase order / TN reference shall also be given.

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1.10 TYPE TEST REPORTS

Certified copies of tests reports from any CPRI/ NABL accredited testing laboratories of all type tests as per relevant latest standard mentioned under section-III clause 3.02 in respect of similar equipment (voltage class wise) included in this specification alongwith bushing and terminal connector (if offered other than approved make) shall be furnished to adjudge the technical suitability alongwith the tender. The tenderer shall furnish necessary calculations on the basis of STC test reports furnished above to prove the CTs of offered ratios are capable to withstand the specified short circuit level. The type tests reports shall not be older than 5 years. The type tests details are as under:

a) Short time current test b) Lightening impulse voltage withstand test. c) Temperature rise test. d) High voltage power frequency (wet) withstand test. e) Determination of errors or other characteristics.

1.11 TESTS AT SITE/ VERIFICATION AT STORES:

The purchaser reserves the right to carry out any site tests as he may decide at his own cost and will claim reimbursement from the supplier, in case the material as a result of such test / tests is not found conforming for the prescribed specification.

Verification:- One CT in each offered lot received in Nigam’s stores shall be opened for verifying the diameter and cross sectional area of primary conductor including verification of GTP. If CT fails in above verification at Stores, entire lot shall be rejected and supplier shall lift the rejected lot. In case it found within specified limit, the supplier at his own cost shall reassemble/ replace the physically opened CT at works/ stores.

The payment against supplies shall be released after obtaining successful store verification.

1.12 GUARANTEED TECHNICAL PARTICULARS:

Guaranteed technical particulars for Instrument Transformers is appended at Annexure-I .

1.13 MATERIAL AND WORKMANSHIP:

All materials used in the manufacture of aforesaid equipment shall be of best quality and capable of satisfactory operation under climatic conditions mentioned in Clause 1.02 above. The workmanship shall be of the highest grade and the practice.

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1.14 COMPLETENESS OF EQUIPMENTS:

All fittings, accessories or apparatus which may have not been specifically mentioned in this specification but which are usual or necessary for the equipments shall be deemed to have been included in this specification. All equipments shall complete in all respect.

31.15 LATENT DEFECTS, ERRORS AND OMISSIONS:

Any material / equipment or part thereof that developed defects, error or omissions in the apparatus, not disclosed prior to the final acceptance by the purchaser, but occur or are disclosed during the guaranteed period shall be corrected promptly or the apparatus or part there of shall be replaced by the supplier free of charges and all expenses for the transportation handling, installation of such replacement or any other incidental charges shall be borne by the supplier.

13.16 GUARANTEE PERIOD & REPLACEMENT DURING GUARANTEE PERIOD:

Performance guarantee of the equipment shall be for the period of 36 months from the date of receipt in stores. The month & year of expiry of guarantee period shall be marked on the nameplate. Equipment failed within such guarantee period shall have to be replaced free of cost within 45 days of intimation. You shall furnish successful routine test reports of the equipment. If purchaser desires inspection prior to dispatch an inspecting officer shall be nominated for verification for the test reports. Transportation and lifting of defective material & delivery of replaced material shall be borne by the supplier.

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ANNEXURE-I GUARANTEED TECHNICAL PARTICULARS FOR 33 KV SINGLE PHASE CURRENT TRANSFORMERS

S. No. Description Technical particulars

1 Name of Manufacturer & Country of Origin.

2 Manufacturer Type designation

a. Nominal system voltage.

b. Highest system voltages.

3 Class of Insulation

i. One minute Power Frequency withstand voltage (KVrms)

ii. Impulse withstand Voltage (KVP)

iii. One Minute High Voltage Power Frequency test

a. Primary winding

b. Secondary winding

4. Frequency.

5. Transformation ratio(s).

6. Rated Continuous thermal current rating (kA rms)

7. Rated Short time thermal current of primaryfor one second. (kA rms)

8 Rated Dynamic Current of primary (kA peak)

9 Temperature rise for rated continuous thermal current over an ambient temperature of 50 Deg. C at rated burden.

10 Core utilization for CTs having ratio

(a) 400-200-100/5-5 A (b) 240-120-60/5-5 A

CORE-I

CORE-II

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a. Rated Primary current (in Amp.)

b. Rated Secondary Current (in Amp.

c. Rated burden.

d. Class of Accuracy.

e. Max. Instrument Security Factor.

f. Accuracy limit factor.

g. Exciting Current.

h. Maximum resistance of secondary winding corrected to 75 Deg. C at lowest tap.

i. Core Material.

11. Winding Details Primary winding

Secondary Winding

a. Material of conductor.

b. No. of turns.

c. Cross sectional area.

d. Weight of winding.

12. Whether complete type test reports as per relevant IS enclosed.

13. Whether magnetization curve enclosed.

14. IS to which CT conform

15. Total weight of CT

16.a. Quantity of oil

b. Governing standard for oil

17. Overall dimensions.

18. Mounting details.

19. Bushing details.

a. Confirm to IS:

b. Make.

c. Catalogue No.

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d. Total creepage distance (mm)

e. Protected creepage distance.

20. Make of terminal connector

21 Whether pressure release device provided.

22. Other Characteristics

a Ratio and phases angle curve.

b. Ratio correction factor curve.

23. Current density in primary windings.

a Normal rating, Amps per Sq.mm

b. Thermal rating of 3 sec. Amps. per sq.mm.

c. Dynamic rating Amps. per sq.mm

24. Test results of oil as per IS:335

a Break Down Voltage

b. Tan delta at 90 Deg.

c. Colour of oil (shall be color less)

25 Any other specific feature.

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TECHNICAL SPECIFICATION AND OTHER REQUIREMENTS FOR HARDWARE FITTINGS FOR 11 KV,45 KN DISC INSULATORS

TONGUE & CLEVIS TYPE & HARDWARE FITTINGS 11 KV,45 KN DISC INSULATORS BALL & SOCKET TYPE

1.0 SCOPE : 1.1 This specification covers the design, manufacture, testing supply and

delivery of hardware fittings suitable for 11 KV disc insulators tongue & clevis type & Ball & Socket Type for use on various 11 KV /33KV sub transmission lines . These fittings are to be designed as per drawing attached at Appendix-I (A) & I(C) { for T&C type } and I (B) & I(C) {For B&S type}

1.2 The technical specifications, contained herein, are for the guidance of the

bidders 2.00 STANDARD :

Hardware fittings for 11 KV disc insulators T&C & B&S type should conform to

ISS:2486 (Part.I/1993), 2486 (Part.II) 1989, ISS:2486 Part.III / 1974 and ISS:2486(Part. IV), 1981.

3.1 GENERAL REQUIREMENT :

i) All forgings and castings shall be of good finish and free from flaws and

other defects. The edges on the outside of fittings, such as at the eye clevis and holes, shall be rounded.

ii) All parts of different fittings which provide for inter connection shall be made

such that sufficient clearance is provided at connection point to ensure free movement. All eye and clevis connections shall be free in this manner but care shall be taken that to much clearance between eye and tongues of the clevis is avoided.

(iii) All ferrous fittings and the parts other than those of stainless steel, shall be

hot dipped galvanized. Small fittings like spring washers, nuts etc. may be electroplated with zinc conforming to IS:1573:1970 Grade-4.

(iv) MATERIAL : The material of the fittings shall be so selected that yield

strength of the material shall not be less than maximum working load.

All fittings except strain clamp shall be made of drop forged or upset forged steel (IS-2004/1978) and shall be hot dipped galvanised.

The strain clamp for aluminium AAC and ACSR Conductor shall be high

strength Aluminium alloy (IS 6051/1970). The composition of the alloy shall be declared by the manufacturer giving reference to the relevant Indian Standard.

The cotter pins shall be provided with mild steel flat washers in addition to

split pins. The split pin to be used on the cotter pin shall be of phosphors-bronze

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conforming to IS-7814/1975, stainless steel conforming to IS-5522/1992, or brass conforming to IS-410/1977 with a minimum hardness of 160 HV.

MATERIAL FOR :

S. No. Description Particulars a) Dead end straps. Galvanised M.S.Twisted b) Strain bolts & nuts with spring washer Galvanised M.S. c) Cotter pin. Phospherbronze/Brass/

stainless steel. d) Special envelope for bolted type clamp Al.Alloy. e) Socket eye Forged steel f) Ball eye Forged Steel. g) Clevis ended strain clamp. Aluminium alloy

(v) Weight of T&C & B&S type hardware fittings set shall be indicated in GTP as per details below :-

S. No. Description “T&C” “B&S” i) Net weight per set in kg 1.250 3.350

ii) Net weight of steel parts in Kg.

1.050 2.675

iii) Net weight of Aluminium part per set in Kg.

0.200 0.675

3.1 TOUNGE AND CLEVIS TYPE HARDWARE:

Each T&C type hardware fitting set shall be complete in every respect and shall comprise of the following:

S. No. Description Particulars i) Dead end straps.(As per drawing

attached) One set.

ii) Strain bolt with hexgonal nuts. One No. iii) Spring washer One No iv) Flat washter One No. v) Cotter pin. One No. vi) Split pin One No vii) Clevis ended aluminium alloy clamps

suitable for ACSR conductor 7/2.11MM, 7/2.59 MM and 7/3.35 MM. Theultimate strength of clamps shall not be less than 3000 Kgs (As per drawing attached)

One No.

The T&C type fittings shall conform in all respect to drawing attached with the specification.(Appendix-I A&C)

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3.2 CLEVIS AND TONGUE CONNECTION :

The dimension of the tongue and clevis type connection shall conform to Fig 25 of ISS 2486 (Part-2)/1989.

3.3 BALL AND SOCKET TYPE HARDWARES :

Each B&S type hardware fitting set shall be complete in every respect and

shall comprise of the following :

S. No. Description Particulars i) Dead end straps.(As per drawing

attached) One set.

ii) Strain bolt with hexgonal nuts. One set. iii) Spring washer One set. iv) Ball eye. One set. v) Socket eye One set. vi) Split pin One set. vii) Flat washer One set. viii) Cotter pin One set. ix) Strain clamp of special envelops type

made of aluminium alloy (Bolted type).One set.

x) Security clips (W.type) Split pin shall not be accepted.

One set.

The dead end straps or cross arms straps shall comprise of a pair of twisted straps, one strain bolt with one spring washer and hexagonal nut and split pin. The strap shall conformed to drawing attached.(Appendix-1C)

The material for the hardware fittings shall be such that it gives the required mechanical strength with specified dimensions. The aluminium alloy of the clamp shall conform to A-6 of IS:617 and shall be gravity die cast.

All nuts shall be made of material conforming to properly class 5 of IS:1367:1967 with regard to its mechanical properties. Cotter pins shall be made of forged steel conforming to Clause No. 2 of ISS:2004:1962,IS- 2004:1978.

For galvanising, zinc conforming to grade Zn-98 of IS:209/1966,IS

209/1979 shall be used.

The B&S type fittings shall conform in all respect to drawing attached with the specification.(Appendix-I B&1C)

3.4 GALVANISING :

The uniforminty of zinc coating of hot dipped galvanised parts shall

conform to IS:2633:1972 with latest amendments thereof, if any.

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3.5 MARKING :

The clamps (aluminum portion) of each H/W fittings shall be provided with the following marking:

a) Name of manufacturer or trade mark. b) Year of manufacture.

The packages containing fittings may also be marked with the standard

mark, if available.

3.6 PACKING :

For packing double bags, one HDP bag (inner) and one gunny bag (outer) or double gunny bag shall be employed. The packing shall be fit to withstand rough handling during transit and storage at destination. The heads and threaded portions of the fittings shall be properly protected against damage. The gross weight of the packing shall not normally exceed 50 Kg. Different fittings shall be packed in different bags and shall be completed with their minor accessories fitted in place. All nuts shall be hand tightened over the bolts and screwed upto the farthest point.

3.7 DRAWINGS :

The Hardware fitting shall conform in all respects to drawing at Appendix-I A & IC for T&C type and Appendix IB & IC for B&S type Disc Insulators.

The bidder shall submit detailed drawing showing design and dimensions. The

type of material used for various parts shall be clearly specified on the drawing.

3.8 TYPE TESTS :

3.8.1 The bidder shall furnish valid and authenticated type test certificates from a Govt. approved / Govt. recognized / NABL Accredited laboratory / ILAC i.e. International Laboratory Accredited Laboratory (in case of foreign laboratory) of similar rating and design of tendered material/ equipment. Such type test certificates should not be older than 5 years as on the date of bid opening. For this purpose date of conducting type test will be considered.


3.8.2 The bidder should furnish documentary evidence in support of the laboratory whose type test have been furnished, that the said laboratory is a Govt. / a Govt. approved / a Govt. recognized / NABL accredited laboratory / ILAC accredited (in case of foreign laboratory).

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3.8.03 The type test certificates shall be furnished either in original or copy duly attested by notary.

3.9 ROUTINE AND ACCEPTANCE TESTS :

The material shall be subjected to all routine and acceptance tests specified in the latest edition of relevant IS, before dispatch. Such tests shall be witnessed by the inspecting officer from the purchaser's side.


The bidder must indicate clearly about the various testing facilities for type tests as well as routine/sample tests as per relevant ISS in respect of hardwares are available at the bidders works. In case no testing facilities are available at the bidders works, particulars of the place where such testing is proposed to be conducted during the course of inspection must be indicated.

3.11 VERIFICATION OF DIMENSIONS :

The following tolerances are allowed on all dimensions to which special tolerances do not apply :

Dimensions Tolerance Upto and including 35 mm (+/-) 0.7 mm

Over 35 mm (+/-) 2%


3.12.1 The material received in the NIGAM shall be subjected to the test checking before final acceptance of the material, the procedure for the same shall be as under :

3.12.2 SAMPLING

One sample out of each sub-lot / lot consisting of following quantities or part there of of hardware fittings for disc insulators from each inspected lot received in stores shall be selected for test checking of material and shall be got tested.

H/W fittings for 11 KV 45 KN Disc Insulator B&S type- 1000 Sets H/W fittings for 11 KV 45 KN Disc Insulator T&C type- 3000 Sets

The selection of sample from the material received at stores shall be done as soon as material is received in stores without the presence of the representative of the supplier. However, testing of sample(s) at CTL shall be carried out in the presence of representative of the supplier after identification / confirmation by him that sample so selected belongs to them. In case the supplier disputes that the selected samples does not pertain to them, then fresh sample shall be selected in the presence of the representative of the supplier and test(s) be carried out.

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3.12.3 TESTS


a) Visual Examination, Verification of Dimension, weight and marking Test b) Slip Strength Test. c) Ultimate Strength Test. d) Galvanisation (Uniformity) Test.

3.12.4 Testing of the material shall be got done at the test laboratory of the

NIGAM i.e. at CTL in the presence of the representative of the supplier. For witnessing of testing, clear 7 days notice shall be given to the supplier by fax / speed post stating date, time & place where the test is to be conducted. In case the supplier do not attend for witnessing the testing, the testing shall be proceeded and completed and action be taken as per the contract.

3.12.5 The witnessing officers of the NIGAM or as designated by the purchaser shall

send copies of test reports to the purchaser, consignees and the supplier. 3.12.6 Only those tests shall be conducted at CTL for which facility with CTL is

available.

3.13. CRITERIA FOR ACCEPTANCE

3.13.1 Visual Examination, Verification of Dimension, weight and marking Test As per specification/ ISS

3.13.2 Slip Strength test & Ultimate Strength Test :

In case of failure of sample in Slip Strength test or Ultimate Strength Test, the

material contained in the lot / sub-lot to which the sample belongs, shall be rejected. The rejected material shall have to be replaced by the supplier free of cost.

3.14.3 Galvanisation (Uniformity) Test.

i) The sample(s) shall be first tested for (n-2) number of dips where (n) is

specified number of dips in the contract. If the sample(s) does not pass the uniformity of Galvanisation Test for (n-2) dips, the material shall be rejected and the material relating to relevant lot / sub- lot to which sample(s) pertains shall have to be replaced by the supplier free of cost.

ii) If the sample has passed the uniformity of Galvanisation Test for (n-2)

dips, then it shall be tested for (n-1) dips. If the sample has not passed the uniformity of Galvanisation Test with (n-1) dips, then material pertaining to relevant lot / sub-lot shall be accepted with a deduction @ 10% of cost of material.

iii) If the sample has passed the uniformity of Galvanisation Test with (n-

1) dips, then sample shall be tested for last one dip of one minute to complete the test for `n' dips. If the sample does not pass the uniformity of Galvanisation Test with `n' dips, then the material pertaining to

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relevant lot/ sub-lot shall be accepted with a deduction @ 5% of cost of material.

iv) If the sample(s) have passed the Test with number of dips as specified in

the contract (n), then material pertaining to relevant lot / sub-lot shall be accepted.

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TECHNICAL SPECIFICATION AND OTHER REQUIREMENTS FOR HARDWARE FITTINGS FOR 120 KN DISC INSULATORS `B&S' TYPE

(BOLTED TYPE SINGLE TENSION CLAMP SUITABLE FOR ACSR `PANTHER' CONDUCTOR & LINKED WITH 120 KN DISC INSULATOR)

1.0 SCOPE :

This specification covers the design, manufacture, testing at manufacturer's

works before dispatch, supply and delivery of hardware fittings and accessories suitable for 120 KN Disc Insulators `B&S' type (Bolted type single tension clamp suitable for ACSR `Panther' conductor & linked with 120 KN Disc Insulators) for use on various 33 KV & 132 KV lines and Grid Sub Station .

2.0 STANDARDS;

This hardware fittings and accessories should conform in all respect to

the latest editions of IS-2486(PART.I/1993), (PART.II/1989) and (PART.IV/1981). All nuts shall be made of material conforming to property clause 4.8 of IS:1367/1967 (first revision) with regard to its mechanical properties, cotter pins should be made of forged steel conforming to clause 2 of IS:2004/1970 (first revision) with latest amendments. All ferrous parts shall be hot dip galvanized. Electro galvanised ferrous fittings shall be in accordance with IS:1573/1970 (first revision).

The hardware fittings are required to be used with Disc Insulators string

units containing insulators of type-B as classified under clause-5 "Classification" of IS:731/1971 and ACSR Panther conductor specified in IS:398/pt.II/1976.

3.0. GENERAL REQUIREMENTS :

i) The insulator strings hardware fittings shall be supplied complete in all

respect and shall include all fittings necessary for composing the insulator strings and should include shackles, U-clevis or ball-links for attaching it to the strain plate or hangers supplied with Sub-Station structures. Conductor strain clamps should be suitable for attaching the specified conductor to the string.

The supplier shall ensure that the insulator fittings offered are complete in all

respect and are entirely suitable for the proposed attachment and for the sizes of conductors indicated in Appendi

All Bolts , nuts & screw heals shall be of standard thread. Bolt heads and nuts shall be hexagonal. Where ever, required, nuts shall be locked in an approved manner. The threads in nuts and tapped holes shall be cut after galvanising and shall be well- lubricated greased. All other threads shall be cut before galvanising.

The bolt thread shall be under cut to take care of increase in diameter due to

galvanisation. ii) All forgings and castings shall be of good finish and free from flaws and other

defects. The edges on the outside of fittings, such as at the eye clevis and holes, shall be rounded.

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iii) All parts of Hardware fittings which provide for interconnection shall be made such that sufficient clearance is provided at connection point to ensure free movement and tension of the insulators string assembly. All eye and clevis connections shall be free in this manner but care shall be taken that too much clearance between eye and tongues of the clevis is avoided.

3.1 MATERIAL DESIGN AND TYPE :

i) The material for string insulator fittings (except those specified otherwise) shall

be either drop forged steel or heat treated malleable cast iron and shall be hot dip galvanised after all machining and fittings have been completed. The material used in fittings shall be corrosion resistant. All nuts shall be made of material conforming to property clause 4.8 of IS : 1367- 1967 (first revision) with regard to its mechanical properties and cotter pins shall be made of forged steel conforming to clause 2 of IS-2004-1970 with latest amendments.

The security clips shall be of phosphor bronze conforming to IS: 1385/1968 or of

brass of suitable temper with minimum hardness of 100 HV conforming to IS: 410- 1967 (second revision) with latest amendments. For galvanising, zinc conforming to grade zn 98 of IS:209/1966 shall be used.

ii) The locking devices shall be resilient, corrosion resistant, and of suitable

mechanical strength. The hardness and temper of the material are important for their satisfactory operation.

The locking devices shall retain their locking ability after being operated from the locking to the coupling position at least twenty times, at normal temperature. They should be effective at the lowest temperature likely to be encountered in service.

iii) All fittings shall be designed so that the harmful bimetallic corrosion is avoided and

effects of vibration, both on conductor and fitting itself are minimized. iv) TENSION CLAMP : The bolted type clamps shall be made out of high

strength aluminum alloy suitable for Panther conductor indicated in Appendix-I. The mechanical efficiency of tension clamps shall not be effected by method of erection involving "Come-Along" or similar clamp during or after assembly and erection of tension clamp itself. The strain clamp shall have the same conductivity as the conductor, and shall be of a design that will ensure unrestricted flow of current.

3.2 ATMOSPHERIC CONDITIONS :

The material offered shall be suitable for operation in hot and humid

tropical climate and will be subject to inclement weather and shall be able to withstand vide range of temperature variation. The humidity may be as high as 90% during rainy season and as low as 10% during the dry season.

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3.3 DRAWING :

The bidder should submit detailed drawing showing design and dimensions of the complete hardware set alongwith design and dimension of various parts. Full particulars of the conductor clamps shall be given and the type of material used of various parts should be clearly specified either on the drawing or in a separate statement.

THE BID DRAWINGS SHOULD CONSIST OF :

i) Dimensioned assembly drawings of the complete hardware set with all fittings.

ii) Separate detailed dimensioned drawing for all hardware fittings such as conductor, tension clamps, hook ball clevis socket clevis, yokes etc.

iii) Weight of Alluminium and steel portion separately.

3.4 GUARANTEED TECHNICAL PARTICULARS :

The number of discs used on tension strings and the EMS ratings, technical particulars of matching insulators and that of conductor are given in Appendix -I.

3.5 TEST CHECKING OF MATERIAL AT STORES 3.5.1 The material received in the NIGAM shall be subjected to the test checking at stores before final acceptance of the material, the procedure for the same shall be as under :

3.5.2 SAMPLING

One sample out of each sub-lot / lot consisting of 500 sets or part thereof of

hardware fittings for disc insulators from each inspected lot received in stores shall be selected for test checking of material and shall be got tested.

The selection of sample from the material received at stores shall be done as soon as material is received in stores without the presence of the representative of the supplier. However, testing of sample(s) at CTL shall be carried out in the presence of representative of the supplier after identification / confirmation by him that sample so selected belongs to them. In case the supplier disputes that the selected samples does not pertain to them, then fresh sample shall be selected in the presence of the representative of the supplier and test(s) be carried out.

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APPENDIX - I

TECHNICAL REQUIREMENT FOR BOLTED TYPE HARDWARE FITTINGS 132 KV STRING INSULATOR HARDWARE

1. Power system 132 KV 3 Phase 50 Cycles Effectively earthed.

2. Insulators :

Type Conventional ball & socket type Diameter 255 mm Spacking 145 mm Colour Brown Surface Glazed i) Highest system voltage 145 KV(rms) ii) Visible discharge test(power

frequency voltage) 105 KV(rms)

iii) Wet power frequency with stand test.

230 KV(rms)

iv) Impulse voltage Withstand test. 550 KV(Peak)

v) power frequency puncture withstand voltage.

1.3 times the actual dry flashover voltage.

vi) Minimum creepage distance of the insulator for moderately polluted atmospheres (total).

2250 mm.

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APPENDIX-II

MECHANICAL REQUIREMENT FOR BOLTED TYPE HARDWARE FITTINGS

1 Strings arrangements Nos. of Disc Electro Mechanical strength

a) Tension strings for normal tension locations

10 120 KN

b) Minimum Failing load. As above.

2 Accessories & Hardwares

(A) 132 KV Power Conductor Hardwares :

a) Clamps Tension

Slip strength (Max.) 8230 Kgs.

Ultimate strength. 9144 Kgs.

Minimum failing load 9144 Kgs.

b) Other Hardware

Minimum failing load 9144 Kgs.

c) Conductor ACSR Panther

d) Stranding & wire diameter Al 30/3.04 + St7/3.0 mm

e) Approx. overall dia 21.0 mm

f) Normal area 207 mm sq.

g) Maximum temp. of conductor carrying current & expose to sun.

67 degree C

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TECHNICAL SPECIFICATION OF REQUIREMENT FOR SUPPLY OF ISI MARKED VARIOUS SIZES OF FOUR CORE LT XLPE INSULATED AND PVC SHEATHED ARMOURED CABLES.

1. SCOPE:

This section provides for manufacture, testing before dispatch and supply of ISI Marked various sizes of Four Core LT XLPE Insulated and PVC Sheathed Armoured Circular Cables with Aluminium Conductor suitable for working voltage up to & including 1100 Volts & Conforming to IS:7098(Pt.-I)/1988 with latest amendments. The cables shall be ISI marked.

2. STANDARDS:

Unless otherwise stipulated in this specification the following standards with latest

amendments shall be applicable.

i) IS:7098(Pt-.I)/1988 : XLPE Insulated cables for working voltages up to and including 1100 Volts.

ii) IS:8130 : Conductors for insulated

cables.

iii) S:5831 : PVC insulation and sheath of electric cables.

iv) IS:10810 : Methods of test for cables.

v) IS:3975/1979 : Galvanized Steel Wire/Strips.

vi) IS:10418 : Drums for electric cables. 3. CLIMATIC CONDITIONS:

i) Peak ambient temperature in shade 50 deg.C

ii) Maximum average ambient 40 deg.C

temperature in a 24 hours period in shade.

iii) Min. ambient air temperature in shade (-)5 deg.C

iv) Maximum temperature attainable 60 deg.C

by an object exposed to sun.

v) Maximum relative humidity. 100%

vi) Average number of thunder 40 storm days per annum.

vii) Average number of rainy days 100

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per annum.

viii) Average annual rainfall 10 to 100 cm

ix) Number of months of tropical 4 months monsoon conditions.

x) Maximum wind pressure. 100kg/sq.mm.

xi) Altitude not exceeding 1000 M

4. GENERAL REQUIREMENT: 4.1 The LT XLPE Insulated

Armoured cables shall

conform to IS:7098

Pt.-I)/1988 with latest amendment and bear BIS certification mark. The material used for construction of the cables shall be of best qualities complying with the requirements of IS:7098(Pt-.I)/1988 and other relevant standards. The cables shall be suitable for outdoor / indoor installation free in air and shall be capable of withstanding the normal stresses associated with transportation, erection, reeling and unreeling operations without getting deformed.

4.2 The cable shall be suitable for use where combination of ambient temperature temperature rise due to load results in a conductor temperature not exceeding 90 degree C under normal operation and 250 degree C under short circuit condition.

4.3 The LT XLPE Insulated Armoured Cable shall be ISI marked.

The firms having ISO: 9001 will be preferred. 5.1 MATERIAL:

5.2 CONDUCTOR:

conductor shall be composed of plain aluminium wires complying with IS:8130/1984 with latest amendments.

The bidder must guaranteed the minimum weight of Aluminium in Kg/Km

corresponding to nominal cross sectional area of conductor as mentioned in the G.T.P.

5.3 INSULATION:

Insulation shall be Cross-Linked Polyethylene (XLPE) conforming to the

requirements given in Table-I of IS: 7098(Pt.-I)/1988 with latest amendments.

5.4 FILLERS:

5.4.1. The filler shall be of vulcanized rubber, un-vulcanized rubber, Thermoplastic material or textile material and shall be provided to fill the gaps between cores.

5.4.2. The filler materials shall be so chosen so as to be compatible with

temperature of the cable and shall have no deleterious effect on other components of the cable. These shall not be harder than XLPE and PVC used for insulation and outer sheath respectively.

396

5.3.3 The Central hole/void, if any, of the cable shall be invariably filled with suitable filler material so that there is no gap in the center.

5.4 ARMOURING :

Armouring shall be galvanized round steel Strip.

5.5 OUTER SHEATH:

outer sheath shall consist of type ST-2 PVC Compound conforming to the requirements of IS:5831/1984.

6. CONSTRUCTION:

6.1 CONDUCTOR:

construction of the conductor shall be as per Clause No.8.1 of IS:7098 (Pt-.I)

/1988 & relevant clause of IS:8130/1984 for all sizes of cable.

A protective barrier may be applied between the conductor and insulation. Such barriers when used, shall be compatible with insulating material and suitable for the operating temperature of the cable. 6.2 INSULATION:

The conductor (with protective barrier, wherever applied) shall be provided with Cross-Linked Polyethylene (XLPE) insulation applied by extrusion. The insulation shall be so applied that it fits closely on the conductor and it shall be possible to remove it without damage to the conductor. The thickness and tolerance on thickness of insulation shall be as per Clause No.9.2 of IS:7098(Pt-.I)/1988.


The core shall be identified by different colouring of XLPE insulation as per Clause

No.10.1 of IS:7098(Pt.-I)/ 1988.

6.4 LAYING UP OF CORES: The cores shall be laid up together with the suitable right hand lay. The interstices

shall be filled with non-hygroscopic material.


6.5.1 The laid up cores shall be provided with an inner sheath applied either by extrusion or by wrapping. However, application of inner sheath by EXTRUSION shall be preferred. It shall be ensured that it is as circular as possible. The thickness of inner sheath shall be as given in Table-5 of IS:7098(Pt.-I)/1988.

6.5.2 The inner sheath shall be so applied that it fits closely on the laid up cores

and it shall be possible to remove it without damage to the insulation.

6.6. ARMOURING :

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6.6.1 Application:- Armouring shall be applied over the inner sheath. The armour Strip shall be applied as closely as possible with a coverage of not less than 90%.

6.6.2 The direction of lay of armour shall be left hand. A Binder Tape may be

provided on the armour.

6.6.3 Type of Armour & Dimension :- The armour shall consist of galvanized strips for all sizes with the dimensions as specified in Table-6 of IS:7098(Pt- .I)/1988.

6.6.4 Joints:- The joints in the armour Strips shall be made by brazing or

welding and the surface irregularities shall be removed. A joint in any strips shall be at least 300 mm. from the nearest joint in any other armour strip in the completed cable.

6.7 OUTER SHEATH:

6.7.1 The outer sheath shall be applied by extrusion over armouring.

6.7.2 The colour of the outer sheath shall be black. 6.7.3 The minimum thickness of PVC outer sheath shall not fall below the nominal

thickness ( ts ) specified in Table-8 of IS:7098(pt.I/1988. 7. TESTS AND TEST CERTIFICATES:

7.1 The cables should meet the requirement of all tests including optional tests

as specified at Clause No.15.4 of IS:7098(Pt.1)/1988.

The following shall constitute Routine Test:

7.1.1 Conductor resistance test. 7.1.2 High Voltage test.

The following shall constitute Acceptance Tests:

i) Tensile test (for Aluminium).

ii) Wrapping test (for Aluminium). iii) Conductor resistance test. iv) Test for thickness of Insulation & Sheath. v) Hot Set Test for Insulation.

vi) Tensile strength & elongation at break of insulation & sheath. vii) Insulation resistance (Volume Resistivity)test. viii) High Voltage test. xi) Test for Armour:

g) Verification of Dimension of Wire / Strip. h) Tensile Strength & elongation at break. i) Uniformity of Zinc Coating. j) Weight of Zinc Coating. k) Winding Test on Armour. l) Resistivity Test on Armour.

398

The following shall constitute Optional Tests:

i) Cold Bend Test for outer sheath.

ii) Cold Impact Test for outer sheath. The following shall constitute Type Tests:


i) Tensile test (for aluminium) ii) Wrapping test (for aluminium) iii) Conductor resistance test.

b) Test for Armouring Wire / Strip.

c) Tests for thickness of insulation and sheath.

d) Physical tests for insulation:

i) Tensile strength and elongation at break. ii) Ageing in air oven. iii) Hot Set test. iv) Shrinkage Test v) Water Absorption (Gravimetric).

e) Physical tests for Outer Sheath:

i) Tensile strength and elongation at break. ii) Ageing in air oven. iii) Loss of mass in air oven. iv) Shrinkage Test. v) Hot Deformation Test. vi) Heat Shock Test. vii) Thermal Stability.

f) Insulation resistance (Volume Resistivity test)

g) High voltage test.

h) Flammability test.

i) Any other test as per relevant ISS.

7.2 TYPE TESTS : 7.2.1 The material offered, shall be fully type tested as per relevant standard of

specification of IS:7098 (Part.1/1988) amended up to date. The bidder must furnish type test reports of similar rating & design of material as detailed at scheduled -A

7.2.2 The bidder must also clearly indicate various testing facilities available at their works for testing the material as per relevant standards. In case of otherwise

399

particulars of the place where such testing in proposed to be conducted during the course of inspection shall be indicated with the offer.

7.2.3 However, the purchaser reserves the right to demand repetition of same or all the

type tests in presence of purchaser’s representative.

7.2.4 The bidding firms (manufacturers) must have valid ISI license for the offered cable. The bidder shall furnish the details of ISI License granted to them.


8.1 The inspection may be carried out by the purchaser at any stage of manufacturer. Acceptance of any equipment / material under this specification by the purchaser shall not relieve the supplier of his obligation of furnishing equipment in accordance with the specification and shall not prevent subsequent rejection if the equipment/material is found to be defective.

8.2 The supplier shall keep the purchaser informed in advance about the

manufacturing program so that arrangement can be made for inspection.

8.3 The acceptance tests as per IS:7098(Pt.I)/1988 shall also be conducted by the manufacturer before dispatch in the presence of our Representative/Inspecting Officer along with verification of lengths & weight and checking the manufacturing defects, if any of samples coils. The mass of Aluminium, XLPE, PVC & Filler in sample coils shall also be verified by the Inspecting Officer(s).

Cold bend/ cold impact test (IS:5831/1984) shall constitute the optional tests and

shall be conducted on first lot and any from other lot of the offered cables of each size as per Clause No.15.4 of IS:7098(Pt-.I)/1988.

8.4 The purchaser reserves the right to insist or witnessing the acceptance/routine tests of the bought out items.

8.5 The bidder shall furnish Packing list mentioning serial Nos. of Drums, length in each drum, gross weight of drum without lagging alongwith inspection offer duly signed by the authorized representative of the firm. The purchaser reserves the rights to insist for witnessing the acceptance / routine tests of the bought out items.

8.6 At least 5% of total numbers of drums subject to minimum of 2 in any lot put up for inspection shall be selected at random to ascertain the length/ workmanship of cable by the following method :

“At the works of the manufacturer, the cable shall be transferred from one drum to another for checking any manufacturing defects in the cable drums selected for conducting acceptance tests, at the same time measuring its length with the help of the graduated pulley & cyclometer. The difference in the average length thus obtained from the declared length by the supplier in the packing list shall be applied to all the drums if the cable is found short during checking the sample lot(s)”.

400


The calibration certificate(s) should not in any case be older than one year at the time of presenting the same to the inspecting officer/ inspecting agency of the purchaser. The testing instruments/ equipments should be duly sealed by the Calibrating Agency and mention thereof shall be indicated in the calibration certificate(s).

9. TEST CHECKING OF MATERIAL AT STORES:

(i) Sample drums from the material received at stores shall be selected for testing at CTL as per sampling plan given hereunder in presence of firm’s representative. The selected sample drum / drums shall be transported to CTL by concern S.S / ACOS of Nigam.

(ii) The selected sample drum for CTL testing shall be identified by the seals


(iii) The tests in the Nigam Testing laboratory (CTL) shall be conducted in the presence

of representative of supplier for which a 7 days notice shall be issued through Fax / Speed Post stating Date & Time to the firm, so that supplier can depute their representative to witness the test . In case the supplier or his representative does not turn up the testing shall be proceeded & completed. The payment shall be released only after receipt of successful test reports for the samples selected at purchaser’s stores for mandatory test checking on the samples to be selected from material received at Nigam’s stores by random sample selection by the authorized committee as per CE(MM) order No.180 dt.11.4.

iv) SAMPLING:

One number Drum out of each lot / sub-lot of 25 Nos. Drums or part thereof for the material received in Stores of Nigam.

v) TESTS: The following tests shall be carried out as per relevant clause of latest IS on each selected drum by drawing sample of 10 Mtr. at CTL from random distance during rewinding:

a) Rewinding test (Measurement of Length) & Checking of Manufacturing defects. b) Measurement of Resistance of conductor.

401

c) Tensile strength & Elongation at Break Test for Insulation & Sheath d) Test for Thickness of Insulation & Sheath e) Hot Set Test f) Test for Armour:

i) Verification of Dimension of Wire / Strip. ii) Tensile Strength & elongation at break. iii) Uniformity of Zinc Coating. iv) Weight of Zinc Coating. v) Winding Test on Armour. vi) Resistivity Test on Armour. vii) Verification of armouring coverage i.e.not less than 90%



vi) CRITERIA FOR ACCEPTANCE:

a) If the measured conductor resistance of the sample(s) exceeds beyond 2% as per the resistance specified in the contract, the material shall be rejected and the same shall have be replaced by the supplier.

b) If the measured conductor resistance of the sample(s) exceeds the

value specified in the contract but does not exceed by more than 2% of the resistance value specified in the contract, the material pertaining to the relevant lot / sub-lot to shall be accepted with a deduction @ 1.5% of the cost of cable for increase in resistance for every 1% or part thereof.

c) If the sample(s) fails in any other test, the material contained in the

pertinent lot/sub-lot shall be rejected and shall have to be replaced by the supplier.

d) If the contractor / supplier fails to lift the material declared rejected or

any part thereof from the consignee within a period of 15 days from the date of dispatch of information from the purchaser, the purchaser shall be entitled to effect recovery along with other actions

e) The results of measurement of length test shall be made applicable to all

drums contained in each lot / sub lot by making deduction of less length of cable in a Sample Drum.

10. TEST CHARGES : All test charges incurred towards test checking of the material received in our stores


11. IDENTIFICATION:

402

11.1 The manufacturer shall be identified through-out the length of cable as per Clause No.17.1 of IS:7098(Pt-I)/ 1988.

11.2 In order to distinguish these electric cables from telephone cables the word

ÈLECTRIC' shall be indicated, printed or embossed throughout the length of the cable on outer sheath.

11.3 The cable code shall be used as per Clause No.17.3 of IS:7098(Pt-.I)/1988.

11.4 The cable shall also be required to be embossed with the word ` Name of

Manufacturer or trade name, Cable code, Voltage Grade, NAME OF DISCOM / TN, size of cable & year of manufacture' at every meter length for which no extra charges shall be paid. The cable should be ISI marked & same should be embossed on the outer sheath of every meter of length of cable.

12. MARKING:

The progressive length of cable shall be marked on the outer sheath of every

meter length of cable.

13 PACKING AND MARKING:

13.1 The cables shall be wound on non-returnable wooden drums conforming to IS:10418/1982 of suitable size and packed. The ends of the cable shall be sealed by means of non-hygroscopic sealing material. Only one cable length shall be supplied on a drum. The shaft diameter of Drum shall be as per relevant ISS but not less than 50 mm. The cable can also be supplied on M- Steel Drums as per relevant ISS as applicable.

13.2 The cable shall carry the following information stenciled / painted on the drum :

i) Manufactuer's name, Brand name or trade mark. ii) Type of cable and voltage grade.

iii) Number of Cores. iv) Nominal Cross-sectional area of the conductor. v) Cable Code. vi) Length of cable on the drum.

vii) Approximate gross weight. viii) Year of manufacture. ix) BIS Certification mark. x) Name of the Consignee and full destination. xi) Bid number/Purchase Order No.

xii) The word SUITABLE FOR OUTDOOR USE & LOW TEMPERATURE CONDITIONS.

1 4 STANDARD LENGTH: 14.1 The cables shall be supplied in the standard length of 250 Meters for size

4CX400 Sqmm , 4CX300 Sq.mm and 4CX185 Sqmm & 500 Meters for 4Cx120 Sq. mm, 4CX95 Sqmm and 4CX70 Sqmm.

14.2 A tolerance (+/-) 5% shall be allowed in standard length.

403

14.3 Only one cable length shall be acceptable by non-standard length measuring not less than 50% of standard length to complete the ordered quantity in each size.

15 QUANTITY:

a) The quantities as mentioned in the schedule of requirement are tentative & these may increase/decrease as per the requirement of the Nigam (Schedule-I).

b) Details of offered quantity alogwith justification with reference to Qualifying

Requirement shall be furnished in Schedule-IV A.

16 QUANTITY TOLERANCE:

supply.

quantity tolerance of (+/-) 2% shall be allowed in each size for completion of

17 GUARANTEED TECHNICAL PARTICULARS: The bidder shall furnish guaranteed technical particulars in the relevant

Schedule VA & VB.

18 DRAWINGS & DOCUMENTATIONS:

The bidder is required to furnish the detailed constructional drawings of clearly showing shape of Core, Type, Size of Fillers / Interstices along with Center Filler etc. The calculations of weight of different components of the cable shall also be furnished. In absence of this, the bids are likely to be ignored. The drawings of drums shall also be furnished as per relevant applicable ISS.

404

Schedule-A

TYPE TEST CRITERIA:- 3.01 The bidder shall furnish valid and authenticated type test certificate from a Govt.

approved / Govt. Recognized / NABL Accrediated laboratory / ILAC i.e. International laboratory Accrediation Corporation (In case of foreign laboratory) / of similar rating and design of tendered material / equipment. The bid of the bidder be also considered for meeting the Type Test criterion if the bidder have the requisite Type Test conducted successfully on the samples selected from the 1st lot supplied to JVVNL against previous tenders and furnish certified copy of such Type Test Reports with the Bid. Such type test certificate should not be older than five years as on the date of bid opening For this purpose date of conducting type test will be considered.




405

Schedule-VA

GUARANTEED TECHNICAL AND OTHER PARTICULARS FOR THE SUPPLY OF 4 CORE LT XLPE ARMOURED CABLES

S. P A R T I C U L A R S UNIT 4 CORE XLPE ARMOURED CABLES IN SQ.MM

NO.

4CX400 4CX300 4CX185 4CX120 4CX95 4CX70

1 Manufacturer's name and works

address

2

Standard specification to which

IS:7098(Part-I):1988 with latest amendment

the material shall conform.

3 VOLTAGE GRADE 1100V

4

NO. OF CORES

(4C) (4C)

5

CONDUCTOR DETAILS :

a) Nominal cross section area of :

I ) Phase Conductor(sq.mm) 400 300 185 120 95 70

ii) Neutral Conductor (Sq.mm.) 400 300 185 120 95 70

b) No.and size of strands(in mm) of :

I) Phase Conductor(sq.mm) As per IS-8130/1984 with latest amendments

ii) Neutral Conductor (Sq.mm.) As per IS-8130/1984 with latest amendments

c) SHAPE OF CONDUCTOR To be furnished by the bidder

d) Whether compacted or non compacted

To be furnished by the bidder

e) Resistance

I) Phase Conductor(sq.mm) 0.0778 0.100 0.164 0.253 0.320 0.443

ii) Neutral Conductor (Sq.mm.) 0.0778 0.100 0.164 0.253 0.320 0.443

6

INSULATION

I) Type XLPE As per IS:7098(Part-I):1988 with latest amendment

ii) Colour R,Y,B & neutral Black

406

iii) Thickness

A) Phase Conductor(sq.mm) As per Table - 3 of IS-7098 (Part-I):1988 with latest amendments

a) Nominal (mm)

b) Minimum (mm)

B) Neutral Conductor (Sq.mm.) As per Table - 3 of IS-7098 (Part-I):1988 with latest amendments

a) Nominal (mm)

b) Minimum (mm)

7

Inner Sheath:

a) Material & Colour

To be furnished by bidder

b) Process of Application To be furnished by bidder

c) Minimum thickness of inner sheath As per Table - 5 of IS-7098 (Part-I):1988 with latest amendments

8 Whether Binder Tape provided As per IS:7098(Part-I):1988 with latest ammendment

9

Armouring

As per IS:7098(Part-I):1988 with latest ammendment

I) Material

ii) Nominal Dimension of Armour

iii)Whether galvanised or not

iv) Total number of Armour strips

10

Outer Sheath

I) Material Extruded PVC ST-2 type as IS 5831:1984 with latest ammendment

ii) Thickness As per Table - 8 of IS-7098 (Part-I):1988 with latest amendments

a) Nominal (mm)

b) Minimum (mm)

iii) Standrad to which it conform As per IS:7098(Part-I):1988 with latest ammendment

11 a) Type and size of filler used As per IS:7098(Part-I):1988 with latest ammendment

b) MIN. WT.OF FILLER IN KG./KM. To be furnished by bidder

12 MAX.OVERALL DIAMETER OF THE CABLE IN MM.


13 Nature of Packing Wooden drum

14

TARE WEIGHT OF DRUM


407

15

a) Minimum weight of Aluminium in Kg./Km. corresponding

4325 3244 2000 1297 1027 757

to nominal cross sectional area of conductor.(guaranteed)

b) Total weight armouring Kg/ Km. To be furnished by bidder

c) Total weight of PVC contents Kg/ Km.


(Inner / Outer Sheath / Filler)

d) Total weight of XLPE in Kg./Km.(Min.)


e) Total weight of finished cable Kg/Km. To be furnished by bidder

16

i)Standard length of cable

Metre

250 m 250m 250m 500m 500 m 500m

ii)Tolerance.On Standard length (+/-)5%

17

Whether material bears BIS certification mark

YES , ISI MARKING embossed on outer sheath

18 BIS licence no. & validity To be furnished by bidder

19 Embossing As per specification of TN:

20 Any other particulars

408

Schedule-VA

GUARANTEED TECHNICAL AND OTHER PARTICULARS OF DRUM FOR SUPPLY OF

FOUR CORE LT XLPE INSULATED ARMOURED CABLES

S. No.

P A R T I C U L A R S

4 CORE XLPE ARMOURED CABLES IN SQ.MM

4CX400 4CX300 4CX185 4CX120 4CX95 4CX70

A Drum Size

B Flange Diameter(d1) (mm)

C Barrel Diameter(d2) (mm) AS PER IS:10418/1982 WITH LATEST AMENDMENTS

D Centre hole Diameter(d3) (mm)

E Overall width (L1) (mm)

F Traverse (L2) (mm)

G Thickness of Flange

H

Barrel End (supporting disc

or core segment)

a) Diameter (mm)

b) Thickness (mm)

I

Stretchers( Core Carrier Planks)

a) Number (Min)

b) Thickness x width (mm)

J

Barrel Battens thickness

(Core Filler Planks)

K

Barrel Middle Supports

(Middle Core discs)

409

L

Thickness of External Laggings.(mm)

DETAILS OF METAL COMPONENTS:

M Clamping Studs with Hexagonal Nuts

a)

Numbers

b) Diameter (mm)

N

Square or Round Washers

a) Numbers

b) Diameter (mm)

O

M.S. Bushes

a) Numbers

b) Thickness of Sleeve (mm)

c) Dimension of Sleeve (mm)

d) Number of Bolts

e) Diameter of Bolts

P

M.S./ C.I. Centre Plate

a) Numbers

b) Dimensions of Square/

Triangular equal sides (mm)

c) Centre Plate Bolts.

Q Numbers

i) Diameter of bolts (mm)

ii) Centre Hole Diameter (mm)

410

TECHNICAL SPECIFICATION AND SCHEDULE OF REQUIREMENT FOR SUPPLY OF 33KV CROSS-LINKED POLYETHYLENE (XLPE) INSULATED POWER CABLES

1. SCOPE:

1.1 This section provides for manufacture, testing before dispatch and supply of

ISI Marked 33 KV Aluminium conductor Screened, Cross linked Polyethylene (XLPE) Insulated Armoured Shielded PVC Sheathed cable of rated voltage 33KV (earthed system) conforming to IS:7098 (Part-II/1985) with latest amendment.

The 33 KV Aluminium Conductor, Screened CROSS-LINKED POLYETHEYLENE (XLPE) INSULATED Armoured Shielded PVC Sheathed Power cable shall be ISI marked. The bidder should be a manufacturer of tendered item. The offers from Sole Selling Agents / Authorized Dealers shall not be entertained.

NOTE:-

The Manufacturer shall manufacture the 33 KV Power Cable with CCV Line Process only and offer from other type of manufacturing process (Syoplas) shall not be considered.

The bidder must possess valid ISI License for the bid item. The firm must possess

ISO-9001 or above certification.

2. STANDARDS:

Unless otherwise stipulated in this specification the following standards with latest amendments shall be applicable.

i) IS:7098(Part-II) : Cross linked Polyethylene Insulated PVC sheathed cable for voltage from 3.3 KV upto & Including 33 KV.

ii) IS:8130 : Conductors for insulated Cables.

iii) S:5831 : PVC insulation and sheath of

Electric cables. iv) IS:3975 : Mild steel wires, strips and

tapes for armouring cables.

v) IS:10810 : Methods of test for cables.


3. GENERAL REQUIREMENT:

3.1 The 33 KV power cable shall be ISI Marked Aluminium conductor screened cross linked polyethylene insulated armoured shielded and over all PVC sheathed. The 33 KV XLPE Cable shall conform to IS: 7098 (Part-II)/1985

411

with latest amendments shall bear ISI Certification mark. The cable shall be capable of withstanding the normal stresses associated with transportation, erection, reeling and unreeling operations without getting deformed.

3.2 The 33KV XLPE Cable shall be suitable for the following conditions of laying:

i) Laid directly in ground. ii) Installed outdoor in free air in vertical position.

iii) Drawn into underground ducts.

3.3 The 33 KV XLPE Power Cable shall be suitable for use where combination of ambient temperature and temperature rise due to load results in conductor temperature not exceeding 90 degree C. under normal operation and 250 degree C under short circuit conditions.

3.4 The cable shall be used on 33 KV earthed system. The cables shall be

suitable for continuous operation at a power frequency voltage 10% higher than rated voltage.

4.1 MATERIAL:

4.2 CONDUCTOR: The conductor shall be composed of aluminium wires complying with the requirement of Class-2 of IS: 8130/1984.

The bidder must guaranteed the minimum weight of Aluminium in Kg/Km

corresponding to nominal cross sectional area of conductor as mentioned in the G.T.P.

4.3 INSULATION:

The insulation shall be cross linked polyethylene conforming to the

requirement given in Table-1 of IS:7098(Part-II)/1985.

4.4 SCREENING:

The screening shall consist of one or more of the following:

iii) Non-Metallic semi conducting tape. ii) Non-Metallic semi conducting compound and iv) Non-Magnetic Metallic tape wire, strip or sheath.

4.5 FILLERS AND INNER SHEATH:

4.5.1 The filler and inner sheath shall be of the following:

b) Vulcanized or Un-vulcanized rubber or

b) Thermoplastic material.

4.5.2 Vulcanized or Un vulcanized rubber or Thermoplastic material used for

inner sheath shall not be harder than XLPE and PVC used for insulation and outer sheath respectively. The filler and inner sheath material shall be

412

chosen to be compatible with the temperature rating of the cable and shall have no deleterious effect on any other components of the cable.

4.5.3 The Central hole / void, if any, of the cable shall be invariably filled with

suitable filler material so that there is no gap in the center.

4.5 ARMOURING:

4.5.1 The Armouring shall be of Galvanized Steel Strip.

4.5.2. Galvanized steel strips shall comply with the requirements of IS:3975/1979 with latest amendments.

4.6 OUTER SHEATH:

4.6.1 The outer sheath shall be of Poly Vinyl Chloride (PVC) compound conforming to

the requirement of type ST-2 of IS:5831/1984.

5. CONSTRUCTION:

5.1 CONDUCTOR:

The Conductor shall be of stranded construction complying with Class-2 of IS:8130/1984. The aluminium shall be reasonably uniform in size and shape and its surface be free from any sharp edges.

5.2 CONDUCTOR SCREENING:

The conductor screening shall be provided over the conductor by applying non- metallic semi conducing tape or by extrusion of semi conducting compound or a combination of the two.

5.3 INSULATION:

The Conductor (with screen) shall be provided with cross linked polyethylene (XLPE) insulation applied by extrusion. The insulation shall be so applied that it fits closely on the conductor (or conductor screening) and it shall be possible to remove it without damaging the conductor. The thickness of insulation and tolerance of thickness of insulation shall be as per Clause No.11 of IS: 7098 (Part-II)/1985.

5.4 INSULATION SCREENING:

5.4.1 The insulation screening shall consist of two parts namely metallic and

non-metallic.

5.4.2 Non-metallic part shall be applied directly over the insulation of each core and shall consist of either a semi conducting tape or extruded semi conducting or a combination of the two or either material with a semi conducting coating.

413

5.4.3 Metallic part shall consist of either tape or braid or concentric serving of wires or a sheath should be non-magnetic and shall be applied over the non metallic part.


The core identification shall be done as per Clause-13 of IS:7098 (Part-II)/ 1985.

5.6 LAYING UP OF CORES:

The Cores (with screening) shall be laid together with a suitable right hand lay. Wherever, necessary the interstices shall be filled with non-hygroscopic material.


The laid up core shall be provided with inner sheath applied either by extrusion or by wrapping. However, application of inner sheath by EXTRUSION shall be preferred. It shall be ensured that the shape is as circular as possible. The inner sheath shall be so applied that it fits closely on the laid up cores and it shall be possible to remove it without damage to the insulation. The thickness of inner sheath shall be as per Clause No.15.3 of IS: 7098 (Part-II)/ 1985 (with latest amendments)

5.8 ARMOURING:

The armouring shall be applied over the inner sheath. The Galvanized Steel Armoured strips shall be applied as closely as possible with a coverage of not less than 90%.

The direction of lay of the Armour shall be left hand. A binder tape may be applied on the armouring. The dimensions of the galvanized steel strips shall be as specified in Table-4 of IS:7098 (Part-II)/1985. The joints in Armour strips if any shall be made by brazing or welding and the surface irregularities shall be removed. A joint in any strip shall be at least 300 mm. from the nearest joint in any other armour strips in the completed cable.

5.9 OUTER SHEATH:

5.9.1 The outer sheath shall be applied by extrusion over the armouring. The colour of outer sheath shall be black.

5.9.2 The thickness of the outer sheath shall be as per Clause No.17.3 of IS: (Part-

II)/1985 with latest amendments.

6. TYPE TESTS:

6.1 The material offered, shall be fully type tested as per relevant standard of specification of IS:7098 (Part-II/1985) amended up to date. The bidder must

414

furnish type test reports of similar rating & design of tendered material as detailed at Schedule-IIIA.

The following shall constitute type tests:


i) Annealing test (for copper) ii) Tensile test (for aluminium)

v) Wrapping test (for aluminium) vi) Conductor Resistance test

b) Tests for armouring wires/strips. c) Tests for thickness of insulation and sheath. d) Physical tests for insulation:


iii) Hot test. iv) ) Shrinkage test. v) Water absorption (gravimetric).

e) Physical test for outer sheath:

i) Tensile strength and elongation at break. ii) Ageing in air oven. iii) Shrinkage test. iv) Hot deformation,

f) Partial discharge test. g) Bending test.

h) Dielectric power factor test:

i) As a function of voltage. ii) ) As a function of temperature.

ii) Insulation resistance (volume resistivity test).

j) Heating cycle test.

k) Impulse withstand test.

l) High voltage test.

m) Flammability test.

6.2 However, the purchaser reserves the right to demand repetition of same or all

the type tests in presence of purchaser’s representative.

6.3 The bidder must also clearly indicate various testing facilities available at works for testing the material as per relevant standards. In case of otherwise particulars of the place where such testing is proposed to be conducted during the course of inspection shall be indicated with the offer.

415


7.1 The inspection may be carried out by the purchaser at any stage of . Acceptance of any equipment / material under this specification by the purchaser shall not relieve the supplier of his obligation of furnishing equipment in accordance with the specification and shall not prevent subsequent rejection if the equipment/material is found to be defective. The following Acceptance tests as per Clause No.18.2 of IS:7098(Part-II)/1985 shall be conducted in presence of the purchaser's authorized representative / agency on each lot of offered cables:

i) Tensile Test.

ii) Wrapping Test. iii) Conductor Resistance Test. iv) Test for thickness of insulation & sheath. v) Hot Set Test for insulation.

vi) Tensile strength & elongation at break test for insulation and sheath. vii) rtial Discharge Test (for screened cables only). viii) High voltage test and xii) Insulation resistance (Volume resistivity) Test. xiii) Test for Armour:

a) Verification of Dimension of Strip. b) Tensile Strength & elongation at break. c) Uniformity of Zinc Coating. d) Weight of Zinc Coating. e) Winding Test on Armour. f) Resistivity Test on Armour.

Cold impact test for outer sheath (IS:5831/1984) shall constitute the optional test and shall be conducted on first lot of the offered cables of each size as per Clause No.18.4 of IS:7098(Part-II)/1985.

7.2 ROUTINE TEST:-

The following shall constitute routine tests: d) Conductor resistance test e) Partial discharge test f) High voltage test.

7.3 The bidder shall furnish Packing list mentioning serial Nos. of Drums, in

each drum, gross weight of drum without lagging alongwith inspection offer duly signed by the authorized representative of the firm. The purchaser reserves the rights to insist for witnessing the acceptance / routine tests of the bought out items.

7.4 At least 5% of total numbers of drums subject to minimum of two (2) in the lot put

up for inspection shall be selected at random to ascertain the length of cable by the following method.

“At the works of manufacturer of the cable shall be transferred from one drum to

another for checking any manufacturing defects in the cable, at the same time measuring its length with the help of the graduated pulley and cyclometer. The difference in average

416

length thus obtained from the declared length by the supplier in the packing list shall be applied to all the drums if the cable is found short during checking the sample lot (s).”

7.5 The supplier shall present the latest Calibration Certificate(s) of testing

instruments / equipments to be used for the testing of the material covered in the Purchase Order to the authorized inspecting officer/ inspecting agency of the purchaser. The testing instruments/ meters/ apparatus etc. should be got calibrated by the supplier from time to time from Govt. Laboratory or any independent test laboratory/house having valid accreditation from National Accreditation Board for Testing and Calibrating Laboratories for the testing equipments / original manufacturer having trace ability to NABL/NPL or equivalent.

7.6 The calibration certificate(s) should not in any case be older than one year at the

time of presenting the same to the inspecting officer/ inspecting agency of the purchaser. The testing instruments/ equipments should be duly sealed by the Calibrating Agency and mention thereof shall be indicated in the calibration certificate(s).


i) Sample drums from the material received at stores shall be selected for testing at CTL as per sampling plan given hereunder in presence of firm’s representative. The selected sample drum / drums shall be transported to CTL by concern S.S / ACOS of Nigam.



iii) The tests in the Nigam Testing laboratory (CTL) shall be conducted in the presence

of representative of supplier for which a 7 days notice shall be issued through Fax / Speed Post stating Date & Time to the firm, so that supplier can depute their representative to witness the test . In case the supplier or his representative does not turn up the testing shall be proceeded & completed. The payment shall be released only after receipt of successful test reports for the samples selected at purchaser’s stores for mandatory test checking on the samples to be selected from material received at Nigam’s stores by random sample selection by the authorized committee as per CE(MM) order No.180 dt.11.4.

iv) SAMPLING:


v) TESTS: The following tests shall be carried out as per relevant clause of latest IS on

each selected drum by drawing sample of 10 Mtr. at CTL from random distance during re-winding:

417

a) Rewinding test (Measurement of Length) & Checking of Manufacturing defects. b) Measurement of Resistance of conductor. c) Tensile strength & Elongation at Break Test for Insulation & Sheath d) Test for Thickness of Insulation & Sheath e) Hot Set Test f) Test for Armour:

i) Verification of Dimension of Wire / Strip. ii) Tensile Strength & elongation at break. iii) Uniformity of Zinc Coating. iv) Weight of Zinc Coating. v) Winding Test on Armour. vi) Resistivity Test on Armour.




a) If the measured of conductor resistance of the sample(s) exceeds beyond 2% as per the resistance specified in the contract, the material shall be rejected and the same shall have to be replaced by the supplier.

b) If the measured conductor resistance of the sample(s) exceeds the value

specified in the contract but does not exceed by more than 2% of the resistance value specified in the contract, the material contained in the lot / sub-lot to which the sample belongs shall be accepted with a deduction @ 1.5% of the cost of cable for increase in resistance for every 1% or part thereof.

a) If the sample(s) fails in any other test, the material shall be rejected and shall

have to be replaced by the supplier.

b) If the contractor / supplier fails to lift the material declared rejected or any part thereof from the consignee within a period of 15 days from the date of dispatch of information from the purchaser, the purchaser shall be entitled to effect recovery along with other actions as per Clause No. 1.62 of Section-II (General Condition of Contract).

c) The results of measurement of length test shall be made applicable to all drums

contained in each lot / sub lot by making deduction of less length of cable in a Sample Drum.

7.9 TEST CHARGES :



8 IDENTIFICATION:

418

8.1 The manufacturer shall be identified throughout the length of cable as per Clause No.20.1 of IS:7098(Part-II)/ 1985.

8.2 The cable code employed shall be as per Clause No.20.3 of IS:7098 (Part-II)

/1985.

8.3 EMBOSSING:

The cable shall also be required to be embossed with the word `Name of manufacturer or Trade name, ELECTRIC/ Voltage Grade/ IPDS/ TN- / cable code, size of cable & year of manufacture at every meter length for which no extra charges shall be paid. The cable should be ISI marked & same should be embossed on the outer sheet of every meter length of HT Cable.

9. MARKING:

The progressive length of cable in meter shall be marked on the outer sheath

of every meter length of HT Cable.


10.1 The cable shall be wound on a non returnable wooden drum conforming to IS: 10418/1982 of suitable size. The ends of cables shall be sealed by means of non-hygroscopic material. Only one cable length shall be supplied on a drum. The cable can also be supplied on M-Steel Drums as per relevant ISS as applicable.

10.2 The cable drums shall carry the following information either stenciled or

painted.

i) Manufacturer's name, Brand or trade mark. ii) Type of cable and voltage grade.

iii) Number of cores. iv) Nominal cross-sectional area of the Conductor. v) Cable Code.

vi) ) Length of cable on the drum. vii) Direction of rotation of drum (by means of an

arrow). viii) ross mass. ix) Year of manufacture. x) ISI Certification mark.

xi) ) Purchase order/bid No. and xii) Name of Consignee.

11. STANDARD LENGTH: The cable shall be supplied in standard length of 250

Mtrs in one Drum for size 33 KV, 3CX300 Sq.mm.

11.1 A tolerance of (+/-) 5% shall be allowed on standard length.

419


The bidder shall furnish guaranteed technical particulars in the relevant Schedule VA & VB.

13. DRAWINGS & DOCUMENTATIONS:

The bidder is required to furnish the detailed constructional drawing of cable clearly

showing shape of core, type, size of fillers/ interstices along with Center Filler etc. The calculations of weights of different components of the cable along with weight of armouring and calculation of number of armour strips indicating Lay Ratio & Lay Factor shall also be furnished. In absence of this, the bids are likely to be ignored. The drawing of drums shall also be furnished as per relevant applicable ISS.

420

Schedule-IIIA

1.0 TYPE TEST CRITERIA:- 1.1 The bidder shall furnish valid and authenticated type test certificate from a Govt.

approved / Govt. Recognized / NABL Accrediated laboratory / ILAC i.e. International laboratory Accrediation Corporation (In case of foreign laboratory) / of similar rating and design of tendered material / equipment. Such type test certificate should not be older than five years as on the date of bid opening For this purpose date of conducting type test will be considered.




421

OF Schedule-VA

GUARANTEED TECHNICAL & OTHER PARTICULARS FOR THE SUPPLY 3 CORE 33 KV XLPE CABLES

S.. P A R T I C U L A R S UNIT

No. 3CX

1 Manufacturer's name and works address -

2

Manufacturing process ( Please specify any one of following):

a) CCV Line Process ( Dry Curing)

b) Syoplas Process

3

Standard specification to which the material shall conform. ------------------------------------------------------------------------------------------- I

4

Type of cable and voltage grade. - ---

5 Power frequency withstand voltage KVrms. To be

6

Permissible voltage & frequency variation for To be

satisfactory operation.

i) Voltage %

ii) Frequency %

iii) Combind voltage & frequency %

7

Conductor details :

a) Aluminium grade. - H2/H4 grade, Class-2 conforming to

IS:8130/

b) Nominal cross sectional area (guaranteed). Sq.mm 300

c) Shape of the stranded conductor. - -----------Compact Stranded-------------

d)Number of strands in each conductor(Min) Nos. 3

e)Nominal diameter of each inlet wire before stranding mm To be

422

f) Maximum permissible resistance of Conductor at 20 Deg. C.

Ohms/ Km.

0.100

8

Diameter over laid-up cores

mm

To be furnished by the tenderer.

9 Conductor screening : To be furnished by the tenderer.

a) Type and material. -

b) Continous working temp. Deg.C

c) Max. allowable temp. at termination of Short Circuit

Deg.C

10

Insulation :

a) Material - Cross-Linked Polyethylene conforming to

IS:7098(Pt.2) latest version.

b) Nominal thickness of insulation mm 8.8

c)Minium thickness of insulation. mm 7.82

d) Approx. diameter of core over insulation. mm To be furnished by the tenderer.

11

Insulation screening :


a) Material. -

b) i) Approx. thickness of semi-conducting part. mm

iii) Thickness of metallic part.

mm

S.. P A R T I C U L A R S UNIT 33 KV

No. 3CX300SQ.MM.

c) Approx. diameter of cable over screening.

mm

12

Wheteher Binder Tape provided


13

Inner sheath :

423

a) Material - To be furnished by the tenderer.

b) Process of application -

c) Min. thickness of inner sheath. mm 0.7 mm

d) Diameter of cable over inner sheath mm To be furnished by the tenderer.

14

Type of filler used

a) Material

b) Shape and size mm

c) Central filler (shape & size) mm

15

Armouring :

a) Material and type of armouring - Galvanized Steel Strip

b) Nominal dimensions of Armour mm 4.0 x 0.8 mm

c) Whether galvanised. - Galvanized

d) Lay Ratio of Armouring

i) Minimum

ii) Maximum

e) Total Number of Armour Strips Nos. To be furnished by the tenderer.

f) %age Covering with Armour Strip

g) Diameter of cable over armouring

mm


16 Outer sheath :

a) Material

- PVC Type ST-2 conforming to IS:5831

latest version

b) Nominal thickness of outer sheath.

mm As per Table-5 of IS:7098(Pt.2)/1985 with

latest amendments

c) Colour of sheath. ------------------Black-----------------

17 Approx. over all diameter of cable. mm To be furnished by the tenderer.

18

a) Minimum weight of Aluminium in Kg./Km. corresponding

Kg/Km

2432

to nominal cross sectional area of conductor.(guaranteed)

424

b) Total weight armouring Kg/ Km. Kg/Km

c) Total weight of PVC contents Kg/ Km. Kg/Km

(Inner / Outer Sheath / Filler)

d) Total weight of XLPE including weight of Kg/Km To be furnished by the tenderer.

Conductor Screening and Insulation Screening

(Non- Mettallic) in Kg./Km.(Min.)

e) Total weight of insulation screening Kg./Km. (Mettalic)

f) Total weight of finished cable Kg/Km. Kg/Km To be furnished by the tenderer.

19 i) Standard length of cable. Mtrs 250

ii) Tolerance on standard length.

-------------(+/-) 5% ------------------

20 No. of length(s) of cable on each drum. Mtrs ------------------One-------------------

21

Approx. gross mass of each drum including cable.

Kg



No. 3CX300SQ.MM.

22 i) Drum Size(as per IS:10418/1982) To be furnished by the tenderer.

ii)Details of Drums

To be furnished in the enclosed Schedule-V(B)

iii)Approx. net weight of each empty drum. Kg To be furnished by the tenderer.

23 Max. continous AC current carrying capacity : To be furnished by the tenderer.

a) When laid directly in ground. Amps

b) When laid in covered trenches. Amps

c) When laid vertically in air. Amps

24 Recommended length of laying. cm To be furnished by the tenderer.

25 Short circuit current carrying capacity and KA-Sec To be furnished by the tenderer.

duration of short circuit.

26 Allowable/attainable max. conductor temp. when Deg.C ------------------90--------------------

carrying continous rated current.

27 Allowable/attainable max. conductor temp. at the Deg.C -------------------250------------------

425

termination of short circuit current.

28 Voltage drop per 1000 metres length of cable at To be furnished by the tenderer.

rated current :

a) When laid directly in ground. Volts

b) When laid in covered trenches. Volts

c) When laid vertically in air.

Volts

29 Max. conductor temp.

a) When laid directly in ground. Deg.C ------------------90--------------------

b) When laid in covered trenches. Deg.C ------------------90--------------------

c) When laid vertically in air. Deg.C ------------------90--------------------

30

Impulse strength

KV As per IS - 7098 Part-2 / 1985 with latest

amendment

31 a) DC resistance of each conductor at 20 Deg.C (Max.)

Ohms/ KM

As per IS - 7098 Part-2 / 1985 with latest amendment

b) AC resistance of each conductor at 90 Deg.C.(Max)

Ohms/KM


c) Approx. reactance of each conductor Ohms/KM To be furnished by the tenderer.

d) Approx. capacitance of each conductor Micro-F

KM


e) Insulation resistance (Min.) To be furnished by the tenderer.

i) At 27 deg.cent. Ohm-Cm

ii) At 90 deg.cent.

f) Loss tangent To be furnished by the tenderer.

i) As a function of voltage

ii) As a function of temperature.

g) Dielectric constant. - To be furnished by the tenderer.

32 Charging current at normal operating voltage. Amps/KM To be furnished by the tenderer.

33 Derating factors: To be furnished by the tenderer.

Furnish charts showing derating factors for:

i) Variation in ambient temp. from 30 DEG.C. upto

70 DEG.C. in steps of 5 DEG.C.

426

ii) Variation in ground temp. from 25 DEG.C. upto

60 DEG.C. in steps of 5 DEG.C.

iii) Different specing of cables in horizontal

single row formation for 3 Core Cables under the

following conductions of laying:

a) Cables laid on cable trays in concrete cable


No. 3CX300SQ.MM.

b) Cables laid on cable trays in air.

c) Cables laid in ground.

d) Cables laid in pipes or ducts.

e) Variation in depth of laying for cables laid direct in ground

f) Variation in Thermal resistivity of soil for cables laid in ground

34 Quantity Tolerance -----------------(+/-) 2%----------------

35

Recommended min. bending radius.

mm


36

Embossing

As per specification TN-

37

BIS licence no. & validity


38

ISO:9001 certification

39 Any other particulars To be furnished by the tenderer.

NOTE : SPECIFIC VALUES MAY BE INDICATED IN ABOVE SCHEDULE. USE OF `DO OR AS

PER "IS" IS TO BE AVOIDED.

427

Schedule-VB GUARANTEED TECHNICAL AND OTHER PARTICULARS OF DRUM FOR SUPLY OF 33 KV, 3CX300 SQ. MM XLPE CABLES AGAINST TN-4552

S. P A R T I C U L A R S 33 KV XLPE CABLES

No. 3CX300 SQ. MM

A Drum Size (in mm)

B Flange Diameter(d1) (mm)

C Barrel Diameter(d2) (mm)

D Centre hole Diameter(d3) (mm)

E Overall width (L1) (mm)

F Traverse (L2) (mm)

G Thickness of Flange

H Barrel End (supporting disc

or core segment)

a) Diameter (mm)

b) Thickness (mm)

I Stretchers( Core Carrier Planks)

a) Number (Min)

b) Thickness x width (mm)

J

Barrel Battens thickness

(Core Filler Planks)

K

Barrel Middle Supports

(Middle Core discs)

L

Thickness of External Laggings.(mm) AS PER IS 10418/1982 WITH LATEST AMENDMENTS

DETAILS OF METAL COMPONENTS:

428

M Clamping Studs with Hexagonal Nuts

a) Numbers

b) Diameter (mm)

N

Square or Round Washers

a) Numbers

b) Diameter (mm)

O

M.S. Bushes

a) Numbers

b) Thickness of Sleeve (mm)

c) Dimension of Sleeve (mm)

d) Number of Bolts

e) Diameter of Bolts

P

M.S./ C.I. Centre Plate

a) Numbers

b) Dimensions of Square/

Triangular equal sides (mm)

c) Centre Plate Bolts.

Q

Numbers

i) Diameter of bolts (mm)

ii) Centre Hole Diameter (mm)

429

TECHNICAL SPECIFICATION FOR NFC TYPE ANCHOR (DEAD END) & SUSPENSION ASSEMBLIES FOR LT AERIAL BUNCHED XLPE INSULATED ALUMINIUM CONDUCTOR CABLES WITH BARE MESSENGER WIRE AS WELL AS INSULATED MESSENGER WIRE FOR OVER HEAD LINES SUITABLE FOR WORKING VOLTAGE UPTO AND INCLUDING 1100 VOLTS

1.0 SCOPE

1.1 This specification covers manufacture, testing before dispatch, supply and delivery F.O.R. Destination of anchor (dead end) & suspension assemblies suitable for LT Aerial Bunched XLPE Insulated Aluminum Conductor Cables with bare messenger as well as Insulated Messenger Wire for LT Overhead lines suitable for working voltage up to & including 1100 Volts.

2.0 REFERENCE STANDARDS:

The design, performance and test requirements shall conform to this specification and the following standards. However in case of any conflict, the requirements of this specification shall prevail.

S.No. Standard Details

1 NFC 33-040 Suspension Equipments

2 NFC 33-041 Anchoring Devices

3 NFC 33-003 Corrosion resistance

4 NFC 20-540 Climatic Ageing

5 IS 14255 LV Aerial Bunched Cables

6 IS 8130 Conductors for Insulated cables

7 IS 7098 Part 1 XLPE Insulated Cables for working voltagesupto 3.3 KV

8 IS 398 Part IV aluminum alloy conductors

9 ASTM A 480 Stainless Steel

10 REC 32/1984 REC Specification for Aerial Bunched cable forL T Line

The Devices shall also be compatible with the cables of sizes & dimensions as defined in the Cable Specifications for the cables with which they are intended to be used, and this specification.

430


S.No. Particulars Details

1 Peak ambient temperature in shade 50 deg.C

2 Maximum average ambiant temperature in a 24 hours period in shade

50 deg.C

3 Min. ambient air temperature in shade (-) 5 deg. C

4 Maximum temperature attainable by an object exposed to sun.

60 deg.C

5 Maximum relative humidity. 90%

6 Average number of thunder storm days per annum.

40

7 Average number of rainy days per annum.

100

8 Average annual rain fall 10 to 100 cm

9 Number of months of tropical monsoon conditions.

4 months

10 Maximum wind pressure 100kg/mtr sq

11 Altitude not exceeding 1000 m

4.0 CABLE DATA The standard sizes and characteristics of the phase and street lighting conductors, messenger wires shall be as specified in IS: 14255-1995.

S. No.

Description of Aerial Bunched Cable (Insulated or Bare Neutral Messenger)

1 3Cx25 (Phase) + 1x25 (Insulated or Bare neutral Messenger) + 1x16 mm² (Street Lighting Cable)

2 3Cx35(Phase) + 1x25 (Insulated or Bare neutral Messenger) + 1x16 mm² (Street Lighting Cable)



Table-1

431

5.0 THE ABC ACCESSORIES

The Accessories of LT XLPE Insulated Aerial Bunched Cables (ABC) are specified below:

a) Their design should incorporate specific features to prevent damage to the insulation while meeting the required electrical, mechanical & thermal requirements.

b) The accessories should provide “Double Insulation” so that a single point failure of insulation will not result in the system tripping.

S.No Description Application

a)

Anchoring Assembly (AA)

For fitting onto a pole for anchoring the end of a length of ABC, or for a major change in direction.

The anchoring assesmbly consists of one wedge type anchoring clamp, one aluminium alloy pole bracket, Stainless Steel strap of 1.5 meter and two buckle for fixing the pole brackets with straps.

b)

Suspension Assembly (SA)

For supporting a length of ABC at an intermediate pole in alength, with small angle of deviation.

The suspension assesmbly consists of one wedge typeanchoring clamp, one aluminium alloy pole bracket, StainlessSteel strap of 1.5 meter and two buckle for fixing the pole brackets with straps.

c) Service Clamps To provide the service connections to consulmers.

d) Service Pole Brackets

To provide an anchoring point for service clamps

Table-2

6.1 Anchoring Clamp for Neutral Messenger:

Anchoring assemblies are used to firmly attach the messenger of ABC to a concrete or steel pole and transmit the mechanical tension.

432

at the end of a run at a major change in direction of over 30 degrees.

The clamp should consists of an Aluminium alloy corrosion resistant casted body or climatically resistant polymer material, flexible rope sling (“bail”) of stainless steel and self adjusting plastic wedges which shall anchor/hold the neutral messenger without damaging the insulation, if any.

There shall be no loosable part in the process of clamping arrangement. Slip strength should be not less than 90% of the strength of the messenger. Mechanical strength should be not less than slip strength & no permanent deformation more than 10 mm should occur during slip test.

6.2 Anchoring Assembly

Each Anchoring Assembly shall include:

One number pole bracket. One number wedge type tension clamp as described above

Anchoring assemblies shall be supplied in sets to ensure compatibility of the materials against corrosion or wear of moving parts.

The above hardware/ accessories shall be suitable for use with LT Aerial Bunched XLPE Insulated cable conforming to IS: 14255/1995.

6.3 Pole Bracket for Anchoring Assembly

The pole bracket shall be made out of a single piece Aluminium alloy made of gravity die casting and further heat treated to required strength. Extruded aluminium brackets are not allowed due to sharp corners. The brackets for suitable for attachment to a pole by two stainless Steel straps of length 0.75 meter and width 20mm ±0.2 x 0.7mm ±0.05 and buckle as described later in this specification. The pole bracket should be designed with a closed hook; to ensure that Flexible rope (Bail) cannot slip out at any angle. The inner side of the bracket should be min 100 mm from the surface of the pole.

433

The pole bracket should be tested for the loads not less than slip strength of Clamp with the load applied at an angle of 45° from the normal to the surface of mounting of the bracket :-

Messenger Conductor Size

Range (mm²)

T-Start

(1 Minute) (KN)

T-Final

<30mm & no-break

(KN)

25 - 70 12.0 15.0

Table : 3

6.4 3Flexible Rope( Bail ) of Anchor Assembly

a) The Anchoring assembly shall be supplied with a stainless steel flexible Rope to connect the Tension Clamp to the pole bracket.

b) The flexible Rope forming part of clamp should be of length to maintain at least 150 mm distance between bracket and body of clamp and shall have sufficient mechanical strength to withstand the mechanical test for the complete assembly tests in this specification, as specified in above Table.

c) The rope should have sufficient flexibility to ease the torsional movement of the ABC System.

d) The Rope should be pre-fitted with compression type end fittings which needs to be removable and re-fittable at one side of the clamp and locked at the other end of the anchoring clamp.

e) A wear resistant moveable saddle should be un-loosably fitted on the Rope to prevent abrasion at the point of fitting into the tension bracket. Saddle to be made of plastic for insulation.

f) Rope should have sufficient mechanical strength to with stand the mechanical test for the complete assembly tests in this specification.

434

6.5 Wedge Type Tension Clamp of Anchoring Assembly

a) Wedge type clamps shall be used for clamping the messenger without damaging the insulation in case of insulated messenger or strands in the cable of bare messenger.

b) The clamp shall be capable of clamping an uncut messenger so that it can continue without break to the connecting point or next span.

c) The clamp shall be of aluminum or polymeric body with fully insulating type of mechanical and weather resisting thermoplastic wedges for both bare & insulated messenger. The insulating properties should meet the requirements of voltage test .

d) No bolts or loose parts are allowed as part of the Clamping system.

e) One tool is required for fitting of each sub lot/ lot of 1000 sets or part thereof .

f) The clamp shall be self tightening and capable of holding without slippage the load specified as below:

Messenger Conductor Size Range (mm²) T start (1Minute)

(KN)

T final

(KN) Section Area (mm2) Dia (mm)

25 - 35 8 – 11 8.0 10.0

Table-4

7.1 Testing requirement of Anchoring Assembly (For Insulated or bare messenger)

The following tests are intended to establish design characteristics as per NFC-33-041:-

Sr Test Type Test

Acceptance Test

Routine Test

a Visual √ √

b Dimensional √ √

c Mechanical & Slip strength √ √ √

d Voltage √ √

435

e Corrosion √

f Climatic √

g Mechanical strength of Bracket & SS Strap with Buckle

√ √ √

7.2 Visual

Design aspects of the anchoring assembly needs to be visually verified as per the descriptions of this specification and criteria defined by the manufacturer in the quality plan and as accepted by customer. Following Mandatory marking should be available.

7.3 2 Marking

The marking allowing the identification of the samples shall be legible when examined with normal or corrected vision, without magnification.

a) Manufacturer`s name or logo or trade name

b) Month /year of manufacturing/ TN No.----/IPDS

c) Product Reference

7.4 Dimensional

Overall dimensional to be verified against the GA Drawings. All dimensional requirement mentioned in this specification should be verified. The manufacturer may have his own design, provided the design is conforming to the technical requirements of this specification with minimum dimensions as shown in the specifications.

7.5 Mechanical & Slip Strength Test:

No continuous slippage of slippage of neutral messenger nor clamp break down should occur before the value specified in Table-4

After fitting the messenger in the clamp, load should be increased to 90% of breaking load of Messenger held for 1 minute.

436

7.7 Voltage Test

Voltage test is carried out on anchor clamps to ensure no damage is caused to the insulated messenger and no separate earthing of pole is required in case of bare messenger.

A conductive rod of dia. corresponding to the average dia. that can be accommodated in the clamp is fitted into the clamp, protruding by approx. 50mm at each end of the tightening piece .

A power frequency voltage of 6 kV is applied for 1 minute between the rod and conductive part of the clamp or fixation point in absence of conductive part. No break down or flashover shall occur (tripping of voltage generator)

7.8 Corrosion test

This test is carried out on the anchoring assembly which is subjected to corrosion test as per NFC 33003 or equivalent IS Standard.

7.9 Climatic Ageing test

This test is carried out anchoring assembly which is subjected to corrosion test as per NFC 20540.

8.1 SUSPENSION ASSEMBLY FOR INSULATED OR BARE NEUTRAL MESSENGER: Suspension Assembly is used for supporting an ABC by installation on the messenger at an intermediate point of support such as a pole. It can accommodate small angles of deviation upto 30 deg.

The clamp should be designed to hang L T AB cable with bare or insulated neutral messengers. The neutral messengers should be fixed by an adjustable grip device. A movable link should allow longitudinal and transversal movement of the clamp body.

There should be no loosable part in the process of clamping arrangement. The clamp and the link should be made of Polymer to provide an additional Insulation between the cable and the pole to eliminate need for earthing. The clamps and movable links should be made of weather and UV resistant polymer.

437

Clamps should be fixed to the pole by aluminium bracket. Bracket should be made of corrosion resistant aluminium alloy made out of gravity die casting process and further heat treated to required strength. Extruded aluminum brackets are not allowed due to sharp corners. Brackets should suitable for fixing to pole by means of two S S Strap of 20mm ±0.2 x 0.7mm ±0.05 mm and SS Buckles.

Each Suspension Assembly shall consist of:

One number Suspension Bracket. One number moveable (articulated) connecting link. One number Suspension Clamp.

Suspension Assemblies shall be supplied in sets to ensure compatibility of the materials against corrosion or wear of rotating/moving parts.

Ultimate tensile strength of the clamp should not be less than 90% of messenger strength in direction perpendicular to the direction of the messenger.

The above hardware/ accessories shall be suitable for use with LT Aerial Bunched XLPE Insulated cable conforming to IS: 14255/1995.

8.2 Suspension Clamp of Suspension assembly:

Suspension Clamps are used for locking the messenger of the ABC Bundle without damaging the insulation if any or allowing the messenger to become dismounted from the fitting.

The suspension clamp shall be made fully of insulating type of mechanically strong and weather resistant plastic.

The suspension clamp shall be suitable for messenger wire sizes from 16 to 35 sq mm shall be capable of holding the neutral messenger up to the vertical load value mentioned in table 5 below

Suspension Clamps for bare messengers shall be different from and easily distinguishable from those for insulated messengers One tool is required for fitting of each sub lot/ lot of 1000 sets or part thereof .

There should be no loosable parts in the Suspension clamp.

The suspension clamp shall be unloosably fitted to the suspension assembly.

438

Messenger Conductor Size Range (mm²)

T start (1Minute)

(KN)

T final

(1Minute) (KN) Section Area (mm2) Dia (mm)

25 - 70 6 - 14 10 12.0

Table-5

8.3 Movable (articulated) link of Suspension assembly.

Movable links are used between the suspension bracket and the suspension clamp to allow a degree of movement and flexibility between the two.

Movable links should be made fully of insulating type of mechanically strong and weather resistant plastic. The movable link shall be unloosably fitted to the suspension assembly.

8.3 SuspensionBracketofSuspensionassembly

The Suspension Bracket shall be made from single piece aluminium alloy suitable for attachment to a pole by

a) Two stainless steel straps of length 0.75 meter ans width 20mm ±0.2 x 0.7mm ±0.05 mm and S S buckles.

The Suspension Bracket shall be provided with an upper bulge to prevent the clamp from turning over on the Bracket for more than 45° from the horizontal or to within less than 60 mm from the pole. The Suspension Bracket should be so designed to ensure that the Movable link cannot slip out of it.

9.1 TESTING REQUIREMENTS OF SUSPENSION ASSEMBLY

Following tests are intended to establish design characteristics as per NFC 33-040.

S.No. Test Type Test

Acceptance Test

Routine Test

a Visual √ √

b Dimensional √ √

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c Mechanical & Slip strength √ √ √

d Voltage √ √

e Corrosion √

f Climatic √

h Mechanical strength of Bracket & SS Strap with Buckle

√ √ √

9.2 Visual

Design aspects of the suspension assembly needs to be visually verified as per the descriptions of this specification and criteria defined by the manufacturer in the quality plan and as accepted by customer. Following Mandatory marking should be available.

9.3 Marking:

Following Mandatory marking should be available:-


b) Month/ year of manufacturing/TN No.-----/IPDS


9.4 Dimensional

Overall dimensional to be verified against the GA Drawings. All dimensional requirement mentioned in this specification should be verified. The manufacturer may have his own design, provided the design is conforming to the technical requirements of this specification with minimum dimensions as shown in the specifications.

9.5 MECHANICAL AND VOLTAGE TEST

a) Mechanical Strength Test:

440

No continuous slippage of slippage of neutral messenger nor clamp break down should occur before the value specified in Table-5.

b) Longitudinal Slip test :

There should not be any slip of more than 3 mm in the messenger below 300 N.

c) Voltage Test:

Clamp subjected to a voltage test of 6KV between the conductive parts / fixation and a copper foil which is covered over the maxi allowable cable placed inside the groove of the clamp.

No break down or flashover shall occur (tripping of voltage generator).

9.6 Corrosion Test

This test is carried out on the suspension assembly which is subjected to corrosion test as per NFC 33003 or equivalent IS Standard.

9.7 Climatic Ageing test

This test is carried out suspension assembly which is subjected to corrosion test as per NFC 20540.

10.1 Stainless Steel Strap and Buckles :

The stainless steel strap shall consist of:

a) Stainless steel strap of size 20mm ±0.2 x 0.7mm ±0.05 mm and shall have tensile strength of 7.5KN min., elongation 30% Min, finish 2B, and the stainless steel material shall be of high mechanical strength, corrosion and wear resistant as per ASTM SS 202.

b) Tensile strength of strap is to be min 7.5KN to be tested on a loop with buckle. Number of loops for mounting the bracket on pole to be allocated as per load requirement for dead-end and suspension clamp specified in this specification.

441

c) Min two loops of 0.75 meter each with one buckle to be considered for attaching the brackets to the poles. For dead-end or suspension pole bracket a total of 1.5 meter of SS Strap and two buckle are required.

d) The SS Strap should be engraved with the name of the Manufacturer, month and year of manufacturing and length at a distance of approximate 250 mm for traceability.

e) The S S buckle to suit above strap shall be used to tension & fix it. It should have a slot width of not less than 20.5 mm x 1.5 mm.

f) The Buckle should be made from ASTM SS 304 of thickness not less than 1.2 mm.

g) S S Strap must be supplied in 50 meter roll in plastic dispenser casing with indication of remaining length.

h) Buckles should be supplied in plastic bags containing 100 pcs per bag.

11.1 TEST REQUIREMENTS FOR STAINLESS STEEL STRAP ANDBUCKLES:

Type tests on SS Straps and Buckles shall consist of Chemical Analysis Test Report of Composition. In addition the SS Strap should have been type tested for Tensile Strength and Ultimate Elongation.

S. No. Test Type Test Acceptance

Test Routine Test

1 Visual √ √

2 Dimensional √ √

3 Tensile √ √ √

4 Chemical and Mechanical Properties

√

11.2 Visual

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Design Aspects of the Stainless Steel straps needs to be visually verified as per the descriptions of this specification and criteria defined by the manufacturer in the quality plan and as accepted by customer. Following Mandatory marking should be available.


b) Month and year of manufacturing


11.3 Mechanical&VoltageTests:

a) Mechanical Strength Test:

One loop of SS strap with a length of 0.75 meter and strapped with a buckle should withstand a min load of 7.5 kN.

12. TESTS AND TEST CERTIFICATES:

The Hardwares / Accessories should meet the requirement of all tests as specified in respective NFC standards alongwith other relevant standards and their latest amendments.

The bidder shall furnish valid and authenticated type test certificates from CPRI, Banglore / ERDA, Vadodara / ILAC i.e. International Laboratory Accredited Cooperation (in case of foreign laboratory) only. Such type test certificates should not be older than 05 years as on the date of bid opening. For this purpose date of conducting type test will be considered.

The type test certificate by in house laboratory of tendering firm even if it is a ILAC accredited, shall not be accepted, in case of their own tender.

The bidder should furnish documentary evidence in support of the laboratory whose type test have been furnished, that the said laboratory is a ILAC accredited (in case of foreign laboratory).

The type test certificates shall be furnished either in original or copy duly attested by notary.

The bids of only those bidders shall be considered to be meeting the type test criteria who furnishes complete type test certificate with the bid as per above provision.

Only those bids which accompanied with requisite type test(s) certificate(s) not older than five years as on the date of bid opening, shall be treated as responsive.

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13. TEST CHECKING OF MATERIAL AT STORES:


13.1 SAMPLING

One sample out of each sub lot/ lot of 1000 sets or part thereof from each inspected lot of each type, received in stores shall be selected for test checking of material and shall be got tested. The selection of sample from the material received at stores shall be done as soon as material is received in stores without the presence of the representative of the supplier. However, testing of sample(s) at CTL shall be carried out in the presence of representative of the supplier after identification / confirmation by him that sample so selected belongs to them. In case the supplier disputes that the selected samples does not pertain to them, then fresh sample shall be selected in the presence of the representative of the supplier and test(s) be carried out.

13.2 TESTS


a) Visual examination, verification of dimensions, weight & marking.

The other test as per NFC/IS/REC/ Specification may also be carried out on Suspension & Dead End Clamp subject to availability of testing facility for the same at CTL , Jaipur.

Test of the material shall be got done at the test laboratory of the NIGAM i.e

CTL, Jaipur in the presence of representative of supplier. For witnessing of the testing, clear 7 (seven) days notice shall be given to the supplier by fax/ speed post stating date, time & place where the test is to be conducted. In case the supplier do not attend for witnessing the testing, the testing shall be proceeded and completed and action be taken as per the contract. The Officer Incharge of Central Testing Lab (CTL) Jaipur shall send copies of test reports to the purchaser, consignees and the supplier.


a) Visual examination , verification of dimensions, weight and marking.

As per Specification/ GTP/ Approved drawing.

13.4 TEST CHARGES :

All test charges incurred towards test checking of the material received in our stores shall be borne by the NIGAM except that of personal expenses of the representative of the supplier for witnessing the tests.

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14. PACKING, MARKING AND FORWARDING:

14.1 All hardware fittings shall be packed in suitably sized strong and weather resistant wooden cases/crates. The gross weight of the packing shall not normally exceed 50 Kg.to avoid handling problems.

14.2 Suitable cushioning, protective padding, or spacer shall be provided to

prevent damage to or deformation of the hardwares during transit and handling.

14.3 All identical items shall be dispatched to destination duly assembled

and packed. Bolts, nuts, washers, etc. shall be packed duly installed and assembled with the respective parts and suitable measures shall be taken to prevent their transit loss.

14.4 All packing cases shall be marked legibly and correctly so as to ensure

their safe arrival at their destination and to avoid the possibility of goods being lost or wrongly dispatched on account of faulty or illegible markings. Each wooden case/crate shall have all the markings stenciled on it in indelible ink.

15. GUARANTEED TECHNICAL PARTICULARS:

The tenderer shall furnish guaranteed technical particulars in the schedule –A with drawing .

16. DEMONSTRATION & INSTRUCTION MANUAL:

The successful bidder shall submit the Instruction Manual for erection of Aerial Bunched Cable and Hardware to the sub-division at the time of demonstration of erection of LT Aerial Bunched Cable with Hardware.

The successful bidder shall give free of cost demonstration for erection of Aerial Bunched Cable with Suspension/Dead End Clamp, If asked by Circle Superintending Engineer, in any Sub Division of their Circle, during course of supply. The required Suspension/Dead End Clamp and LT AB Cable for demonstration shall be provided by Nigam.

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SCHEDULE-A

GUARANTEED TECHNICAL AND OTHER PARTICULARS A. Suspension and Dead End Clamp Assembly:

S. No.

Particulars

1 Name of bidder

2 Address of Manufacturer of ABC Accessories

3 Works address

4 a) Is Manufacturer of Accessories an ISO 9001-2000 Company

b) Copy of ISO Certificate enclosed

5 Are GA drawings enclosed for a) Anchor Clamps b) Suspension Clamps

6 Are experience certificate enclosed for a) Anchor Clamps b) Suspension Clamps

A. Anchor Assembly

i Type of Clamp

ii Material of clamp

iii Standard

iv Product Reference and Range of messenger size

v Type of design

vi Installation mode (with / without disassembly)

vii Any bolts or nut used in the design?

viii Type & grade Metallic / Nonmetallic Material

ix Marking

x Dimensions (mm)

xi Weight (Kg)

xii Minimum Breaking Load (KN) (Acceptance test)

xiii Di-Electric test

(Min 6 KV AC for 1 minute) (Acceptance test)

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S. No.

Particulars

xiv Can it accommodate uncut messenger

xv Maximum load holding capacity (Kg.)

xvi Whether the following type test report as per relevant NFC standard furnished a) Voltage with stand test report as per NFC. b) Corrosion Resistance Report as per NFC. c) Climatic Ageing repot as per NFC. d) Mechanical Test

B Bracket

i Is the Material of bracket is die casted and heat treated aluminium alloy (Yes / No)

iii Dimensions (mm)

iv Weight (Kg)

v Minimum Breaking Load (KN) (Acceptance test)

C Suspension Assembly

i Type of Clamp

ii Standard

iii Type Reference and Range of messenger size

iv Installation mode (with / without disassembly)

v Is bracket & movable link included

vi Type & grade Suspension Clamp

vii Is the Material of bracket is die casted, heat treated aluminium alloy (Yes / No)

viii Marking

ix Min Breaking Load (KN) (Acceptance test)

x Di-Electric test

(Min 6 KV AC for 1 minute) (Acceptance test)

D SS Strap

i Material composition

ii Tensile strength per loop fitted with one

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S. No.

Particulars

number buckle

iii Width of Strap

iv Thickness of Strap

v Marking on the strap for manufacturing date, name of manufacturer and length of 250mm (yes/No)

vi Supplied in a plastic dispensable casing for 50 mteres (Yes/No)

SS Buckle

i Material composition

ii Weight of the material

iii Tensile strength (Buckle assembled with one loop of SS Strap_

iv Supplied as a box of 100 nos each

v Is moveable link provided

vi Material of moveable link

vii Material of Suspension Clamp

vii Range of conductor size (mm. Sq.) which suspension clamp can accommodate (mm. Sq.)

viii Max. longitudinal load sustained by clamp

ix Whether the following type test report as per relevant NFC standard furnished a) Voltage with stand test report as per NFC. b) Corrosion Resistance Report as per NFC. c) Climatic Ageing repot as per NFC. d) Mechanical Test

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TECHNICAL SPECIFICATION FOR SUPPLY OF L.T. INSULATION PIERCING CONNECTORS SUITABLE FOR LT XLPE INSULATED AERIAL BUNCHED CABLES WITH BARE MESSENGER WIRE FOR LT OVER HEAD LINES SUITABLE FOR WORKING VOLTAGE UPTO & INCLUDING 1100 VOLTS AGAINST

1. SCOPE :

This specification covers manufacture, testing before dispatch, supply and delivery F.O.R. Destination of L T Insulation Piercing connector suitable for LT XLPE Insulated Aerial Bunched Cables with bare Messenger Wire for LT Overhead lines suitable for working voltage up to & including 1100 Volts as per relevant NFC Standard.

The Insulation Piercing Connectors shall be supplied along with Nuts, Bolts, Washers.


Unless otherwise stipulated in this specification the following standards with latest amendments shall be applicable :

S.No. Particulars

1 NFC - 33-020 Insulation Piercing Connectors

2 NFC - 33-209 LV Aerial Bunched Cable

3 NFC - 33-004 Electrical Ageing Test

4 NFC - 20-540 Environment Testing for outdoor

5 IS 14255 LV Aerial Bunched Cable

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3. CLIMATIC CONDITIONS:

S.No. Particulars Details

1 Peak ambient temperature in shade 50 deg.C

2 Maximum average ambiant temperature in a 24 hours period in shade

50 deg.C

3 Min. ambient air temperature in shade (-) 5 deg. C

4 Maximum temperature attainable by an object exposed to sun.

60 deg.C

5 Maximum relative humidity. 90%

6 Average number of thunder storm days per annum.

40

7 Average number of rainy days per annum.

100

8 Average annual rain fall 10 to 100cm

9 Number of months of tropical monsoon conditions. 4 months

10 Maximum wind pressure 100kg/mtr sq

11 Altitude not exceeding 1000 m

4. GENERAL REQUIREMENTS:

The L.T. Insulating Piercing Connectors are used for making Tee or Tap off connections to LT XLPE Insulated Aerial Bunched Cables suitable up to 1.1 KV, service voltage 0.6 KV. The L.T. Insulation Piercing Connectors are designed to make a connection between the uncut main conductor & a branch cable conductor without removing the insulation and with single tightening. The IPC will first pierce the insulation, then make good electrical contact between the main & the branch conductor while simultaneously insulating & sealing the connection. The teeth of IPC shall be compatible with aluminum phase conductor or aluminum alloy messenger. Exposed metallic parts to be potential free during & after connector mounting.

The performance/ test requirements of insulation piercing connectors shall be as per NFC Standards 33-020.

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The Insulation Piercing Connectors must be equipped with shear heads with minimum & maximum shearing torque as indicated by the manufacturer and within the range specified in NFC 33-020.

The L.T. Insulation Piercing Connectors shall be suitable for LT XLPE Insulated aerial bunched cable of following type & Size:

Type Main Cable Tap Off cable End Cap suitable for Sealing Branch

A 16-50 Sq.mm 2.5-10 Sq.mm 2.5-10 Sq.mm.

B 16-50 Sq.mm 16-50 Sq.mm 16-50 Sq.mm

The Insulation Piercing Connectors must be suitable for application by one worker working alone with a 17mm/ 13mm wrench. Suitable wrenches for installing the connectors shall be included in the scope of supply at the rate of 1 Set for each 1000 Pieces of Connectors ordered (Fraction of 1000 Pieces to be rounded down) The Insulation Piercing Connectors shall be water proof & the water tightness and shall be ensured by appropriate elastomer material & not by grease, gel or paste alone. The Connector shall be provided with removable end cap for sealing cut end of the branch cable enabling tapping on both sides of the connector being in its vertical position with bolt head upward. The end cap shall be rigid of slide type enabling easy positioning and un-loosable

after the tap cable is positioned. The end cap shall be equipped with a water tightness seal. Rubber seal around piercing teeth shall be compatible with grease used. Rubber seal shall be designed in a manner to provide proper sealing around the piercing & to avoid the damage to conductor insulation beyond piercing point. Rubber parts shall comprised of material that exhibit resistance to aging caused by heating or other weather conditions.

All the insulating material used shall be UV resistant. Metallic parts shall be hot dip galvanized or of Stainless steel.

The Insulation Piercing Connectors shall have good finish and shall be free from all flaws, sharp edge and suitably rounded off.

The Insulation Piercing Connectors and its components shall meet the following tests in accordance with the requirements & test methods of NFC 33 – 020:

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a) Mechanical Tests

b) Voltage & water tightness test

c) Electrical Ageing Test

d) Corrosion Resistance Test

e) Climatic Ageing Test

The above hardware/ accessories shall be suitable for use with LT XLPE Insulated PVC sheathed Aerial Bunched Cable conforming to IS:14255/1995 of following sizes:

S.No. Designation of finished cable

1 1CX25+25 mm².

2 3CX16+25 mm².

3 3CX25+25 mm²

4 3CX50+35 mm².

5 3CX35+25 mm²

Note:- The first part of the designation refers to the number and size of the phase conductor and the last to the size of messenger wire. The sizes shown are the nominal cross sectional area of the conductors.

5.0 TYPE TESTS & TESTS CERTIFICATES:

The bidder shall furnish valid and authenticated type test certificates from CPRI, Banglore / ERDA, Vadodara / ILAC i.e. International Laboratory Accredited Cooperation (in case of foreign laboratory) only. Such type test certificates should not be older than 5 years as on the date of bid opening. For this purpose date of conducting type test will be considered.

The type test certificate by in house laboratory of tendering firm even if it is a ILAC accredited, shall not be accepted, in case of their own tender.

452

The bidder should furnish documentary evidence in support of the laboratory whose type test have been furnished, that the said laboratory is a ILAC accredited (in case of foreign laboratory).


The bids of only those bidders shall be considered to be meeting the type test criteria who furnishes complete type test certificate with the bid as per above provision.

Only those bids which accompanied with requisite type test(s) certificate(s) not older than five years as on the date of bid opening, shall be treated as responsive.

The Insulation Piercing Connectors should meet the requirement of all tests as specified in respective NFC standard NFC-33-020 along with other relevant standards and their latest amendments. For ready reference, the applicable tests are reproduced below :

Type Tests:

Insulation Piercing Connectors

S. No. Clause No. of NFC Description of Test

1 2.3.1 Electrical continuity

2 2.3.1 Shearhead

3 2.3.1 Mechanical Behavior

4 2.3.2 Mechanical strength of main core

5 2.3.2 Mechanical strength of Tap core

6 2.4 Voltage and water tightness

8 2.6 Climatic Ageing

9 2.7 Corrosion Test

10 2.8 Electrical Ageing

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The bidder must also clearly indicate various testing facilities available at their works for testing the material as per relevant standard. In case of otherwise particulars of the place where such testing is proposed to be conducted during the course of inspection shall be indicated.

6.0 INSPECTION:

The inspection may be carried out by the purchaser at any stage of manufacture. The successful bidder shall grant free access to the purchasers representative at reasonable time when the work is in progress. Inspection and acceptance of any equipment / material under this specification by the purchaser shall not relieve the supplier of his obligation of furnishing equipment in accordance with the specification and shall not prevent subsequent rejection if the equipment / material is found to be defective.

The acceptance tests shall also be conducted on each offered lot by the manufacturer before dispatch in the presence of purchaser's authorized representative / inspecting officer/ agency as per Clause No.1.27 " Inspection and testing" of "General Condition of Contract" Section-II. The acceptance tests shall be carried out as per relevant NFC standards and GTP furnished by the bidder, whichever is more stringent..

7.0 Acceptance Tests :

The Acceptance Tests for Insulation Piercing Connectors shall consist of the following:

For Insulation piercing Connectors. (NFC 33-020)

S. No. Clause No. of NFC Description of Test

1 3 Marking as per clause 3

2 2.3.1 Electrical continuity

3 2.3.1 Shearhead

4 2.3.1 Mechanical strength

5 2.4 Voltage and water tightness

454

The supplier shall present the latest calibration certificates of testing instruments / equipments to be used for the testing of the material covered in the purchaser order to the authorized inspection officer/inspecting agency of the purchaser. The testing instruments/meters/ apparatus etc. should be got calibrated by the supplier from time to time from NABL accredited laboratory or NPL for Indian Bidders or Nationally accredited test laboratory for foreign bidders. The calibration certificate should not be in any case be older than 1 year at the time of presenting the same to the inspecting officer/ inspecting agency of the purchaser. The testing instruments / equipments should be duly sealed by the calibrating agency and mention their of shall be indicated in the calibration certificates.

8. TEST CHECKING OF MATERIAL AT STORES


8.1. SAMPLING

One sample out of each sub-lot / lot of 5000 Nos. or part thereof for Type-A

connectors and one sample out of each sub-lot / lot of 1000 Nos. or part thereof for Type-B connectors from each inspected lot received in stores shall be selected for test checking of material and shall be got tested. The selection of sample from the material received at stores shall be done as soon as material is received in stores without the presence of the representative of the supplier. However, testing of sample(s) at CTL shall be carried out in the presence of representative of the supplier after identification / confirmation by him that sample so selected belongs to them. In case the supplier disputes that the selected samples does not pertain to them, then fresh sample shall be selected in the presence of the representative of the supplier and test(s) be carried out.

8.2 TESTS


i) Visual Examination, verification of dimensions, marking.

ii) The other acceptance tests as per NFC Standard / specification may also

be carried out subject to availability of testing facility for the same at CTL, Jaipur.

8.2.1 Test of the material shall be got done at the test laboratory of the

NIGAM i.e CTL, Jaipur in the presence of representative of supplier. For witnessing of the testing, clear 7 (seven) days notice shall be given to the supplier by fax/ speed post stating date, time & place where the test is to be conducted. In case the supplier do not attend for witnessing the testing, the testing shall be proceeded and completed and action be taken as per the contract.

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8.2.2 The witnessing officers of the NIGAM or as designated by the purchaser shall send copies of test reports to the purchaser, consignees and the supplier.


i) Visual Examination, verification of dimensions, marking.

ii) The other acceptance tests as per NFC Standard / specification mayalso be

carried out subject to availability of testing facility for the same at CTL, Jaipur.

As per NFC-33-020/1998 for the above test (with latest amendment)

/Specification.

10. TEST CHARGES :


11. EMBOSSING & IDENTIFICATION:

It should be provided in each piece as per Clause No.3 of the relevant NFC standards.

12. PACKING, MARKING & FORWARDING:

All Insulation Piercing connectors shall be packed in Cardboard Cartons. The gross weight of the packing shall not normally exceed 50 Kgs. to avoid handling problems.

Suitable cushioning, protective padding or spacer shall be provided to prevent damage to or deformation of the hardware during transit and handling.

All identical items shall be dispatched to destination duly assembled and packed. Bolts, Nuts, Washers etc. shall be packed duly installed and assembled

with the respective parts and suitable measures shall be taken to prevent their transit loss.

All packing cases shall be marked legibly and correctly so as to ensure their safe arrival at their destination and to avoid the possibility of goods being lost or wrongly

456

dispatched on account of faulty or illegible marking. Each case / crate shall have all the markings stenciled on it in indelible ink.


The bidder shall furnish guaranteed technical particulars in the schedule-B with drawing.

.14. DEMONSTRATION & INSTRUCTION MANUAL:

The successful bidder shall submit the Instruction Manual for erection of Aerial Bunched Cable and Hardware to the sub-division at the time of demonstration of erection of LT Aerial Bunched Cable with Hardware.

The successful bidders shall give free of cost demonstration for erection of Aerial Bunched Cable with Insulation Piercing Connector, if asked by Circle Superintending Engineer, in any Sub Division of their Circle, during course of supply. The required I.P. Connector and LT AB Cable for demonstration shall be provided by Nigam.

457

Schedule-B

B. Insulation Piercing Connectors Type-A and Type-B:

Sl. No. Particulars Type-A Type-B

1. Name of Manufaturer & Address

2. Works’s Address

3. Is Manufacturer of Accessories an ISO 9001 – 2000 Company.

Copy of Certificate enclosed

Are GA drawings enclosed?

Are experience certificates enclosed?

4.0 Insulation Piercing Connectors (provide info separately for each size offered)

Type Number & Size Range

4.1 Is any metallic part carrying potential in operation exposed during installation ?

Metal used for teeth.

4.2 Are end caps for branch cable ?

Slide on Type

Rigid

4.3 Are torque limiting shear heads provided on tightening bolts?

4.4 Range of sizes accommodated for Branch & Main (fill 4.5.1 to 4.7.5 for each size of connector)

4.5.1 Rated tightening torque (Nm)

4.5.2 Min Shear head breaking torque (Nm)

Max Shear head breaking torque (Nm)

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4.6.2 Max. Tensile load for no breakdown of main conductor (for each cross- section). Kg.

4.6.3 Max. tensile on Branch conductor for no slippage / break Kg.

4.7 Voltage withstand under water immersion

4.8 Marking on IPC As per Clause no.3 of NFC

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TECHNICAL SPECIFICATION FOR ACSR PANTHER CONDUCTOR ----------------------------------------------------------------------------------------------------------------

1. SCOPE 1.1 This section provides for manufacture, testing before dispatch, supply and delivery

F.O.R Destination of Aluminium Conductor, Galvanized Steel reinforced (ACSR) Panther Conductor for satisfactory operation in various lines and sub-stations. The conductor should conform to latest IS.

1.2 Aluminium Conductor with galvanized Steel re-inforcement shall be conforming to IS:

398(Pt.2)/1996 with latest amendments if any, supplied on non returnable strong wooden drums generally conforming to IS: 1778/1981 (Latest).

The bidders should be a manufacturer of offered Conductor. The Offers from

sole selling agents / authorized dealer shall not be entertained. The firms (manufacturers) must posses valid ISI License for the offered Conductor. 2. CLIMATIC CONDITIONS:

1. Peak ambient temperature in shade. 50 deg.C

2. Maximum average ambient temperature in a 24 hours period in shade

40 deg.C

3. Min. ambient air temperature in shade (-) 5 deg.C 4. Maximum temperature attainable by an object

exposed to sun. 60 deg.C

5. Maximum relative humidity 100% 6. Average number of thunder storm days per annum 40 7. Average number of rainy days per annum. 100 8. Average annual rainfall 10 to 100 cm9. Number of months of tropical Monsoon conditions. 4 months 10. Maximum wind pressure. 100 kg/ sq. mm.11. Altitude not exceeding 1000 M

3. GENERAL TECHNICAL REQUIREMENT OF ACSR PANTHER CONDUCTOR:

The technical particulars shall be furnished strictly in the proforma attached at Schedule-V-A of this specification. The specific values must be indicated against each column and no 'dash'. 'dot', 'blank' or as per IS word should be indicated in this schedule. The technical suitability shall be adjudged from the values furnished in the clause 3.2 “PRINCIPAL PARAMETERS”.

The ACSR conductor shall comply in all respect with IS: 398(Part.2)/1996 with latest

amendment,

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3.1 MATERIAL

The material offered shall be of the best quality and workmanship. The conductor shall be constructed from hard drawn aluminum and galvanized steel wires which have the mechanical and electrical properties specified in Tables 1 & 2 of IS:398(Part.2)/1996 with latest amendment, if any, The Zinc coating on the galvanized steel wires may be applied in accordance with IS:4826/1979 with latest amendment if any. The EC Grade Aluminium rods for use in the manufacture of Aluminium Wires shall conform to IS:5484/1978 amended up to date. The zinc used for galvanizing shall be Electro type High Grade Zinc not less than 99.95 percent purity. It shall conform to and satisfy all the requirements of IS:209/1992 amended up to date. Galvanized Steel Wire should comply mechanical properties as per Table 2 of IS:398 (Part.2)/1996 amended upto date. The chemical composition is as per Annexure-C of IS:398 (Part.2)/1996 amended upto date.


The details of ACSR conductor are tabulated below:-

PARTICULAR ACSR PANTHER a) Stranding and

wire diameter (mm) 30/3.0 Al. 7/3.0 St.

b) Number of strands Central Steel wire Aluminium

7 30

c) Sectional area of aluminium(Sq. mm) 212.10

d) Total Sectional area (Sq. mm) 261.50

e) Overall diameter (mm) (Approx.) 21.00

f) Weight (Kg/Km) (Approx.) 974.00

g) Calculated max. DC resistance at 20 Deg. C (Ohm./ Km.)

0.1390

h) Approx. calculated breaking load (KN) 89.67

i) Modulus of elasticity (GN/Sq. meter) 80 j) Coefficient of liner Expansion per deg C. 17.8x10-6

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3.3 The details of aluminium strands are as follows:

PARTICULAR ACSR Panther

a) Min. Breaking load of strand before stranding (KN) 1.17

b) Min. Breaking load of strand after stranding (KN) 1.11

c) Max. D.C. Resistance of strand at 20 Deg. C (ohm/Km.)

4.079

d) Diameter mm Nominal Minimum Maximum

3.00 2.97 3.03

e) Mass (Kg/Km.) 19.11

3.4 The details of steel strands are as follows:

PARATICULAR ACSR Panther

i) Min. Breaking load of strand before stranding (KN)

9.29

ii) Min. Breaking load of strand after stranding (KN) 8.83

iii) Diameter mm a) Nominal b) Max./Min

3.00

3.06/2.94

iv) Zinc coating testing 3 dips of 1 min. each

v) Min. weight of zinc coating GM/ Sq. Mtr. 228.00

vi) Mass of strand at normal diameter of strand(Kg./Km.) 55.13

3.5 Tolerance on normal sizes:

The tolerance in diameter of aluminium wires and steel wire used in the manufacture of ACSR shall be allowed as per IS: 398/ (Part-2) /1996 amended upto date.

3.6 Stranding:

3.6.1 The wires used in the construction of a galvanized steel reinforced aluminium

conductor shall before stranding, satisfy all the relevant requirements of this specification and relevant IS.

462

3.6.2 The lay ratio of the different layers shall be within the limits given:

S. No. Particulars ACSR

PANTHER1 Number of wires :

a) Aluminium b) Steel

30 7

2 Ratio of aluminium Wire dia-meter to Steel wire dia-meter 1

3 Lay ratio for aluminium Wires (Outer most layer): a) Minimum b) Maximum

10 14

4. Lay ratio for steel core (6 wire layer) a)Minimum a) Maximum

13 28

NOTE: For the purpose of calculation, the mean lay ratio shall be taken as the arithmetic mean of the relevant minimum and maximum value given in this table.

4. TESTS (FOR ACSR CONDUCTOR):

TESTS BEFORE DESPATCH: The ACSR Conductor shall be subjected at manufacturer’s works before dispatch, to the tests mentioned here-under as per IS: 398 (Part-2)/1996 with latest amended.

4.1 ROUTINE TESTS:

The following tests shall be conducted before and after stranding on each drum of the

conductor by the manufacturer at his works as per relevant standard IS: 398 (Part-2)/ 1996 (latest amended)

a) Visual & dimensional check on drum as per specification.

b) Visual check for joints, scratches etc. and length of conductor by re-winding of

conductor on empty drum as per Specification/ IS.

c) Measurement of dia-meter of individual Aluminium and steel wires.

(Clause-13.2)

d) Measurement of Lay Ratio. (Clause-13.8)

e) Breaking load of individual wires (Clause-13.3.1)

f) Ductility Test (Clause-13.4)

g) Wrapping Test (Clause-13.5)

h) Resistance Test (Clause-13.6)

i) Galvanizing Test (Clause-13.7)

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j) Any other test as per relevant IS 4.2 ACCEPTANCE TESTS:-

The following tests shall be conducted on samples taken at random from a lot as per relevant standard IS: 398 (Part-2)/1996 (Latest amended) in presence of purchaser’s representative:-

a) Visual & dimensional check on drum as per specification.

b) Visual check for joints, scratches etc. and length of conductor by re-winding of

conductor on empty drum as per Specification / IS.

c) Measurement of dia-meter of individual

Aluminium and steel wires. (Clause-13.2)

d) Measurement of Lay Ratio. (Clause-13.8)

e) Breaking load of individual wires (Clause-13.3.1)

f) Ductility Test (Clause-13.4)

g) Wrapping Test (Clause-13.5)

h) Resistance Test (Clause-13.6)

i) Galvanizing Test (Clause-13.7) 5.1. TYPE TESTS

The bidders shall furnish the type test report for the tendered item along with bid as

detailed at Schedule-III A) as per relevant IS:398 Pt.2)/1996 with latest amendment along with bid only for those tests which are not covered under acceptance test.

The following shall constitutes type test which are to be conducted on the samples

taken from Three Drums of the conductor as per relevant IS:398 (Pt.2)/1996 with latest amendment:

a) Stress – Strain Test (Clause No.13.11 of ISS). b) Surface Condition Test (clause No.13.9 of ISS). c) Ultimate Breaking Load Test (Clause No.13.10 of ISS).

6.1 SAMPLING PLAN :

6.2 Samples for Acceptance Tests: Samples shall be taken as per relevant IS i.e. IS-398

(Part-2)/1996 with latest version. 6.3 Apart from the sample selected for carrying out Acceptance Tests at the works of the

firm during inspection, one more sample from each length be also selected out of one drum under re-winding for carrying out various Acceptance Tests as per

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relevant IS. If any of the sample so selected from each length failed in any acceptance test the entire lot under inspection is not acceptable.

6.4 TOLERANCE ON TEST RESULTS:

Tolerance on test results shall be allowed as per relevant IS/Spec. whichever is more

stringent. 7.1 INSPECTION

7.2 (a) The conductor shall be manufactured in accordance with latest edition of

IS: 398(Part.2)/1996 with all subsequent amendments issued from time to time for ACSR Conductor. All the tests as laid down in the above mentioned specification on individual aluminium wire and steel wire shall be carried out. The testing shall also include the tests on manufactured finished conductor. Moreover the supplier shall also furnish test certificate(s) of raw materials to the inspecting officer at the time of inspection. The inspection & testing shall be governed by Clause No.1.27 of Section-II (General Condition of Contract).

(b) The supplier / manufacturer must offer conductor for inspection through a

letter of offer mentioning size and quantity of the conductor along with Packing List duly signed indicating drum Serial No. individual lengths total length, net weight & gross weight in DUPLICATE. This letter of offer shall be addressed to this office. The packing list shall also be furnished to the Inspecting Officer prior to carrying out the inspection at the works.

(c) The Manufacturer shall provide all adequate facilities at his works for

inspection of at least one number conductor drum or 5% conductor drums offered for inspection whichever is higher selected at random by the authorized representative of the purchaser for checking / verification of conductor length/ manufacturing defects by transferring the conductor from one drum to the another empty drum and at the same time measuring the length and lay ratio of each conductor length so transferred by means of the standard calibrated and sealed meter.

(d) If the firm is not having the necessary facilities for carrying out the

required tests as per relevant IS / Purchase Order, the supplier will arrange such testing facilities in some other Government laboratory and shall bear the cost so incurred. But in such cases firm shall inform to the purchaser in advance before commencement of supplies.

(e) The supplier shall provide adequate facilities for weighment of all the drums offered for inspection.

(f) The purchaser has every right for rewinding of conductor drums at stores / site in part or full after receipt of material. If at any time, shortage in lengths than the declared /marked length(s) is observed in any of the drum of the particular lot, the maximum length of shortage so observed in rewound drum shall be deducted from all the drums inspected / dispatch lot. If any inspected lot is consigned to more than one consignee the maximum shortage so observed during rewinding, in respect of any consignee will be deducted from the complete inspected / dispatched lot. However, the

465

purchaser shall intimate in advance to the supplier programme of rewinding to depute their representative to witness rewinding, if supplier desires so. If the supplier does not depute their authorized representative, the rewinding shall be done by store organization in presence of representative of purchaser nominated by the circle Superintending Engineer, Discoms. At the time of receipt of material in store/rewinding in store, if any defect /shortage is found the purchaser shall have every right to deduct the cost of defective / short material or reject the entire lot.

7.3 In case of testing after re-offering as per Clause No.15 of IS:398 (Part.2)/1996, the

lot under reference will be subject to 100% checking, if required by the purchaser. 7.3 The supplier shall present the latest Calibration Certificate(s) of testing instruments /

equipments to be used for the testing of the material covered in the Purchase Order to the authorized inspecting officer / inspecting agency of the purchaser. The testing instruments / meters/ apparatus etc. should be got calibrated by the supplier from time to time from Govt. Lab or Independent test laboratory / house having valid accreditation from National Accreditation Board for Testing and Calibrating Laboratories for the testing equipments or original manufacturer having traceability to NABL / NPL or equivalent accredited lab.


7.4 The manufacturer will provide certificates as per the Clause No.7 of IS: 398((Part.2)/ 1996 “Freedom from defects" and clause No.9 “Joint in Wires" of IS:398 (Part 2) /1996 for ACSR Conductors.

8.1 STANDARD LENGTH & VARIATION IN LENGTHS:

8.2 The ACSR Conductor shall be supplied in the standard length. The standard length of

ACSR Conductor shall not less than the value specified below with a tolerance of (-) 5%. More than the standard length shall be acceptable.

a) ACSR Panther - 1400 Mtrs.

8.3 Short length(s), if any shall not measure less than 80% of standard length as specified

above in any case. The total quantity of such short length(s) shall not exceed 5% of the quantity of the lot offered for inspection.

8.4 The maximum permissible length per drum shall be as under subject to condition

that the manufacturer while packing the conductor in drum shall ensure that after winding complete quantity of conductor in drum a uniform space of not less than 100 mm. remains between outer layer of conductor and inner surface of the external protective lagging of the drum. This is essential to ensure that the conductor does not get closer to the lagging and to avoid damaged during transportation/ reeling / unreeling or rolling on the undulated ground / fields:

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a) ACSR Panther - 1.47 Km. 10.1 PACKING FORWARDING AND MARKING:

10.2 The packing shall have to be done as per standard practice worthy of road transport.

The conductor shall be wound in strong wooden drums so as to withstand all stresses due to transportation, handling and stringing operation so that there is no damage caused to the conductor during the process of these operations. The wooden drums shall be non-returnable and shall generally conform IS:1778/1981 with latest amendments, however, the main parameters of the drum shall be as under:

S.NO. PARTICULARS DIMENSION FOR ACSR PANTHER

CONDUCTOR 1. Flange Dia 1300 mm (+/- 5%) 2. Flange Thickness 2x33 mm (+/- 5%) 3. Barrel Dia 600 mm (+/- 5 %) 4. Traverse 750 mm (+/- 5%) 5. Number of Bolts 4 Nos. 6. Dia of Bolts 12 mm 7. Bore Dia 80 mm

However, use of seasoned wood shall not be insisted, provided wood used should be of good quality to withstand transportation hazards. The drums shall be having inside flanges painted with Aluminium Paint and with Ordinary White Enamel paint from outside. The conductor on each drum shall be securely fastened at each end. The outer end of the conductor shall be fastened inside the drum against one of the sides of the flanges while it is under tension and shall be such that no looseness is transmitted to the internal layers. The conductor shall be snugly, tightly and uniformly spooled on the drums. The wrapping of conductor on the drums shall be laid snugly against side of the preceding wrap and the first and last wrap in each layer shall fit snugly against the sides of the flanges. Drums shall be lagged with sufficient strong wooden laggings to support the full drum without crushing. The wooden drums after providing lagging shall be fastened by two steel wires of min. 3 mm. Dia over the lagging on the two sides of adequate size to keep the lagging intact and to prevent the drum from crushing/ damage.

Although the various dimension of the drums such as flanges, stretches, traverse

and barrel diameter shall depend on the quantity of conductor as offered and agreed upon, on one drum. The manufacturer while packing the conductor in drum shall ensure that after winding complete quantity of conductor in drum a uniform space of not less than 100 mm. remains between outer layer of conductor and inner surface of the external protective legging of the drum. This is essential to ensure that the conductor does not get closer to the legging and to avoid damaged during transportation/ reeling / unreeling or rolling on the undulated ground / fields.

10.3 Water proof material shall be wrapped round the barrel and inner surface of flange

before winding the conductor and also wrapped round over the conductor completely wounded and under the laggings.

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10.4 The drums shall be marked clearly in block letters with water proof mark having the marking attached to them so that there is no possibility of goods being lost or wrongly dispatched due to faulty marking. The marking shall constitute the following:-

a) Name & full address of the consignee. b) Destination station. c) Serial number of drum. d) Size of Conductor with its code name. e) Total length of Conductor in drum, with individual length (s). f) Number of length(s) in each drum. g) Gross mass of drum including the tare mass of drum. h) Tare mass of the empty drum with lagging. i) Net mass of conductor. j) BIS standard mark. k) Name of the supplier. l) IPDS/TN number. m) Date of expiry of warranty / guarantee period.

Besides above, an arrow shall be put on the drum so as to indicate the direction in

which the drum can be unwound. The manufacturer shall also provide his own lead seal with distinguishing mark at the outer end of the conductor on each drum before dispatch of the material.


i) Sample drums from the material received at stores shall be selected for testing at CTL as per sampling plan given hereunder in presence of firm’s representative.


provided by Inspecting Officer / Inspecting Agency during pre-dispatch inspection at firm’s works and these sealing details shall be invariably mentioned in the selection Memo by the nominated officers of Nigam.

iii) The tests in the Nigam Testing laboratory (CTL) shall be conducted in the

presence of representative of supplier for which a 7 days notice shall be issued through Fax / Speed Post stating Date & Time to the firm, so that supplier can depute their representative to witness the test . In case the supplier or his representative does not turn up the testing shall be proceeded & completed. The payment shall be released only after receipt of successful CTL test reports for the samples selected at purchaser’s stores for mandatory test checking the samples to be selected from material received at Nigam’s stores by officers to be nominated by Circle SE’s / SE (I&S) for testing at CTL.

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12 SAMPLING

Selection of samples from the material received at stores shall be done as soon as material received in stores in the presence of representative of supplier.

One number Drum out of each lot / sub-lot of 20 Nos. Drums or part thereof for

the material received in Stores of Nigam. The selected sample drum / drums shall be transported to CTL by concerned ACOS / SS.

In case of selection of sample for type test the length of the sample shall be of 15

Mtrs. The selected and sealed sample for type test shall be identified by providing polycarbonate seals on both ends of conductor and after forming the coil of conductor two stickers seals provided around the coil.

12.1 TESTS

12.1.1. The following tests shall be carried out as per relevant Clause of latest IS-398

(Part2)/1996 on each selected drum by drawing sample of 5 Mtrs. at CTL from random distance from any length of the selected drum of ACSR Conductor during rewinding:

a) Rewinding test (Measurement of Length and weight) & Checking of

Manufacturing defects. b) Measurement of lay ratio during rewinding of Conductor Drum. c) Dia. of Aluminium Strands and Steel Wires. d) Breaking load test. e) Resistance Test. f) Galvanization of steel wire (Uniformity) and Mass of Zinc Coating. g) Verification of Water Proof marking on Drum as per Specification.

12.1.2 The following tests shall be carried out as per relevant Clause of latest IS /

Specification on each selected drum by drawing sample of 5 Mtrs. at CTL from random distance from any length of the selected drum of AAA Conductor during rewinding:

i) Rewinding test (Measurement of Length and weight) & Checking

of Manufacturing defects. ii) Measurement of lay ratio during rewinding of Conductor Drum iii) Breaking Load test iv) Elongation Test v) Resistance test vi) Measurement of dia-meter of individual Aluminium Alloy Wire. vii) Verification of Water Proof marking on Drum as per Specification.

NOTE: (a) In addition to above tests remaining acceptance tests as per

relevant IS shall also be conducted at CTL provided the testing facility is available at CTL for these tests time to time. Only those tests shall be conducted for which testing facilities are available in NIGAM’s Lab.

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(b) The Officer In charge of central Testing Lab (CTL) of Nigam shall send copies of test reports to the Purchasing Officer / Sr. AO (CPC), consignee and the supplier.

(c) The payment of every lot shall be released after receipt of

successful test report from Nigam’s Lab (CTL) on the samples selected from the material received in Nigam stores.

12.2 CRITERIA FOR ACCEPTANCE:

(a) Rewinding Test (Measurement of Length and weight):

The results of measurement of length test shall be made applicable to all drums

contained in each lot/sub-lot by making deduction of less length of conductor in a sample drum. Incase short length is observed more than 1% of the length contained in Lot/Sub-lot then the lot /sub-lot shall liable to be rejected.

The net calculated weight of various type of conductor corresponding to minimum

prescribed diameter in IS of Aluminium Strand, Steel Strand (ACSR Conductor) and Aluminium Alloy Strand (AAA Conductor) shall be as under:

(b) ACSR PANTHER 947.07 Kg./Km.

If weight of conductor corresponding to minimum prescribed diameter as per IS

found less upto 2% in respect to measured length the lot shall be acceptable otherwise the entire lot for which sample drum represents shall be rejected and to be replaced by the supplier.

(c) If the sample(s) fail in any test other than length measurement, the entire material in the Lot shall be rejected and shall have to be replaced by the supplier.

d) If the contractor / supplier fails to lift the material declared rejected or any part thereof from the consignee within a period of 15 days from the date of dispatch instruction from the purchaser, the purchaser shall be entitled to effect recovery along with other actions as per Clause No. 1.62 of Section-II (General Condition of Contract).

13.0 TEST CHARGES:



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SCHEDULE-III A

TYPE TEST CRITERIA :

a) The bidder shall furnish valid and authenticated type test certificate from a Govt. approved / a Govt. recognized / NABL Accredited laboratory / ILAC i.e. International laboratory Accreditation Corporation (In case of foreign laboratory) of similar rating and design (ACSR PANTHER CONDUCTOR) of tendered material / equipment. Such type test certificate should not be older than Five years as on the date of bid opening For this purpose date of conducting type test will be considered. The bidders shall furnish the type test report along with bid.

The type test certificate by in house laboratory of biding firms even if it is a Govt. approved / Govt. Recognized / NABL Accredited laboratory / ILAC accredited, shall not be accepted, in case of their own bid. This will not apply if biding firm is Govt. Company / public sector undertaking.

b) The bidder should furnish documentary evidence in support of laboratory whose type test have been furnished, that the said laboratory is a Government / Govt. approved / Govt. Recognized / NABL Accredited laboratory / ILAC accredited (In case of foreign laboratory).

c) The type test certificate shall be furnished either in original or copy duly attested by Notary.

d) The bids of only those bidders shall be considered to be meeting the type test criteria who furnishes complete type test certificate with the bid as per above provisions.

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SCHEDULE – V A

GUARANTEED TECHNICAL PARTICULARS OF ACSR CONDUCTOR

---------------------------------------------------------------------------------------------------------------- S.NO. PARTICULARS ACSR CONDUCTOR

Panther ---------------------------------------------------------------------------------------------------------------

1. Manufacturer's name

Office address Work's address

Telephonic address Telephone Fax Telex Name of Contact Person

2. Code Name

3. Standard according to which the

conductor will be manufactured and tested.

4. Whether conductor offered bears

BIS standard mark. If yes, furnish copy of registration certificate of Bureau of Indian Standards.

5. Aluminium wires used in the

construction of aluminium conductors galvanised reinforced (ACSR) as per tables of IS;398(Part.2)/1996

a) Diameter in mm :

i) Nominal ii) Minimum iii) Maximum

b) Cross sectional area of nominal

Diameter wire (Sq. mm.) c) Mass (Kg./Km.) d) Resistance at 20 Deg. C.

Maximum (Ohms./Km.)

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e) Breaking load (Min.) i) Before Stranding (KN)

ii) After Stranding (KN)

6. Steel wire used in construction of aluminium conductors, galvanised steel reinforced (ACSR) as per tables of IS:398(Pt.2)/1996

a) Diameter :

i) Nominal (mm) ii) Minimum (mm)

iii) Maximum (mm)

b) Cross sectional area of nominal diameter wire (Sq.mm.)

c) Mass (Kg./Km.) d) Breaking load (Min.)

i) Before Stranding (KN)

ii) After Stranding (KN) 7. Aluminium conductor galvanised steel

reinforced as per tables of IS:398 (Part.2)/1996 :

a) Nominal Al. area (Sq.mm.) b) Stranding and wire dia.

i) Aluminium (mm) ii) Steel (mm)

c) Sectional area of Al. sq.mm. d) Total sectional area sq.mm. e) Approx. overall diameter mm. f) Approx. Mass (Kg./Km.). g) Calculated resistance at

20 Deg. C. (Max.)(Ohms./Km.) h) Approximate calculated breaking load (KN)

8. a) Zinc coating of steel wire IS:4826/ 1979 with latest amendments.

i) No. of one minute dip. ii) No. of half minute dip.

b) Minimum weight of Zinc Coating

Gm./Sq. mtr.

9. Standard length in Meter

10. No. of the short lengths as per

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Clause No.10 of specification of Schedule-III

11. Total length in one drum

12. Net Mass of conductor in one drum (Kg.)

13. Tare Mass of the drum with lagging (Kg.)

14. Gross Weight of the drum including weight

of the conductor (Kg.)

15. Wooden Drums for ACSR ` Conductor :

i) Flange dia.

ii) Barrel dia.

iii)Traverse

16. Other particulars if any.

SIGNATURE

RUBBER SEAL & Date

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TECHNICAL SPECIFICATION FOR LT XLPE INSULATED ACSR RABBIT CONDUCTOR SUITABLE FOR WORKING VOLTAGE UPTO AND INCLUDING 1100 VOLTS

1. SCOPE:

This section provides for manufacture, testing before dispatch, supply and delivery F.O.R. destination of ACSR Rabbit Conductor, Cross linked polyethylene Insulated and suitable for working voltage upto and including 1100 Volts. The ACSR Rabbit Conductor shall be conforming to IS:398(Pt.2)/1996 with latest amendment and the insulation (XLPE) conforming to requirement given in Table-1 of IS:14255/1995 with latest amendments. However, the insulation (XLPE) shall be U.V. Resistant which shall be ensured by adding 2.5 +/- 0.5% Carbon Black in XLPE in well dispersed manner.

The bidders should be a manufacturer of ACSR RABBIT Conductor and also of XLPE Insulated Aerial Bunched / Power Cables. The Offers from sole selling agents / authorized dealer shall not be entertained. The firms (manufacturers) must posses valid ISI License for the ACSR Rabbit Conductor as per IS:398(Pt.2)/1996 as well as XLPE Insulated Aerial Bunched (As per IS:14255/1995) / Power Cable ( As per IS:7098(Pt.1)/1988 with latest amendment.

2. STANDARDS:

Unless otherwise stipulated in this specification the following standards with latest amendments shall be applicable for Insulated ACSR Rabbit Conductor

i) IS:398 (Pt.2)/1996 : Specification for Aluminum Conductor for overhead transmission line.

ii) IS:14255/1995 : Aerial Bunched Cable for working voltage upto & including 1100 V.

iii) IS:10810 : Methods of test for cables.


v) CENELAC HD 626 : Over head distribution cables of

S1 A1/A2 2002 rated voltage Uo / U(Um) : 0.6/1

(1.2) KV.

475

NOTE: The specification has mostly considered references from Indian Standard. However, reference have also been derived from the above referred International Standard in meeting the onerous site requirement of Jaipur Discom.


i) Peak ambient temperature in shade. 50 Deg.C

ii)

Maximum average ambient temperature in a 24 hours period in shade.

40 Deg.C

iii)

Min. ambient air temperature in shade

(-)5 Deg.C

iv)

Maximum temperature attainable by an object exposed to sun.

60 Deg.C

v)

Maximum relative humidity

100%

vi)

Average number of thunder storm days per annum

40

vii)

Average number of rainy days per annum.

100

viii)

Average annual rainfall

10 to 100 cm

ix)

Number of months of tropical monsoon conditions

4 months

x)

Maximum wind pressure.

100 Kg/ Sq. mm

xi)

Altitude not exceeding

1000 M

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4 GENERAL REQUIREMENT OF LT XLPE INSULATED ACSR RABBIT CONDUCTOR:

4.1 MATERIAL

A) FOR ACSR RABBIT CONDUCTOR

The material offered shall be of the best quality and workmanship. The conductor shall be constructed of hard drawn aluminum and galvanized steel wires which have the mechanical and electrical properties specified in IS: 398 (Part.2)/1996 with latest amendment, if any, the Zinc coating on the galvanized steel wires may be applied by the hot process in accordance with IS:4826/1979 with latest amendment if any. The ACSR RABBIT to be used shall be BIS marked.

B) FOR XLPE INSULATION

The Conductor shall be provided with cross linked polyethylene insulation applied by extrusion conforming to the requirement given in Table-1 of IS:14255/1995 with latest amendment. The insulation shall be so applied that it fits closely on the conductor and it shall be possible to remove it without damaging the conductor. The nominal thickness of insulation shall be of 1.5 mm. as per Clause No.7.2 of IS: 14255/1995 and the smallest of measured value of thickness of insulation shall be as per Clause No.7.3 of IS:14255/1995. The Colour of the insulation (XLPE) shall be Black with UV Resistance for which Carbon Contents 2.5 +/- 0.5% shall be added to XLPE in well dispersed manner.

5. TEST AND TYPE TEST CERTIFICATES:

5.1 The insulated conductor shall be conformed to requirement of latest edition of IS:398 (Part.2)/1996, for ACSR Rabbit Conductor. The XLPE Insulation shall conform the requirement of IS:14255/1995 with all subsequent amendments issued from time to time.

5.2 The material offered (XLPE Insulation with Carbon Contents 2.5 +/- o.5% in well dispersed manner) shall be fully type tested as per relevant standard of specification of IS:398(Pt.II)/1996 for ACSR Rabbit Conductor and XLPE Insulation conforming to requirement of IS:14255/1995 with all subsequent amendments issued time to time. The bidder shall furnish valid type test report of similar rating and design of tendered material along with bid as detailed at Schedule-III A.

The following shall constitute type tests as per requirement of IS–398 Part 2/1996 and IS-14255/1995 amended up to date.

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A) ACSR RABBIT CONDUCTOR (IS-398 Part-2/1996) AMENDED UP TO DATE

i) Measurement of Dia meter for individual Aluminum and steel wires

ii) Measurement of lay ratio

iii) Breaking Load of individual Wires.

iv) Ductility test

v) Wrapping test

vi) Resistance Test

vii) Galvanizing test. B) ON XLPE INSULATION (IS-14255/1995 AMENDED UPTO DATE

I) Test for thickness of insulation

II) Physical tests for insulation: a) Tensile strength and elongation at break

b) Ageing in air oven c) Hot set test d) Shrinkage test e) Water absorption (gravimetric) f) Carbon Black :

i) Content --- 2.5 +/- 0.5% ii) Dispersion --– Well dispersion.

III) Insulation resistance (volume resistivity test)

IV) High Voltage Test on Core immersed in water (duration of immersion > 1 Hour) and apply test Voltage 3.5KV AC for 5 Minutes (Test Method as per CENELAC HD 626 S1/ A1/A2 2002)..

5.3 The bidder must also clearly indicate various testing facilities available at their works for testing the material as per relevant standards. In case of otherwise particulars of the place where such testing is proposed to be conducted during the course of inspection shall be indicated with the offer.

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6. INSPECTION:

6.1 The inspection may be carried out by the purchaser at any stage of manufacture. The successful bidder shall grant free access to the purchaser’s representative at a reasonable time when the work is in progress. Inspection and acceptance of any equipment / material under this specification by the purchaser shall not relieve the supplier of his obligation of furnishing equipment in accordance with the specification and shall not prevent subsequent rejection if the equipment / material is found to be defective.

Following acceptance tests shall be done as per IS:14255/1995for XLPE Insulation suitable for working voltage upto & including 1100 Volts and as per Clause No.14.2 of IS:398 (Part.2)/1996 for ACSR Conductor shall be conducted in presence of the purchaser’s authorized representative / agency on each lot of offered insulated ACSR Conductor. The sampling shall be done as per Annexure-A (Clause No.10.2.1) of IS-14255/1995 for finished Insulated ACSR Conductor suitable for working voltage upto & including 1100 Volts:

(A) FOR XLPE INSULATION:

a) Test for thickness of Insulation. b) Tensile Strength & elongation at Break Test for Insulation. c) Hot Set for Insulation. d) Insulation Resistance Test. e) High Voltage Test. f) Carbon Black :

i) Content --- 2.5 +/- 0.5% ii) Dispersion –-- Well dispersion.

(B) FOR ACSR RABBIT CONDUCTOR:

i) Measurement of dia of individual Aluminum & Steel Wire. ii) Measurement of Lay Ratio. iii) Breaking Load of Individual wires. iv) Ductility Test. v) Wrapping Test. vi) Resistance Test. vii) Galvanizing Test.

The routine test certificates to be furnished to the Inspecting Officer at works as per IS-398 Part-2/1996 for ACSR RABBIT Conductor and as per IS:14255/1995 for XLPE Insulation amended up to date for verification.

479

6.2 The supplier / manufacturer must offer conductor for inspection through a letter of offer mentioning size and quantity of the conductor along with Packing List duly signed indicating drum Serial No. individual lengths total length, net weight & gross weight in DUPLICATE. This letter of offer shall be addressed to this office. The packing list shall also be furnished to the Inspecting Officer prior to carrying out the inspection at the works.

6.3 The supplier shall keep the purchaser informed in advance about the manufacturing programme so that arrangement can be made for inspection.

6.4 The purchaser reserves the right to insist for witnessing the acceptance / routine test of the bought-out items.

6.5 At least 5% of total nos. of drums subject to minimum of one (1) in any lot put up for inspection shall be selected at random to ascertain the length of insulated conductor by the following method:

“At the works of the manufacturer the insulated conductor shall be transferred from one drum to another for checking any manufacturing defects in the insulated conductor, at the same time measuring its length with the help of the graduated pulley & cyclometer. The difference in average length thus obtained from the declared length by the supplier in the packing list shall be applied to all the drums if the insulated conductor is found short during checking the sample lot(s).”

6.6 The supplier shall present the latest Calibration Certificate(s) of testing instruments / equipments to be used for the testing of the material covered in the Purchase Order to the authorized inspecting officer / inspecting agency of the purchaser. The testing instruments / meters/ apparatus etc. should be got calibrated by the supplier from time to time from Govt. or Independent test laboratory / house having valid accreditation from National Accreditation Board for Testing and Calibrating Laboratories for the testing equipments or original manufacturer having traceability to NABL / NPL or equivalent accredited lab.


480


7.2 The standard length of the insulated ACSR RABBIT conductor drum shall be 1000 meters. A tolerance of (+/-) 5% on the standard length offered by the Bidder shall be permitted. All length outside this limit of tolerance shall be treated as random lengths.

7.3 Random lengths will be accepted provided no length is less than 80% of the standard length and the total quantity of such random length shall not be more than 5% of the total quantity ordered.

7.4 The maximum length in one drum shall be 3000 meter. 8.1 TEST CHECKING OF MATERIAL AT STORES:

i) Sample drums from the material received at stores shall be selected for testing at CTL as per sampling plan given hereunder in presence of firms representative..

ii) The selected sample drum for CTL testing shall be identified by the seals provided by Inspecting Officer / Inspecting Agency during pre-dispatch inspection at firms works and these sealing details shall be invariably mentioned in the selection Memo by the nominated officers of Nigam.

iii) The tests in the Nigam Testing laboratory (CTL) shall be conducted in the presence of

representative of supplier for which a 7 days notice shall be issued through Fax / Speed Post stating Date & Time to the firm, so that supplier can depute their representative to witness the test . In case the supplier or his representative does not turn up the testing shall be proceeded & completed. The payment shall be released only after receipt of successful CTL test reports for the samples selected at purchaser’s stores for mandatory test checking on the samples to be selected from material received at Nigam’s stores by officers to be nominated by Circle SE’s / SE (I&S) for testing at CTL.

iv) One drum out of each lot / sub-lot of 25 Nos. drums or part thereof for LT XLPE Insulated

ACSR Rabbit Conductor received in Nigam Stores. The selected sample drum / drums shall be transported to CTL by concerned ACOS / SS.

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v) TESTS:

The following tests shall be carried out on each selected drum by drawing sample of 10 Mtrs. at CTL from random distance from any length of the selected drum of Insulated ACSR Conductor during rewinding the sample drum :

a) Rewinding Test (Measurement of Length) & checking of Manufacturing Defects.

b) Measurement of lay ratio of Bare Conductor during rewinding of Conductor Drum.

c) Measurement of dia of Aluminum & Steel Strands. d) Breaking Load as per IS:398(Pt.2)/1996. e) Galvanizing of Steel Wire Test (Uniformity ) and Mass of Zinc

Coating.

f) Measurement of Resistance of Conductor as per IS 398 Part-2/

1996 amended up to date.

g) Tensile and Elongation test for insulation as per IS-14255/1995

amended up to date.

h) Thickness of Insulation as per IS-14255/1995 amended up to date.

i) Hot Set (for XLPE Insulation) as per IS-14255/1995 amended up to

date.

j) Verification of marking.

NOTE: In addition to above tests remaining acceptance tests as per relevant IS shall also be conducted at CTL provided the testing facility is available at CTL for these tests time to time. Only those tests shall be conducted for which testing facilities are available in NIGAM’s Lab.

(a) The Officer In charge of central Testing Lab (CTL) of Nigam shall send copies

of test reports to the Purchasing Officer / Sr. AO (CPC), consignee and the supplier.

(b) The payment of every lot shall be released after receipt of successful test

report from Nigam’s Lab (CTL) on the samples selected from the material received in Nigam stores.


a) Rewinding Test (Measurement of Length):

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The results of measurement of length test shall be made applicable to all drums contained in each lot/sub-lot by making deduction of less length of conductor in a sample drum. . Incase short length is observed more than 1% of the length contained in Lot/Sub-lot then the lot /sub-lot shall liable to be rejected.

b) If the sample(s) fails in any above tests, the material shall be rejected and shall have to be replaced by the supplier.

c) All test charges incurred towards test checking of the material received in stores shall be borne by the Nigam.

d) If the contractor / supplier fails to lift the material declared rejected or any part thereof from the consignee within a period of 15 days from the date of dispatch of information from the purchaser, the purchaser shall be entitled to effect recovery along with other actions as per Clause No. 1.62 of Section-II (General Condition of Contract).


The XLPE Insulated ACSR RABBIT Conductor shall be wound on a non returnable wooden drum conforming to IS: 10418/1982 of suitable size.

The conductor drums shall carry the following information either stenciled or painted.

i) Manufacturer’s name, Brand or trade mark. ii) Type of Insulated Conductor and voltage grade. iii) Nominal cross-sectional area of the Insulated Conductor. iv) Length of Insulated Conductor on the drum v) Number of lengths on the drum (if more than one). vi) Direction of rotation of drum (by means of an arrow). vii) Gross mass. viii) Year of manufacture. ix) IPDS / tender No. and x) Name of Consignee.


The bidder shall furnish guaranteed technical particulars in the Performa of GTP enclosed at Schedule – VA & VB.

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11. MANUFACTURER:

The bidder should be a manufacturer of ACSR Rabbit Conductor and XLPE Insulated Aerial Bunched / Power Cables. The inspection / Testing shall be carried out at manufacturer works.

12. IDENTIFICATION:

i) The manufacturer shall be identified throughout the length of LT XLPE Insulated ACSR Rabbit Conductor by providing legible Embossing as under:

ii) EMBOSSING

The LT XLPE Insulated ACSR Rabbit Conductor shall also be required to be embossed with the word Manufacturer’s Name or Trade Mark, Electric, Voltage Grade, JAIPUR DISCOM or JVVNL / IPDS/TN-----, Size of Conductor, XLPE 90 & year of manufacture at every meter length for which no extra charges shall be paid.

iii) MARKING

The progressive length of LT XLPE Insulated ACSR Rabbit Conductor in meter shall be marked on every meter length of LT XLPE Insulated ACSR Rabbit Conductor.

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Schedule-III

3.1) TYPE TEST CRITERIA :

a. The bidder shall furnish valid and authenticated type test certificate from a Govt. approved / Govt. Recognized / NABL Accredited laboratory / ILAC i.e. International laboratory Accreditation Corporation (In case of foreign laboratory) / of similar rating and design (with Carbon Contents 2.5 +/- 0.5% in XLPE in well dispersed manner) of tendered material / equipment. Such type test certificate should not be older than Five years as on the date of bid opening For this purpose date of conducting type test will be considered.

The type test certificate by in house laboratory of biding firms even if it is Govt. approved / Govt. recognized / NABL Accredited laboratory / ILAC accredited , shall not be accepted, in case of their own bid. This will not apply if biding firm is Govt. company / public sector undertaking.

b. The bidder should furnish documentary evidence in support of laboratory whose type test have been furnished, that the said laboratory is a Govt./ Govt. approved / Govt. recognized / NABL Accredited laboratory / ILAC accredited (In case of foreign laboratory).

c. The type test certificate shall be furnished either in original or copy duly attested by Notary.

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SCHEDULE – VA

GUARANTEED TECHNICAL AND OTHER PARTICULARS OF LT XLPE INSULATED ACSR RABBIT CONDUCTOR

(A) FOR ACSR RABBIT CONDUCTOR

1. Manufacturer’s name

Office address

Works address

Telephonic address

Telephone

Fax

Telex

2. Standard according to which the conductor will be manufactured & tested

As per IS:398/1996 (Part.II) with latest amendments

3.

Whether conductor offered bears BIS Standard Mark.

If Yes, furnish copy of registration certificate of Bureau of Indian Standards

4.

Aluminium Wires used in the construction of aluminium conductors, galvanized steel reinforced (ACSR) as per tables of IS:398/Part.II/1996

a) Diameter

i) Nominal (mm) 3.35

ii) Minimum (mm) 3.32

iii) Maximum (mm) 3.38

b) Cross sectional area of nominal dia, wire (Sq. mm)

8.814

c) Mass (Kg/Km) 23.82

d) Resistance at 20 Degree C. maximum (Ohms/ Km.)

3.265

e) Breaking load (Minimum)

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i) Before stranding (KN) 1.43

ii) After Stranding (KN) 1.36

5.

Steel Wires used in the construction of aluminium conductors, galvanized steel reinforced (ACSR) as per tables of IS:398/Part.II/1996

a) Diameter

i) Nominal (mm) 3.35

ii) Minimum (mm) 3.28

iii) Maximum (mm) 3.42

b) Cross sectional area of nominal dia, wire (Sq. mm)

8.814

c) Mass (Kg/Km) 68.75

d) Breaking load (Minimum)

i) Before stranding (KN) 11.58

ii) After Stranding (KN) 11.00

6. Aluminium conductor galvanized steel reinforced as per tables of IS:398/(Part.II/ 1996)

a) Nominal Aluminium area (Sq. mm) 50

b) Stranding and wire diameter

i) Aluminium (mm) 6/3.35

ii) Steel (mm) 1/3.35

c) Sectional area of Aluminium (Sq. mm) 52.88

d) Total sectional area (Sq. mm.) 61.70

e) Approx. Overall diameter (mm) 10.05

f) Approx. mass (Kg./Km.) 214

g) Calculation resistance at 20 Degree C (Max.) (Ohms/Km.)

0.5524

h) Approx. Calculated breaking load (KN) 18.25

7. a) Zinc coating of steel wire (IS:4826/1979 with latest amendment)

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i) No. of 1 minute dip 3

ii) No. of ½ minute dip -

b)

Minimum weight of zinc coating (Gm/Sq. mtr.) 237.5

8. XLPE INSULATION : LT

a)

Thickness of Insulation:

i) Smallest measured value ii) Nominal measured value

1.25

1.5

b) Weight of XLPE Kg./Km To be furnished

c) Carbon Contents & its dispersion 2.5 (+/-) 0.5% well dispersed

d) Applicable standard for XLPE Insulation IS-14255/1995

9. a) Standard length of insulated conductor in meters

1000

b) Tolerance in standard length +/-5%

10.

No. of the short length(s) i.e. 80% length of standard length will be limited to 5% of the total ordered quantity.

As per Clause No.7 of Specification

11. No. of standard lengths in Drum To be furnished by bidder

12.. Total length of insulated conductor in one drum (Kms)

Upto 3 Kms

13. Net mass of Insulated conductor in one drum (Kg.)


14. Tare mass of the drum with lagging (Kg.) To be furnished by bidder

15. Gross weight of the drum including weight of the Insulated Conductor (Kg.)


16. Size and dimension of Drum as per IS:10418 / 1982 latest amendments


Note : Bidder are required to furnish value of each parameter. The word i.e. to be furnished later on, etc., or as per IS, shall not be allowed and offer liable to be ignored.

Date:

SIGNATURE

RUBBER SEAL

488

TECHNICAL SPECIFICATION FOR PURCHASE OF 3.15 MVA 33/11 KV POWER TRANSFORMERS

1.0 SCOPE :

This specification covers the design, manufacture, stage inspection and testing at the manufacturer's works before dispatch, supply and delivery at the destination in area of Jaipur Discom of 33/11KV Power Transformer having ratings of 3.15 MVA.


Max. ambient air temperature. 50 degree C.Max. daily average ambient temp. 45 degree C.Max. yearly weighted ambient temp. 35 degree C.Min. ambient air temp. (-) 5 degree C.Max. humidity. 100%Average number of thunder storm days per annum.

40

Average annual rain fall. 15 cm to 100 cm.No. of months during which tropical monsoon conditions prevail.

4 months (June to Sept.)

Maximum wind pressure 195 Kg./Sq.MAltitude above MSL Varies from 61 meters to

815 metersAverage number of rainy days per annum.

120 days.

3.0 GENERAL REQUIREMENTS :

The intention of the specification is to provide information for the design of the above mentioned 33/11 KV power transformers to be fully suitable in every respect for the functions designated. It is required that the supplier in accepting the contract agrees to furnish all apparatus, appliance and material whether specifically mentioned or not, but which may be found necessary to complete, perfect, or test any of the herein specified units in compliance with the requirements implied in this specification without extra charges.

3.1 All terminal screws, studs, nuts and bolts shall be in accordance with the

Indian Standards. 3.2 All electrical and mechanical equipments shall be designed and

manufactured so that no damage will result from transportation, installation and operation of the equipment under the climatic conditions to which it will be subjected.

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3.3 All materials used shall conform to this specification and appropriate standards and shall be new in all respects.

3.4 Consideration may be given to alternatives which the supplier considers

advisable by reason of his own manufacturing requirements and experiences, provided descriptive matter is submitted and the recommended device or arrangement equal to, or superior to that required by the accompanying specification and if the purchaser is convinced of the quality and/or superiority of the equipment.

4.0 STANDARDS :

The power transformers, their accessories and fittings, transformer oil, etc. shall conform to the latest edition of the following standards (as amended upto date) except where specified otherwise in this specification :

IS:5/1961: Colour for ready mixed paints IS 2026 (Part 1): 2011 GENERAL (Second Revision); IS 2026(Part2):2010 Temperature Rise (First Revision); IS 2026 (Part 3): 2009 Insulation Levels, Dielectric Tests and External clearance in Air (Third Revision); IS :2026 (Part IV)-1977 Reaffirmed 2011 – Terminal Markings, Tapping and Connections; IS 2026 (Part 5):2011 – Ability to withstand short circuit. IS:6600/1978:Guide for loading of oil immersed Transformers IS:335/1983:New insulation oils for Transformers IS:3347(PART-III/Sec-1 & 2): Dimensions of Porcelain parts

& Metal parts for Transformer bushing (17.5 KV).

IS:3637: Gas & Oil operated Relay. IS:3639/1966: Fittings & accessories for Transformers IS:1866/1978: Code of practice for maintenance & supervision

of insulating oil in service. IS:9335: Specifications for insulating craft paper. IS:1576: Specifications for solid insulating press Boards for

electrical purposes. IS:104: Ready mixed paint, brushing zinc chromate, painting IS:649: Testing of steel sheets and strips for magnetic circuits. IS:2362: Determination of water content in oil for porcelain

bushing transformers. IS:4257: Dimensions for clamping arrangements for bushings. IS:6160: Rectangular conductor for electrical machines. IS:10028: Selection, Installation and maintenance of transformers IS:3401 : Silica gel IS:5561: Terminal Connector IS:2070: Method of impulse voltage testing

4.01 Equipment meeting the requirements of any other authoritative standards which ensures a quality equal to or better than that as per the standards mentioned above, shall also be acceptable. Where the equipment conforms to any other standards, salient points of difference between the standards adopted and the specified standards shall be clearly brought out in the tender.

490

5.0 TROPICAL TREATMENT :

Under the climatic conditions prevalent at the site, the equipment supplied under the specification will be subjected to operation under the ambient temperature specified under clause 2.0 and very high relative humidity. All equipments shall, therefore be suitably designed and tested for normal life and satisfactory operation under the extreme climatic conditions prevalent at the site and shall be dust and vermin proof. All parts and surfaces which are subjected to corrosion shall be made of such material and shall be provided with such protective finishes as would protect the equipment installed from any injurious effects of excessive humidity. All electrical auxiliary equipment shall be specifically tested for tropical conditions and the materials for this treatment shall be as per modern engineering practices.

6.0 ELECTRICITY RULES :

All work shall be carried out in accordance with the latest edition of the Indian Electricity Act-1910, Electricity supply Act-1948, Electricity Act-2003, Electricity rules-2005 and rules formed there under and as amended from time to time.

7.0 TYPE AND RATING :

7.1 The transformers shall be of 3 phase, copper wound, core type construction,

oil immersed and shall be suitable for outdoor service as step down transformers ( At times however these may be required to work under reversal of power also).

7.2 These transformers may be required to run in parallel with existing

transformers of the similar capacity. The technical particulars of transformers required are as under:

i) Maximum continuous rating at reference : 3.15MVA ambient temperature specified under clause 3.02

ii) Frequency : 50 Hz

iii) No. of phases : 3 phase

iv) Rated primary Voltage on principal : 33 KV

tapping

v) Rated secondary Voltage : 11 KV

vi) Winding connections: a) HV side : Delta b) LV side : Star c) Vector group reference : Dyn11

vii) Type of cooling : ONAN

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viii) Percentage impedance at normal voltage & 75 deg.C average winding temp.(on 20 MVA base) between HV-LV at.-

Tap No. 3.15 MVA Tolerancea) Normal tapping(Tap-3)

7.00 % ± 10%

b) At max. tapping (+5%)

6.65% ± 15%

c) At min.tapping (-10%)

7.70% ± 15%

However, firm already having valid type tests with the following impedance value on the date of opening of Techno-commercial Bid then same shall also be acceptable:-

Tap No. 3.15 Tolerance

a) Normal tapping(Tap-3)

6.25% ± 10%


5.94% ± 15%

c) At min. tapping (-10%):

6.87% ± 15%

ix) Off circuit tap changer: Having 6 equal steps (7 position) of 2.5% of each, to have voltage variation of +5% to -10% on HV side.

x) Neutral unbalance : Not exceeding 2.0%

current xi) Type of terminal : Vertical take off type

suitable for ACSR "Panther" conductor on both sides.

xii) Max.current density in all parts: of HV and LV windings including 3Amp./Sq.mm tapped winding. for minimum tap in HV & LV.

xiii) Bushing metal part for HV & LV : M -20 size (copper/

bushing. brass)

8.0 EFFICIENCY :

The percentage loading for the max. efficiency shall be clearly stated in the tender at unity power factor as well as 0.8 p.f. lagging.

9.0 INSULATION :

9.01 The dielectric strength of the winding, given insulation and the bushings shall

conform to the values given in IS:2026(Part.3)/2009 (or its latest amendment) for

492

highest system voltage of 36KV,12KV and shall be suitable for the following impulse test \ power frequency test voltages.

SYSTEM VOL. H.SYSTEM VOL. IMPULSE TEST VOL. PF TEST VOL. ---------- ------------- ---------------- ------------

33 KV 36 KV 170 KVp 70 KV 11 KV 12 KV 75 KVp 28 KV

H.V. & L.V. Winding of Transformer shall have uniform insulation. 10.1 TEMPERATURE RISE :

Each transformer shall be capable of operating continuously at their normal rating without exceeding temperature rise limits as specified below :

---------------------------------------------------------------

Type of Temp.rise External cooling. cooling

medium (Air) ---------------------------------------------------------------

2 measured by thermometer method)

---------------------------------------------------------------

The reference temperature conditions for which the transformers shall be designed are as under (as per clause 3.02).

a) Maximum ambient temperature. : 50 degree C. b) Maximum daily average ambient temp. : 45 degree C. c) Maximum yearly weighted : 35 degree C.

ambient temperature.

The hottest spot temperature shall not exceed 98 degree C when calculated over an annual weighted average ambient temperature of 35 degree C when transformer is loaded to its rated capacity. The transformer shall be capable of being over loaded to 150% of its rating in accordance of IS 6600-1972.

i) Bushing and its terminal connectors shall have minimum continuous current rating corresponding to 120% rated current of transformer at lowest tap.

11.0 PARALLEL OPERATION :

The transformers covered by this specification are to run in parallel with transformers which are either already installed or are being installed (for same rating) and as such the characteristics of the transformers covered in this specification for the sub station will be identical so as to enable these transformers to run in parallel.

1. Winding( Temp.rise ONAN 50 degree C. When the oil measured by resistance circulation ismethod) natural non

directed . Oil ( Temp.rise As above. 45 degree C. -

493

12.0 IMPEDANCES :

Suppliers shall indicate the guaranteed impedances and tolerances taking into account the limits at minimum and maximum tap position so as to fulfill requirements of clause 11.0

13.0 GUARANTEED LOSSES:

13.1. The Losses shall not exceed the values given below:

----------------------------------------------------- Rating No load losses Load losses at

in KW 75 deg.C.in KW (At normal tap condition)

----------------------------------------------------- 3.15 MVA 3 KW 16 KW -----------------------------------------------------

The above mentioned losses are maximum permissible and there shall not be any plus tolerance above this limit. Design calculations of No-load and load losses along with complete Technical details and factors assumed will be enclosed Along with the GTP in tender documents.

13.2 In case during testing, the actual loss (es) are found within guaranteed figure, the

transformers shall be accepted without any advantage to contractor for lower losses. 13.3 Measurements of losses shall form part of type test/ routine test.

13.4 The losses on transformer supplied shall also be guaranteed at the time of pre-

commissioning test and transformers having losses exceeding figures mentioned in clause 13.0 above shall stand rejected.

13.5 The supplier shall supply two copies of the Routine test certificate to consignee

with each transformer on receipt of despatch instructions. 13.6 The supplier shall provide along with the tender the design details of core

assembly showing the construction details, core diameter, net/ gross sectional area of the core assembly etc. The information must also be given in respect of volts per turn at principal tap for normal voltage. The loss curves for type/grade of steel laminations being used for the core shall also be provided along with the tender.

14.0 COOLING :

14.1 Each transformer shall be provided with ONAN type cooling as specified under the

schedule of requirements.

494

14.2 The ONAN cooling of the transformers shall be by natural circulation of air while the circulation of oil shall be effected by natural convection, the maximum oil flow being assured by a method whereby the return flow of cooled oil is made to enter the tank at a level coinciding with the bottom of the hot columns of oil thus avoiding centre heads of cold oil at the bottom of the tank. Out flow shall be arranged to coincide as nearly as possible with the hot oil level at the top of the tank so that the total available difference will be fully employed in circulating the oil round the shortest possible paths.

14.3 The windings of the transformers shall be designed to deliver continuously rated

MVA corresponding to ONAN cooling.

Radiators shall be provided for cooling purpose. These shall be directly mounted on the tank on both sides in a balanced manner & not on one side only.

14.4 The Radiator to be used should be of PSR type for all three type of rating.

14.5 For heat dissipation calculation for tank surface at 45 Degree, 500 watt per Sq.

meter will be considered and for Radiator, heat dissipation will be worked out as per manufacturing chart provided by manufacturer, firm will enclose the chart.

14.6 The cooling arrangement shall consist of detachable radiators which may be directly

mounted on the transformers. Connections between the radiators and tank shall be made with flanges provided with gaskets and an indicating sheet valve provided at both connection ends, which can be fastened in either open or closed position.

14.7 The radiators shall be so arranged that these can be detached from the tank or bank

without disturbing the oil in transformer. These shall be designed to withstand the vacuum and pressure specified for the tank.

14.8 Radiators shall be so designed as to be for cleaning & painting to prevent

accumulation of water on the outer surface to completely drain oil from the tank or bank and to ensure against formation of gas pockets when the tank is being filled. All connections between the radiators and tank or bank and between the bank & tank shall be provided with flanges when the particular item is detached. Each radiator shall have a lifting eye, an oil drain and vent at top.

14.9 The height of the radiator should not be above the transformer tank & All the

Radiator shall be so arranged that they can be directly be connected to tank without any bend.

14.10 The indication regarding state of opening/ closing of radiator valve should be clearly identified through paint-marking.

15.0 TRANSFORMER CORE :

15.1 The core shall be built up with thin lamination of high grade, non ageing, low loss, high permeability, cold rolled, grain oriented silicon steel specially suitable for transformer core. The particulars of laminated steel to be

495

employed shall be supplied with the tenders along with DC magnetization, B- H and iron loss curves.

15.2 After being sheared the laminations shall be treated to remove all burrs and shall

be re-annealed to remove all residual stresses. At least one side of each lamination shall be coated with a double baked enamel insulation coating which will not deteriorate due to pressure and the action of hot oil. The nature of insulation shall be specified in the tender.

15.3 Every care shall be exercised in the selection, treatment and handling of core

steel to ensure that as far as practicable, the laminations are flat and the finally assembled core is free from distortion.

15.4 The design of the magnetic circuit shall be such as to avoid discharges, development

of short circuit paths within itself or to the earthed clamping structure and the production of flux components at right angles to the plane of the laminations which may cause local heating.

15.5 The core shall be rigidly clamped to ensure adequate mechanical strength and to

prevent vibration during operation. The core/clamping bolts shall not pass through Core/Yoke and clamping structure shall be so constructed that eddy currents will be minimum.

15.6 The core shall be provided with lugs suitable for lifting the complete core and coil

assembly of the transformer. The core and the coil shall be so fixed in tank that shifting will not occur when the transformer is moved or during a short circuit.

15.7 The core shall be of high grade cold rolled gain oriented annealed steel laminations, having low loss and good grain properties, coated with hot oil proof insulation, bolted together to the frames firmly to prevent vibration or noise. All core clamping bolts shall be effectively insulated. The complete design of core must ensure the permanency of the core losses with continuous working of the transformers. The value of the flux density allowed in the designs and grade of laminations used shall be clearly stated in the offer, along with the curves. The transformer core shall be constructed out of the prime class of materials. The transformer core shall be of prime quality CRGO steel. The bidder shall import the core directly or shall purchase directly from the imported and he will furnish the following documents at the time of stage inspection of the transformer:-

a) Invoice of supplier. b) Mill’s test certificate. c) Packing list. d) Bill of landing e) Bill of entry certificate by custom.

Description of material, electrical analysis, physical inspection, certificate for surface defects, thickness and width of the material.

496

15.8 FLUX DENSITY :

The flux density in any part of the core built from cold rolled grain oriented steel shall not exceed 16000 lines per sq. cm. at any tap position necessary to maintain No Load terminal voltage of 11KV on LV side as required. The transformer shall also be suitably designed to withstand upto 10% upward primary voltage variation at normal tap continuously without saturation and excessive heating of the core and windings. Due regard shall also be given to limiting the flux density based on the characteristics of the material used.

The tenderer shall furnish magnetization curve for material indicating max working flux density without saturation. The tenderer shall indicate max. flux density in core/yoke at rated voltage to establish that the max. flux density at 10% over voltage (with reference to nominal voltage) does not cause core saturation.

The design calculations in support of flux density shall be furnished by the tenderer along with drawing of cores steps and calculations of effective cross sectional area of the core. For finding out no load current, average values of all the three limbs and phases should be taken into consideration.

16.0 WINDING :

16.1 The windings shall be so designed that all coil assemblies of identical

voltage ratings shall be inter changeable and field repairs to the windings can be made readily, without special equipment. The coils shall be supported between adjacent sections by insulating spacers and bracers. Bracings and other insulation used in the assembly of the windings shall be arranged to ensure a free circulation of the oil and to reduce hot spots in the windings. The windings shall be designed to reduce to a minimum the out of balance forces in the transformer at all ratios.

16.2 The insulation of the coils shall be suitable to develop the full electrical strength

of the windings. All materials used in the insulation and assembly of the windings shall be insoluble, non catalytic, and chemically inactive in the hot transformer oil, and shall not soften or otherwise be adversely effected under the operating conditions.

16.3 All threaded connections shall be provided with locking facilities. All leads from

the windings to the terminal board and bushings shall be rigidly supported to prevent injury from vibration. Guide tubes shall be used where practicable.

16.4 The windings shall be clamped securely in place so that they will not be

displaced or deformed during short circuits. The assembled core and windings shall be vacuum dried and suitably impregnated. The electrolytic copper conductor used in the coil structure shall be best suited to the requirements and all permanent current carrying joints in the windings and the leads shall be welded or braced except compression type which may be used for terminal

497

connections. Bolted connection may be used at the bushings and at terminal board with suitable locking device. The drying out procedure of the core coil assembly shall be indicated in the tender.

17.0 FAULT WITHSTANDING CAPACITY OF WINDINGS :

All the windings shall be suitably designed to withstand short time rating for not less than 2 seconds by feeding the fault level of 1000 MVA on HV side, 750 MVA on 11 KV side respectively from both ends and considering the severe most form of system faults that can arise in service. Tenderer(s) should furnish the detailed calculations for thermal as well as dynamic ability of windings to withstand short circuits as prescribed above, failing which their quotations are likely to be ignored. The max. temp. attained for short time rating shall not exceed 250 degree C.

18.0 INSULATING OIL :

18.1 The oil for first filling shall be supplied with each transformer. The oil shall be

EHV grade-I and shall comply IS:335/1993 latest version & amendment. 18.2 Particular attention shall be paid to deliver the oil for topping up free from

moisture having uniform quality through out in the non-returnable new steel drums.

18.3 The quantity of oil for first filling of each transformer shall be stated in the

tender . Quantity of oil required for filling of conservator and radiators shall be stated in the guaranteed technical particulars.

18.4 The transformer oil purchased from M/s. Savita Chemical, M/s. Apar, M/s.

Raj Lubrichem, M/s. Raj Petroleum, M/s Tashkant, M/s Sharavathy, M/s Rinki/M/s Madras Petrochem and M/s. Lubrichem, M/s Columbia shall only be supplied. Invoice and test certificates of manufacturer of transformer oil shall have to be furnished as and when desired by the Nigam.

19.0 TANK :

19.1 The transformer tank and cover shall be fabricated from good commercial grade low

carbon steel suitable for welding and of adequate plate thickness. The tank and the cover shall be of welded construction. All seams shall be welded and where practicable they shall be double welded. The transformer tank shall have sufficient strength to withstand without permanent distortion. The punching on all 4 sides of Power Transformer tank with letter size of 10x5mm will be carried out. The details to be punched are as under:-

i) IPDS/TN No.

ii Serial No.

i) Make ii) Rating.

498

The thickness of tank sheet shall be as under:-

S.No. Dimensions of 3.15 MVA

i. Top Cover 8mm

ii. Side Cover 6mm

iii. Bottom Cover 8mm

19.2 At least one manhole/inspection cover with a welded flange and a bolted cover shall be provided on the tank cover. The manhole shall be of a sufficient size to afford easy access to the lower ends of the bushings, terminals etc.

19.3 All bolted connections to the tank shall be fitted with suitable oil tight gaskets

which shall give satisfactory service under the operating conditions. Special attention shall be given to the methods of making the hot oil tight joints between the tank and the cover as also between the cover and the bushing and all other outlets to ensure that the joints can be remade satisfactorily and with ease , with the help of semi-skilled labour. Where compressible gaskets are used, steps shall be provided to prevent over compression. Suitable guides shall be provided for positioning the various parts during assembly or dismantling.

19.4 Lifting eyes or lugs shall be provided on all the parts of the transformers

requiring independent handling during assembly or dismantling. In addition the transformer tank shall be provided with lifting lugs and bolts properly secured to the sides of the tank, for lifting the transformer either by cranes or by jacks.

19.4.1 The design of the tank, the lifting lugs and bosses shall be such that the

complete transformer assembly filled with oil can be lifted with the use of these lugs without any damage or distortions. The tank shall be provided with two suitable copper alloy, lugs for the purpose of groundings.

19.4.2 The main body of the tank shall have sufficient strength to withstand and without

permanent distortion

i) A vacuum of 760mm of mercury. ii) Continuous internal gas pressure of 0.7 atmosphere above atmosphere pressure

with oil at operating level i.e. the transformer tank should be able to withstand 100% vacuum and also one atmosphere pressure above atmosphere internal pressure.

499

19.4.3 The tank cover shall be belled to the tank and the transformer design shall be such that at the tank will not split between the lowest and upper cooler connections.

19.4.4 Each tank shall be provided with the following

a) Lifting lugs suitable for lifting the transformer complete with oil accessories

lifted with oil by cranes. b) A minimum of four jacking lugs, in accessible position to enable the

transformers complete with oil to be raised or lowered using hydraulic or screw jacks.

The minimum height of jacking lugs above base shall be

i) Transformer above 10 tonnes weight : 500 mm ii) Transformer upto and including 10 tons weight: 300 mm.

Horizontal plates with 50mm dia drew holes drilled therein shall be fitted adjacent to each corner of the rectangular tank at more than 750 mm from the base to permit haulage in any direction. On the rounded tanks drew holes shall be located on the diagonals of the rectangular formed by the overall boundaries of the tank.

19.5 Each tank cover shall be adequate strength and shall not distort when lifted.

Inspection opening shall be provided to give easy access to lower ends of bushings, terminals etc. for changing ratio or winding connection or testing to each connections. These shall be of adequate to size not less than 450mm x 350mm

19.6 Suitable guides shall be provided for positioning the various parts during

assembly or dismantling. Adequate space should be provided between the cores and winding and the bottom of tank for collection of any sediment.

19.6.1 The base channel for transformer shall be 250 x 6 x 82 mm.

19.6.2 Prismatic oil level gauge indicator on transformer tank shall be provided

to indicate level of oil in Transformer tank at a suitable place on LV bushing side.

20.0 UNDER CARRIAGE :

20.1 The transformer tank shall be supported on a structural steel base. 20.2 Pulling eyes shall be provided to facilitate moving the transformer and they

shall be suitably braced in a vertical direction so that bending does not occur when the pull has a vertical component.

21.0 OFF LOAD TAP CHANGER MECHANISM:

21.1 The off circuit tap changer shall be of high quality and robust in construction.

It shall be located at a convenient position so that it can be operated from ground level by a standing operator. The handle of OCTC shall be

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provided with a locking arrangement, thus enabling the OCTC to be locked in position. Arrangement for indicating of tap position shall also be provided. It shall be suitable for local manual operations. The tap changer shall be capable of permitting parallel operation with other transformer of the same type. When one unit is in parallel with another of same type as mentioned in clause No.11.0 under normal condition, the tap changer shall not become out of step. The OFF Load Tap Changer should be of following makes only:-

i) M/s Paragone Associates, Thane. ii) M/s Alwaye, Bangalore.

21.2 The OCTC shall be capable of carrying rated MVA on all taps. The breaking

capacity of the OCTC shall be compatible with the highest system voltage and current based on maximum over loading permissible under IS:6600 -1972 (150% of rated value). The voltage rating for each step shall be 2.5% on HV side. However, each step of OCTC shall withstand voltage not less than 115% of rated step voltage. The rated through current of OCTC at this voltage will not be less than 150% of rated current of HV winding at lowest tap.

22.0 CONSERVATOR:

22.1. Oil preserving equipment shall be conventional conservator tank type. The minimum oil level in the conservator tank shall not be below the level of the bushing flanges.

22.2 Oil conservator tank shall be located well clear of the bare connection of the

transformer terminals. The conservator tank shall have adequate capacity between highest and lowest permissible levels to meet the requirement of expansion of the total cold oil volume in the transformer and cooling equipment from min. amb. temperature to highest oil temp. as per desired.

22.3 The total volume of the conservator shall be min. 10% of the total quantity of

oil in transformer. The inside diameter of the pipe connecting the conservator to the main tank shall be min.50mm and it should be projected into the conservator in such a way that its end is projected 30mm above the bottom so as to create sump for collection of impurities. The min. oil level should be above the sump level.

22.4 A conservator complete with sump and drain valve shall be provided in such a

position as not to obstruct the electrical connections to the transformer, having a capacity between highest and lowest visible levels to meet the requirement of expansion of the total cold oil volume in the transformer and cooling equipment from the minimum ambient temperature shall be with 0 Deg. C to 90 Deg.C. The minimum indicated oil level shall be with the feed pipe from the tank covered with not less than 15mm depth of oil and the indicated range of oil level shall be minimum to maximum.

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22.5 The oil connection from transformer tank to the conservator vessel shall be arrange at a rising angle of 3 Deg. to 9 Deg. to the horizontal up to gas and oil actuated relay and shall consist of 50mm inside diameter pipe.

22.6 Each conservator vessel shall be fitted with a breather in which silica gel is the

dehydrating agent and designed so that a. The passage of air is through silica gel. b. The external atmosphere is continuously in contact with silica gel. c. The moisture absorption indicated by a change in colour of the tinted crystals can

be observed from distance. d. Breathers shall be mounted at approx. 1400 mm above ground level.

23.0 TEMPERATURE INDICATING DEVICE:

The tripping contacts of above temperature indicators shall be adjustable to close between 60 Deg.C and 120 Deg.C and alarm, contacts to close between 50 Deg. C & 10 Deg.C and both shall reopen when the temperature has fallen by above 10 Deg.C.

24.0 MARSHALLING BOX OR KIOSK

24.1 A sheet vermin proof well ventilated and weather proof marshalling box of the

suitable construction shall be provided for the transformer ancillary apparatus. The box shall have domed or sloping roofs and the interior and exterior painting shall be in accordance with specification.

24.2 The marshalling box, wherever provided shall accommodate the following equipments alternatively weather proof instruments can be mounted outdoor.

a. Temperature indicators. b. Terminal boards and gland plates for incoming and out going cables.

24.3 All the above equipments except (b) shall be mounted on panels and back of panel

wiring shall be used for inter connection. 24.4 The temperature indicators shall be so mounted that the dials are not more than

1600 mm from ground level and the door (s) are of adequate size. 24.5 To prevent internal condition an approved type of metal clad heater shall be provided

controlled by a suitable switch. Ventilation louvers shall be provided. 24.6 All incoming cables shall enter the kiosk from the bottom and the gland plate shall be

not less than 450mm from the base of box. The gland plate and associated compartment shall be sealed in suitable manner to prevent the ingress of moisture from the cable trench.

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25.0 DIAGRAM AND RATING PLATE

Each transformer shall be provided with a non-detachable brass or stainless steel plate mentioning complete information as given in clause 7 of latest version of IS 2026 (Part 1): 2011 and diagram of winding connection and taps shall be provided. The property of respective Discom and IPDS/TN. shall be engraved on the plate Guaranteed values of No-Load loss and Load loss at 75 Deg.C without and plus tolerance along with measured values as well as temperature rise figures should also be inscribed on the diagram and rating plates.

26.0 BUSHINGS :

26.1 All main winding and neutral leads for 33/11 KV transformers shall be brought out through outdoor type bushings. The electrical characteristics of bushing shall be in accordance with IEC-137 as well as IS-3347/8603 and IS- 2099. The bushing shall be rated for highest voltage and current rating of the respective windings. The current ratings of bushing shall be at least 150% of the rated current at minimum tap to permit overloading.

26.2 The bushings shall have high factor of safety against leakage to ground and

shall be so located as to provide adequate electrical clearances between bushings and between the bushings and ground parts. The spacing between the bushings shall be adequate to utilize full flashover strength preventing flashover between the phases or between phase and ground parts under all conditions of operation. The creepage distance of bushing shall not be less than 25 mm per KV.

26.3 All bushings shall be equipped with suitable solder less terminals of

approved type. The type and size shall be specified in the tender. All external current carrying contact surfaces shall be placed adequately.

26.4 Bushings of identical voltage ratings shall be interchangeable .

26.5 Special adjustable arcing horns shall be provided with HV & LV bushings. Each

bushings shall be so coordinated with the transformer insulation that all flashover occur outside the tank.

26.6 All porcelain used in bushings shall be of the wet process homogeneous

impervious to moisture and free from cavities or other flaws and throughout vitrified and smoothly glazed. The glazing shall be of the uniform colour and free from blisters, burns and other defects. All bushings shall have puncture strength greater than the dry flashover voltage.

26.7 The crepage distance of 33 KV bushing surfaces shall not be less than 900 mm & for 11 KV shall not be less than 300 mm.

26.8 Terminal conductor of HV & LV shall be vertical take off type and suitable for ACSR PANTHER.

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27.0 (A) SUPPRESSION OF HARMONICS:

The transformer shall be designed with particular attention to the suppression of harmonics voltages especially in the third & fifth harmonics so as to eliminate wave form distortion and any possibility of high frequency disturbances.

27.0(B) MARKING

All transformers shall have the marking in paint on the body for identification as per Indian Standards or as instructed by purchaser.

28.0 CENTRE OF GRAVITY.

The centre of gravity of the assembled transformer shall be low and as near the vertical centre line as possible. The transformer shall be stable with or without oil. If the centre of gravity is eccentric relative to track either with or without oil its location shall be shown in the outline drawing in all the views showing their position of Transformer track also.

29.0 FITTINGS AND ACCESSORIES :

29.1. Each transformer shall be provided with the following fitting and accessories in

accordance as specified in IS:2026:

(i) Oil Temperature Indicator (OTI) The transformer shall be provided with one 150 mm dial type, oil Temperature Indicator for indicating top oil temperature. The indicator shall have adjustable electrically independent ungrounded alarm and trip contacts with Micro Switches and maximum reading pointer. The temperature-sensing element shall be suitably located in a pocket on the top of the transformer and shall be connected to the oil temperature indicator by means of capillary tubing protected with a metal sheath. The accuracy class of the OTI shall be +/- 1%

Suitable contacts shall also be provided for remote indication of oil temperature.

(ii) Winding Temperature Indicator:-

The Transformer shall also be provided with a device for indicating the temperature of winding (HV and LV separately). It shall comprise the following:-

a) Temperature sensing element suitably located on the top cover of the transformer. b) 150 mm dial, local indicating instrument with maximum reading pointer, mounted in

the cooler control cabinet and two adjustable electrically independent ungrounded contacts with Micro switches (beside that required for control of cooling equipment). The tripping contacts shall be adjustable to close between 60 Deg. C and 120 Deg.C and alarm contacts to close between 50 Deg. C and 100 Deg. C and both shall reopen when the temperature has fallen by a desired amount between 5 Deg. C and 50 Deg.C. All contacts shall be adjustable on a scale. They shall be accessible on removal of the cover

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and it shall be possible to check the operation of the contacts and associated equipments. Connections from the contacts shall be brought down to the terminal Block, placed inside the marshalling box. The accuracy class of the WTI shall be +/- 1%.

c) Calibration device:


iii) One filter valve located at the top of the tank on the LV side. The opening of this valve shall be baffled to prevent aeration of oil.

iv) One drain cum filter valve with sampling valve for main tank with plug or core plate of suitable size with locking arrangement located near the bottom of the tank on the HV side of the transformer but diagonally opposite to LV side.

The above filter/drain valves shall be located on non-bushing side of the Transformer. It should be placed on bottom side of tap changer and on top of the diagonally opposite side.

v) Air release device. It shall be of adequate capacity and shall be provided to release the trapped air during/after filling of the oil.

vi) Explosion vent (Pressure release device).

vii) One No. double float Buchholz relay shall be provided with alarm and tripping contacts to detect accumulation of gas and sudden changes of oil pressure, complete with shut-off valves on either side and flange coupling to permit easy removal without lowering oil level in the main tank, a bleed valve for gas venting and a test valve. The Buchholz relay shall be of best indigenous make having ISI certification. Buchholz relay must be made of cast iron/ aluminum.

viii) Detachable radiators complete with shut off valves as necessary for cooling

as per clause 14.0.

ix) An oil conservator having detachable end plates, with following provisions.

a) Magnetic type oil level gauge:- The conservator shall be fitted with one magnetic oil level gauge with nitro-phyll float having:

i) Dial with minimum, maximum & normal (at 30 Deg.C) Oil level marking and a pointer. ii) Low Oil level alarm contacts of 0.5 Amp. 110V/ 30V DC.

b) One oil filling hole with plug and drain valve on the conservator.

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c) one prismatic oil level gauge having painted/embossed marking as min., normal, and max. oil level.

d) Silica gel breather with Oil seal and Dehydrating agent. x) Eye bolts and lugs on all parts for ease of handling.

xi) Two grounding terminals as per clause No.19.5.

xii) Rating, Diagram and terminal marking plates :

Rating, diagram and terminal marking plates of stainless steel or brass for transformers and other accessories giving details as per IS:2026 shall be provided. Value of full wave (1.2/50 micro second) impulse level, short circuit current. its duration, weights of all important items, Impedances, loss values at normal/extreme taps and Postal address. Performance guarantee clause 39.0 shall also be indicated.

xiii) All transformers shall have the marking in paint on the body for identification

as per Indian Standard or as instructed by purchaser. Further, the following should be embossed at the top of the tank cover.

a) Sr. No. of the transformer. b) IPDS/ TN No c) Name of the firm. d) Month and year of manufacture.

xiv) Bimetallic terminal connectors suitable for "ACSR Panther" for HV and LV

bushing and earthing clamps should be as per IS:5561.

xv) Suitable weather proof cubicles (Marshalling box) for housing the local control equipment for fans, terminal blocks, for current transformer secondary and for mounting winding temperature indicators and oil temperature indicator as (i) and (ii) above.

xvi) HV and LV bushings with adjustable arcing horns 3 Nos. and 4 Nos.

respectively. xvii) Triple pole type off load tap changer as per cl.no.21.0 xviii) Skids : xix) Hauling Eyes : Hauling eyes shall be provided on all the four sides of the

transformer base. xx) Jacking Pads :Four, sturdy jacking pads shall be provided for lifting complete

transformer. Lifting height and safe capacity of jacks shall be specified in Bid. xxi) Lifting Lugs : Two sets of forged or tested mild steel plate lifting lugs, one

set for top cover, core and coil assembly and other set of complete transformer shall be provided. Lifting lugs shall be of adequate strength and size for attaching steel rope slings. Should lugs for lifting complete transformer be located on the base, sling guides shall be provided on cover.

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xxii) Inspection Covers :One inspection covers of sufficient size for access to the interior of the tank shall be provided on the cover. The inspection covers shall be provided with suitable lifting arrangements.

All type of valves shall be of gun metal except radiator shut off valves which may be of cast iron/steel. All valves shall be provided either with blind companion flanges or with pipe plugs for protection.

The makes of fitting & accessories will be as under:-

S.No. Fitting & Accessories Makes

1 Buchholz relay Atvus, Sukrat, Suvidha.

2 Winding Temperature Indicator/ Oil Temperature Indicator

OTI/WTI Model integrated RTD Schemefor ROTI/RWTI with remote indicator ofM/s Preci Measure Control Pvt. Ltd./Thermal System, Belltek

3 Magnetic type oil level gauge Atvus, Sukrat, Instrument & Control

4 Radiator Valve Hari Industries, Atvus, Vinayak, Vimal Techno, Petsun, Kailash

5 Filter valve & Drain valve Zolote, L&T, G.G., Leader, Uttam, PunjabMetal (ELMS mark), Leader, Hari Ind., Newman Ind.

Radiator valves shall have clear & distinct OPEN/CLOSE indication embossed/ casted as well as painted on the both sides of main body of valve. Radiator valve should have zero leakage with cap remove.

The new makes of fitting & accessories may be accepted with the approval of SE(TW),JVVNL, Jaipur on the basis of ISI approval certificate/ tests reports from any NABL accredited Lab./Govt. Lab./ performance report from utilities.

29.2 LOCKING ARRANGEMENT

To curb the theft of oil from power transformers, the following parts are either required to be blocked/ plugged or provided under provisions of locking:-

S. No.

Transformer Part Mode of blocking

1. Conservator drain plug/ Cap shall be provided as per drawing `b’.

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valve

2. Both oil filtration valves Cap shall be provided as per drawing à’.

3. Transformer Oil drain valve.

Cap shall be provided as per drawing à’.

4. Radiator drain plug (Bottom)

Cap shall be provided as per drawing `c’.

5. Radiator Air release plug (Top)

Locking on top for which provision is to be provided by firm and informed to SE(TW) for approval.

6. Conservator filling hole. To provide locking arrangement for which provision is to be provided by firm and informed to SE(TW) for approval.

7. Air release plug on top cover.

To provide wire mesh cap arrangement so that only air can be released.

Drawing is enclosed.

30.0 FACTORY ASSEMBLY AND TESTS : 30.1 The transformer shall be completely assembled and tested at the Factory. It shall be

at the option of the purchaser to send a representative(s) for carrying out stage inspection and various tests during actual manufacture and assembly of transformer(s) so as to satisfy regarding the quality of product and material being used.

30.2 All Type and Routine tests as per specification are to be conducted and no deviation

in respect of conducting these tests will be acceptable. No extra charges for these tests will be paid. Test charges shall be part of cost of the equipment. Even if charges for such test are indicated elsewhere in the tender, it will be presumed that these tests will be conducted free of cost. If purchaser selects to send a representative, all tests shall be carried out in his presence.

31.1 STAGE INSPECTION :

Before carrying out the stage inspection the following documents shall be given to Inspecting Officer(s) for verification:

a) Invoice of supplier b) Mill's test certificate c) Packing list d) Bill of landing e) Bill of entry certificate by custom f) description of material, electrical analysis, physical inspection, certificate for

surface defects, thickness and width of the material.

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The purchaser's representative may carry out stage inspection of the transformers during manufacturing/ assembling stage. The purchaser shall have absolute right to reject the raw material/ component/ sub assemblies or complete equipment not found to be conforming to the requirement of the specification or being of poor quality/ workmanship. The stage inspection will particularly include following tests/ check besides the general routine tests to be conducted during manufacturing stages as per manufacturer's standard practice.

a) Physical inspection/checking of winding insulating material, core material and

other accessories/fitting of transformer. b) Measurement of core area, cross sectional area of winding(s), number of turns in

each winding. c) Verification of HV and LV Coils, conductor size, I.D., O.D., Axial Length, Weight,

Insulation covering etc. d) Measurement of thickness of tank plates (Bottom and sides) and to conduct

pressure & vacuum tests as per CBIP manual for transformer tests to ensure the adequate strength of tank plates.

e) Sample testing of core material for checking specific loss, magnetization characteristics

(i.e. B.H. Curve plot) and thickness. f) Visual and dimensional check during assembly stage of core.

g) high voltage test(2KV,50Hz for one minute) between all core-bolts if provided and

agreed to frame bars/fish plates etc. and ferro-magnetic steel of core. h) Check on completed core for measurement iron loss and check for any hot spot by

exciting the core so as to induced the design values flux density. i) Check for proper provisions of spacers and bracings to arrest the movement of core

and winding assembly inside the tank. j) Check complete transformer against approved outline drawing, provision for all

fittings, finish oil level etc.

The purchaser at his option may collect the sample of the following raw material/ component for independent testing:

a) CRGO

Laminations One specimen sheet of 300-500mm length and 50-75mm width (for each lot).

b) HV winding wire 1250 mm length specimen for each type c) LV winding wire 1250 mm length specimen for each type d) Transformer oil 2 samples of 5 litres each.

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To facilitate stage inspection, the supplier should intimate complete schedule of manufacturing programme of the transformers at least 15 days in advance to the SE (MM) of respective Discom. At least 50% of the transformers shall be offered in the shape of finished core-coil assembly. (The inspecting Officer during the course of stage inspection shall seal these core-coil assemblies for purpose of identification of the core coil assembly. The manufacturing programme shall not be interrupted in case purchaser's representative does not reach within seven days of the date of intimation.

32.1 ROUTINE TESTS :

Each completed transformer shall be subjected to following routine tests as per IS:2026 Part.I & III (latest amendment). No extra charges for any of the tests shall be paid. No deviation shall be acceptable. If the supplier desires, he may not fix radiators on transformers(other than the one which is to be type tested) during routine testing. However in that case, radiator manufacturer's test certificate shall be furnished for reference of inspecting officer with undertaking that supplier shall be responsible for proper alignment/fixing of radiator on transformer at site.

a) Measurement of resistance of each winding. b) Measurement of turns ratio between HV-LV windings at each tap. c) Checking of polarity and phase relation-ships for each winding. d) Measurement of no load loss and no load current . e) Positive phase sequence impedance/short circuit impedance between HV-LV windings on minimum ,maximum and normal taps. f) Separate source voltage withstand test. g) Test certificate along with invoice of original manufacture of transformer oil as per IS:335 (latest amended) and to meet the requirement of EHV grade oil shall be furnished and provided to Nigam’s representative during inspection & shall be attached with Inspection Report. However, EHV Grade Transformer Oil shall be subject to BDV test. h) Induced over voltage withstand test. i) Measurement of neutral unbalance current. j) Regulation at rated load at unity, 0.90 and 0.80 lagging power factor. k) Load losses measured at rated frequency by applying voltage sufficient to produce the rated relevant current in one winding with the other winding short circuited. l) Measurement of insulation resistance. m) The total losses shall comprise of the No Load Losses, load losses at rated output duly converted at 75 degree C average winding temperature and shall also be indicated in the test report. Load losses shall be that corresponding to rated load on HV & LV winding. n) Routine dielectric tests as per IS:2026 (Part.I & III). Sticker/ Poly-carbonate seals will be provided on locking chamber of Top filter wheel valve & Bottom drain/sampling wheel valve by Inspecting Officers and details of seals will be mentioned in their inspection report.

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33.0 TYPE TEST CERTIFICATE WITH TENDER :

The detailed legible test certificates for the similar transformers manufactured in the recent past for all the type tests mentioned in the IS:2026 (amended up to date) shall be furnished.

33.1 The firm (s) having authenticated type tests certificates viz. (a) Impulse test with chopped wave test, (b) Thermal and dynamic ability to withstand short circuit test and (c) Temperature Rise Test, got conducted from a Govt. approved/ Govt. Recognized/ NABL Accredited laboratory/ ILAC i.e. International laboratory Accreditation Corporation (in case of foreign laboratory) of the offered rating/ type and design (having same losses as specified by them under GTP), not older than Five years as on date of opening of the tender from the date of conducting type tests shall be considered as meeting the type test criteria and such firm(s) shall not be insisted for arranging fresh type tests. The type test certificate by in house laboratory of bidding firms, even if it is Govt. approved/ Govt. Recognized/ NABL Accredited / ILAC Accredited laboratory shall not be accepted, in case of their own bid. This will not apply if bidding firm is Govt. Company / Public Sector Undertaking. The bidder should furnish documentary evidence in support of laboratory whose type test certificates have been furnished, that the said laboratory is a Govt. approved/ Govt. Recognized/ NABL Accredited laboratory/ ILAC Accredited.

The above Type test shall be carried out by the firm at the Testing house as specified above. Type test carried out by above testing house at firm’s works will not be considered.


After erection at site all transformer(s) shall be subjected to the following tests:

i) Insulation resistance test. ii) Ratio and polarity test. iii) Dielectric test on oil.

In case the equipment is not found as per the requirements of the purchase order, all expenses incurred during site testing will be to the tenderer's account and the material shall be replaced by him at site, free of cost.

35.0 FURTHER TESTS :

The purchaser reserves the right of having other reasonable tests carried out at his own expenses either before dispatch or at site to ensure that the transformer complies with the requirements of this specification.

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36.1 TEST REPORTS :

After all tests have been completed, seven certified copies of each test report shall be furnished. Each report shall supply the following information:- i) Complete identification data including serial number of the transformer. ii) Method of application, where applied duration and interpretation of results for

each tests. iii) Temperature data corrected to 75 degree C including ambient temperature.

37.0 FREQUENCY AND SYSTEM VOLTAGE :

The transformer shall be suitable for continuous operation with a frequency variation of plus minus 3% from normal of 50 cycles per second without exceeding the specified temperature rise. The highest system rated voltage shall be 145 KV. However the flux density requirements shall be as per clause 15.8.

38.0 DRAWINGS :

38.1 The drawings, calculation and the technical literature list below shall be

submitted. i) General outline drawings showing front, side elevations and plan views of

the transformer and all accessories and external features with detailed dimensions, net and shipping weight, crane lift for untanking and for erection/ removal of bushing, size of lifting and pulling eyes, HV & LV terminal clearances, live terminal to ground clearances, quantity of insulating oil etc.

ii) Assembly drawings of HV and LV bushing.

iii) Wiring diagrams and drawings showing temperature indicator/ recorder

circuits alarm circuit.

iv) Drawing showing typical sectional views of the winding with details of insulation, cooling circuit method of coil bracing and core construction along with flux density & current density calculations.

Core assembly drawing showing complete constructional details and flux density calculations.

v) Detailed drawings showing loading for the design of foundations for

transformers.

vi) Drawings showing position of variable fittings.

vii) Drawings showing construction and mounting details of marshalling boxes.

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viii) Drawing showing loadings and centre of gravity of transformer.

ix) Drawings giving details of name plate, terminal marking and connection diagrams.

x) Drawings of bimetallic terminal connectors with test certificates within 15

days of unless otherwise specified of order.

Thermal/dynamic calculations to provide transformers capability to withstand short circuit under worst conditions.

38.2 Each drawing returned by the purchaser will be stamped (a) " Generally

Approved" or (b) " Generally approved subject to observation". In case of (a), no further resubmission of drawings shall be required for purchaser's approval. In case of (b), the contractor shall correct his original drawings to conform to the comments made by the purchaser and resubmit in the same manner as stated above within two weeks after the receipt of the marked up print by him.

38.3 Each drawing shall be identified by a drawings number

38.4 Checking and approval of the drawings by the purchaser is for the benefit of

the supplier and shall not relieve the supplier of full responsibility for ensuring correct interpretation of design drawings and specifications or for completeness and accuracy of the shop drawings and relevant specifications.

38.5 The supplier shall report and incorporate only after purchaser's approval, all

deviations, concessions, omissions changes etc. occurring through the manufacturing assembly and testing phases and submit a complete set of drawings in reproducible forms within 30 days of the date of the equipment is considered to be placed in satisfactory operating condition.

38.6 drawings shall be in English language and dimensions in metric system.

39.0 PERFORMANCE GUARANTEE :

Performance guarantee of transformer shall be for the period of 36 (Thirty Six) months from the date of receipt in stores of purchaser of such transformer complete in all respect. The period during which transformer remained defective/ failed will not be accounted in this performance guarantee period. The period of defective will be reckoned from the date of first intimation to date of delivery after repair.

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40.1 REPAIR GUARANTEE :

The transformer got damaged/failed during the guarantee period due to manufacturing defects or poor workmanship shall be repaired by the supplier within 60 days period from the date of information to the supplier without any liability on the purchaser. The failed Power Transformers shall be mandatorily lifted by the firm from site/ store wherever same is lying failed/ defective.

The GP failed transformer after due repair & inspection by the purchaser, will be routed through Nigam’s in-house Testing Laboratory (CTL) and deliver to the store where CTL exists. Mandatory Testing as mentioned at Clause No. 42.0 shall be carried out and transformer will be accepted on the basis of CTL results. In case Excess No Load /Load losses found than Guaranteed losses, penalty will be levied as per provision of clause 42.0. The difference in penalty on account of excess No Load/Full load losses observed at CTL at the time of original supply and ‘GP failed’ repaired supply will be recovered.

The repaired transformer shall bear a repair warrantee for further 12 months after repair or unexpired period of 36 months from the date of supply whichever is later.

The firm shall provide non-detachable metallic plate with engraved following details of the repaired transformers for the purpose of identification:-

1) Date of first failure 2) Date of expiry of GP after 1st repair under G.P. 3) Date of second/third failure 4) Date of expiry of GP after 2nd /3rd re-repair under G.P.

The above details shall also be punched/embossed on the cover of the transformer. On every re-repair of transformer the date of repair and date of expiry of guarantee period shall have to engraved on rating plate by the contractor. The original name plate of transformer will be retained on the repaired transformers.

41.1 CLEANING AND PAINTING:

i) Before painting or filling with oil, the external surfaces of transformer tank

and structural steel work shall be completely cleaned and made free from rust, scale and grease by applying shot blasting or sand blasting. Cavities on castings shall be filled by metal depositions.

ii) The interior of transformer tank, other oil filled chambers and internal

structural steel work shall be cleaned of all the scales and rust by application of standard approved methods. Thereafter these surfaces shall be painted with hot-oil resistant varnish or paint.

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iii) Except for nuts, bolts and washers which may have to be removed for maintenance purposes all external surfaces shall receive minimum of four coats of paint. The total paint thickness shall be in the range of 52 to 60 microns.

iv) The 1st and 2nd coats of painting shall be of primer and shall be applied

immediately after cleaning. The 3rd coat shall be of an oil and weather resisting quality of a shade or color easily distinguishable from the primary coats and shall be applied after the primary coats have been touched up where necessary. The final coats shall be of glossy oil finish and weather resisting non-fading paint of shade No.632 (Admiral grey) of IS 5 or relevant International Standard Primer paint shall be ready mix Zinc Chromates as per IS 104 or relevant International Standard Intermediate and final coat of paint shall be as per IS:2932 or relevant International Standard.

iii) Metal parts not accessible for painting shall be made of corrosion-resistant material.

iv) Marshalling box shall also be painted with Admiral grey as per shade-632 of IS-5

v) Dry Film Thickness:- a) To the maximum extent practicable, the coats shall be applied as a continuous

film of uniform thickness & free of pores. Overspray, skips, runs, sags & drips should be avoided. The different coats may or may not be of the same colour.

b) Each coat of paint shall be allowed to harden before the next is applied as per manufacturer’s recommendation.

c) Particular attention must be paid to full film thickness at the edges. d) Except for nuts, bolts and washers which may have to be removed for

maintenance purposes, all external surfaces shall receive minimum of four coats of paint. The total paint thickness shall be in the range of 52 to 60 microns.

viii) Test for painted surface:-

a) The panted surface shall be tested for paint thickness. b) The painted surface shall pass the cross hatch adhesion test and impact test as

acceptance tests and salt spray test and hardness test as type test as per the relevant ASTM standards.

c) Supplier shall guarantee the painting performance requirement for a period of not less than 5 years.

42.0 MANDATORY TESTING/VERIFICATION AT STORES:-

The supplier shall route the power transformers through specified lab headquarter for testing and checking of No Load, Load Loss, Magnetizing Current, Percentage Impedance & Fitting & Accessories. Every transformer shall be tested for measurement of losses, Magnetizing Current & Percentage Impedance before delivery of the transformer at the respective store/ site destination. The verification of fitting & accessories of each Transformer shall also be carried out at Stores. The inspecting officer shall issue a provisional Form-9 after satisfactory inspection.

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However, the No Load, Load Loss, Magnetizing Current & Percentage Impedance measured and verification of fitting & accessories at CTL shall be final.

i) Each & Every Transformer shall route through CTL Testing. In CTL, Transformers will be subjected to the following tests:-

a) No Load Losses at 100% & 110% of rated voltage and Magnetizing current will be measured at both voltages.

b) Load losses by Resistance Calculation method. c) Percentage Impedance. d) Verification of fittings & accessories. e) Measurement of tank thickness.

XEn (CTL) shall provide 2 Nos. Poly-carbonate Seals on diagonally opposite side of Transformer after successful testing in CTL as a token of proof that Transformers have been tested at CTL.

(a) No Load Losses:

10% tolerance is allowable. Penalty shall be leviable @ Rs.386.00 per watt for losses exceeding 3000 watts and upto 3300 watts.

(b) Load Losses:

3% tolerance is allowable. Penalty @ Rs.178.00 per watt on losses exceeding 16000 watts and upto 16480 watts.

The transformers having measured No Load Losses/ Load Losses beyond the above permissible limit shall be stand rejected.

(c) Magnetizing Current & Percentage Impedance:

The transformer selected for No Load and Load Losses shall also be subjected to magnetizing current and percentage impedance test and in case found beyond the limit mentioned in specification, the lot shall stand rejected. The tolerance will be as ± 10 % for Normal Tap and ± 15 % for any other Taps for percentage impedance.

(d) The following makes of fittings & accessories shall be verified jointly by the concerned

ACOS (consignee) & XEn (CTL) at the time of CTL testing of Power Transformers:-

a. Buchholz Relay b. WTI & OTI. c. MOG d. Radiator Valve.

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e. Filter valve & Drain valve. f. Off Circuit Tap Changer.

(e) Measurement of Transformer tank thickness shall be done as follows:-

1. Top Cover At 2 places to be measured & average is to be

taken.2. Bottom cover -do-3. Side walls On all four sides (average is to be taken)

The nominal value of sheet thickness shall be considered as mentioned in the above specification.

The following rolling tolerance shall be allowed as per IS:1852 with latest

amendments and no penalty shall be charged on such measured thickness till tolerance limit of IS:-

Tolerance on Thickness (in mm)

Thickness of Sheet Over 5.0mm upto and including 8.0 mm

Over 8.0mm upto and including 10.0 mm

Tolerance in mm +/- 0.35 +/- 0.40

If the observed values of thickness are within or upto 5% less after allowing rolling tolerance as per above, the Transformer may be accepted with levy of penalty after imposing double the penalty of the approximate amount saved by using thin sheet (e.g. if the observed value of thickness are say 5% less after accounting for rolling tolerance and transformer tank weight is 120 Kg. (say), the penalty imposed will be 5/100x120x80 (considering present price of sheet steel is Rs.40/- per Kg. approx.&80=2x40)= Rs.480/-.

Highest percentage variation on negative side shall be taken for accounting the penalty.

If the tank thickness is found beyond 5% of tolerance limit after allowing rolling tolerance, the transformer will be rejected.

(ii) No Load and Load Losses:

The No Load & Load Losses for various ratings of transformers shall be as under (without tolerance):

Rating No Load Losses Load Losses in Watts in Watts------ -------------- -----------

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3.15 MVA 3000 16000 43.1 INSTALLATION & COMMISSIONING

Mainly following activities are required to be carried out before commissioning of Power

Transformers:-

a) Assembling of Power Transformer accessories.

b) Testing activities in presence of XEn (P&EA/AEn (P&EA) such as

(i) Ratio Test (ii) Megger Value (iii) Magnetic balance. (iv) Oil BDV (v) Earth Resistance (vi) Buchholz Relay checking. (vii) WTI/OTI/MOLG (oil level) checking. (viii) Checking of points of leakage of oil from Transformer body/ Radiator/Valve. (ix) Setting of Relays in Panel & Sealing by Protection Wing.

Installation & Commissioning will be carried out in presence of firm’s representative for which concerned AEn (O&M) will intimate to firm and AEn (P&EA)/ XEn(P&EA) by FAX/Telegram/Telephone.

IMPORTANT NOTES :

1. The Tolerance in weight and Dimension of the transformer shall not be

more than plus/minus five percent subject to maintenance of all specified external/ internal electrical clearance. However, there shall be no negative tolerance in tank dimensions, radiator tube lengths, conservator dimensions, and core cross section area. Phase-Phase electrical clearance on 11kV side shall not be less than 280mm with bi-metallic connectors in position.

2. Make of each accessories/components shall be clearly and invariably indicated

in the GTP/bill of material.

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Schedule-V

( To be filled by the Bidder)

Schedule of Guaranteed Technical Particulars for supply of 3.15 MVA Power Transformers

Sr. No.

Particulars Unit 3.15 MVA

1

Manufacturer's Name

a) Postal Add.

b) Works Add.

2 Type , Make & Country of origin

3.A Rated Voltage

a

Voltage between phases on HV side at No LOAD

KV

b

Voltage between phases on LV side at No LOAD

KV

3.B Rated Current

a Rated HV Current Amp.

b Rated LV current Amp.

4

Continuous Max. rating (CMR) under peak ambient air temp. 50deg C with temperature rise as per item 7

KVA

5 a Over load for time of one hour Min.

b 20%overload duration Min.

c 10%overload duration Min.

6 Method of connection

a HV winding

519

b LV winding

7 Vector group reference

8

i

Max. temp. rise obtained by the transformer when run at the max. continuous rating at a peak ambient temp. of 50 degC

a of winding by resistance deg C

b of oil by thermometer deg C

ii

The hottest spot temp.on an annual weighted average ambient temp.of 35 deg. C

deg C

9 Type of cooling

10 Indoor/outdoor installation

11 Range of voltage variation

12 % Variation of steps & No. of steps

/positions

13 Is volts/turn constant regardless of

tap position?

14 Magnetising current in Amp. &P.F.

at rated voltage &frequency

15

Maximum Guaranteed No Load Loss at rated current, rated frequency &rated voltage

KW

16

a

Maximum Guarnteed Load Loss at rated current,rated voltage & rated freq at a ref. temperature of 75 deg. C(AT NORMAL TAP)

KW

b

Maximum Guarnteed Load Loss at current voltage & rated freq at temperature of 75 deg. C(AT MIN. TAP)

KW

c

Max. Total guarnteed loss at rated current, rated voltage& rated freq, at 75 deg. C(At Normal Tap)

KW

520

d

Max. Total guaranteed loss at current voltage& rated freq, at 75 deg. C(At min. tap for heat run test only)

KW

17

a

Resistance of HV winding per phase at 75 deg. C(App. at normal tap)

Ohm

b

Resistance of LV winding per phase at 75 deg. C

Ohm

18 Efficiency at 75 deg.C

a Unity Power Factor :-

i 100% Load %

ii 75% Load %

iii 50% Load %

iv 25%Load %

b

Maximum efficiency and corresponding % load at which Occurs

%

c 0.8 power Factor

i 100% Load %

ii 75% Load %

iii 50% Load %

iv 25%Load %

19 Reactance drop at rated current

and rated freq. %

20 Impedance drop on full load at 75

deg. C

a At Normal tap %

b At Maximum tap %

c At Minimum tap %

21

Duration Of thermal Short Circuit with reference to impedance voltage

Sec.

521

22 Regulation on full load

a

At unity power & temperature of 75 deg.

%

b

At 0.8 power factor and temperature of 75 deg.

%

23 Impulse strength on 1.2/50 ms in

KV (peak)

i of HV winding KVP

ii of LV winding KVP

24 Power frequency withstand voltage

of

i HV winding KVrms

ii LV winding KVrms

25 Minimum clearance to earth

a of primary winding

i in oil mm

ii out of oil mm

b of secondary winding

i in oil mm

ii out of oil mm

c Width oil duct between

i Core & LV mm

ii LV & HV mm

iii out of oil mm

26 Whether oil temp. indicator with

alarm contacts provided

27

Whether two winding temp. indicator with alarm contacts provided

28 Make,Type &Size of oil

temperature indicator

522

29 Make,Type of magnetic oil level

indicator

30 Make,Type & Size of prismatic oil

level gauge

31 Make,Type &Size of gas operated

relay (Buchloz relay)

32 Ratio & type of CT used for W.T.

indicator

a H.V. Ratio

b L.V. Ratio

33 Make of Winding Temperature

Indicator

34 Make of Radiator valve

35 Make of filter valve & Drain valve

36 Type of resistance used for W.T.

Indicator

37 No. of breaters provided & type

thereof

38 Type of dehydrating agent used for

breathing & quantity

39 Outline dimensions

i overall height mm

ii overall Length mm

iii overall Breadth mm

40 Tank Dimensions

i Height mm

ii Length mm

iii Breadth mm

41 Weight in Kg. Of

a Transformer Core Kg.

b Copper Kg.

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c

Transformer Core coils and insulations

Kg.

d Tank & Fittings Kg.

e Oil Kg.

f Transformer tank only Kg.

g Transformer complete with oil Kg.

42 Oil :

A Quantity required for first filling

a Total Ltrs.

b In Radiators Ltrs.

c In Conservator Ltrs.

B

Class &specification to which it conforms

C Make,Type &Brief description

43 Particulars of Tap Changing

Device/tap changer

a Make, Type & Brief description

b

Is an indication arrangement fitted to show the voltage which the circuit tap in circuit gives off

c Can it be locked in position?

d

Position of tap changing wheel of the transformer

e

% variation of OFF LOAD tap changing switch

f Number of steps/positions

44 Accessories and list of fittings with

each transformer

45 i Minimum electrical clearance between phases

a H V mm

b L V mm

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ii

Min. clearance between phase and earth(in air)

a H V mm

b L V mm

46

State whether the transformer comply fully with this specification and its requirement.

47

Whether make, rating, Sr. No. & TN No. punched at four side of Transformer Tank

48

Whether Radiator valve have OPEN/ CLOSE Indication embossed/ casted as well as Painted on both sides of main body of Valve.

Additional Technical Guaranteed Particulars

Sr. No.

Particulars Unit

1 Whether painting at site is required

& provided for.

2

Maximum out of balance force in windings on short circuit with external reactance zero

MT

3

i

Magnetising current & power factor at 110% rated voltage & rated frequency in Amps.

Amp

ii Neutral Unbalanced current Amp

4 No load loss at 110% of rated

voltage & rated frequency kw

5 a Max. flux density at normal voltage and frequency

Lines/ cm Sq.

b

Max. flux density at 110% of normal voltage and frequency

Lines/ cm Sq.

c

Time capability of the transformer to withstand 110% of normal voltage & frequency

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6 WINDING DETAILS

a Max. current density in winding

I

H V Winding (all parts including tapped winding min. tap)

Amps/ sq.mm

ii LV winding

Amps/ sq.mm

b No. of HV coils/phase

c No. of LV coils/phase

d No. of turns/coil (HV)

e No. of turns/coil (LV)

f Weight of HV coil (3) kg

g Weight of LV coil (3) kg

h Voltage per coil (HV) kv

i Voltage per coil (LV) kv

j Inside dia of HV coil mm

k outside dia of HV coil mm

l Inside dia of LV coil mm

m outside dia of LV coil mm

n Axil length of coil mm

7 Type of Transformer shell or core

8 Type of Winding

a H V

b L V

9 Type of axial Coil supports

10 Type of radial Coil supports

11 Type of insulation used

a Core Bolts

b Core Washers

c Core laminations

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12 End clearance from top of HT coil to Yokes

mm

13 Cooling arrangements

a No. of radiators bank

b Size of radiator mm

c No. of fins Nos.

d Total Cooling surface

i Tank surface Sq.mtr.

ii Radiators surface Sq.mtr.

iii Size of radiators fins (Length,Width etc.)

mm

e i

Vertical distance between transformers core & live parts of trfs.

ii Horizontal distance between Radiators.

14 Material used for gasket

15 Fittings & parts to be detached for transport

16 Material & size of relief Outlet diaphram

17 Type of tank

18 Thickness of mild steel plate used in the constructions of tank

a Side walls mm

b Top cover mm

c Bottom plate mm


a H V Conductor

b L V Conductor

c L V to core

d L V to H V

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e Tappings

f Tapping connections

20 Section of copper used

a For H V winding Sq.mm

b For L V winding Sq.mm

21 Type terminal arrangement

22 Grade of core Laminations used

23 Make & Type of bushing

a H V

b L V

c Neutral

d

Creepage distance between HV & LV

mm

24 Reference No. & voltage class to

which the bushing conform

a H V KV

b L V KV

c Neutral KV

Name of Firm

Signature of Bidder

Designation & Seal

Date

528

TECHNICAL SPECIFICATION FOR PURCHASE OF 5.0 & 8.0 MVA 33/11 KV POWER TRANSFORMERS

1.0 SCOPE :

This specification covers the design, manufacture, stage inspection and testing at the manufacturer's works before dispatch, supply and delivery at the destination in area of Jaipur discom of 33/11KV Power Transformer having ratings of 5.0 & 8.0 MVA.


Max. ambient air temperature. 50 degree C.Max. daily average ambient temp. 45 degree C.Max. yearly weighted ambient temp. 35 degree C.Min. ambient air temp. (-) 5 degree C.Max. humidity. 100%Average number of thunder storm days per annum.

40

Average annual rain fall. 15 cm to 100 cm.No. of months during which tropical monsoon conditions prevail.


Maximum wind pressure 195 Kg./Sq.MAltitude above MSL Varies from 61 meters to

815 metersAverage number of rainy days per annum.

120 days.

3.0 GENERAL REQUIREMENTS :

The intention of the specification is to provide information for the design of the above mentioned 33/11 KV power transformers to be fully suitable in every respect for the functions designated. It is required that the supplier in accepting the contract agrees to furnish all apparatus, appliance and material whether specifically mentioned or not, but which may be found necessary to complete, perfect, or test any of the herein specified units in compliance with the requirements implied in this specification without extra charges.

3. 1 All terminal screws, studs, nuts and bolts shall be in accordance with the

Indian Standards. 3.2 All electrical and mechanical equipments shall be designed and

manufactured so that no damage will result from transportation, installation and operation of the equipment under the climatic conditions to which it will be subjected.

529

3.3 All materials used shall conform to this specification and appropriate standards and shall be new in all respects.

3.4 Consideration may be given to alternatives which the supplier considers advisable

by reason of his own manufacturing requirements and experiences, provided descriptive matter is submitted and the recommended device or arrangement equal to, or superior to that required by the accompanying specification and if the purchaser is convinced of the quality and/or superiority of the equipment.

4.0 STANDARDS :

The power transformers, their accessories and fittings, transformer oil, etc. shall conform to the latest edition of the following standards (as amended upto date) except where specified otherwise in this specification :

IS:5/1961: Colour for ready mixed paints IS 2026 (Part 1): 2011 GENERAL (Second Revision); IS 2026(Part2):2010 Temperature Rise (First Revision); IS 2026 (Part 3): 2009 Insulation Levels, Dielectric Tests and External clearance in Air (Third Revision); IS :2026 (Part IV)-1977 Reaffirmed 2011 – Terminal Markings, Tapping and Connections; IS 2026 (Part 5):2011 – Ability to withstand short circuit. IS:6600/1978:Guide for loading of oil immersed Transformers IS:335/1983:New insulation oils for Transformers IS:3347(PART-III/Sec-1 & 2): Dimensions of Porcelain parts

& Metal parts for Transformer bushing (17.5 KV).

IS:3637: Gas & Oil operated Relay. IS:3639/1966: Fittings & accessories for Transformers IS:1866/1978: Code of practice for maintenance & supervision

of insulating oil in service. IS:9335: Specifications for insulating craft paper. IS:1576: Specifications for solid insulating press Boards for

electrical purposes. IS:104: Ready mixed paint, brushing zinc chromate, painting IS:649: Testing of steel sheets and strips for magnetic circuits. IS:2362: Determination of water content in oil for porcelain

bushing transformers. IS:4257: Dimensions for clamping arrangements for bushings. IS:6160: Rectangular conductor for electrical machines. IS:10028: Selection, Installation and maintenance of transformers IS:3401 : Silica gel IS:5561: Terminal Connector IS:2070: Method of impulse voltage testing

4.1 Equipment meeting the requirements of any other authoritative standards which ensures a quality equal to or better than that as per the standards mentioned above, shall also be acceptable. Where the equipment conforms to any other standards, salient points of difference between the standards adopted and the specified standards shall be clearly brought out in the tender.

530

5.0 TROPICAL TREATMENT :

Under the climatic conditions prevalent at the site, the equipment supplied under the specification will be subjected to operation under the ambient temperature specified under clause 2.0 and very high relative humidity. All equipments shall, therefore be suitably designed and tested for normal life and satisfactory operation under the extreme climatic conditions prevalent at the site and shall be dust and vermin proof. All parts and surfaces which are subjected to corrosion shall be made of such material and shall be provided with such protective finishes as would protect the equipment installed from any injurious effects of excessive humidity. All electrical auxiliary equipment shall be specifically tested for tropical conditions and the materials for this treatment shall be as per modern engineering practices.

6.0 ELECTRICITY RULES :

All work shall be carried out in accordance with the latest edition of the Indian Electricity Act-1910, Electricity supply Act-1948, Electricity Act-2003, Electricity rules-2005 and rules formed there under and as amended from time to time.

7.0 TYPE AND RATING :

7.1 The transformers shall be of 3 phase, copper wound, core type construction,

oil immersed and shall be suitable for outdoor service as step down transformers ( At times however these may be required to work under reversal of power also).

7.2 These transformers may be required to run in parallel with existing

transformers of the similar capacity. The technical particulars of transformers required are as under:

i) Maximum continuous rating at reference : 5.0 MVA & 8.0 MVA

ambient temperature specified under clause 3.02

ii) Frequency : 50 Hz

iii) No. of phases : 3 phase

iv) Rated primary Voltage on principal : 33 KV tapping

v) Rated secondary Voltage : 11 KV

vi) Winding connections:

a) HV side : Delta b) LV side : Star c) Vector group reference : Dyn11

vii) Type of cooling : ONAN

531

viii) Percentage impedance at normal voltage & 75 deg.C average winding temp.(on 20 MVA base) between HV-LV at.-

Tap No. 5.0 MVA 8.0 MVA Tolerance a) Normal tapping(Tap-3)

7.00 % 8.00% ± 10%


6.65% 7.60% ± 15%

c) At min.tapping (-10%)

7.70% 8.80% ± 15%

However, firm already having valid type tests with the following impedance value on the date of opening of Techno-commercial Bid then same shall also be acceptable:-

Tap No. 5.0 8.0 Tolerance

a) Normal tapping(Tap-3)

7.15% 8.35% ± 10%


6.79% 8.30% ± 15%

c) At min. tapping (-10%):

7.86% 8.75% ± 15%

ix) Off circuit tap changer: Having 6 equal steps (7 position) of 2.5% of each, to have voltage variation of +5% to -10% on HV side.

x) Neutral unbalance : Not exceeding 2.0%

current xi) Type of terminal : Vertical take off type

suitable for ACSR "Panther" conductor on both sides.

xii) Max.current density in all parts: 5.0 MVA 8.0 MVA of HV and LV windings including 3Amp./Sq.mm 2.8Amp./Sq.mm tapped winding. for minimum tap in HV & LV.

xiii) Bushing metal part for HV & LV : M -20 size (copper/

bushing. brass)

8.0 EFFICIENCY :

The percentage loading for the max. efficiency shall be clearly stated in the tender at unity power factor as well as 0.8 p.f. lagging.

9.0 INSULATION :

9.1 The dielectric strength of the winding, given insulation and the bushings

shall conform to the values given in IS:2026(Part.3)/2009 (or its

532

latest amendment) for

533

highest system voltage of 36KV,12KV and shall be suitable for the following impulse test \ power frequency test voltages.

SYSTEM VOL. H.SYSTEM VOL. IMPULSE TEST VOL. PF TEST VOL. ---------- ------------- ---------------- ------------

33 KV 36 KV 170 KVp 70 KV 11 KV 12 KV 75 KVp 28 KV

H.V. & L.V. Winding of Transformer shall have uniform insulation. 10.1 TEMPERATURE RISE :

Each transformer shall be capable of operating continuously at their normal rating without exceeding temperature rise limits as specified below :

---------------------------------------------------------------

Type of Temp.rise External cooling. cooling

medium (Air) ---------------------------------------------------------------

2 measured by thermometer method)

---------------------------------------------------------------

The reference temperature conditions for which the transformers shall be designed are as under (as per clause 3.02).

a) Maximum ambient temperature. : 50 degree C. b) Maximum daily average ambient temp. : 45 degree C. c) Maximum yearly weighted : 35 degree C.

ambient temperature.

The hottest spot temperature shall not exceed 98 degree C when calculated over an annual weighted average ambient temperature of 35 degree C when transformer is loaded to its rated capacity. The transformer shall be capable of being over loaded to 150% of its rating in accordance of IS 6600-1972.

i) Bushing and its terminal connectors shall have minimum continuous current rating corresponding to 120% rated current of transformer at lowest tap.

11.0 PARALLEL OPERATION :

The transformers covered by this specification are to run in parallel with transformers which are either already installed or are being installed (for same rating) and as such the characteristics of the transformers covered in this specification for the sub station will be identical so as to enable these transformers to run in parallel.

12.0. IMPEDANCES :

1. Winding( Temp.rise ONAN 50 degree C. When the oil measured by resistance circulation ismethod) natural non

directed . Oil ( Temp.rise As above. 45 degree C. -

534

Suppliers shall indicate the guaranteed impedances and tolerances taking into account the limits at minimum and maximum tap position so as to fulfill requirements of clause 11.0.

13.0 GUARANTEED LOSSES:

13.1. The Losses shall not exceed the values given below:

-----------------------------------------------------

Rating No load losses Load losses at in KW 75 deg.C.in KW

(At normal tap condition)

-----------------------------------------------------

5.0 MVA 4 KW 23 KW8.0 MVA 5.5 KW 40 KW-----------------------------------------------------

The above mentioned losses are maximum permissible and there shall not be any plus tolerance above this limit. Design calculations of No-load and load losses along with complete Technical details and factors assumed will be enclosed Along with the GTP in tender documents.

13.2 In case during testing, the actual loss (es) are found within guaranteed figure, the

transformers shall be accepted without any advantage to contractor for lower losses. 13.3 Measurements of losses shall form part of type test/ routine test.

13.4 The losses on transformer supplied shall also be guaranteed at the time of pre-

commissioning test and transformers having losses exceeding figures mentioned in clause 3.14.1 above shall stand rejected.

13.5 The supplier shall supply two copies of the Routine test certificate to consignee

with each transformer on receipt of despatch instructions. 13.6 The supplier shall provide along with the tender the design details of core

assembly showing the construction details, core diameter, net/ gross sectional area of the core assembly etc. The information must also be given in respect of volts per turn at principal tap for normal voltage. The loss curves for type/grade of steel laminations being used for the core shall also be provided along with the tender.

14.0 COOLING :

14.1 Each transformer shall be provided with ONAN type cooling as specified under the

schedule of requirements.

14.2 The ONAN cooling of the transformers shall be by natural circulation of air while the circulation of oil shall be effected by natural convection, the maximum oil

535

flow being assured by a method whereby the return flow of cooled oil is made to enter the tank at a level coinciding with the bottom of the hot columns of oil thus avoiding centre heads of cold oil at the bottom of the tank. Out flow shall be arranged to coincide as nearly as possible with the hot oil level at the top of the tank so that the total available difference will be fully employed in circulating the oil round the shortest possible paths.

14.3 The windings of the transformers shall be designed to deliver continuously rated

MVA corresponding to ONAN cooling.

Radiators shall be provided for cooling purpose. These shall be directly mounted on the tank on both sides in a balanced manner & not on one side only.

14.4 The Radiator to be used should be of PSR type for all three type of rating.

14.5 For heat dissipation calculation for tank surface at 45 Degree, 500 watt per Sq. meter

will be considered and for Radiator, heat dissipation will be worked out as per manufacturing chart provided by manufacturer, firm will enclose the chart.

14.6 The cooling arrangement shall consist of detachable radiators which may be directly

mounted on the transformers. Connections between the radiators and tank shall be made with flanges provided with gaskets and an indicating sheet valve provided at both connection ends, which can be fastened in either open or closed position.

14.7 The radiators shall be so arranged that these can be detached from the tank or bank

without disturbing the oil in transformer. These shall be designed to withstand the vacuum and pressure specified for the tank.

14.8 Radiators shall be so designed as to be for cleaning & painting to prevent

accumulation of water on the outer surface to completely drain oil from the tank or bank and to ensure against formation of gas pockets when the tank is being filled. All connections between the radiators and tank or bank and between the bank & tank shall be provided with flanges when the particular item is detached. Each radiator shall have a lifting eye, an oil drain and vent at top.

14.9 The height of the radiator should not be above the transformer tank & All the

Radiator shall be so arranged that they can be directly be connected to tank without any bend.

14.10 The indication regarding state of opening/ closing of radiator valve should be clearly identified through paint-marking.

15.0 TRANSFORMER CORE :

15.1 The core shall be built up with thin lamination of high grade, non ageing, low loss, high permeability, cold rolled, grain oriented silicon steel specially suitable for transformer core. The particulars of laminated steel to be

536

employed shall be supplied with the tenders along with DC magnetization, B- H and iron loss curves.

15.2 After being sheared the laminations shall be treated to remove all burrs and shall

be re-annealed to remove all residual stresses. At least one side of each lamination shall be coated with a double baked enamel insulation coating which will not deteriorate due to pressure and the action of hot oil. The nature of insulation shall be specified in the tender.

15.3 Every care shall be exercised in the selection, treatment and handling of core

steel to ensure that as far as practicable, the laminations are flat and the finally assembled core is free from distortion.

15.4 The design of the magnetic circuit shall be such as to avoid discharges, development

of short circuit paths within itself or to the earthed clamping structure and the production of flux components at right angles to the plane of the laminations which may cause local heating.

15.5 The core shall be rigidly clamped to ensure adequate mechanical strength and to

prevent vibration during operation. The core/clamping bolts shall not pass through Core/Yoke and clamping structure shall be so constructed that eddy currents will be minimum.

15.6 The core shall be provided with lugs suitable for lifting the complete core and coil

assembly of the transformer. The core and the coil shall be so fixed in tank that shifting will not occur when the transformer is moved or during a short circuit.

15.7 The core shall be of high grade cold rolled gain oriented annealed steel laminations, having low loss and good grain properties, coated with hot oil proof insulation, bolted together to the frames firmly to prevent vibration or noise. All core clamping bolts shall be effectively insulated. The complete design of core must ensure the permanency of the core losses with continuous working of the transformers. The value of the flux density allowed in the designs and grade of laminations used shall be clearly stated in the offer, along with the curves. The transformer core shall be constructed out of the prime class of materials. The transformer core shall be of prime quality CRGO steel. The bidder shall import the core directly or shall purchase directly from the imported and he will furnish the following documents at the time of stage inspection of the transformer:-

a) Invoice of supplier. b) Mill’s test certificate. c) Packing list. d) Bill of landing e) Bill of entry certificate by custom.

Description of material, electrical analysis, physical inspection, certificate for surface defects, thickness and width of the material.

15.8 FLUX DENSITY :

537

The flux density in any part of the core built from cold rolled grain oriented steel shall not exceed 16000 (in case of 5.0 MVA) & 15000 (in case of 8.0 MVA) lines per sq. cm. at any tap position necessary to maintain No Load terminal voltage of 11KV on LV side as required. The transformer shall also be suitably designed to withstand upto 10% upward primary voltage variation at normal tap continuously without saturation and excessive heating of the core and windings. Due regard shall also be given to limiting the flux density based on the characteristics of the material used.

The tenderer shall furnish magnetization curve for material indicating max working flux density without saturation. The tenderer shall indicate max. flux density in core/yoke at rated voltage to establish that the max. flux density at 10% over voltage (with reference to nominal voltage) does not cause core saturation.

The design calculations in support of flux density shall be furnished by the tenderer along with drawing of cores steps and calculations of effective cross sectional area of the core. For finding out no load current, average values of all the three limbs and phases should be taken into consideration.

16.0 WINDING :

16.1 The windings shall be so designed that all coil assemblies of identical

voltage ratings shall be inter changeable and field repairs to the windings can be made readily, without special equipment. The coils shall be supported between adjacent sections by insulating spacers and bracers. Bracings and other insulation used in the assembly of the windings shall be arranged to ensure a free circulation of the oil and to reduce hot spots in the windings. The windings shall be designed to reduce to a minimum the out of balance forces in the transformer at all ratios.

16.2 The insulation of the coils shall be suitable to develop the full electrical strength

of the windings. All materials used in the insulation and assembly of the windings shall be insoluble, non catalytic, and chemically inactive in the hot transformer oil, and shall not soften or otherwise be adversely effected under the operating conditions.

16.3 All threaded connections shall be provided with locking facilities. All leads from

the windings to the terminal board and bushings shall be rigidly supported to prevent injury from vibration. Guide tubes shall be used where practicable.

16.4 The windings shall be clamped securely in place so that they will not be

displaced or deformed during short circuits. The assembled core and windings shall be vacuum dried and suitably impregnated. The electrolytic copper conductor used in the coil structure shall be best suited to the requirements and all permanent current carrying joints in the windings and the leads shall be welded or braced except compression type which may be used for terminal connections. Bolted connection may be used at the bushings and at terminal

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board with suitable locking device. The drying out procedure of the core coil assembly shall be indicated in the tender.

17.0 FAULT WITHSTANDING CAPACITY OF WINDINGS :

All the windings shall be suitably designed to withstand short time rating for not less than 2 seconds by feeding the fault level of 1000 MVA on HV side, 750 MVA on 11 KV side respectively from both ends and considering the severe most form of system faults that can arise in service. Tenderer(s) should furnish the detailed calculations for thermal as well as dynamic ability of windings to withstand short circuits as prescribed above, failing which their quotations are likely to be ignored. The max. temp. attained for short time rating shall not exceed 250 degree C.

18.0 INSULATING OIL :

18.1 The oil for first filling shall be supplied with each transformer. The oil shall be

EHV grade-I and shall comply IS:335/1993 latest version & amendment. 18.2 Particular attention shall be paid to deliver the oil for topping up free from

moisture having uniform quality through out in the non-returnable new steel drums.

18.3 The quantity of oil for first filling of each transformer shall be stated in the

tender . Quantity of oil required for filling of conservator and radiators shall be stated in the guaranteed technical particulars.

18.4 The transformer oil purchased from M/s. Savita Chemical, M/s. Apar, M/s.

Raj Lubrichem, M/s. Raj Petroleum, M/s Tashkant, M/s Sharavathy, M/s Rinki/M/s Madras Petrochem and M/s. Lubrichem, M/s Columbia shall only be supplied. Invoice and test certificates of manufacturer of transformer oil shall have to be furnished as and when desired by the Nigam.

19.0 TANK :

19.1 The transformer tank and cover shall be fabricated from good commercial grade low

carbon steel suitable for welding and of adequate plate thickness. The tank and the cover shall be of welded construction. All seams shall be welded and where practicable they shall be double welded. The transformer tank shall have sufficient strength to withstand without permanent distortion. The punching on all 4 sides of Power Transformer tank with letter size of 10x5mm will be carried out. The details to be punched are as under:-

i) IPDS/ TN No.

ii) Serial No.

iii) Make

vi) Rating.

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The thickness of tank sheet shall be as under:-

S.No. Dimensions of 5.0 MVA 8.0 MVA

i. Top Cover 8mm 10mm

ii. Side Cover 6mm 8mm

iii. Bottom Cover 8mm 10mm

19.2 At least one manhole/inspection cover with a welded flange and a bolted cover shall be provided on the tank cover. The manhole shall be of a sufficient size to afford easy access to the lower ends of the bushings, terminals etc.

19.3 All bolted connections to the tank shall be fitted with suitable oil tight gaskets

which shall give satisfactory service under the operating conditions. Special attention shall be given to the methods of making the hot oil tight joints between the tank and the cover as also between the cover and the bushing and all other outlets to ensure that the joints can be remade satisfactorily and with ease , with the help of semi-skilled labour. Where compressible gaskets are used, steps shall be provided to prevent over compression. Suitable guides shall be provided for positioning the various parts during assembly or dismantling.

19.4 Lifting eyes or lugs shall be provided on all the parts of the transformers

requiring independent handling during assembly or dismantling. In addition the transformer tank shall be provided with lifting lugs and bolts properly secured to the sides of the tank, for lifting the transformer either by cranes or by jacks.

19.4.1 The design of the tank, the lifting lugs and bosses shall be such that the

complete transformer assembly filled with oil can be lifted with the use of these lugs without any damage or distortions. The tank shall be provided with two suitable copper alloy, lugs for the purpose of groundings.

19.4.2 The main body of the tank shall have sufficient strength to withstand and without

permanent distortion i) A vacuum of 760mm of mercury. ii) Continuous internal gas pressure of 0.7 atmosphere above atmosphere

pressure with oil at operating level i.e. the transformer tank should be able to withstand 100% vacuum and also one atmosphere pressure above atmosphere internal pressure.

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19.4.3 The tank cover shall be belled to the tank and the transformer design shall be such that at the tank will not split between the lowest and upper cooler connections.

19.4.4 Each tank shall be provided with the following

a) Lifting lugs suitable for lifting the transformer complete with oil

accessories lifted with oil by cranes. b) A minimum of four jacking lugs, in accessible position to enable the

transformers complete with oil to be raised or lowered using hydraulic or screw jacks.

The minimum height of jacking lugs above base shall be

i) Transformer above 10 tonnes weight : 500 mm ii) Transformer upto and including 10 tons weight: 300 mm.

Horizontal plates with 50mm dia drew holes drilled therein shall be fitted adjacent to each corner of the rectangular tank at more than 750 mm from the base to permit haulage in any direction. On the rounded tanks drew holes shall be located on the diagonals of the rectangular formed by the overall boundaries of the tank.

19.5 Each tank cover shall be adequate strength and shall not distort when lifted.

Inspection opening shall be provided to give easy access to lower ends of bushings, terminals etc. for changing ratio or winding connection or testing to each connections. These shall be of adequate to size not less than 450mm x 350mm

19.6 Suitable guides shall be provided for positioning the various parts during assembly

or dismantling. Adequate space should be provided between the cores and winding and the bottom of tank for collection of any sediment.

19.6.1 The base channel for transformer shall be 250 x 6 x 82 mm.

19.6.2 Prismatic oil level gauge indicator on transformer tank shall be provided to

indicate level of oil in Transformer tank at a suitable place on LV bushing side.

19.0 UNDER CARRIAGE :

20.1 The transformer tank shall be supported on a structural steel base. 20.2 Pulling eyes shall be provided to facilitate moving the transformer and they

shall be suitably braced in a vertical direction so that bending does not occur when the pull has a vertical component.

21.0 OFF LOAD TAP CHANGER MECHANISM:

21.1 The off circuit tap changer shall be of high quality and robust in construction.

It shall be located at a convenient position so that it can be operated from

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ground level by a standing operator. The handle of OCTC shall be provided with a locking arrangement, thus enabling the OCTC to be locked in position. Arrangement for indicating of tap position shall also be provided. It shall be suitable for local manual operations. The tap changer shall be capable of permitting parallel operation with other transformer of the same type. When one unit is in parallel with another of same type as mentioned in clause No.11 under normal condition, the tap changer shall not become out of step. The OFF Load Tap Changer should be of following makes only:-

iv) M/s Paragone Associates, Thane. v) M/s Alwaye, Bangalore.

21.2 The OCTC shall be capable of carrying rated MVA on all taps. The breaking

capacity of the OCTC shall be compatible with the highest system voltage and current based on maximum over loading permissible under IS:6600 -1972 (150% of rated value). The voltage rating for each step shall be 2.5% on HV side. However, each step of OCTC shall withstand voltage not less than 115% of rated step voltage. The rated through current of OCTC at this voltage will not be less than 150% of rated current of HV winding at lowest tap.

22.0 CONSERVATOR:

22.1. Oil preserving equipment shall be conventional conservator tank type. The

minimum oil level in the conservator tank shall not be below the level of the bushing flanges.

22.2 Oil conservator tank shall be located well clear of the bare connection of the

transformer terminals. The conservator tank shall have adequate capacity between highest and lowest permissible levels to meet the requirement of expansion of the total cold oil volume in the transformer and cooling equipment from min. amb. temperature to highest oil temp. as per desired.

22.3 The total volume of the conservator shall be min. 10% of the total quantity of oil

in transformer. The inside diameter of the pipe connecting the conservator to the main tank shall be min.50mm and it should be projected into the conservator in such a way that its end is projected 30mm above the bottom so as to create sump for collection of impurities. The min. oil level should be above the sump level.

22.4 A conservator complete with sump and drain valve shall be provided in such a

position as not to obstruct the electrical connections to the transformer, having a capacity between highest and lowest visible levels to meet the requirement of expansion of the total cold oil volume in the transformer and cooling equipment from the minimum ambient temperature shall be with 0 Deg. C to 90 Deg.C. The minimum indicated oil level shall be with the feed pipe from the tank covered with not less than 15mm depth of oil and the indicated range of oil level shall be minimum to maximum.

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22.5 The oil connection from transformer tank to the conservator vessel shall be arrange at a rising angle of 3 Deg. to 9 Deg. to the horizontal up to gas and oil actuated relay and shall consist of 50mm inside diameter pipe.

22.6 Each conservator vessel shall be fitted with a breather in which silica gel is the

dehydrating agent and designed so that

a) The passage of air is through silica gel. b) The external atmosphere is continuously in contact with silica gel. c) The moisture absorption indicated by a change in colour of the tinted

crystals can be observed from distance. d) Breathers shall be mounted at approx. 1400 mm above ground level.

23.0 TEMPERATURE INDICATING DEVICE:

23.1 The tripping contacts of above temperature indicators shall be adjustable to

close between 60 Deg.C and 120 Deg.C and alarm, contacts to close between 50 Deg. C & 10 Deg.C and both shall reopen when the temperature has fallen by above 10 Deg.C.

24.0 MARSHALLING BOX OR KIOSK

24.1 A sheet vermin proof well ventilated and weather proof marshalling box of the

suitable construction shall be provided for the transformer ancillary apparatus. The box shall have domed or sloping roofs and the interior and exterior painting shall be in accordance with specification.

24.2 The marshalling box, wherever provided shall accommodate the following equipments alternatively weather proof instruments can be mounted outdoor.

f) Temperature indicators. g) Terminal boards and gland plates for incoming and out going cables.

24.3 All the above equipments except (b) shall be mounted on panels and back of

panel wiring shall be used for inter connection. 24.4 The temperature indicators shall be so mounted that the dials are not more

than 1600 mm from ground level and the door (s) are of adequate size. 24.5 To prevent internal condition an approved type of metal clad heater shall be

provided controlled by a suitable switch. Ventilation louvers shall be provided. 24.6 All incoming cables shall enter the kiosk from the bottom and the gland plate

shall be not less than 450mm from the base of box. The gland plate and associated compartment shall be sealed in suitable manner to prevent the ingress of moisture from the cable trench.

25.0 DIAGRAM AND RATING PLATE

Each transformer shall be provided with a non-detachable brass or stainless steel plate mentioning complete information as given in clause 7 of latest version of IS

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2026 (Part 1): 2011 and diagram of winding connection and taps shall be provided. The property of respective Discom and specification no. shall be engraved on the plate Guaranteed values of No-Load loss and Load loss at 75 Deg.C without and plus tolerance along with measured values as well as temperature rise figures should also be inscribed on the diagram and rating plates.

26.0 BUSHINGS :

26.1 All main winding and neutral leads for 33/11 KV transformers shall be

brought out through outdoor type bushings. The electrical characteristics of bushing shall be in accordance with IEC-137 as well as IS-3347/8603 and IS- 2099. The bushing shall be rated for highest voltage and current rating of the respective windings. The current ratings of bushing shall be at least 150% of the rated current at minimum tap to permit overloading.

26.2. The bushings shall have high factor of safety against leakage to ground and

shall be so located as to provide adequate electrical clearances between bushings and between the bushings and ground parts. The spacing between the bushings shall be adequate to utilize full flashover strength preventing flashover between the phases or between phase and ground parts under all conditions of operation. The creepage distance of bushing shall not be less than 25 mm per KV.

26.3 All bushings shall be equipped with suitable solder less terminals of approved

type. The type and size shall be specified in the tender. All external current carrying contact surfaces shall be placed adequately.

26.4. Bushings of identical voltage ratings shall be interchangeable .

26.5 Special adjustable arcing horns shall be provided with HV & LV bushings. Each

bushings shall be so coordinated with the transformer insulation that all flashover occur outside the tank.

26.6 All porcelain used in bushings shall be of the wet process homogeneous

impervious to moisture and free from cavities or other flaws and throughout vitrified and smoothly glazed. The glazing shall be of the uniform colour and free from blisters, burns and other defects. All bushings shall have puncture strength greater than the dry flashover voltage.

26.7 The crepage distance of 33 KV bushing surfaces shall not be less than 900 mm & for 11 KV shall not be less than 300 mm.

26.8 Terminal conductor of HV & LV shall be vertical take off type and suitable for ACSR PANTHER.

27.0 (A) SUPPRESSION OF HARMONICS:

The transformer shall be designed with particular attention to the suppression of harmonics voltages especially in the third & fifth harmonics so as to eliminate wave form distortion and any possibility of high frequency disturbances.

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27.0 (B) MARKING

All transformers shall have the marking in paint on the body for identification as per Indian Standards or as instructed by purchaser.

28.0 CENTRE OF GRAVITY.

The centre of gravity of the assembled transformer shall be low and as near the vertical centre line as possible. The transformer shall be stable with or without oil. If the centre of gravity is eccentric relative to track either with or without oil its location shall be shown in the outline drawing in all the views showing their position of Transformer track also.

29.0 FITTINGS AND ACCESSORIES :

29.1. Each transformer shall be provided with the following fitting and accessories in

accordance as specified in IS:2026:

(i) Oil Temperature Indicator (OTI) The transformer shall be provided with one 150 mm dial type, oil Temperature Indicator for indicating top oil temperature. The indicator shall have adjustable electrically independent ungrounded alarm and trip contacts with Micro Switches and maximum reading pointer. The temperature-sensing element shall be suitably located in a pocket on the top of the transformer and shall be connected to the oil temperature indicator by means of capillary tubing protected with a metal sheath. The accuracy class of the OTI shall be +/- 1%


(ii) Winding Temperature Indicator:-

The Transformer shall also be provided with a device for indicating the temperature of winding (HV and LV separately). It shall comprise the following:-

a) Temperature sensing element suitably located on the top cover of the transformer. b) 150 mm dial, local indicating instrument with maximum reading pointer, mounted in

the cooler control cabinet and two adjustable electrically independent ungrounded contacts with Micro switches (beside that required for control of cooling equipment). The tripping contacts shall be adjustable to close between 60 Deg. C and 120 Deg.C and alarm contacts to close between 50 Deg. C and 100 Deg. C and both shall reopen when the temperature has fallen by a desired amount between 5 Deg. C and 50 Deg.C. All contacts shall be adjustable on a scale. They shall be accessible on removal of the cover and it shall be possible to check the operation of the contacts and associated equipments. Connections from the contacts shall be brought down to the terminal Block, placed inside the marshalling box. The accuracy class of the WTI shall be +/- 1%.

c) Calibration device:

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ii) One filter valve located at the top of the tank on the LV side. The opening of this valve shall be baffled to prevent aeration of oil.

iv) One drain cum filter valve with sampling valve for main tank with plug or core plate of suitable size with locking arrangement located near the bottom of the tank on the HV side of the transformer but diagonally opposite to LV side.

The above filter/drain valves shall be located on non-bushing side of the Transformer. It should be placed on bottom side of tap changer and on top of the diagonally opposite side.

v) Air release device. It shall be of adequate capacity and shall be provided to release the trapped air during/after filling of the oil.

vi) Explosion vent (Pressure release device).

vii) One No. double float Buchholz relay shall be provided with alarm and tripping contacts to detect accumulation of gas and sudden changes of oil pressure, complete with shut-off valves on either side and flange coupling to permit easy removal without lowering oil level in the main tank, a bleed valve for gas venting and a test valve. The Buchholz relay shall be of best indigenous make having ISI certification. Buchholz relay must be made of cast iron/ aluminum.

viii) Detachable radiators complete with shut off valves as necessary for cooling

as per clause 14.0.

ix) An oil conservator having detachable end plates, with following provisions.

a) Magnetic type oil level gauge:- The conservator shall be fitted with one magnetic oil level gauge with nitro-phyll float having:

i) Dial with minimum, maximum & normal (at 30 Deg.C) Oil level marking and a pointer. iii) Low Oil level alarm contacts of 0.5 Amp. 110V/ 30V DC.

b) One oil filling hole with plug and drain valve on the conservator. c) one prismatic oil level gauge having painted/embossed marking as min.,

normal, and max. oil level.

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d) Silica gel breather with Oil seal and Dehydrating agent. x) Eye bolts and lugs on all parts for ease of handling.

xi) Two grounding terminals as per clause No.19.5.

xii) Rating, Diagram and terminal marking plates :

Rating, diagram and terminal marking plates of stainless steel or brass for transformers and other accessories giving details as per IS:2026 shall be provided. Value of full wave (1.2/50 micro second) impulse level, short circuit current. its duration, weights of all important items, Impedances, loss values at normal/extreme taps and Postal address. Performance guarantee clause 39.0 shall also be indicated.

xiii) All transformers shall have the marking in paint on the body for identification

as per Indian Standard or as instructed by purchaser. Further, the following should be embossed at the top of the tank cover.

a) Sr. No. of the transformer. b) IPDS/TN No. c) Name of the firm. d) Month and year of manufacture.

xiv) Bimetallic terminal connectors suitable for "ACSR Panther" for HV and LV

bushing and earthing clamps should be as per IS:5561.

xv) Suitable weather proof cubicles (Marshalling box) for housing the local control equipment for fans, terminal blocks, for current transformer secondary and for mounting winding temperature indicators and oil temperature indicator as (i) and (ii) above.

xvi) HV and LV bushings with adjustable arcing horns 3 Nos. and 4 Nos.

respectively. xvii) Triple pole type off load tap changer as per cl.no.21.0 xviii) Skids : xix) Hauling Eyes : Hauling eyes shall be provided on all the four sides of the

transformer base. xx) Jacking Pads :Four, sturdy jacking pads shall be provided for lifting complete

transformer. Lifting height and safe capacity of jacks shall be specified in Bid. xxi) Lifting Lugs : Two sets of forged or tested mild steel plate lifting lugs, one

set for top cover, core and coil assembly and other set of complete transformer shall be provided. Lifting lugs shall be of adequate strength and size for attaching steel rope slings. Should lugs for lifting complete transformer be located on the base, sling guides shall be provided on cover.

xxii) Inspection Covers :One inspection covers of sufficient size for access to the

interior of the tank shall be provided on the cover. The inspection covers shall be provided with suitable lifting arrangements.

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All type of valves shall be of gun metal except radiator shut off valves which may be of cast iron/steel. All valves shall be provided either with blind companion flanges or with pipe plugs for protection.

The makes of fitting & accessories will be as under:-

S.No. Fitting & Accessories Makes

1 Buchholz relay Atvus, Sukrat, Suvidha.

2 Winding Temperature Indicator/ Oil Temperature Indicator

OTI/WTI Model integrated RTD Schemefor ROTI/RWTI with remote indicator ofM/s Preci Measure Control Pvt. Ltd./Thermal System, Belltek

3 Magnetic type oil level gauge Atvus, Sukrat, Instrument & Control

4 Radiator Valve Hari Industries, Atvus, Vinayak, Vimal Techno, Petsun, Kailash

5 Filter valve & Drain valve Zolote, L&T, G.G., Leader, Uttam, PunjabMetal (ELMS mark), Leader, Hari Ind., Newman Ind.

Radiator valves shall have clear & distinct OPEN/CLOSE indication embossed/ casted as well as painted on the both sides of main body of valve. Radiator valve should have zero leakage with cap remove.

The new makes of fitting & accessories may be accepted with the approval of SE(TW),JVVNL, Jaipur on the basis of ISI approval certificate/ tests reports from any NABL accredited Lab./Govt. Lab./ performance report from utilities.

29.2 LOCKING ARRANGEMENT

To curb the theft of oil from power transformers, the following parts are either required to be blocked/ plugged or provided under provisions of locking:-

S. No.

Transformer Part Mode of blocking

1. Conservator drain plug/ valve

Cap shall be provided as per drawing `b’.

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2. Both oil filtration valves Cap shall be provided as per drawing à’.

3. Transformer Oil drain valve.

Cap shall be provided as per drawing à’.

4. Radiator drain plug (Bottom)

Cap shall be provided as per drawing `c’.

5. Radiator Air release plug (Top)

Locking on top for which provision is to be provided by firm and informed to SE(TW) for approval.

6. Conservator filling hole. To provide locking arrangement for which provision is to be provided by firm and informed to SE(TW) for approval.

7. Air release plug on top cover.

To provide wire mesh cap arrangement so that only air can be released.

Drawing is enclosed.

30.0 FACTORY ASSEMBLY AND TESTS : 30.1 The transformer shall be completely assembled and tested at the Factory. It shall be

at the option of the purchaser to send a representative(s) for carrying out stage inspection and various tests during actual manufacture and assembly of transformer(s) so as to satisfy regarding the quality of product and material being used.

30.2 All Type and Routine tests as per specification are to be conducted and no deviation

in respect of conducting these tests will be acceptable. No extra charges for these tests will be paid. Test charges shall be part of cost of the equipment. Even if charges for such test are indicated elsewhere in the tender, it will be presumed that these tests will be conducted free of cost. If purchaser selects to send a representative, all tests shall be carried out in his presence.

31.1 STAGE INSPECTION :

Before carrying out the stage inspection the following documents shall be given to Inspecting Officer(s) for verification:

a) Invoice of supplier b) Mill's test certificate c) Packing list d) Bill of landing e) Bill of entry certificate by custom f) description of material, electrical analysis, physical inspection, certificate for

surface defects, thickness and width of the material.

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The purchaser's representative may carry out stage inspection of the transformers during manufacturing/ assembling stage. The purchaser shall have absolute right to reject the raw material/ component/ sub assemblies or complete equipment not found to be conforming to the requirement of the specification or being of poor quality/ workmanship. The stage inspection will particularly include following tests/ check besides the general routine tests to be conducted during manufacturing stages as per manufacturer's standard practice.

a) Physical inspection/checking of winding insulating material, core material and

other accessories/fitting of transformer. b) Measurement of core area, cross sectional area of winding(s), number of turns in

each winding. c) Verification of HV and LV Coils, conductor size, I.D., O.D., Axial Length, Weight,

Insulation covering etc. d) Measurement of thickness of tank plates (Bottom and sides) and to conduct

pressure & vacuum tests as per CBIP manual for transformer tests to ensure the adequate strength of tank plates.

e) Sample testing of core material for checking specific loss, magnetization characteristics

(i.e. B.H. Curve plot) and thickness. f) Visual and dimensional check during assembly stage of core.

g) high voltage test(2KV,50Hz for one minute) between all core-bolts if provided and

agreed to frame bars/fish plates etc. and ferro-magnetic steel of core. h) Check on completed core for measurement iron loss and check for any hot spot by

exciting the core so as to induced the design values flux density. i) Check for proper provisions of spacers and bracings to arrest the movement of core

and winding assembly inside the tank. j) Check complete transformer against approved outline drawing, provision for all

fittings, finish oil level etc.

The purchaser at his option may collect the sample of the following raw material/ component for independent testing:

a) CRGO

Laminations One specimen sheet of 300-500mm length and 50-75mm width (for each lot).

b) HV winding wire 1250 mm length specimen for each type c) LV winding wire 1250 mm length specimen for each type d) Transformer oil 2 samples of 5 litres each.

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To facilitate stage inspection, the supplier should intimate complete schedule of manufacturing programme of the transformers at least 15 days in advance to the SE (MM) of respective Discom. At least 50% of the transformers shall be offered in the shape of finished core-coil assembly. (The inspecting Officer during the course of stage inspection shall seal these core-coil assemblies for purpose of identification of the core coil assembly. The manufacturing programme shall not be interrupted in case purchaser's representative does not reach within seven days of the date of intimation.

32.1 ROUTINE TESTS :

Each completed transformer shall be subjected to following routine tests as per IS:2026 Part.I & III (latest amendment). No extra charges for any of the tests shall be paid. No deviation shall be acceptable. If the supplier desires, he may not fix radiators on transformers(other than the one which is to be type tested) during routine testing. However in that case, radiator manufacturer's test certificate shall be furnished for reference of inspecting officer with undertaking that supplier shall be responsible for proper alignment/fixing of radiator on transformer at site.

a) Measurement of resistance of each winding. b) Measurement of turns ratio between HV-LV windings at each tap. c) Checking of polarity and phase relation-ships for

each winding. d) Measurement of no load loss and no load current . e) Positive phase sequence impedance/short circuit impedance between HV-LV windings on minimum ,maximum and normal taps. f) Separate source voltage withstand test. g) Test certificate along with invoice of original manufacture of transformer oil as per IS:335 (latest amended) and to meet the requirement of EHV grade oil shall be furnished and provided to Nigam’s representative during inspection & shall be attached with Inspection Report. However, EHV Grade Transformer Oil shall be subject to BDV test. h) Induced over voltage withstand test. i) Measurement of neutral unbalance current. j) Regulation at rated load at unity, 0.90 and 0.80 lagging power factor. k) Load losses measured at rated frequency by applying voltage sufficient to produce the rated relevant current in one winding with the other winding short circuited. l) Measurement of insulation resistance. m) The total losses shall comprise of the No Load Losses, load losses at rated output duly converted at 75 degree C average winding temperature and shall also be indicated in the test report. Load losses shall be that corresponding to rated load on HV & LV winding. n) Routine dielectric tests as per IS:2026 (Part.I & III). Sticker/ Poly-carbonate seals will be provided on locking chamber of Top filter wheel valve & Bottom drain/sampling wheel valve by Inspecting Officers and details of seals will be mentioned in their inspection report.

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33.0 TYPE TEST CERTIFICATE WITH TENDER :

The detailed legible test certificates for the similar transformers manufactured in the recent past for all the type tests mentioned in the IS:2026 (amended upto date) shall be furnished.

33.1 The firm (s) having authenticated type tests certificates viz. (a) Impulse test with chopped wave test, (b) Thermal and dynamic ability to withstand short circuit test and (c) Temperature Rise Test, got conducted from a Govt. approved/ Govt. Recognized/ NABL Accredited laboratory/ ILAC i.e. International laboratory Accreditation Corporation (in case of foreign laboratory) of the offered rating/ type and design (having same losses as specified by them under GTP), not older than Five years as on date of opening of the tender from the date of conducting type tests shall be considered as meeting the type test criteria and such firm(s) shall not be insisted for arranging fresh type tests. The type test certificate by in house laboratory of bidding firms, even if it is Govt. approved/ Govt. Recognized/ NABL Accredited / ILAC Accredited laboratory shall not be accepted, in case of their own bid. This will not apply if bidding firm is Govt. Company / Public Sector Undertaking. The bidder should furnish documentary evidence in support of laboratory whose type test certificates have been furnished, that the said laboratory is a Govt. approved/ Govt. Recognized/ NABL Accredited laboratory/ ILAC Accredited.

The above Type test shall be carried out by the firm at the Testing house as specified above. Type test carried out by above testing house at firm’s works will not be considered.


After erection at site all transformer(s) shall be subjected to the following tests:

i) Insulation resistance test. ii) Ratio and polarity test. iii) Dielectric test on oil.

In case the equipment is not found as per the requirements of the purchase order, all expenses incurred during site testing will be to the tenderer's account and the material shall be replaced by him at site, free of cost.

35.0 FURTHER TESTS :

The purchaser reserves the right of having other reasonable tests carried out at his own expenses either before dispatch or at site to ensure that the transformer complies with the requirements of this specification.

36.1 TEST REPORTS :

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After all tests have been completed, seven certified copies of each test report shall be furnished. Each report shall supply the following information:- i) Complete identification data including serial number of the transformer. ii) Method of application, where applied duration and interpretation of results for

each tests. iii) Temperature data corrected to 75 degree C including ambient temperature.

37.0 FREQUENCY AND SYSTEM VOLTAGE :

The transformer shall be suitable for continuous operation with a frequency variation of plus minus 3% from normal of 50 cycles per second without exceeding the specified temperature rise. The highest system rated voltage shall be 145 KV. However the flux density requirements shall be as per clause 15.8.

38.0 DRAWINGS :

38.1 The drawings, calculation and the technical literature list below shall be

submitted by each tenderer with the tender. i) General outline drawings showing front, side elevations and plan views of the

transformer and all accessories and external features with detailed dimensions, net and shipping weight, crane lift for untanking and for erection/ removal of bushing, size of lifting and pulling eyes, HV & LV terminal clearances, live terminal to ground clearances, quantity of insulating oil etc.

ii) Assembly drawings of HV and LV bushing.

iii) Wiring diagrams and drawings showing temperature indicator/ recorder

circuits alarm circuit.

iv) Drawing showing typical sectional views of the winding with details of insulation, cooling circuit method of coil bracing and core construction along with flux density & current density calculations.

Core assembly drawing showing complete constructional details and flux density calculations.

v) Detailed drawings showing loading for the design of foundations for

transformers.

vi) Drawings showing position of variable fittings.

vii) Drawings showing construction and mounting details of marshalling boxes.

viii) Drawing showing loadings and centre of gravity of transformer.

ix) Drawings giving details of name plate, terminal marking and connection diagrams.

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x) Drawings of bimetallic terminal connectors with test certificates within 15 days of unless otherwise specified of order.

Thermal/dynamic calculations to provide transformers capability to withstand short circuit under worst conditions.

38.2 Each drawing returned by the purchaser will be stamped (a) " Generally

Approved" or (b) " Generally approved subject to observation". In case of (a), no further resubmission of drawings shall be required for purchaser's approval. In case of (b), the contractor shall correct his original drawings to conform to the comments made by the purchaser and resubmit in the same manner as stated above within two weeks after the receipt of the marked up print by him.

38.4 Should the supplier wish to resubmit a revision or change for approval such

resubmission shall be made in three prints. The contractor shall also supply prints of each approved revised drawing(s) within 15 days of receiving the approved revised drawing(s).

38.5 Any shop work done prior to approval of the drawing shall be at the

supplier's risk. The supplier shall make all such changes in the design as are considered necessary to make the equipment conform to the provisions and intent of this specification without any additional cost to the purchaser.

38.6 Each drawing shall be identified by a drawings number and each subsequent

resubmission/ revision or addition to the drawings or procedure. All drawings shall be thoroughly checked for accuracy and completeness and signed or initialed by a responsible officer of the contractor.

38.7 Checking and approval of the drawings by the purchaser is for the benefit of

the supplier and shall not relieve the supplier of full responsibility for ensuring correct interpretation of design drawings and specifications or for completeness and accuracy of the shop drawings and relevant specifications.

38.8 The supplier shall report and incorporate only after purchaser's approval, all

deviations, concessions, omissions changes etc. occurring through the manufacturing assembly and testing phases and submit a complete set of drawings in reproducible forms within 30 days of the date of the equipment is considered to be placed in satisfactory operating condition.

38.9 All drawings shall be in English language and dimensions in metric

system. 39.0 PERFORMANCE GUARANTEE :

Performance guarantee of transformer shall be for the period of 36 (Thirty Six) months from the date of receipt in stores of purchaser of such transformer complete in all respect.

554

The period during which transformer remained defective/ failed will not be accounted in this performance guarantee period. The period of defective will be reckoned from the date of first intimation to date of delivery after repair.

40.0 REPAIR GUARANTEE :

The transformer got damaged/failed during the guarantee period due to manufacturing defects or poor workmanship shall be repaired by the supplier within 60 days period from the date of information to the supplier without any liability on the purchaser. The failed Power Transformers shall be mandatorily lifted by the firm from site/ store wherever same is lying failed/ defective.

The GP failed transformer after due repair & inspection by the purchaser, will be routed through Nigam’s in-house Testing Laboratory (CTL) and deliver to the store where CTL exists. Mandatory Testing as mentioned at Clause No. 3.46 (B) shall be carried out and transformer will be accepted on the basis of CTL results. In case Excess No Load /Load losses found than Guaranteed losses, penalty will be levied as per provision of clause 42 (B). The difference in penalty on account of excess No Load/Full load losses observed at CTL at the time of original supply and ‘GP failed’ repaired supply will be recovered.

The repaired transformer shall bear a repair warrantee for further 12 months after repair or unexpired period of 36 months from the date of supply whichever is later.

The firm shall provide non-detachable metallic plate with engraved following details of the repaired transformers for the purpose of identification:-

5) Date of first failure 6) Date of expiry of GP after 1st repair under G.P. 7) Date of second/third failure 8) Date of expiry of GP after 2nd /3rd re-repair under G.P.

The above details shall also be punched/embossed on the cover of the transformer. On every re-repair of transformer the date of repair and date of expiry of guarantee period shall have to engraved on rating plate by the contractor. The original name plate of transformer will be retained on the repaired transformers.

41.1 CLEANING AND PAINTING:

i) Before painting or filling with oil, the external surfaces of transformer tank

and structural steel work shall be completely cleaned and made free from rust, scale and grease by applying shot blasting or sand blasting. Cavities on castings shall be filled by metal depositions.

555

ii) The interior of transformer tank, other oil filled chambers and internal structural steel work shall be cleaned of all the scales and rust by application of standard approved methods. Thereafter these surfaces shall be painted with hot-oil resistant varnish or paint.

iii) Except for nuts, bolts and washers which may have to be removed for

maintenance purposes all external surfaces shall receive minimum of four coats of paint. The total paint thickness shall be in the range of 52 to 60 microns.

iv) The 1st and 2nd coats of painting shall be of primer and shall be applied

immediately after cleaning. The 3rd coat shall be of an oil and weather resisting quality of a shade or color easily distinguishable from the primary coats and shall be applied after the primary coats have been touched up where necessary. The final coats shall be of glossy oil finish and weather resisting non-fading paint of shade No.632 (Admiral grey) of IS 5 or relevant International Standard Primer paint shall be ready mix Zinc Chromates as per IS 104 or relevant International Standard Intermediate and final coat of paint shall be as per IS:2932 or relevant International Standard.

vii) Metal parts not accessible for painting shall be made of corrosion-resistant material.

viii) Marshalling box shall also be painted with Admiral grey as per shade-632 of IS-5

ix) Dry Film Thickness:- e) To the maximum extent practicable, the coats shall be applied as a continuous

film of uniform thickness & free of pores. Overspray, skips, runs, sags & drips should be avoided. The different coats may or may not be of the same colour.

f) Each coat of paint shall be allowed to harden before the next is applied as per manufacturer’s recommendation.

g) Particular attention must be paid to full film thickness at the edges. h) Except for nuts, bolts and washers which may have to be removed for

maintenance purposes, all external surfaces shall receive minimum of four coats of paint. The total paint thickness shall be in the range of 52 to 60 microns.

ix) Test for painted surface:-

d) The panted surface shall be tested for paint thickness. e) The painted surface shall pass the cross hatch adhesion test and impact test as

acceptance tests and salt spray test and hardness test as type test as per the relevant ASTM standards.

f) Supplier shall guarantee the painting performance requirement for a period of not less than 5 years.

42.0 MANDATORY TESTING/VERIFICATION AT STORES:-

The supplier shall route the power transformers through specified lab headquarter for testing and checking of No Load, Load Loss, Magnetizing Current, Percentage Impedance & Fitting & Accessories. Every transformer shall be tested for

556

measurement of losses, Magnetizing Current & Percentage Impedance before delivery of the transformer at the respective store/ site destination. The verification of fitting & accessories of each Transformer shall also be carried out at Stores. The inspecting officer shall issue a provisional Form-9 after satisfactory inspection. However, the No Load, Load Loss, Magnetizing Current & Percentage Impedance measured and verification of fitting & accessories at CTL shall be final.

(i) Each & Every Transformer shall route through CTL Testing. In CTL, Transformers will be subjected to the following tests:-

a) No Load Losses at 100% & 110% of rated voltage and Magnetizing current will be measured at both voltages.

b) Load losses by Resistance Calculation method. c) Percentage Impedance. d) Verification of fittings & accessories. e) Measurement of tank thickness.

XEn (CTL) shall provide 2 Nos. Poly-carbonate Seals on diagonally opposite side of Transformer after successful testing in CTL as a token of proof that Transformers have been tested at CTL.

(a) No Load Losses:

5.0 MVA


8.0 MVA


(b) Load Losses:

3% tolerance is allowable. Penalty @ Rs.178.00 per watt on losses exceeding 23000 watts and upto 23690 watts for 5.0 MVA rating & 44000 watts and upto 45320 Watts for 8.0 MVA rating.

The transformers having measured No Load Losses/ Load Losses beyond the above permissible limit shall be stand rejected.

(c) Magnetizing Current & Percentage Impedance:

The transformer selected for No Load and Load Losses shall also be subjected to magnetizing current and percentage impedance test and in case

557

found beyond the limit mentioned in specification, the lot shall stand rejected. The tolerance will be as ± 10 % for Normal Tap and ± 15 % for any other Taps for percentage impedance.

(d) The following makes of fittings & accessories shall be verified jointly by the concerned

ACOS (consignee) & XEn (CTL) at the time of CTL testing of Power Transformers:-

g. Buchholz Relay h. WTI & OTI. i. MOG j. Radiator Valve. k. Filter valve & Drain valve. l. Off Circuit Tap Changer.

(e) Measurement of Transformer tank thickness shall be done as follows:-

1. Top Cover At 2 places to be measured & average is to be

taken. 2. Bottom cover -do-3. Side walls On all four sides (average is to be taken)

The nominal value of sheet thickness shall be considered as mentioned in the above specification.

The following rolling tolerance shall be allowed as per IS:1852 with latest amendments and no penalty shall be charged on such measured thickness till tolerance limit of IS:-

Tolerance on Thickness (in mm)

Thickness of Sheet Over 5.0mm upto and including 8.0 mm

Over 8.0mm upto and including 10.0 mm

Tolerance in mm +/- 0.35 +/- 0.40

If the observed values of thickness are within or upto 5% less after allowing rolling tolerance as per above, the Transformer may be accepted with levy of penalty after imposing double the penalty of the approximate amount saved by using thin sheet (e.g. if the observed value of thickness are say 5% less after accounting for rolling tolerance and transformer tank weight is 120 Kg. (say), the penalty imposed will be 5/100x120x80 (considering present price of sheet steel is Rs.40/- per Kg. approx.&80=2x40)= Rs.480/-.

Highest percentage variation on negative side shall be taken for accounting the penalty.

558

If the tank thickness is found beyond 5% of tolerance limit after allowing rolling tolerance, the transformer will be rejected.

(ii) No Load and Load Losses:

The No Load & Load Losses for various ratings of transformers shall be as under (without tolerance):

Rating No Load Losses Load Losses in Watts in Watts------ -------------- -----------5.0 MVA 4000 23000

9.0 MVA 6100 44000 43.0 INSTALLATION & COMMISSIONING

Mainly following activities are required to be carried out before commissioning of Power

Transformers:-

a) Assembling of Power Transformer accessories.

c) Testing activities in presence of XEn (P&EA/AEn (P&EA) such as

(x) Ratio Test (xi) Megger Value (xii) Magnetic balance. (xiii) Oil BDV (xiv) Earth Resistance (xv) Buchholz Relay checking. (xvi) WTI/OTI/MOLG (oil level) checking. (xvii) Checking of points of leakage of oil from Transformer body/ Radiator/Valve. (xviii) Setting of Relays in Panel & Sealing by Protection Wing.

Installation & Commissioning will be carried out in presence of firm’s representative for which concerned AEn (O&M) will intimate to firm and AEn (P&EA)/ XEn(P&EA) by FAX/Telegram/Telephone.

559

IMPORTANT NOTES :

1. The Tolerance in weight and Dimension of the transformer shall not be more than plus/minus five percent subject to maintenance of all specified external/ internal electrical clearance. However, there shall be no negative tolerance in tank dimensions, radiator tube lengths, conservator dimensions, and core cross section area. Phase-Phase electrical clearance on 11kV side shall not be less than 280mm with bi-metallic connectors in position.

3. Make of each accessories/components shall be clearly and invariably indicated

in the GTP/bill of material.

560

( To be filled by the Bidder)

Schedule of Guaranteed Technical Particulars for supply of 5.0 MVA& 8.0MVA Power Transformers

Sr. No.

Particulars Unit 5.0MVA 8.0MVA

1

Manufacturer's Name

a) Postal Add.

b) Works Add.

2 Type , Make & Country of origin

3.A Rated Voltage

a

Voltage between phases on HV side at No LOAD

KV

b

Voltage between phases on LV side at No LOAD

KV

3.B Rated Current

a Rated HV Current Amp.

b Rated LV current Amp.

4

Continuous Max. rating (CMR) under peak ambient air temp. 50deg C with temperature rise as per item 7

KVA

5 a Over load for time of one hour Min.

b 20%overload duration Min.

c 10%overload duration Min.

6 Method of connection

a HV winding

b LV winding

7 Vector group reference

561

8

i

Max. temp. rise obtained by the transformer when run at the max. continuous rating at a peak ambient temp. of 50 degC

a of winding by resistance deg C

b of oil by thermometer deg C

ii

The hottest spot temp.on an annual weighted average ambient temp.of 35 deg. C

deg C

9 Type of cooling

10 Indoor/outdoor installation

11 Range of voltage variation

12 % Variation of steps & No. of steps

/positions

13 Is volts/turn constant regardless of

tap position?

14 Magnetising current in Amp. &P.F.

at rated voltage &frequency

15

Maximum Guaranteed No Load Loss at rated current, rated frequency &rated voltage

KW

16

a

Maximum Guarnteed Load Loss at rated current,rated voltage & rated freq at a ref. temperature of 75 deg. C(AT NORMAL TAP)

KW

b

Maximum Guarnteed Load Loss at current voltage & rated freq at temperature of 75 deg. C(AT MIN. TAP)

KW

c

Max. Total guarnteed loss at rated current, rated voltage& rated freq, at 75 deg. C(At Normal Tap)

KW

d

Max. Total guarnteed loss at current voltage& rated freq, at 75 deg. C(At min. tap for heat run test only)

KW

562

17

a

Resistance of HV winding per phase at 75 deg. C(App. at normal tap)

Ohm

b

Resistance of LV winding per phase at 75 deg. C

Ohm

18 Efficiency at 75 deg.C

a Unity Power Factor :-

i 100% Load %

ii 75% Load %

iii 50% Load %

iv 25%Load %

b

Maximum efficiency and corresponding % load at which Occurs

%

c 0.8 power Factor

i 100% Load %

ii 75% Load %

iii 50% Load %

iv 25%Load %

19 Reactance drop at rated current

and rated freq. %

20 Impedance drop on full load at 75

deg. C

a At Normal tap %

b At Maximum tap %

c At Minimum tap %

21

Duration Of thermal Short Circuit with reference to impedance voltage

Sec.

22 Regulation on full load

a

At unity power & temperature of 75 deg.

%

563

b

At 0.8 power factor and temperature of 75 deg.

%

23 Impulse strength on 1.2/50 ms in

KV (peak)

i of HV winding KVP

ii of LV winding KVP

24 Power frequency withstand voltage

of

i HV winding KVrms

ii LV winding KVrms

25 Minimum clearance to earth

a of primary winding

i in oil mm

ii out of oil mm

b of secondary winding

i in oil mm

ii out of oil mm

c Width oil duct between

i Core & LV mm

ii LV & HV mm

iii out of oil mm

26 Whether oil temp. indicator with

alarm contacts provided

27

Whether two winding temp. indicator with alarm contacts provided

28 Make,Type &Size of oil

temperature indicator

29 Make,Type of magnetic oil level

indicator

30 Make,Type & Size of prismatic oil

level gauge

564

31 Make,Type &Size of gas operated

relay (Buchloz relay)

32 Ratio & type of CT used for W.T.

indicator

a H.V. Ratio

b L.V. Ratio

33 Make of Winding Temperature

Indicator

34 Make of Radiator valve

35 Make of filter valve & Drain valve

36 Type of resistance used for W.T.

Indicator

37 No. of breaters provided & type

thereof

38 Type of dehydrating agent used for

breathing & quantity

39 Outline dimensions

i overall height mm

ii overall Length mm

iii overall Breadth mm

40 Tank Dimensions

i Height mm

ii Length mm

iii Breadth mm

41 Weight in Kg. Of

a Transformer Core Kg.

b Copper Kg.

c

Transformer Core coils and insulations

Kg.

d Tank & Fittings Kg.

e Oil Kg.

565

f Transformer tank only Kg.

g Transformer complete with oil Kg.

42 Oil :

A Quantity required for first filling

a Total Ltrs.

b In Radiators Ltrs.

c In Conservator Ltrs.

B

Class &specification to which it conforms

C Make,Type &Brief description

43 Particulars of Tap Changing

Device/tap changer

a Make, Type & Brief description

b

Is an indication arrangement fitted to show the voltage which the circuit tap in circuit gives off

c Can it be locked in position?

d

Position of tap changing wheel of the transformer

e

% variation of OFF LOAD tap changing switch

f Number of steps/positions

44 Accessories and list of fittings with

each transformer

45 i Minimum electrical clearance between phases

a H V mm

b L V mm

ii

Min. clearance between phase and earth(in air)

a H V mm

b L V mm

566

46

State whether the transformer comply fully with this specification and its requirement.

47

Whether make, rating, Sr. No. & TN No. punched at four side of Transformer Tank

48

Whether Radiator valve have OPEN/ CLOSE Indication embossed/ casted as well as Painted on both sides of main body of Valve.

Additional Technical Guaranteed Particulars Against TN-2259

Sr. No.

Particulars Unit

1 Whether painting at site is required

& provided for.

2

Maximum out of balance force in windings on short circuit with external reactance zero

MT

3

i

Magnetising current & power factor at 110% rated voltage & rated frequency in Amps.

Amp

ii Neutral Unbalanced current Amp

4 No load loss at 110% of rated

voltage & rated frequency kw

5 a Max. flux density at normal voltage and frequency

Lines/ cm Sq.

b

Max. flux density at 110% of normal voltage and frequency

Lines/ cm Sq.

c

Time capability of the transformer to withstand 110% of normal voltage & frequency

6 WINDING DETAILS

a Max. current density in winding

I

H V Winding (all parts including tapped winding min. tap)

Amps/ sq.mm

567

ii LV winding Amps/ sq.mm

b No. of HV coils/phase

c No. of LV coils/phase

d No. of turns/coil (HV)

e No. of turns/coil (LV)

f Weight of HV coil (3) kg

g Weight of LV coil (3) kg

h Voltage per coil (HV) kv

i Voltage per coil (LV) kv

j Inside dia of HV coil mm

k outside dia of HV coil mm

l Inside dia of LV coil mm

m outside dia of LV coil mm

n Axil length of coil mm

7 Type of Transformer shell or core

8 Type of Winding

a H V

b L V

9 Type of axial Coil supports

10 Type of radial Coil supports


a Core Bolts

b Core Washers

c Core laminations

12 End clearance from top of HT coil to Yokes

mm

13 Cooling arrangements

a No. of radiators bank

568

b Size of radiator mm

c No. of fins Nos.

d Total Cooling surface

i Tank surface Sq.mtr.

ii Radiators surface Sq.mtr.

iii

Size of radiators fins (Length,Width etc.)

mm

e i

Vertical distance between transformers core & live parts of trfs.

ii

Horizontal distance between Radiators.

14 Material used for gasket

15 Fittings & parts to be detached for

transport

16 Material & size of relief Outlet

diaphram

17 Type of tank

18 Thickness of mild steel plate used

in the constructions of tank

a Side walls mm

b Top cover mm

c Bottom plate mm


a H V Conductor

b L V Conductor

c L V to core

d L V to H V

e Tappings

f Tapping connections

20 Section of copper used

569

a For H V winding Sq.mm

b For L V winding Sq.mm

21 Type terminal arrangement

22 Grade of core Laminations used

23 Make & Type of bushing

a H V

b L V

c Neutral

d

Creepage distance between HV & LV

mm

24 Reference No. & voltage class to

which the bushing conform

a H V KV

b L V KV

c Neutral KV

Name of Firm

Signature of Bidder

Designation & Seal

Date

570

TECHNICAL SPECIFICATION FOR SUPPLY OF 11/0.433KV, 25 KVA RATING ALUMINIUM WOUND OUTDOOR TYPE COMPLETELY SELF PROTECTED THREE STAR RATING DISTRIBUTION TRANSFORMERS WITH METER PROTECTION BOX HAVING PROVISION OF SINGLE METER .

1. SCOPE:

This specification covers the design, engineering, manufacture, assembly, inspection and testing at manufacturer’s works before supply of Oil immersed, Oil Natural Air Natural (ONAN) outdoor type Three Star Rating 11KV/433 V, three phase, 50 Hz, double wound core type, outdoor Type, Aluminum Wound Distribution Transformers of 25 KVA ratings, complete with fittings and accessories with metering protection unit on LT side of Distribution Transformers for use in Distribution System.

1.1 The Equipment Offered shall be complete with all parts necessary for their effective and trouble free operation. Such parts will be deemed to be within the scope of the supply irrespective of whether they are specifically indicated in the commercial order or not.

1.1.1 It is not the intent to specify herein complete details of design and construction. The equipment offered shall conform to the relevant standards and be of high quality, sturdy, robust and of good design and workmanship complete in all respects and capable to perform continuous and satisfactory operations in the actual service conditions at site and shall have sufficiently long life in service as per statutory requirements. In actual practice, not withstanding any anomalies, discrepancies, omissions, incompleteness, etc. in these specifications and attached drawings, the design and constructional aspects, including materials and dimensions, will be subject to good engineering practice in conformity with the required quality of the product, and to such tolerances, allowances and requirements for clearances etc. as are necessary by virtue of various stipulation in that respect in the relevant Indian Standards, IEC standards, I.E. Rules, I.E Act and other statutory provisions.

1.2 The Tender / supplier shall bind himself to abide by these considerations to the satisfaction

of the Purchaser and will be required to adjust such details at no extra cost to the purchaser over and above the tendered rates and prices.

1.3 Tolerances on all the dimensions shall be in accordance with provisions made in the relevant Indian/ IEC standards and in these specifications. Otherwise the same will be governed by good engineering practice in conformity with required quality of the product.

571


Unless otherwise modified in the specifications, the Distribution Transformers, including various accessories, shall generally comply with the following Indian Standards / REC Specifications. The standard(s) shall be with latest amendment, if any, from time to time.

Note: Wherever ISS are mentioned, equivalent or better International standards are also acceptable:

Sr. No.

Specification Details about International & internationally recognized standards.

1 IS: 1180 (PART-I) IS:2026

Specifications for outdoor type oil immersed distribution transformers up to and including 2500 KVA, 11 KV Class, with latest amendments.

IEC 76

2 IS:6600/1978 Guide for loading of oil immersed Transformers

IEC 76

3 IS:335/1983 New insulation oils for Transformers BS 148, D-1473, D- 1533 – 1934, IEC PUB 296

4 IS:3347 (Part-I/ Sec. 1 & 2)

Dimension of Porcelain parts & Metal parts forTransformer bushing (1.1 KV).

DIN 42531 to 33

5 IS:3347 (PART-III / Sec-1 & 2)

Dimensions of Porcelain parts & Metal parts for Transformer bushing (17.5 KV).

6 IS:7421 Porcelain Transformer Bushings for low voltage – upto 1 KV.

7 IS:2099/1986 Porcelain Transformer bushing for AC volts above 1000 volts.

8 IS:3639/1966 Fittings & accessories for Transformers

9 IS:1866/1978 Code of practice for maintenance & supervision of insulating oil in service.

10 IS:5484 Specifications for Aluminium wire rods. ASTM B – 233 11 IS:9335 Specifications for insulating kraft paper. IEC 554 12 IS:1576 Specifications for solid insulating press

Boards for electrical purposes. IEC 641

13 IS:616 (Part I) Specification for paper covered Aluminium round conductors

14 IS:6162(Part II) Specification for paper covered Aluminium rectangular conductors

15 IS:104 Ready mixed paint, brushing zinc chromate, painting

16 IS:649 Testing of steel sheets and strips for magnetic circuits.

17 IS:2362 Determination of water content in oil for porcelain bushing transformers.

18 IS: 4257 Dimensions for clamping arrangements for bushings.

572

19 IS 6160 Rectangular conductor for electrical machines.

20 IS:10028 Selection, Installation and maintenance of transformers

21 IS: 3401 Silica gel 22 - REC Specification

No. 2 - REC Specification No. 39/1993 - CEA Specification Chapter 4

Material conforming to other internationally accepted standards, which ensure equal or higher quality than the standards mentioned above would also be acceptable. In case the Bidders who wish to offer material conforming to the other standards, salient points of difference between the standards adopted and the specific standards shall be clearly brought out in relevant schedule. Four copies of such standards with authentic English Translations shall be furnished along with the offer.

3. SERVICE CONDITIONS:

The distribution transformers to be supplied against this specification shall be suitable for satisfactory continuous operation under the following climatic conditions as per IS 2026 (Part- I) latest revision.

i) Peak ambient temperature : 50°C

ii) Minimum Ambient Temperature in shade : -5°C iii) Maximum average ambient temp. in a 24 hours period in shade : 45°C iv) Maximum yearly weighted average ambient temperature : 35°C v) Maximum temperature attainable by an object exposed to sun : 60°C vi) Maximum relative humidity : 100 % vii) Average number of thunder storm days per annum : 40 viii) Average number of rainy days per annum : 120 ix) Average annual rainfall : 15-100 cm x) Number of months of tropical monsoon conditions : 4 Months xi) Maximum wind pressure : 195 Kg/mt² xii) Altitudes : Not exceeding

: 1000 mtrs. The equipment shall be for use in moderately hot and humid tropical climate,

conducive to rust and fungus growth.

4. PRINCIPAL PARAMETERS: The Transformers shall be suitable for outdoor installation with three phase 50 Hz 11

KV system in which the neutral is effectively earthed and should be suitable for outdoor service as step down transformers under fluctuations in supply voltage upto plus 10% to minus (-) 15 % permissible under Indian Electricity Act and rules there under.

The transformer shall confirm to the following specific parameters:

573

i) Continuous rated capacity : 25 KVA

ii) System Voltage ( Max.) : 12 KV

iii) Rated HT voltage : 11 KV

iv) Rated LT voltage : 433 V (P-P) / 250 V (P-N)

(v) Line current HV : 1.31 A

(Vi) Line current LV : 33.33 A

vii) Frequency : 50 Hz

viii) No. pf phases : THREE

ix) Primary connection (HT) : DELTA

x) Secondary connection (LT) : STAR

xi) Vector Group : Dyn-11

xii) Percentage impedance at 75°C : 4.5 %

xiii) Taps (off circuits) : TAPS ARE NOT REQUIRED.

xiv) Type of cooling : ON AN

xv) Fault level of the system : 750 MVA

Primary winding shall be DELTA connected and the secondary winding shall be STAR connected (vector symbol Dyn-11), so as to produce a positive displacement of 30° from the primary to the secondary vectors of the same phase. The neutral of the secondary winding shall be brought out to a separate insulated terminal. The transformers shall be Aluminium Wound.

The transformers shall be designed and constructed to withstand without damage the thermal and dynamic stresses of an external short circuit. The manufacturer / supplier shall furnish all relevant design data and calculations in support of having fulfilled this requirement as stipulated in IS:2026 (Part-I)

574

5. NO LOAD VOLATGE RATIO:

The No load voltage ratio(s) shall be 11000/ 433 Volts. 6. THE LOSSES:

6.1 The bidder shall guarantee individually the no-load loss and load loss without any positive tolerance. The bidder shall also guarantee the total losses (no load +

load losses at 75 0C) at the 50% of rated load and total losses at 100% of rated shall not exceed the maximum total loss values given in Table-9 of IS 1180(Part- 1):2014.

6.2 The maximum allowable losses at rated voltage and rated frequency permitted at 75 0C for 11/0.433 kV transformers can be chosen by the utility as per Table-9 for ratings 5,10, 16, 25kVA as per Energy Efficiency Level-2 specified in IS 1180 (Part-1): 2014 for single phase distribution transformers.

6.2 The above losses are maximum allowable and there would not be any positive tolerance. Bids with higher losses than the above specified values would be treated as non-responsive.

Note:- The Distribution Transformers shall be BIS certified in line with electrical transformers (quality control) order,2015(along with its latest amendments) issued by Department of heavy industries, Ministry of heavy industries & public Enterprises, Govt. of India.

7. TEMPERATURE RISE: The temperature rise over ambient shall not exceed the limits given below:

i) Top oil temperature rise measured by thermometer 35 Deg. C.

ii) Winding temperature rise measured by resistance method 40 Deg. C.

Temperature rise test shall be conducted on Guaranteed losses at a Govt. approved/ a Govt. recognized/ NABL accredited laboratory/ILAC i.e. International Laboratory Accredited Laboratory/ ILAC i.e. International Laboratory Accreditation Cooperation (in case of foreign laboratory)

Temperature rise test shall be conducted on guaranteed losses.

The transformer shall be capable of giving continuous rated output without exceeding the

specified temperature rise. Bids not meeting the above limits of temperature rise will be treated as non responsive.

575

The Hot spot temperature at annual weighted average ambient temperature of 35o C shall not exceed 98o C, when calculated as per IS: 2026 ( Part-II)

However, the transformer shall be designed for class ‘A’ insulation.

8. UNBALANCE CURRENT:

The maximum value of unbalance current in transformers shall not exceed 2% of full load current.

9. IMPEDANCE:

The percentage impedance at rated current and at 75°C shall be 4.5 % with (+/-) 10 % tolerance.

10. TAPPINGS: No taps are to be provided in these transformers.

11. FREQUENCY: Transformers shall be designed for normal frequency of 50 Hz, but shall be capable of giving

the rated output with the variation of (+/-) 3 % from the rated frequency. 12. ELECTRICAL CLEARANCES:

(A) EXTERNAL (IN AIR)

Minimum external electrical clearances after mounting the bimetallic terminal connectors in position shall be maintained, as under, however positive tolerance shall be acceptable without any ceiling.

Voltage Medium Clearance

Phase to phase Phase to earth

11000 Volt A I R 255 mm 140 mm

433 Volt A I R 75 mm 40 mm

B) INTERNAL (IN OIL):

The following minimum internal clearances shall be maintained as per details given hereunder:

PARTICULARS 25 KVA

a) Between HT outside surface & tank inside (non bushing side) 25 mm

b) Between HT outside surface & tank inside. (HV bushing side) 40 mm

576

c) Between HT outside surface & tank inside. (LV bushing side) 25 mm

d) Between HV windings & yokes (end insulation) 20 mm

e) Between LV windings to core(Bare conductor) 3.5 mm

f) From top of yoke to inside of top cover of tank (with gasket) 125 mm

g) Between LT/HT winding (Radial bare conductor Clearance ) 11 mm

h) Phase to Phase Clearance between HV limbs 10 mm

The aforesaid external and internal clearances are minimum clearances and no negative tolerance on these clearances shall be allowed.

13. TEST VOLTAGE:

Transformers shall be capable of withstanding the power frequency and impulse test voltage prescribed below:

Nominal system Voltage (RMS)

Highest system voltage (RMS)

Impulse withstand voltage

Power frequency test voltage in (RMS)

11 KV 12 KV 95 KV (PEAK) 28 KV

0.433 KV ---- ---- 3 KV

The Transformer shall have fully insulated windings designed for the above impulse level.

14. HEAT DISSIPATION (COOLING) / RADIATOR CALCULATIONS & E T R

(ELLIPTICAL TUBE RADIATORS) PLACEMENT:

The transformers shall be capable of giving a continuous output without exceeding the specified temperature rise. Only Elliptical tube radiators of section 57 of gauge 18 (with tolerance as per relevant ISS) shall be acceptable on the transformers.

The radiator tubes shall be arranged in two equal banks fixed at two opposite non bushing

sides. The header pipe connecting radiator bank to the tank shall be rectangular in shape with approximate size of 100x20 mm. alternatively round pipe of dia 32 mm can also be used for connecting the radiator bank to the tank. The placement of top header pipe to the tank body shall be above the top of yoke, to facilitate cooling for hot oil sump over top yoke.

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Cooling area of the tank/radiators should be sufficient to dissipate the guaranteed losses satisfactorily. Necessary calculations in this regard shall be furnished by the Bidder with their tender. For the purpose of heat dissipation calculations, the following criteria shall be adopted:

i) Plain surface of tank – 500 W / m2

(Note: The area of top/bottom tank surface, headers, HV/LV bushing pocket and conservator shall not be considered for purpose of above calculations).

ii) Elliptical tube of section 57 -- 55 watts/meter length. 15. WINDING AND INSULATION:

i) MATERIALS:

Double paper covered aluminium conductors shall be used for 11 KV class transformers of 25 KVA rating. The covering shall conform to IS:6162 (part I & II).

ii) CONSTRUCTION:

The High-tension windings shall be concentric with the Low-tension windings. The Arrangement of the windings shall be robust in electrical and mechanical construction and shall permit free circulation of oil and avoid hot spots. The LT conductor shall be rectangular in shape. Two layer of electrical grade insulation craft paper of 2 mil thickness or one layer of min. 4 mil thickness shall be used for interlayer insulation both for HV and LV Coils. Insulation cylinder made from electric grade pre-compressed board(s) having minimum total thickness of 1.5 mm shall be used between HV and LV windings. Alternatively 20 mil pressphan paper making thickness of the cylinder 1.5 mm having similar electrical properties may also be used.

For phase barrier, 2 Nos. of 1 mm thick press board shall be used for

covering the tie rods. Besides, tie rods shall be covered by SRBP tubes of suitable size.

2 mm press board shall be used for base support insulation and core clamping channel insulation. For bottom and top yoke insulation, only PC Board of min. 2 mm thickness will be used. Also, vertical spacers between HV and LV coils and radial spacers (tickleys)/ blocks etc. shall be of PC Board only.

Top layer of all HV coil shall be given one coat of air dying insulation varnish.

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A tolerance of upto plus minus 1% shall be permissible on ID and OD and axial length of HV and LV coils. However, the above tolerances are subject to maintaining the min. required clearances. The material and thickness of various insulation provided for phase barrier, foot plate insulation, yoke insulation and core clamp insulation shall be clearly indicated in the drawing and in any case shall not be inferior to those used in type tested transformers.

Min. number of coils on HV side shall be 4 (four) per phase for 25 KVA

transformers. Dovetailed shaped radial spacers shall be placed between HV coil sections, suitably – locked with vertical spacers around the circumference of the coils. The number of such spacers shall be minimum 4(four).

Current Density

The current density for HV and LV conductor shall not exceed the value given hereunder:

Rating Current density in Amp. / mm Sq.

25 KVA

HV winding LV winding

1.35 1.60

iii) INSULATION MATERIAL:

Electrical grade insulating Kraft paper of only Triveni / Ballarpur / Padamjee shall be used. Press Board used shall be of senapathy whitely / Raman make. Perma wood or haldu wood blocks shall be used for Top and Bottom yoke insulation.

iv) CONNECTIONS AND TERMINATIONS:

A) HV Winding: The following method shall be adopted for taking out HV connections- a) The coil series connections shall be made by soldering / brazing only, after completely

removing the insulation from the ends.

(b) Starting and finishing leads of HT coils shall be covered with empire sleeve(s) of proper size. These leads should be clamped with the body of the winding with the help of cotton twine during manufacture of the coils.

c) All delta leads from the HT coils as well as HT line leads shall be taken out through multiple paper covered (MPC) copper wires of sufficient cross section area to impart the desired mechanical strength. The current density in HV lead wire shall not exceed 0.8 A/mm². These lead wires shall be provided with multi layer paper insulation of minimum 1.0 mm thickness i.e. minimum increase in diameter due to

579

paper insulation shall not be less than 2 mm. The layer of glass sleeves/ glass tape shall also be provided on the delta MPC wire and it should be further covered with minimum 12 mm dia SRBP tube. The SRBP tube shall be extended in such a way that it is entered upto 50% of bushing height.

d) All the above leads shall then be clamped tightly with cotton twine directly on to the special frame/bracket making “Pie” shape connection. This structure could be made up of Bakelite/ Permalli wood/ laminated PC board flats, having minimum size of 25x4.5 mm for 25 KVA Transformers. Line leads leading to the HV bushing terminals shall be directly clamped to the horizontal support bar of the “Pie” structure so that any tension which may develop in the HT leads due to jerks or at the time of making the connection , is not passed to the HT coils.

e) Delta joint and lead from delta joint to bushing rod shall be made by brazing only. B) LV Winding :

(a) The LV connection shall be taken out by cut on the top yoke channel duly reinforced to compensate for the mechanical strength.

b) The layers in LT Coil may be either even or odd in numbers but minimum layers shall be two.

c) LV star point shall be formed of aluminium flat of sufficient strength. Leads from winding shall be connected to the flat by brazing.

d) Firm connection of LT winding to bushing shall be made of adequate size of “L shape flat”. Connection of LT coils to L shape flat shall be by brazing only.

e) “L” shape Flat shall be clamped to LV Bushing metal part(s) by using nut, lock nut and washer.

f) Neutral of the Secondary winding (LV) shall be brought out to a separate insulated bushing.

g ) For Aluminium windings, L&T, ALKAPEE Aluminium brazing rods with suitable

flux will be used.

16. CORE CONSTRUCTION & CORE COIL ASSEMBLY DETAILS:

A. CRGO CORE:

(i) The core shall be stack/ wound type of generally high grade cold rolled grain oriented

annealed steel laminations, having low loss and good grain properties, coated with hot oil proof insulation, bolted together to the frames firmly to prevent vibration or noise. All core clamping bolts shall be effectively insulated. The complete design of core must ensure the permanency of the core losses with continuous working of the transformers. The value of the flux density allowed in the designs and grade of laminations used shall be clearly stated in the offer, along with the curves. The transformer core shall be constructed out of the prime class of materials. CRGO/ amorphous Lamination used shall be of prime grade and not second grade steel laminations.

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(ii) It will be mandatory for all the transformer manufacturers to use only PRIME grade CRGO Laminations with specific loss of 0.89 watt per kg. at 1.5 Tesla or any other combination of better grades with any thickness subject to maximum specific loss of 0.89 watt per kg. at 1.5 Tesla will also be acceptable. The bidder shall furnish the core loss (watt/Kg.) and power (VA/Kg) curves of the laminations used. The core shall be properly stress relieved by annealing in inert atmosphere. The transformer shall be suitable for over fluxing (due to combined effect of voltage and frequency) upto 12.5% without injurious heating. The operating flux density shall be such that there is a clear safe margin over the fluxing limit of 12.5%.

(iii) Full mitred core construction technique for stack core shall be adopted. Top yoke & bottom yoke pieces shall all be in one single piece and no cut pieces shall be acceptable. The cross sectional area of yoke & limb shall be approximately same.

(iv) The transformer core shall not get saturated for any value of V/f ratio to the

extent of 115 % of the rated value of V/f ratio (i.e. 11000/ 50) due to combined effect of voltage and frequency without injurious heating at full load conditions. The bidder shall furnish necessary design data in support of this situation.

(v) The flux density at rated voltage and frequency of core and yoke shall not be more

than 1.6 Tesla. The Over fluxing shall be limited to 12.5% of rated value and flux density at 112.5% of rated voltage does not exceeds by 1.9 Tesla. (as per amended IS:1180 (Part-I/2014) Actual core design along with calculations in support of it should be enclosed with the offer.

The No Load Current (magnetising current) at rated voltage and at 112.5% of rated voltage shall not exceed the values given below:

Maximum permissible magnetising current in percentage of rated full load current

Rating At 100% rated voltage At 112.5% rated voltage

25 KVA 3.00 6.00

The tolerance on magnetizing current shall be +30% on declared value of magnetizing current as per IS: 2026.

Vi) Core clamping :

a) MS Channel of 75 x 40 mm min. size shall be used on top and bottom (for stacked core transformers).

b) 2 x 12 mm high tensile bolts to be used in parallel at each end.

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c) Channel on LV side to be reinforced at equidistance, if holes/cutting is done for LT lead in order to avoid bending of channel.

d) MS channel shall be painted with varnish or oil-resistant paint. e) Tie-rods : 4 Nos. of M12 M.S steel rods shall be effectively insulated. f) All top and bottom yoke nuts & bolts and tie rods shall be painted with oil and corrosion-

resistant paint and phosphate coated paint for tie rods before use. g) Only prime quality CRGO sheets should be used in the transformers and no

Second/Defective/ Scrap CRGO finds way into transformers.

B. AMORPHOUS METAL: a) The core shall be high quality amorphous ribbons having very low loss formed into wound

cores of rectangular shape, bolted together to the frames firmly to prevent vibration or noise. The complete design of core must ensure permanency of the core loss with continuous working of the transformers. The value of the flux density allowed in the design shall be clearly stated in the offer. Curve showing the properties of the metal shall be attached with the offer.

b) Core Clamping – Amorphous Metal and CRGO wound core Transformers 1. Core clamping shall be with top and bottom U-shaped core clamps made of sheet steel clamped with MS tie rods for efficient clamping.

2. MS core clamps shall be painted with varnish or hot oil resistant paint

3. Suitable provision shall be made in the bottom core clamp / bottom plate of the transformer to Arrest movement of the active part.

c) The transformer core shall be suitable for over fluxing due to combined effect of voltage and frequency upto 12.5% without injurious heating at full load conditions and shall not get saturated. The Bidder shall furnish necessary design data in support of this situation.

d) Flux density should not be more than 1.6 Tesla for Amorphous core. No load current shall not exceed 3% of full load current and will be measured by energizing the transformer at 433 volts 50 c/s on the secondary. Increase of voltage of 433 volts by 12.5% shall not increase the no load current disproportionately high and shall not exceed i.e., 6%. Test for magnetic balance by connecting the LV phase by phase to rated phase voltage and measurement of an, bn, cn voltage will be

carried out.

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NOTE : Equal Weightage shall be given to the transformers with Amorphous metal core and CRGO.

(C) CORE-COIL ASSEMBLY:

The core joints shall be interleaved and with full mitre design, as mentioned above. Ample provision for free circulation of oil in the radial gap between the core & LV coils shall be made. Eyes or lugs of sufficient size shall be provided for lifting core and winding assembly out of the tank. The core shall be effectively earthed through tinned copper earthing plate bolted on core frame channels, after removing the channel paint.

For top yoke channels, if cut or holes are made for taking LV connections, suitable

reinforcement to channels shall be made by providing adequate size of MS Flat of the thickness not less than 6 mm.

On the core-coil assembly, core clamping channels, tie rods, core studs, spacers, assembly

base supports, etc. shall be provided as per details given hereunder:

Sr. No.

Item Particulars

a) Tie rods Minimum 4 Nos. of 12 mm each properly insulated and covered with SRBP tubes. Tie rods shall also be provided with lock nuts.

b) Core studs Minimum 4 Nos. of 12 mm each properly insulated and covered with SRBP tubes. The core studs shall also be provided with lock nuts.

c) Spacers Minimum 4 Nos. dovetail type with min. peripheral coverage of 30%.

d) Support of core assembly base

2 Nos. MS channels OF 75x40 mm.

e) Channels for clamping core coil assembly

4 MS Channels of 75 x 40 mm size (applicable for CRGO transformers)

Guides on all the four sides shall be provided to prevent shifting of the active parts and thereby accidental touching the tank. Alternatively boss nut arrangement at the top of core coil assembly to lock the same with the transformer tank be provided.

The assembly fixing boss nut(s) are to be welded,20-30 mm off the centre line (and

diagonally) of the tanks, so that assembly shifting during transport etc. is prevented. M S Channel, tie Rods etc should be painted with hot oil and corrosion resistant paint after phospating.

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All core-coil assembly shall be punched on core channel / a identity plate welded on core channel with following details:

1. Name of Supplier:

2. IPDS. / TN No:

3. Rating:

In case if above marking is not found on the core assembly of physically opened transformer

selected for physical verification during final inspection then no further inspection shall be carried out and re-inspection charges shall be payable by the supplier.

17. TRANSFORMER TANK: (a) Transformer tank shall be rectangular in shape, robust in construction and with adequate strength to withstand the pressures developed at the time of severe fault conditions. The tank body shall be suitably stiffened to achieve the object. The tank sheet shall be electrically welded both from inside and outside to impart proper mechanical strength and to plug leakage of oil. All joints of tank and fittings shall be oil tight and no bulging shall occur during service. The tank design shall be such that the core and windings can be lifted freely. The tank plates shall be of such strength that the complete transformer when filled with oil may be lifted bodily by means of lifting lugs provided. The stiffeners shall be welded full length. All the welding shall be continuous. The top cover plate shall be sloping down by more than 15 mm, opposite LV bushings side. The top cover instead of bending shall be extended by 5 mm by all the sides beyond the flange of the top cover. Accordingly length of the lifting hooks shall be extended. The top cover shall have no cut at point of lifting lug. No negative tolerance in the tank dimensions is acceptable in actual supply. The tank shall be fabricated by welding at corners. No horizontal or vertical joints in tank side walls and its bottom and top cover will be allowed.

(b) (i) Minimum size of MS Sections to be used in construction of transformer tanks shall be as under:

Sr. No.

I T E M S 25 KVA

1 Tank Cover plate thickness (mm) 5.0 t

2 Tank Sides wall thickness (mm) 3.15 t

3 Tank bottom plate thickness (mm) 5.0 t

4 Conservator body (mm) 2.0 t

5 Detachable Conservator side Cover N.A.

6 No. of stiffeners (To be welded with one face while the

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other side of the angle forms inverted “L”) 1

7 Size of M. S. stiffener (mm) 40x40x 6 angle

8 Tank Top flange size (mm) 50 x 6 t Flat

9 Cover Bolt Size M10/ 3/8 x 1.5”

10 Cover Bolt spacings (Maximum) 75 mm

11 Lifting lugs 2 Nos.

8t mm flat

12 Tank Base Channel of size 75x40 mm (weight = 7.14 Kg./mtr.) ISMC Type 2 ( 75 x 40 mm)

NOTE: Each cover bolt shall be complete with two flat washers, one nut and one spring washer.

The 12 Nos. nuts & bolts (4 Nos. each on length sides and 2 Nos. each on width sides of tank body) to be tag welded on top cover/ tank body of transformer.

The 04 Nos. Anti Theft Fasteners shall be provided - one each on all four sides in centre of

body of transformer.

Two holes shall be provided – one on top cover and other on collar of transformer to facilitate providing of 2 Nos. poly-carbonate seals on longitudinal side.

The supplier shall provide additional 8 Nos. stainless steel anti theft fasteners (nuts and bolts) for fixing the base channel on structure.

The above mentioned M S sections shall be subject to tolerance as per ISS.

(b) (ii) MEASUREMENT OF SHEET THICKNESS OF TRANSFORMER TANK/ METER

& PROTECTION BOX:

The following measurements shall be carried out at respective Central Testing Lab (CTL) of the Discom(s) on the supplies of distribution transformers:

Measurement of Transformer Tank Thickness shall be done as follows:-

1. Top Cover At 2 places to be measured & average is to be taken.

2. Bottom Cover -do-

3. Side Wall(s) On all four sides (average is to be taken)

4. M&P Box. Both sides and front (average is to be taken)

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· The nominal value of sheet thickness will be considered as mentioned in the Specification.

·· Rolling tolerance will be as per ISS:1852-1985 with latest amendment and no penalty will be charged on such measured thickness till tolerance limit of ISS.

··· Sheet thickness of transformer tank/ M&P Box for Distribution Transformers as per relevant tender specification are as under for ready reference:

Sr.

No.

Rating Top Cover (mm)

Bottom Cover (mm)

Side of Tank

(mm)

M&P Box

(mm)

1 25 KVA Three Phase 5.0 5.0 3.15 2.0

Further it is also intimated that 5% variation beyond tolerance limit in measurement of sheet thickness shall be acceptable by the Discom with levy of penalty. The rate of penalty will be Rs.80.00 per Kg.

For example:

Weight of 25 KVA Transformer Tank and M&P Box

120 Kg. (approx.)

Variation in thickness of tank/M&P Box 5% (beyond tolerance limit)

Then penalty levied will be 120x80x5 = Rs.480.00

-------------

100

In case any dimension in transformer tank/ M&P Box sheet thickness found beyond aforesaid limit of 5% will not be acceptable to the Discom and the relevant sub- lot shall stand rejected and the lot of such transformers will have to be replaced by the firm.

Transformer having thickness even more than 5% after allowing rolling tolerance

shall be acceptable.

The highest percentage variation on negative side in respect of measurement of sheet thickness of any part of tank & M&P Box will be applicable on the entire dimensions for levy of penalty.

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The sheet thickness measurements will be carried out on all those sample transformers which are tested in CTL and test results will be applicable to the respective sub-lot or part thereof from which the sample is drawn.

(c ) Lifting Lugs: Two Nos. welded heavy duty lifting lugs of MS plate of 8 mm thickness, suitably reinforced by vertical supporting flat welded edge wise below the lug on side wall shall be provided, these shall be so extended that cutting of bent plate is not required

(d) Top cover gasket & Bolt:

i) The gasket of provided in between top cover plate and tank shall be of min. 6 mm thick neoprene rubberized oil resistant cork sheets conforming to type B or C as per IS 4253 part II.

ii) G.I. Nut bolts shall be of size M 10 x 40 mm / 3/8x1.5” long with two flat washers, suitably spaced (as specified) to press the cover.

iii) Height of the tank shall be such that minimum clear height of 125 mm for 25 KVA rating is achieved between top of yoke and under side of the tank cover (with gasket in place).

iv) All steel screws, nuts and fasteners exposed to atmosphere shall be either galvanised or cadmium plated or electroplated.

v) All sealing washers / gaskets shall be made of oil and heat resistant neoprene or nitrile rubber. Gaskets made of natural rubber sheet are not permissible. The

minimum thickness of gaskets shall not be less than 6 mm for tank cover and 4 mm for HT/LT gasket washers.

vi) New cork/ Talbros make neoprene/nitrile based rubberized cork sheet – grade RC-70-C

shall only be used as gasket material.

e) Tank shall be reinforced by continuously welded angle on all the four sides of the walls, on the edge of tank, as specified above. The permanent deflection shall not be more than 5 mm upto 750 mm length and 6.5 mm upto 1250 mm length when transformer tank without oil is subjected to the vacuum of 250 mm of Mercury.

f). PAINTING & FINISHING:

Steel surface shall be prepared by sand / shot blast or chemical cleaning including

phospating, as per IS 3618. Heat resistance paint (Hot oil proof) shall be provided inside tank. On external surface, one coat of thermo-setting powder paint or 2 coat of Zinc chromate followed by two coat of olive green colour conforming to Shade No. 220 of IS –5 of 1961 in order to distinguish of star level transformers, shall be applied.

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The requirement for paint and the material to be used as below.

Paint Type Area to be Painted No. of coats

a) powder Paint b) Thermo Setting Powder

Inside

Outside

01 01

LIQUID PAINT a) Zinc Chromate (Primer)

b)synthetic Enamel (finish coat)

c) Hot Oil Paint

Outside

Outside

Inside

02

02

01

All steel screws, nuts and fasteners exposed to atmosphere shall be either galvanized or cadmium plated.

g) The IPDS/ TN No., Sr. No. of the transformer and name of the manufacturer should be punched/ embossed on top cover/ bottom cover/ sides of tank body (size of letter 10x5 mm).

18. FITTINGS & ACCESSORIES: The following standard fittings shall be provided on each transformer:

a) Earthing terminals of M10x40mm/3/8x1.5” with tinned lugs and symbol – (2 Nos.) b) Lifting lugs – (2 Nos. for main tank). c) Rating and terminal marking plate (non-detachable), details to be included

in one plate only. The plate shall be of stainless steel only, with details

clearly marked - (1 No.) d) Bi-metallic terminal connectors on HT bushings and it may be ensured that connectors shall be

fitted before dispatch. e) Oil level gauge of minimum 150 mm length of prismatic glass, indicating three positions of oil, marked as follows, shall be provided:

1) -5 °C - Min.

2) 30 °C - Nor.

3) 98 °C – Max.

f) Silica Gel Breather shall be aluminium/ metal – (1 No.) g) Thermometer pocket, 12.5 mm dia with cap. shall be provided –– (1 No.) h) HV BUSHING: These shall be of 17.5 KV/ 250 Amp. Class porcelain/ polycrate with non

adjustable, single gap type arcing horns – (3 Nos.). i) LV BUSHING: 1.1 KV/ 250 Amp. Class porcelain/ polycrate (M12 stem) – 4 Nos.

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j) Under carriage: For transformers of 25 KVA rating shall conform to REC specifications.

k) Brass rod 12 mm diameter for HT – (3 Nos.)l) Brass rod 12 mm diameter for LT – (4 Nos.)Note: LV/ HV Connectors shall not be the integral part of the bushing stems.

19. CONSERVATOR:

When a conservator is fitted, the oil gauge and the breathing device shall be fixed to the

conservator. In addition, the cover of the main tank shall be provided with a self-sealing pressure release device designed to operate at minimum pressure of 8 PSI (0.564 Kg./cm. Sq.) to enable release of air trapped within the main tank, unless the conservator is so located as to eliminate the possibility of air being trapped within the main tank. The conservator shall be of cylindrical shape and it should be provided above the HV bushing with a minimum clearance of 50 mm and suitably inclined to maintain the clearance.

The total inner volume of conservator shall be minimum 10 ltr. for 25KVA transformer. The inside diameter of the pipe connecting the conservator to a main tank shall be min. of 30 mm and it should be projected into conservator in such a way that its end is approximately 25 mm above the bottom of conservator so as to create a sump for collection of impurities. The min. oil level (corresponding to – 5 deg. C.) should be above the sump level. The connecting pipe from conservator tank to main tank shall have a sloping flap so that oil falling from pipe shall not fall directly on the active job.

Apart from the features specified in this clause for conservator tank, the oil filling hole cap of conservator shall be welded with tank body with the help of suitable inverted ‘U’ shape clamp.

20. SILICAGEL BREATHER:

Body of breather shall be of aluminium/ metal and inside container for Silica gel shall be of tin sheet. The breather shall be only from reputed and approved manufacturer and as per the approved drawing. The gel capacity shall be of 250 grams. Inverted U shape pipe shall be used for breather. Mounting arrangement of the breather shall be flanged/ threaded type as per details given in the illustrative drawing attached.

The design shall be such that the condition of Silica gel is clearly visible from a distance, even

after years of service.

21. A) H V BUSHING TERMINAL DETAILS :

3 Nos. 17.5 KV / 250 A class bushings, conforming to IS:3347 & IS:2099, shall be fitted on a pocket made on top cover. These pockets shall be such that the HV bushing is tilted more towards the HV side. The bushing of R & B phases may also be tilted sidewise to maintain the required electrical clearances. The HV bushings opposite to LV bushings on side of the tank shall also be acceptable.

589

The clamping ring of HV bushing shall be of galvanised MS Sheet having minimum thickness of 1.6 mm. The total weight of all the 12 aluminium caste member of HV bushing shall not be less than 210 grams.

The inner porcelain portion of bushings shall be projecting approx. 50% of the length inside

the conical pocket. HT bushing (s) mounting bolts should be tag welded.

The arcing horn(s) shall be single gap and fixed type. HV bushings shall be of reputed make such as BEPCO, JAYSHREE, WSI, SESHASAYEE, JAIPUR GLASS, BPPL Bikaner, Agarwal salt Co. Bikaner, Bais Sanitary Works, Bikaner, Krishna Ceramics, Nasirabad or any other make - approved by the purchaser. The HV bushings shall generally conform to IS: 3347 and IS: 2099. Embossing showing the manufacturer’s name and month & year of manufacture shall be clearly visible on HV bushings, even after fixing on transformer(s).

As mentioned earlier, suitable bi-metallic connectors shall be provided in lieu of ‘Note’ at page

14; Cl.18 (i), having capacity of about 1.5 times the rated current of the transformer.

B) L V BUSHING TERMINAL DETAILS:

LV Bushing side shall be opposite to the HV Bushing side. 4 Nos. LV Bushings (1.1 KV/ 250 A) shall be mounted on a special pocket on the tank wall. Projection of the LV pocket shall be such that inner portion of the LV stem shall not project more than 20 mm inside the tank, to facilitate unhindered lifting of the core coil assembly. Bushing stem of M12 size shall be of brass. Rest of the components shall conform to the requirement of IS:3347 (Part I/section 2). The LV bushings shall be of reputed make such as JSI, JAIPUR GLASS, BPPL Bikaner, Baid Sanitary Works, Bikaner, Agarwal salt Co. Bikaner, or any other make approved by the purchaser. The LV bushings shall generally conform to IS: 3347 and IS: 7421.

22. TRANSFORMER OIL:

The transformer shall be supplied complete with first filling of EHV Grade transformer oil, up to the normal oil level. The oil shall conform to IS: 335-1993 (latest amended) and should be ISI Marked and having the specified aging characteristics.

The make of Transformer Oil shall be either APAR/SAVITA/ RAJ LUBRICANTS/ ANAMIKA/SHARAVATI/ MADRAS PETRO/ RAJ PETROL/ LUBRICHEM, MUMBAI/ OPANAMA PETROCHEM, ANKELSHWAR/ TASHKENT OIL, VADODARA/ COLUMBIA. The transformer oil sample taken from the transformer shall be subject to testing as per provisions of IS:1866.

The oil manufacturer’s test certificate shall be made available at the time of inspection to the inspecting officer.

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23. IDENTIFICATION DETAILS: A) Rating & terminal marking plate: Each Transformer shall be provided with non

detachable name, rating and terminal marking plate fitted in a visible position. All details shall be given on one plate. Material of the plate shall be stainless steel only. Thickness shall be 0.9 mm (with a tolerance of ±0.1 mm). The plate shall be made absolutely undetectable either through welding or riveting or through any other approved method.

Each HV & LV terminal shall be duly marked with its terminal numbers. (e.g. HV terminal with capital letter 1U, 1V, 1W and LV terminal by corresponding small letters) 2u, 2v, 2w and the neutral terminal by 2n). In the diagram to be given on the name plate, the relative position of various terminals- when viewed from top – shall be clearly shown. Inspection shall not be undertaken unless all these details are verified by the Inspecting Officer.

Besides other particulars, following details shall also be given on the name plate:

i) P.O. No. - month & year. ii) IPDS/TN No. iii) Sr. No. of transformer. iv) Date of dispatch - month & year v) Date of expiry of guarantee period – month & year vi) Maximum Guaranteed Losses at 50% loading & at 100% loading. vii) Recommended fuse sizes for HV & LV sides. viii) Name & Full address of the manufacturer. ix) Capacity of the transformer. x) Rating of the transformer. xi) Type – Oil filled naturally cooled.

ALL DETAILS ON THE NAME RATING AND DIAGRAM PLATE SHALL BE INDELIBLY MARKED i.e. BY ENGRAVING, STAMPING or PUNCHING.

B) Identification Plate :- M.S. plate of size 125 x 75 x 2.5 mm having following details punched with letters of size 8mm X 6mm shall be continuously welded to the main tank body below the middle HV bushing and on top cover of tank in clearly visible position :

JAIPUR DISCOM IPDS/TN No. ------- ……… KVA , S.NO. ……….

MAKE …………….

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Further following details is to be punched on all the four sides of the tank preferably in center. The dimensions of letters should be 10x10x1 mm. The punching shall be distinct and visible.

a) Make b) IPDS/TN No. c) Sr.No.

To punch the details make, IPDS/TN No. & Sr.No.of transformer at two places ( i.e. at the top cover & transformer tank). The punching shall be distinct and visible.

(C) Technical Plate- In addition to existing provision of identity plate and name plate one plate also be affixed on the transformer mentioning the following details:-

A) Name of the Firm B) IPDS/TN No. C) Make D) Rating E) Core :-

1. Core Dia 2. Core Area

F) LV Coil :- 1. ID/OD Dimensions 2. Conductor Size

G) HV Coil :- 1. ID/OD Dimensions 2. Conductor Size

H) Limb Centre I) Window Hight

24. GUARANTEED AND OTHER TECHNICAL PARTICULARS FOR TRANSFORMERS:

Guaranteed Technical particulars of the transformers offered shall be furnished in A-4 size paper in the proforma appended herewith at (Schedule-A). Complete details shall be furnished. Tolerances on weight quantity and dimension figures shall be ± 5% (except for internal configuration) at the tender stage, subject to maintaining the minimum electrical clearances as per the specification. However, no negative tolerance shall be allowed on the short circuit type tested design. Electrical performance data shall be subject to tolerances as per ISS, unless otherwise specified in this specification. However, the Total losses (at 50% and100% Loading) shall be maximum guaranteed without any positive tolerance.

592

25. TYPE TEST CERTIFICATES:

The bidder shall furnish type test certificates of similar design submitted for BEE labelling ( not older than 5 years) wherever available, with the bid.

26. DRAWINGS AND OTHER DOCUMENTS:

The supplier shall be accompanied with the following drawings / Calculation sheets, as per the offered designs. The drawings shall be only on A-3 (420 x 297 mm) size paper and calculation sheet shall be on A-4 size paper only.

a) Name rating / diagram plate drawing. b) Outline and general arrangement drawing. c) Core-coil assembly drawing. d) Core section (for limb and yoke) along with flux density calculation sheet / drawing. e) Cooling area calculation sheet. f) Thermal Ability short circuit calculation sheet. g) Core loss and magnetization curves of the laminations. h) Heat dissipation calculations (heat dissipation by tank walls excluding top and bottom

should be 500 W/sq.meter. 27. QUALITY ASSURANCE PLAN:

The purchaser intends to purchase Transformers only from quality conscious manufacturers.

The supplier shall furnish the details of type tests conducted on the Transformers offered to supply

The tenderer should possess adequate facilities for inspection and testing of the Transformers, as per requirement of the relevant ISS and this specification. In case any supplier is found not having all the instruments/equipment required for testing, the offer shall be ignored. No borrowing of instruments / equipment shall be allowed. Testing of the Transformers shall also not be allowed at the works of any other manufacturer. However, testing may be allowed at any Government Testing Laboratory. 28. INSPECTION AND TESTING:

(i) The inspection and testing shall be conducted at the place of manufacture.

The transformers shall be completely assembled and tested at the factory. The inspection may be carried out by the purchaser at any stage of manufacturing. The supplier shall grant free access to the purchaser’s representative at all reasonable times when the manufacturing work is in progress. Inspection and testing of any material under this specification by the purchaser shall not relieve the supplier of his obligation of supplying the material in accordance with the specification and shall not prevent subsequent rejection if the material is found to be defective.

593

(ii) The supplier shall afford the inspector representing the purchaser all reasonable facilities, without charge, to satisfy him that the material is being manufactured in accordance with the specification. The bidders must have adequate set of instruments for conducting testing as per ISS/ Specification. The instruments for measurement of losses shall be of accuracy class of 0.5 or better. The instruments shall be duly calibrated and Calibration Certificate should not be older than one year on the date of presentation to the Inspecting Officer. The calibration shall be arranged from NABL accredited testing house. A comprehensive list of testing equipment/ instruments indicating make, Sr.No., type, class of accuracy, calibrating agency, calibration date etc. should be furnished alongwith the bid. The calibrated instruments shall be duly sealed by calibrating agency to avoid any tampering with calibration and the details thereof shall be clearly mentioned in the Calibration Certificate(s).

(iii) The supplier shall keep the purchaser informed in advance, about the

manufacturing programme so that arrangements can be made for inspection. The supplier shall give minimum fifteen days advance intimation to enable the purchaser to depute his authorised representative for inspection/ witnessing of various tests on the equipment/ material as detailed below:

NOTE:- Penal provision shall be made for any short technical parameters found / noticed in the transformers at any time even beyond guarantee period.

29. ROUTINE/ ACCEPTANCE TESTS:

A) 100% testing of the Distribution Transformers shall be carried out at firm’s works for measurement of total load losses at 50% & 100 % loading. Remaining testing shall also continue to be carried out as per practice.

B) All the assembled/ finished transformers prior to dispatch shall be subjected to routine tests as

per IS:2026. Minimum 25% of the offered lot size samples subject to minimum 5 Nos will be taken for routine and acceptance tests. The supplier shall invariably furnish manufacturer’s routine test certificate along with inspection call of the offered transformers for pre-dispatch inspection. The inspection offers without furnishing of routine test certificates as per ISS of all the transformers offered for final inspection shall not be entertained, and any delay on this account shall be to firm’s account.

The selected samples shall be subjected to the following routine / acceptance tests at the manufacturer’s works in accordance with the relevant ISS:

1. Insulation resistance

2. Separate source voltage withstand test

594

3. Induced over voltage withstand test 4. Measurement of windings resistance cold (at or near the test bed temperature)

5. Measurement of Voltage ratio and check of voltage vector relationship

6. Measurement of Impedance voltage.

7. Measurement of total losses at rated voltage and normal frequency (at 50% & 100%

loading). 8. Measurement of No load current at 100 % and 112.5% of rated voltage and normal

frequency.

9. Checking of rating and terminal marking plate. 10. Checking of weights , dimensions, fittings and accessories, tank sheet thickness, oil quantity ,

material, finish , paint thickness and workmanship as per purchase order and contract drawings.

11. Physical verification of core – coil dimension, internal clearances, provisions of required oil

ducts in the HV and LV winding, conductor sizes, individual weights of HV and LV winding core laminations etc., with reference to contract drawings and type test report(s) by dismantling selected unit(s). The physical verification shall be conducted on units equivalent to one unit per 50 Nos or part thereof of offered quantity randomly selected from the offered lot. The dismantled unit(s) after re-assembly shall be accepted by the purchaser after routine testing in presence of his representative.

12. Oil dielectric strength (break down voltage) test shall be carried out on the transformers

opened for physical verification and average value shall be calculated. 13. Checking of manufacturer’s test certificates and invoices for major raw materials

shall be done and copies thereof duly signed by firm’s representatives and inspecting officers shall be enclosed with the inspection report.

Invoices of CRGO/ AMORPHOUS material shall be provided by the supplier to the

inspecting officer at the time of inspection and same shall be verified by the inspecting officer.

Following tests shall also be carried out at manufacturer’s works on one complete

unit of 25 KVA Transformers unit :

i) Air pressure test on empty tank of transformer opened for physical verification test. (See note below)

ii) Over Flux Density Test (in the first lot and may be repeated in subsequent lots if desired by purchaser).

iii) Measurement of unbalance current. iv) Magnetic Balance Test (See note below) v) Oil Leakage Test (See note below)

595

Fifteen days clear notice shall be arranged for pre-despatch inspection by purchaser’s representative

After successful inspection, the inspecting officer shall seal each and every

transformer by sealing the transformer with 2 Nos. poly-carbonate seals on longitudinal side as per the manner mentioned in Clause No. 17 above. Before sealing, the inspecting officer will ensure that all the offered transformers are completed and duly fitted with name, rating and diagram plate, identification plate (on tank body & Top cover) as specified in this specification.

Also after inspection/ testing, inspecting officer(s) shall affix Signature

Seals also on each Transformer in addition to other seals.

INSULATION RESISTANCE MEASUREMENT:

Insulation resistance of selected samples shall be measured with a 2500 V Megger, of standard make such as M/s AVO, M/s Sakova, M/s Wako, M/s Evershed, Vignole or Metrawatt. The minimum insulation resistance, in Mega Ohms, shall be as indicated in the table below:

200 C. 300 C. 400 C. 500 C. 600 C. 11000 Volts (HV)

800 400 200 100 50

433 Volts (LV)

400 200 100 50 25

AIR PRESSURE TEST :

This test shall be conducted as type test at the time of inspection of first lot, at the manufacturer’s works. The pressure gauge and vacuum gauge shall be duly calibrated and sealed by an independent recognised test lab(s).

The test procedure shall be as detailed below :

The tank shall be fixed with a dummy cover with all fittings including bushings in

position and shall be subjected to air pressure of 0.8 Kg./ cm² (gauge pressure), for 30 minutes.

Permanent deflection of flat plate, after pressure has been released, shall not exceed

the values given below:

Length of plate up to Deflection

750 mm 5.0 mm 751 to 1250 mm 6.5 mm

596

iii) MAGNETIC BALANCE TEST: This test shall be conducted as an additional test on one sample transformer from

each lot offered for inspection.

The application of low voltage to the middle limb will induce approximately equal voltages on the two end limbs. The application of voltage to the end limbs will induce greater voltage in the middle limb and less voltage in the other end limb. Uniformity of induced voltages shall confirm the healthiness of the transformer windings.

The procedure for the test shall be as under : Apply 250 Volts between LV terminals-2u-2n and measure voltages between 2v-2n & 2w –

2n. Apply 250 Volts between 2v-2n and measure voltages between 2u-2n & 2w-2n. Apply 250 Volts between 2w-2n and measure voltages between 2u-2n & 2v-2n.

The measured voltages shall satisfy the conditions detailed as above. iv) OIL LEAKAGE TEST : The oil leakage test shall be conducted on one unit selected from the offered lot of each rating. Transformer complete in all respects shall be subjected to the pressure corresponding to 0.5 Kg / cm² and maintained for three hours. No leakage should occur.

30. TYPE TESTS:

The bidder shall furnish valid type test certificates of same rating of offered item from any CPRI / independent NABL Accredited laboratory/ Govt. approved lab. Such type test certificates should not be older than 5 years as on the date of opening of tender. For this purpose date of conducting type test will be considered. Type test conducted at supplier’s own NABL accredited lab shall not be considered. The following Type Test shall be conducted on one unit at NABL/Govt. Approved Lab (Details of Test given in the specification).

a) Lightening Imp. Voltage Test at 95 KVp b) Short Circuit Test c) Temperature Rise Test d) Air Pressure Test.

31.1 RANDOM SELECTION AND TESTING (RST):

Measurement of Total Losses ( at 50% and 100% Loading)

i) After pre-dispatch inspection of material at firm’s works, the dispatch instructions

will be issued for the respective store(s) as per requirement of Nigam. Sample(s) will be drawn from the lot(s) received in store(s) and will be subjected to the following test(s):

597

a) One transformer with M&P Box will be selected out of every lot of 10 Nos. or part thereof for measurement of Total Losses of transformer alongwith the losses of M&P Box at 50% & 100% loading at rated voltage; No Load current (at 100% and 112.5% of rated voltage); Impedance voltage. The testing shall be arranged either at purchaser’s own testing lab and / or at independent test lab. The testing charges for such tests shall be borne by the purchaser. The test results will be applicable to the respective lot of 10 Nos. from which sample was drawn.

Tolerance on account of M&P Box for 25 KVA distribution transformers shall be

as under:

Sr. No.

Item At 50% loading At 100% loading

1 25 KVA Three phase 6.0 W 18.0 W

ii) If dispatch instructions are less than 10 Nos. than one sample shall be

selected from each store(s) and the test results so obtained shall be for the quantity consigned/ received by store(s).

iii) Following tests / checking / verification also be carried out in CTL on one M&P Box out of 100 Nos. or part thereof selected for physical verification welded with the transformer selected for CTL testing:

a) Size of wire from MCCB to Meter. b) Size of lugs. c) Make of MCCB.

The above information shall be mentioned in the CTL Report.

The percentage impedence voltage at rated current shall not exceed the permissible limit of 4.5% with plus minus 10% tolerance failing which the sub lot of transformers represented by the sample shall be rejected.

The I.R. values of the sample(s) shall be measured at CTL, Ajmer and it must be more than 50 MEGA-OHM.

One sample out of 100 Nos. transformers or part thereof (sample whose losses are found highest in CTL testing) shall be selected for physical verification/ checking of window height, limb centre and checking of insulation of HV and LV windings at CTL.

598

NOTE:

If the total losses are found more than 10% of specified losses at 100% loading (Transformer + M&P Box) then apart from rejecting the lot, firm’s balance order would be cancelled and such firms shall not be awarded any order for one year or in next tender of tendered rating to be opened / finalized whichever is later.

If the window height and limb centre are found more than 7.5 mm, then apart from rejecting the lot, firm’s balance order would be cancelled and such firms shall not be awarded any order for one year or in next tender of tendered rating to be opened / finalized whichever is later. However, a tolerance of ± 2mm shall be allowed in window height.

No tolerance shall be allowed during CTL testing and in case any parameter which are to be tested in CTL are found beyond guaranteed parameters, the lot/ sublot shall stand rejected.

32. GUARANTEE PERIOD: Ia) For Out of Rajasthan State Firms

Performance guarantee of the transformer(s) with LT protection unit shall be for the period of 60 (sixty) months from the date of dispatch of last consignment. The date of expiry of guarantee period shall be marked on the rating plate. Transformer(s) alongwith LT protection unit failed within such guarantee period shall have to be repaired / rectified free of cost expeditiously.

Firms shall lift G.P. failed Transformers from the stores within 60 days of its intimation positively and deliver the same after repair in next 60 days. In case firm fails to lift G.P. failed Transformer within 60 days, cost of the transformer(s) shall be withheld from its payment bills and in case firm fails to deliver transformer after due repair within 120 days, a penalty at the rate of ½% per week subject to maximum 10%, shall be levied for the late delivery of repaired Transformer(s). Firm shall lift G.P. failed transformers after furnishing safe custody bank guarantee as per MM norms,

Ib) For Rajasthan State Firms Performance guarantee of the transformer(s) with LT protection unit shall be for the period of 60 (sixty) months from the date of despatch. The date of expiry of guarantee period shall be marked on the rating plate. Transformer(s) alongwith LT protection unit failed within such guarantee period shall have to be repaired / rectified free of cost expeditiously.

599

Firms shall lift G.P. failed Transformers from the stores within 60 days of its intimation positively and deliver the same after repair in next 60 days. In case firm fails to lift G.P. failed Transformer within 60 days, cost of the transformer(s) shall be withheld from its payment bills and in case firm fails to deliver transformer after due repair within 120 days, a penalty at the rate of ½% per week subject to maximum 10%, shall be levied for the late delivery of repaired Transformer(s). Firm shall lift G.P. failed transformers after furnishing safe custody bank guarantee as per MM norms

II) All the transformers repaired/ rectified by the manufacturer under guarantee clause shall carry a further guarantee of 12 months after repair or unexpired guarantee of 60 months from the date of supply, whichever is later, after repair/ rectification. The bank guarantee equivalent to cost of repaired transformers shall be furnished after expiry of performance guarantee period to cover such repair guarantee. The purchaser also reserves the right to withheld the payment of supplier firm, under any other contract, if the performance of the supplier in repaired the failed transformers is not satisfactory. Each supplier shall invariably furnish the detailed information about the total number of transformers failed and repaired by them, every month after commencement of supplies.

III) In order to ascertain that transformers have successfully completed guarantee period the following details shall be provided on the transformer body:

i) A repair identification steel plate of size 75 x 75 x 2.5 mm duly engraved with following repair details shall be welded on the transformer body.

Firm’s Name / Logo

IPDS/TN

KVA

Sr.No.

Date of supply

Date of failure

Date of repair

Guarantee period

extended.

Ist time IInd time IIIrd time

600

ii) Such metallic plate fixed on first repair should not be removed at the time of second repair or any subsequent repair. However, necessary details of failure and repair shall be graved on the repair identification plate, each time it is repaired in guarantee.

iii) The repaired G.P. failed transformer shall be provided with 40 mm wide red colour band all around transformers including radiator each time it is repaired in G.P. Thus if a transformer is repaired three time in G.P. then there should be three coloured bands each of size 40 mm.

(iv) All due care should be taken to ensure that the original name plate and identification

plate provided should not be removed from the position at which they are fixed originally. In case it is felt that these are loose then it should be repaired suitably by welding or riveting.

(v) Test checking of G.P. failed transformers will be allowed to the supplier at Nigam’s store before lifting of G.P. failed distribution transformers to repair at supplier’s works so that minor mistakes like loosing of connections/ replacement of fuse wire/ replacement of MCCB be carried out at Nigam’s stores.

(vi) G.P. repaired Distribution transformers may be got tested at CTL as per the sampling plan of new transformer except the physical opening test. A tolerance of 10% in total losses at 50% loading and 100% loading shall be allowed in G.P. repaired transformers during the testing at CTL.

(vii) An undertaking shall be furnished by the firms, who will supply the

amorphous distribution transformers that in case transformer fails beyond guarantee period, it shall be repaired by them on the rates, terms & conditions of Nigams existing CRC for repair of distribution transformers and in case firm denies to repair the transformers under CRC, such firms shall not be awarded order in subsequent tender.

NOTE:- Firm shall keep the records for at least 8 years of transformers supplied by them

33 (I) Attachment Details For Tamper Proof “Metering cum Protection (M&P)Unit

having provision of Single Meter:

600

Tamper Proof Metering & Protection unit shall be manufactured in accordance with the following Standards.

(a) The Enclosure Box shall comply with the requirement of I.S. 13947/I/1993 for Degree of Protection I.P.- 33.

(b) TP MCCB shall be in accordance with I.S. 13947/II/1993 amended up to date. (c) The MCCB will be provided by Suppliers.

The drawing and bill of material is enclosed.

General Technical Particulars :

These outdoor type cabinets are to be manufactured and supplied as complete unit suitable for fixing 1 Nos. 3 phase 4 wire whole current energy meter and modem (Meters and Modem are not in the scope of supply of bidder), alongwith 1 No. TPMCCB and wiring in sheet steel cabinet duly powder coated/ enamel painted as per clause no 17 (f) of specifications.

Cabinet :

The Enclosure shall be fabricated/ deep drawn by using CRCA sheet steel of not less than 14 SWG / 2 mm thickness with the size of 540 x 550 x 200 mm (WxHXD) & shall comply with the requirement of I.P. – 33 as per I.S. 13947/I/1993. 1st Chamber : For Transformer’s L.V. Bushings, 01 No. TP MCCB.

2nd Chamber: For Meter (Meter is not in the scope of supply of Bidder) and a space of 100 x 150 mm to accumulate one unit on modem (modem is not in the scope of supply of bidder). As per enclosed drawing.

1st Chamber :-

As shown in the drawing, this shall be in the right angle shape of size 150 mm wide to provide on the Top of the enclosure for L.V. transformer bushings and inside for mounting 01 No. triple pole MCCB. The required minimum electrical clearances as specified in clause no. 12 (A) of specification shall be maintained while providing / fixing the box.

601

2nd Chamber :-

The chamber of size 398 x 195 mm with 2 mm thick shall be designed as per drawing to be provided with Meter fixing arrangement such that front & back as well as up & down with tilting adjustment can be done to accommodate various type & make of Meter(s) and L.T. Bushing for releasing connections to consumer and space of 100 x 150 mm for providing one unit of modem as shown in drawing.

A. Main features of the ‘metering cum protection box’ are as under:

The box shall be as per drawing.

I. The single door sliding cover shall be provided with 15 mm thick triplex glass window of size 150 mm x 115 mm –1 No. for Metering Chamber to facilitate meter reading.

II. One M10 x 25 mm Bolt with Washer Isolated Earth Terminal with bushing shall be provided for body earthing.

III. 04 Nos. LT Bushing 1.1 kv / 250 Amp. as per IS:3347 brass shall be provided at right side of box to connect service line of consumer as shown in the drawing.

IV. Louvers to be provided on both sides of cabinet / enclosure. V. 3 Nos. Earth sticker with Earth Symbol to be provided.

VI. Danger Plate 125x35 mm with Hindi Language with “440V AC”. VII. All connecting wire ends should be fitted with proper lugs and properly connected except

meter terminals as detailed in drawings. VIII. Single Panel Sliding Door to cover meter chamber.

IX. MCCB operating rod to be supplied with transformer. X. A Bakelite Sheet of size 300x200x6 mm has been provided for proper fixing of the meter.

XI. Following size of lugs shall be provided for 25 KVA distribution transformers as under: Lugs for LT Terminal as per Catalogue No. 7035 / 1.80 mm – 08 Nos.

Lugs for MCCB as per Catalogue No. 7034 / 1.80 mm – 06 Nos.

Terminal ends for meter – ACP - 251 / 7.2 x 1.8 mm - 08 Nos.

Outgoing LT bushing – 1.1 KV / 250 Amp. – 04 Nos.

XII. Copy of invoices and test certificates of MCCB verified from the original(s) available with the firm is to be enclosed with the inspection report alongwith a copy of authorization letter of manufacturer to the dealer.

XIII. All the connections except LED should be through PVC covered copper flexible cable of 25 mm sq. and for LED connections 2.5 mm sq. cable shall be used.

XIV. The sliding cover shall be attached with the main body of M&P Box with the help of 02 Nos. nuts bolts each side of sliding cover (total 08 Nos. nuts bolts) as shown in the drawings.

XV. Length of Cable to be provided for connections in M&P Box shall be as under:

602

I) MCCB to Meter: Red (R) – 400 mm Yellow (Y) – 400 mm Blue (B) – 450 mm

II) From Meter to LT Distribution Terminal:

Red (R) – 600 mm Yellow (Y) – 500 mm Blue (B) – 400 mm

NOTE:

a. All dimensions are in MM. b. Sheet steel thickness: 2.0 mm (min) c. Paint shade: Exterior & Interior – olive green colour conforming to Shade No. 220 of

IS –5 of 1961 d. Degree of enclosure protection IP:33

34.1 Specification of MCCB :

The following makes of MCCB shall be acceptable :- Seimens / L & T / ABB / GE Power / Schneider – France / SPACEAGE _Hyundai/ HAVELLS/ C&S/HPL only. The MCCB shall directly be purchased from the manufacturer or the authorized dealer or stockist, however in every case of purchase of MCCB the delivery shall be from the manufacturer’s godown for which a copy of bill shall be given to inspecting officer at the time of inspection.

Three pole MCCB is to be provided on LV side with over load trip release with inverse time current characteristics for overload protection and magnetic trip release for instantaneous tripping in the wake of Short-Circuits.

These MCCB’s shall be confirming to I.S. 13947/1993 as amended upto date. The rated un-interrupted current of MCCB shall be 100 Amp. with the overload release set at 40 Amp. The type test certificate(s) as per the relevant standards of the MCCB’s meeting the below mentioned tripping characteristics shall also be furnished along with the tender.

603

The MCCB’s shall be manually independent & shall have quick make, quick break Mechanism, the detailed specification of MCCB shall be as under:

Application Outdoor (enclosed).Utilization category ‘A’ (IS: 13947/1993) as amended upto date.Type Thermal-Magnetic trip free mechanism.Number of poles Three.Reference ambient temperature 40 C.Rated insulation level 600 V.Rated operational voltage 415 V.Continuous current rating 100 AFixed overload release setting (Amp) 40 Amp. for 25 KVAUltimate Short Circuit Breaking capacity (ICU)

18 KA at 0.3 P.F. at 240 V AC.

Rated service Short Circuit Breaking capacity (ICS)

15% at 0.3 P.F.

Power factor for Short Circuit (max.) 0.3 (lag.)Application Standard IS 13947 Part-2 (latest) - 1993 Time current characteristics To co-ordinate with HV fuse.

The MCCB shall not cause any nuisance tripping due to switching current of motor & capacitor loads, and shall have the following time-current characteristics:

Multiple of normal current setting Tripping time

1.05 More than 2.5 HRS. 1.1 Less than 2.5 Hrs.

1.15 More than 1 Hr. & less than 2 Hrs.

1.2 More than 0.5 Hrs. & less than 1 Hr.

1.3 Less than 20 minutes.

1.4 Less than 10 minutes.

2.5 Less than 1 minute.

604

6.0 Less than 5 seconds.

8.0 Less than 40 milli seconds.

12.0 Instantaneous(less than 20 milli Seconds.)

For above time / current characteristics reference calibration temperature of the breaker shall be 50 degree C. Deration if any up to 60 degree C ambient temperature shall not exceed 10% of the current setting indicated above.

The Bidder shall submit the type test reports as per I.S. 13947/1993 for test sequence I,II & III complete with certified drawings, Oscillograms and approved drawing from NABL approved laboratory alongwith the offer.

The MCCB’s shall be marked with ‘Brand Name’ of manufacture and Ics in KA by embossing only whereas other particulars may be marked as per the manufacturers standard practice.

The contacts of MCCB should be self-wiping type so as to keep the contacts clean and milli- volt drop low. The MCCB shall be provided with push to trip facility.

The successful bidder shall be required to furnish the guarantee certificate of five (5) years obtained from the MCCB manufacture as per the enclosed format on Non-judicial stamp paper of appropriate value.

Acceptance Tests:

The following tests shall be carried out by purchaser’s representative on MCCB’s on the sample numbers equivalent to the number of transformers samples.

1. Overall Dimensional Checking. 2. High Voltage test at 3 kV for one minute. 3. Insulation resistance test.

605

Instruction and operation Manual

The successful bidder shall be required to submit 5 copies of Instruction and Operation manual for each lot of 100 Transformers (or part thereof) supplied. This instruction manual should give complete details about the pre-commissioning tests/checks and the details of preventive maintenance etc.

35.3 Signal Light (LED Indicating Lamp):

The MCCB enclosure shall be provided with LED indicating lamp to indicate tripping of MCCB. An auxiliary relay with changeover contacts can be used to connect LED indicating lamp to the transformer secondary terminals if MCCB is not having auxiliary contacts. In case the MCCB trips or switched OFF, the relay contacts are closed which turns ON the LED indicating lamp. When the MCCB is reset and switched ON, the indicating lamp switches OFF. Signal light shall be arranged to avoid damages while handling the MCCB enclosure at site.

Note‐ Firm should have BEE leveling

606

Schedule-A

MANUFACTURER’S GUARANTEED TECHNICAL PARTICULARS

Transformer Rating: 25 KVA (AL Wound ) 11 / 0.433 KV THREE STAR RATING WITH METER PROTECTION BOX HAVING PROVISION OF SINGLE METER

S.

No. P A R T I C U L A R S 25 KVA

1. Manufacturer’s Name and Address

2. Service (Outdoor, continuously rated)

3. Type (CRGO / Conventional)

4. Continuous max. Rating under peak ambient temp. of 50 ° C

5. Rated voltage : (a) H V

(b) L V

6. Rated current (a) H V

(b) L V

7. Rated Frequency

8. No. of phases

9. Method of connection : (a) H V

(b) L V

10. Vector group reference

11. Method of cooling

12. Max. temperature rise obtained by the transformer when run at the maximum ambient temp. of 50 ° C

(a) Of top oil by thermometer

607

S. No.

P A R T I C U L A R S 25 KVA

(b) Of winding by resistance

13. Hottest spot temperature, at rated current and voltage, calculated corresponding to the yearly weighted average ambient temp. of 35 ° C

14. Total Load losses (Watts) at 75 Deg.C. at 50% loading (Max).

15. Total Load losses (Watts) at 75 Deg.C. at 100% loading (Max.).

16.

Percentage impedance at full loadand at 75 ° C

17. Percentage resistance at full load and at 75 ° C

18 Percentage reactance at full load

19. Efficiency at 75 ° C :-

a) At unity power factor :-

i) At 125% of full load

ii) At 100% of full load iii) At 75% of full load

iv) At 50% of full load

v) At 25% of full load

b)At 0.8 power factor :-





20. Maximum efficiency

21. Load at which maximum efficiency occurs

608

S. No.


22. % regulation at full load & at 75 ° C:

a)At unity power factor

b)At 0.8 power factor

23. Max. flux density at rated voltage and rated frequency

24. Percentage no load current at rated frequency (without any positive tolerance)

a) At rated voltage b) At 112.5% rated voltage

25. Insulation level of transformer :- a) Impulse strength of HV

b) Power frequency withstand voltage

HV

LV

26. H V Bushing details:- (a) Rating of the bushing

(b) Impulse strength

(c) Power frequency withstand

voltage, dry and wet

(d) IS reference

27. LV Bushing details :- (a) Rating of the bushing

(b) Power frequency withstand

Voltage, dry and wet

(c) IS reference

28 Core Details a) type of core b) Grade

609

S. No.


c) Thickness d) Core Dia e) Effective Core Area, taking stacking

factor as 0.97 f) Centre distance between limbs

Window height

29. H V coil constructional details:- (a) type of winding

(b)No. of coils per phase

(c)Conductor cross Section(min.)

(d)Bare conductor dia

(e)Covered conductor dia

(f)`Phase current (H V)

(g)Current density

(h)Coil I. D

(i)Coil O.D

(j)Coil axial length (k) Total no. of turns per phase

(l) Resistance per ph. at 75 ° C

(m) Weight of covered conductor per

transformer (n) Inter layer insulation

(0) No. of vertical spacers per circle (in the annular gap between LV & HV)

30. LV coil constructional details:- (a) type of winding


(c) Conductor cross section(min.)

(d)Bare conductor size

(e)No. of conductors in parallel

610

S. No.


(f)Covered conductor size

(g)Phase current ( L V )

(h)Current density

(i) Coil I. D. (j) Coil O.D.

(k) Coil axial length

(l) Total no. of turns per phase

(m) Resistance per phase at 75 ° C

(n) Weight of covered conductor per transformer

(o) Inter layer insulation (p) No. of vertical spacers per circle

31. Minimum external clearances in air (with B M C s mounted)

(a) HV phase to phase (b) HV phase to earth

(c) LV phase to phase

(d) LV phase to earth

32. Minimum internal clearances (in oil) (a) Between HT outside surface and tank inside (non bushing side)

(b) Between HT outside surface & tank inside ( HV & LV bushing side)

(c) Between HV windings and yokes (end insulation)

(d )LV windings & yokes (e) ) From top of yoke to inside of top cover of tank (with gasket)

(f) LT / HT coil annular gap. (bare Conductor)

611

S. No.


(g) Radial clearance between core &

LV coil (Bare conductor)

(h) Phase to phase Clearance between Limbs (HV Conductors), with a minimum of 2 Nos. x 1mm Press board covering the tie rods

(i) Minimum thickness of locking Spacers between HV coil sections (including 1 mm ring of press board)

(j) Maximum clearance of core

channels from tank walls at each end

33. Tank details :- (a) Clear inside tank dimensions:

(i) Length

(ii) Breadth

(iii) Height

(b) Tank sheet thickness

(i) Sides

(ii) op

(iii) Bottom

(c) Tank stiffener details

(i) No. of stiffeners around

the tank (ii) Size

34. Cooling radiator details : (a) Cooling tube size

(b) Total length of tubes used

(c) Whether cooling calculations

612

S. No.


attached? (d) No. of tubes on each side

35. Core Details

(i) Tie rod details

(ii) Size of core frame channels

(iii) Core diameter (mm)

(iv) Core stud details

(v) Core coil assembly base supports

( 2 Nos )

(vi) Window Height (mm)

(vii) Limb Center (mm)

36. Transformer weight details:

(a) Core coil assembly

(b) Tank with fittings

(c) Oil weight

(d) Total weight of transformer

(e) Volume of oil (minimum

quantity for first filling)

37. Overall dimensions

(a) Length

(b) Breadth

(C )Height

38. Whether the bidder is an ISO : 9001 / 9002 certified company?

613

S. No.


39. MCCB

1. Rated current

2. Rated voltage 3. Fixed overload release

setting(Amp) 4. No.of poles 5. Rated short Ckt. Breaking capacity

(KA) is equal to ultimate breaking capacity as per IS 13947/1993

6. Power factor for short ckt.(max.) 7. Utilisation Capicity 8. Type of MCCB 9. Make

40. Metering protection unit a) Total chambers b) Size of enclosure (L X B X H) c) Min. clearance (Outgoing circuit)

i) Phase to phase

ii) ) Phase to earth d) Size Copper PVC wire e) Terminal Block details

i) Nos.

ii) Rating f) Toughened / Triplex Glass

g) Cable holding gland provided (Yes / No)

Size of earthing studs

(Signature)

Name & Designation with seal of the bidder

614

TECHNICAL SPECIFICATION FOR SUPPLY OF 11/0.433KV, 63 KVA & 100 KVA RATING OUTDOOR TYPE THREE STAR RATING ALUMINIUM WOUND DISTRIBUTION TRANSFORMERS.

1. SCOPE:

This specification covers the design, engineering, manufacture, assembly, inspection and testing at manufacturer’s works before supply of Oil immersed, Oil Natural Air Natural (ONAN) outdoor type Three Star Rating 11KV/433 V, three phase, 50 Hz, double wound core type, outdoor Type, Aluminium Wound Distribution Transformers of 63 KVA & 100 KVA ratings, complete with fittings and accessories for use in Distribution System.

1.1 The Equipment Offered shall be complete with all parts necessary for their effective

and trouble free operation. Such parts will be deemed to be within the scope of the supply irrespective of whether they are specifically indicated in the commercial order or not.

1.1.1 It is not the intent to specify herein complete details of design and construction. The equipment offered shall conform to the relevant standards and be of high quality, sturdy, robust and of good design and workmanship complete in all respects and capable to perform continuous and satisfactory operations in the actual service conditions at site and shall have sufficiently long life in service as per statutory requirements. In actual practice, not withstanding any anomalies, discrepancies, omissions, incompleteness, etc. in these specifications and attached drawings, the design and constructional aspects, including materials and dimensions, will be subject to good engineering practice in conformity with the required quality of the product, and to such tolerances, allowances and requirements for clearances etc. as are necessary by virtue of various stipulation in that respect in the relevant Indian Standards, IEC standards, I.E. Rules, I.E Act and other statutory provisions.

1.2 The Tender / supplier shall bind himself to abide by these considerations to the satisfaction of the Purchaser and will be required to adjust such details at no extra cost to the purchaser over and above the tendered rates and prices.


615



Note: Wherever ISS are mentioned, equivalent or better International standards are also acceptable.

IS: 1180 (PART-I)/2014: Specifications for outdoor type oil immersed distribution transformers upto and including 2500 KVA, 33 KV Class.

IS:2026 (PART-I,II,III,IV & V)/1981 – Power Transformers

IS:6600/1978 : Guide for loading of oil immersed Transformers

IS:335/1983 : New insulation oils for Transformers

IS:3347 (Part-I/Sec. 1 & 2) : Dimension of Porcelain parts & Metal parts for Transformer bushing (1.1 KV).

IS:3347 (PART-III/Sec-1 & 2) : Dimensions of Porcelain parts & Metal parts for

Transformer bushing (17.5 KV). IS:7421 : Porcelain Transformer Bushings for low voltage – upto 1 KV.

IS:2099/1986 : Porcelain Transformer bushing for AC volts above 1000 volts.

IS:3639/1966 : Fittings & accessories for Transformers

IS:1866/1978 : Code of practice for maintenance & supervision of insulating oil in service.

IS:5484 : Specifications for Aluminium wire rods.

IS:9335 : Specifications for insulating kraft paper. IS:1576 : Specifications for solid insulating press Boards for electrical purposes.

IS:6162 : (Part I) : Specification for paper covered Aluminium round conductors

IS:6162 : (Part II) : Specification for paper covered Aluminium rectangular conductors

IS:104 : Ready mixed paint, brushing zinc chromate, painting

IS:649 : Testing of steel sheets and strips for magnetic circuits.

616

IS:2362 : Determination of water content in oil for porcelain bushing transformers.

IS: 4257: Dimensions for clamping arrangements for bushings.

IS 6160 : Rectangular conductor for electrical machines.

IS:10028 : Selection, Installation and maintenance of transformers IS: 3401 : Silicagel

IS: 5/1961: Colour for ready mixed paints REC Specification No. 2 REC Specification No. 39/1993 CEA Specification, Chapter 4

Material conforming to other internationally accepted standards, which ensure equal

or better quality than the standards mentioned above would also be acceptable. In case the Bidders who wish to offer material conforming to the other standards, salient points of difference between the standards adopted and the specific standards shall be clearly brought out in relevant schedule. Four copies of such standards with authentic English Translations shall be furnished along with the offer.



i) Peak ambient temperature : 50°C ii) Minimum Ambient Temperature in shade : -5°C iii) Maximum average ambient temp. in a 24 hours period in shade : 45°C iv) Maximum yearly weighted average ambient temperature : 35°C v) Maximum temperature attainable by an object exposed to sun : 60°C vi) Maximum relative humidity : 100 % vii) Average number of thunder storm days per annum : 40 viii) Average number of rainy days per annum : 120 ix) Average annual rainfall : 15-100 cm x) Number of months of tropical monsoon conditions : 4 Months xi) Maximum wind pressure : 195 Kg/mt² xii) Altitudes : Not exceeding

1000 mtrs. The equipment shall be for use in moderately hot and humid tropical climate,


4. PRINCIPAL PARAMETERS:

617

The Transformers shall be suitable for outdoor installation with three phase 50 Hz 11 KV system in which the neutral is effectively earthed and should be suitable for outdoor service as step down transformers under fluctuations in supply voltage upto plus 12.5% to minus (-) 12.5% permissible under Indian Electricity Act and rules there under.


i) Continuous rated capacity : 63 KVA & 100 KVA



iv) Rated LT voltage : 433 V (P-P) / 250 V (P-N)

v) Frequency : 50 Hz ± 5%

vi) No. pf phases : THREE

vii) Primary connection (HT) : DELTA

viii) Secondary connection (LT) : STAR

ix) Vector Group : Dyn-11

x) Percentage impedance at 75°C : 4.5 %

xi) Taps (off circuits) : TAPS ARE NOT REQUIRED.

xii) Type of cooling : ON AN

xiii) Fault level of the system : 750 MVA


The transformers shall be designed and constructed to withstand without damage the

thermal and dynamic stresses of an external short circuit. The manufacturer / supplier shall furnish all relevant design data and calculations in support of having fulfilled this requirement as stipulated in IS:2026 (Part-I)

618



6.1 The bidder shall guarantee individually the no-load loss and load loss without any positive tolerance. The bidder shall also guarantee the total losses (no load + load lossesat 75 0C) at the 50% of rated load and total losses at 100% of rated shall not exceed the maximum total loss values given in Table-9 of IS 1180(Part-1):2014.

6.2 The maximum allowable losses at rated voltage and rated frequency

permitted at 75 0C for 11/0.433 kV transformers can be chosen by the utility as per Table-9 for ratings 5,10, 16, 25kVA as per Energy Efficiency Level-2 specified in IS 1180 (Part-1): 2014 for single phase distribution transformers.

6.3 The above losses are maximum allowable and there would not be any

positive tolerance. Bids with higher losses than the above specified values would be treated as non-responsive.

Note:- The Distribution Transformers shall be BIS certified in line with electrical transformers (quality control) order,2015(along with its latest amendments) issued by Department of heavy industries,Ministry of heavy industries & public Enterprises, Govt. of India.

7. TEMPERATURE RISE:

Each transformer shall be capable of operating continuously at its normal rating without exceeding following temperature rise with the above service conditions given in clause-3.

i) 35 Deg. C in oil by thermometer. ii) 40 Deg. C in winding by resistance


The transformer shall be capable of giving continuous rated output without exceeding the specified temperature rise.

The Hot spot temperature at annual weighted average ambient temperature of 35o C shall not exceed 98o C, when calculated as per IS: 2026 ( Part-II)

619

However, the transformer shall be designed for class ‘A’ insulation



9. IMPEDANCE:

The percentage impedance at rated current and at 75°C shall be 4.5% with plus/minus (+/-) 10% tolerance.

10. TAPPINGS: No taps are to be provided in these transformers.

11. FREQUENCY:

Transformers shall be designed for normal frequency of 50 Hz, but shall be capable of giving the rated output with the variation of plus/minus (+/-) 5% from the rated frequency.

12. ELECTRICAL CLEARANCES:





11000 Volt A I R 255 mm 140 mm



620


PARTICULARS 63KVA & 100 KVA

a) On width side (non bushing side) 25 mm

b) On length side (bushing side HV & LV both) 40 mm

c) Between HV windings & yokes (end insulation) 20 mm

d) Between LV windings to core (Bare conductor) 3.5 mm

e) From top of yoke to inside of top cover of tank (with gasket) 75 mm

f) Between LT/HT winding (Radial bare conductor Clearance) 11 mm

g) Phase to Phase Clearance between HV limbs 10 mm


13. TEST VOLTAGE:


Nominal system Highest system Impulse withstand Power frequency test

Voltage (RMS) voltage (RMS) voltage voltage in (RMS)

11 KV 12 KV 95 KV (PEAK) 28KV

0.433 KV ---- ---- 3 KV




621


The radiator tubes shall be arranged in two equal banks fixed at two opposite non bushing sides. The header pipe connecting radiator bank to the tank shall be rectangular in shape with approximate size of 100x20 mm. Alternatively round pipe of dia 32 mm can also be used for connecting the radiator bank to the tank. The placement of top header pipe to the tank body shall be above the top of yoke, to facilitate cooling for hot oil sump over top yoke.

Cooling area of the tank/radiators should be sufficient to dissipate the guaranteed losses satisfactorily. Necessary calculations in this regard shall be furnished by the Bidder with their tender. For the purpose of heat dissipation calculations, the following criteria shall be adopted:



ii) Elliptical tube of section 57 -- 55 watts/meter length.

Note- The provision of radiator is essential in distribution transformers to be supplied against this tender.

15. WINDING AND INSULATION:

i) MATERIALS:

Double paper covered aluminium conductors shall be used for 11 KV class transformers of 63 KVA & 100 KVA rating. The covering shall conform to IS:6162 (part I & II).

ii) CONSTRUCTION:

622


For phase barrier, 2 Nos. of 1 mm thick press board shall be used for covering the tie rods. Besides, tie rods shall be covered by SRBP tubes of suitable size.

2 mm press board shall be used for base support insulation and core clamping channel insulation.

For bottom and top yoke insulation, only PC Board of min. 2 mm thickness will be used.

Also, vertical spacers between HV and LV coils and radial spacers (tickleys)/ blocks etc. shall be of PC Board only.



Min. number of coils on HV side shall be 4 (four) per phase for 63 KVA & 100 KVA rating transformers. Dovetailed shaped radial spacers shall be placed between HV coil sections, suitably – locked with vertical spacers around the circumference of the coils. The number of such spacers shall be minimum 4(four).

Current Density


623

Rating Current density in Amp/mm .sq.


63 KVA 1.6 1.6

100 KVA 1.6 1.6

iii) INSULATION MATERIAL :



B) HV Winding: The following method shall be adopted for taking out HV connections- a) The coil series connections shall be made by soldering / brazing only, after completely

removing the insulation from the ends.

b) Starting and finishing leads of HT coils shall be covered with empire sleeve(s) of size. These leads should be clamped with the body of the winding with the help of cotton twine during manufacture of the coils.

c) All delta leads from the HT coils as well as HT line leads shall be taken out through multiple paper covered (MPC) copper wires of sufficient cross section area to impart the desired mechanical strength. The current density in HV lead wire shall not exceed 0.8 A/mm². These lead wires shall be provided with multi layer paper insulation of minimum 1.0 mm thickness i.e. minimum increase in diameter due to paper insulation shall not be less than 2 mm. The layer of glass sleeves/ glass tape shall also be provided on the delta MPC wire and it should be further covered with minimum 12 mm dia SRBP tube. The MPC should also be varnish dipped. The SRBP tube shall be extended in such a way that it is entered upto 50% of bushing height.

d) All the above leads shall then be clamped tightly with cotton twine directly on to the special frame/bracket making “Pie” shape connection. This structure could be made up of Bakelite/

624

Permalli wood/ laminated PC board flats, having minimum thickness of 6 mm. Line leads leading to the HV bushing terminals shall be directly clamped to the horizontal support bar of the “Pie” structure so that any tension which may develop in the HT leads due to jerks or at the time of making the connection , is not passed to the HT coils.

e) Delta joint and lead from delta joint to bushing rod shall be made by brazing only.

B) LV Winding :

a) The LV connection shall be taken out by cut on the top yoke channel duly reinforced to compensate for the mechanical strength.

b) The layers in LT Coil may be either even or odd in numbers but minimum layers shall be two.

c) LV star point shall be formed of aluminium flat of sufficient strength. Leads from winding shall be connected to the flat by brazing.

d) Firm connection of LT winding to bushing shall be made of adequate size of “ L shape flat”. Connection of LT coils to L shape flat shall be by brazing only.


f) Neutral of the Secondary winding (LV) shall be brought out to a separate insulated

bushing.

g) For Aluminium windings, L&T, ALKAPEE Aluminium brazing rods with suitable flux will be used.

16. CORE CONSTRUCTION & CORE COIL ASSEMBLY DETAILS: A. CRGO CORE (i) The core shall be stack/ wound type of high grade cold rolled grain oriented steel

laminations, having low loss and good grain properties, coated with hot oil proof insulation, bolted together to the frames firmly to prevent vibration or noise. All core clamping bolts shall be effectively insulated. The complete design of core must ensure the permanency of the core losses with continuous working of the transformers. The value of the flux density allowed in the designs and grade of laminations used shall be clearly stated in the offer, along with the curves. The transformer core shall be constructed out of the prime class of materials. CRGO Lamination used shall be of prime grade and not second grade steel laminations.

625


(ii) It will be mandatory for all the transformer manufacturers to use only PRIME grade CRGO Laminations with specific loss of 0.89 watt per kg. at 1.5 Tesla or any other combination of better grades with any thickness subject to maximum specific loss of 0.89 watt per kg. at 1.5 Tesla will also be acceptable. The bidder shall furnish the core loss (watt/Kg.) and power (VA/Kg) curves of the laminations used. The core shall be properly stress relieved by annealing in inert atmosphere. The transformer shall be suitable for over fluxing (due to combined effect of voltage and frequency) upto 12.5% without injurious heating. The operating flux density shall be such that there is a clear safe margin over the fluxing limit of 12.5%.

(iii) Full mitred core construction technique shall be adopted. Top yoke & bottom yoke

pieces shall all be in one single piece and no cut pieces shall be acceptable. The cross sectional area of yoke & limb shall be approximately same.

(iv) The transformer core shall not get saturated for any value of V/f ratio to the extent of 115% of the rated value of V/f ratio (i.e. 11000/ 50) due to combined effect of voltage and frequency without injurious heating at full load conditions. The bidder shall furnish necessary design data in support of this situation.

(v) Flux density at rated voltage and frequency of core and yoke shall not be

more than 1.60 Tesla. The Over fluxing shall be limited to 12.5% of rated value and flux density at 112.5% of rated voltage does not exceed by 1.9 Tesla.

The No Load Current (magnetising current) at rated voltage and at 112.5% of rated voltage shall not exceed the values given below:

At 100% rated voltage At 112.5% rated voltage

63 KVA 3% 6%

100 KVA 3% 6%

The tolerance on magnetizing current shall be +30% on declared value of magnetizing current as per IS: 2026.

Vi) Core clamping :

a) MS Channel of 100 X 50 mm min. size shall be used on top and bottom (for stacked core transformers).

626

b) 2 x 12 mm high tensile bolts to be used in parallel at each end. c) Channel on LV side to be reinforced at equidistance, if holes/cutting is done for LT

lead in order to avoid bending of channel. d) MS channel shall be painted with varnish or oil-resistant paint. e) Tie-rods : 4 Nos. of M12 M.S steel rods shall be effectively insulated. f) All top and bottom yoke nuts & bolts and tie rods shall be painted with oil and corrosion-resistant paint and phosphate coated paint for tie rods before use. g) Only prime quality CRGO sheets should be used in the transformers and no Second/Defective/ Scrap CRGO finds way into transformers.

B. AMORPHOUS METAL:

a) The core shall be high quality amorphous ribbons having very low loss formed into wound cores of rectangular shape, bolted together to the frames firmly to prevent vibration or noise. The complete design of core must ensure permanency of the core loss with continuous working of the transformers. The value of the flux density allowed in the design shall be clearly stated in the offer. Curve showing the properties of the metal shall be attached with the offer.

b) Core Clamping – Amorphous Metal and CRGO wound core Transformers 1. Core clamping shall be with top and bottom U-shaped core clamps made of sheet

steel clamped with MS tie rods for efficient clamping.

2. MS core clamps shall be painted with varnish or hot oil resistant paint 3. Suitable provision shall be made in the bottom core clamp / bottom plate of the

transformer to Arrest movement of the active part.


d) density should not be more than 1.6 Tesla for Amorphous core. No load current not exceed 3% of full load current and will be measured by energizing the transformer at 433 volts 50 c/s on the secondary. Increase of voltage of 433 volts by 12.5% shall not increase the no load current disproportionately high and shall not exceed i.e., 6%. Test for magnetic balance by connecting the LV phase by phase to rated phase voltage and measurement of an, bn, cn voltage will becarried out.

627


C. CORE-COIL ASSEMBLY:


For top yoke channels, if cut or holes are made for taking LV connections, suitable reinforcement to channels shall be made by providing adequate size of MS Flat of the thickness not less than 6 mm.

On the core-coil assembly, core clamping channels, tie rods, core studs, spacers, assembly base supports, etc. shall be provided as per details given hereunder:

Sr. No.

Item Particulars


b) Core studs Minimum 4 Nos. of 2X12 mm each properly insulated and covered with SRBP tubes. The core studs shall also be provided with lock nuts.



2 Nos. MS channels OF 100X50 mm., with minimum peripheral coverage of 40%.


4 MS Channels of 100X50 mm size (applicable for CRGO transformers)


628

The assembly fixing boss nut(s) are to be welded,20-30 mm off the center line (and diagonally) of the tanks, so that assembly shifting during transport etc. is prevented. M S Channel, Tie Rods etc should be painted with hot oil and corrosion resistant paint before use.

All core-coil assembly shall be indelibly marked / punched on core channel / a identity plate

welded on core channel with following details:

1. Name of Supplier: 2. IPDS/ TN No:

3. Rating:

4. Sr. No. of Transformer:

In case if above marking is not found on the core assembly of physically opened

transformer selected for physical verification during final inspection then no further inspection shall be carried out and re-inspection charges shall be payable by the supplier.

17. TRANSFORMER TANK: (a) Transformer tank shall be rectangular in shape, robust in construction and with adequate strength to withstand the pressures developed at the time of severe fault conditions. The tank body shall be suitably stiffened to achieve the object. The tank sheet shall be electrically welded both from inside and outside to impart proper mechanical strength and to plug leakage of oil. All joints of tank and fittings shall be oil tight and no bulging shall occur during service. The tank design shall be such that the core and windings can be lifted freely. The tank plates shall be of such strength that the complete transformer when filled with oil may be lifted bodily by means of lifting lugs provided. The stiffeners shall be welded full length. All the welding shall be continuous. The top cover plate shall be sloping down by more than 15 mm, opposite LV bushings side. The top cover shall be extended by 5 mm by all the sides beyond the flange of the top cover. Accordingly length of the lifting hooks shall be extended. The top cover shall have no cut at point of lifting lug. No negative tolerance in the tank dimensions is acceptable in actual supply. The tank shall be fabricated by welding at corners. No horizontal or vertical joints in tank side walls and its bottom and top cover will be allowed.

(b) (i) Minimum size of MS Sections to be used in construction of transformer tanks shall be as under:

Sr. I T E M S 63/ 100 KVA

629

No.






6 No. of stiffeners (To be welded with one face while the other side of the angle forms inverted “L”)

1



9 Cover Bolt Size M10/ 3/8 x 1.5”



8t mm flat

12 Tank Base Channel (ISMC Type) 2 ( 100 x 50 mm)

NOTE: Each cover bolt shall be complete with two flat washers, one nut and one spring washer. The 12 Nos. Nut Bolts (4 Nos. each on length side and 2 Nos. each on width sides of the tank body) to be tag welded on the top cover/ tank body of the transformer.

The 04 Nos. Anti Theft Fasteners shall be provided - one each on all four sides in centre of

body of transformer.

Two holes shall be provided – one on top cover and other on collar of transformer to facilitate providing of 2 Nos. poly-carbonate seals on longitudinal side.

The supplier shall provide additional 8 Nos. stainless steel anti theft fasteners (nuts and bolts) for fixing the base channel on structure.


(b) (ii) MEASUREMENT OF SHEET THICKNESS OF TRANSFORMER TANK

630





3. Side Wall(s) On all four sides

(average is to be taken)



··· Sheet thickness of transformer tank as per relevant tender specification is as under for ready reference:

Sr. No.

Rating Top Cover (mm) Bottom Cover (mm)

Side of Tank

(mm)

1 63 KVA Three Phase 5.0 5.0 3.15

2 100 KVA Three Phase 5.0 5.0 3.15

Further it is also intimated that 5% variation beyond tolerance limit in measurement of sheet thickness on negative side shall be acceptable by the Discom with levy of penalty. The rate of penalty will be Rs.80.00 per Kg.

For example:

631

Weight of 25 KVA Transformer Tank 120 Kg. (approx.)

Variation in thickness of tank 5% (beyond tolerance limit)


-------------

100

In case any dimension in transformer tank sheet thickness found beyond aforesaid limit of 5% will not be acceptable to the Discom and the relevant sub-lot shall stand rejected and the lot of such transformers will have to be replaced by the firm.

Transformer having thickness even more than 5% after allowing rolling tolerance shall be

acceptable.

The highest percentage variation on negative side in respect of measurement of sheet thickness of any part of tank will be applicable on the entire dimensions for levy of penalty.


(c ) Lifting Lugs: Two Nos. welded heavy duty lifting lugs of MS plate of 8 mm thickness, suitably reinforced by vertical supporting flat welded edge wise below the lug on side wall shall be provided, these shall be so extended that cutting of bent plate is not required


(i) The gasket provided in between top cover plate and tank shall be of min. 6 mm thick

neoprene rubberized oil resistant cork sheets conforming to type B or C as per IS 4253 part II

(ii) G.I. Nut bolts shall be of size M 10 x 40 mm / 3/8x1.5” long with two flat washers, suitably

paced (as specified) to press the cover. (iii) Height of the tank shall be such that minimum clear height of 75 mm is achieved between

top of yoke and under side of the tank cover (with gasket in place). (iv) All steel screws, nuts and fasteners exposed to atmosphere shall be either galvanised or

cadmium plated or electroplated.

(v) All sealing washers / gaskets shall be made of oil and heat resistant neoprene or

nitrile rubber. Gaskets made of natural rubber sheet are not permissible. The

632

minimum thickness of gaskets shall not be less than 6 mm for tank cover and 4mm for HT/LT gasket washers.

vi) New cork/ Talbros make neoprene/nitrile based rubberized cork sheet – grade RC-70-C shall only be used as gasket material. Alternatively, other makes of gaskets having type designations as under can also be used, if ‘Talbros’ make gasket is not available:

S. No. Name of the firm Commercial name of gasket manufactured by the firm.

1. M/s. Nu-Cork Products P. Ltd. Gurgaon Nu-Cork (Neoprene) Nu-Cork 999 RC-70-C

2. M/s. Bharat Corrub Ind. Vadodara

Chetak (Neoprene) RC-70-C

3. M/s. Grindbeck. Gujarat Zebra (Neoprene) RC-70-C

4. M/s Goodwill Rubber Ind. (P) Ltd., Calcutta. Mayur (Neoprene) RC-70C

(e) Tank shall be reinforced by continuously welded angle on all the four sides of the walls, on the edge of tank, as specified above. The permanent deflection shall not be more than 5 mm upto 750 mm length and 6.5 mm upto 1250 mm length when transformer tank without oil is subjected to the vacuum of 250 mm of Mercury.


Steel surface shall be prepared by sand / shot blast or chemical cleaning including phospating, as per IS 3618. Heat resistance paint (Hot oil proof) shall be provided inside tank. On external surface, one coat of thermo-setting powder paint or 2 coat of Zinc chromate followed by two coat of olive green colour conforming to Shade No. 220 of IS –5 of 1961 in order to distinguish of star level transformers, shall be applied.




Inside

Outside

01 01

LIQUID PAINT

633

a) Zinc Chromate (Primer) Outside 02

b)synthetic Enamel (finish coat) Outside 02

c) Hot Oil Paint

Inside 01


g) The IPDS/TN No., Sr. No. of the transformer and name of the manufacturer should be punched/ embossed on top cover/ bottom cover/ sides of tank body (size of letter 10x5 mm).

18. FITTINGS & ACCESSORIES:

The following standard fittings shall be provided on each transformer: m) Earthing terminals of M10/ 3/8x1.5” with tinned lugs and symbol – (2 Nos.) n) Lifting lugs – (2 Nos. for main tank). o) Rating and terminal marking plate (non-detachable), details to be included


clearly marked - (1 No.) p) Bi-metallic terminal connectors on HV bushings and it may be ensured that connectors shall be

fitted before dispatch. q) Oil level gauge of minimum 150 mm length of prismatic glass, indicating three positions of oil,

marked as follows, shall be provided:

1) -5 °C - Min.

2) 30 °C - Nor.

3) 98 °C – Max.

r) Silica Gel Breather shall be aluminium/ metal – (1 No.) s) Thermometer pocket, 12.5 mm dia with cap. shall be provided –– (1 No.)

t) HV Bushings. These shall be of 17.5 KV/250 A class, with non adjustable, single gap type

arcing horns – (3 Nos.) u) LV Bushings. 1.1 KV class, 250A (M12 stem) – (4 Nos.)

634

v) Under carriage: For transformers of 63 KVA & 100 KVA rating shall conform to REC specifications.

w) Brass rod 12 mm diameter for HT – (3 Nos.) x) Brass rod 12 mm diameter for LT – (4 Nos.)

Note: LV/ HV Connector shall not be the integral part of the bushing stems.

19. CONSERVATOR:


conservator. In addition, the cover of the main tank shall be provided with a self-sealing pressure release device designed to operate at minimum pressure of 8 PSI (0.564 Kg./cm. Sq.) to enable release of air trapped within the main tank, unless the conservator is so located as to eliminate the possibility of air being trapped within the main tank. The conservator shall be of cylindrical shape and it should be provided above the HV bushing with a minimum clearance of 50 mm and suitably inclined to maintain the clearance.

The total inner volume of conservator shall be minimum 15 Liter for 63 KVA & 18 Liter for 100 KVA transformer. The inside diameter of the pipe connecting the conservator to a main tank shall be min. of 30 mm and it should be projected into conservator in such a way that its end is approximately 25 mm above the bottom of conservator so as to create a sump for collection of impurities. The min. oil level (corresponding to – 5 deg. C.) should be above the sump level. The connecting pipe from conservator tank to main tank shall have a sloping flap so that oil falling from pipe shall not fall directly on the active job.

Apart from the features specified in this clause for conservator tank, the oil filling hole cap of conservator shall be welded with tank body with the help of suitable inverted ‘U’ shape clamp.


Body of breather shall be of aluminium/ metal and inside container for Silica gel shall

be of tin sheet. The breather shall be only from reputed and approved manufacturer and as per the approved drawing. The gel capacity shall be of 250 grams. Inverted U shape pipe shall be used for breather. Mounting arrangement of the breather shall be flanged/ threaded type as per details given in the illustrative drawing attached.

The design shall be such that the condition of Silica gel is clearly visible from a distance, even after years of service.

21. H V BUSHING TERMINAL DETAILS :

The transformer shall be provided with outdoor type 3 Nos. 17.5 KV /250A class porcelain bushings, conforming to IS:3347/1972 & IS:2099/1973 from the manufacturer of repute. The LV/ HV bushings shall be on the opposite side of the tank. The bushing on the top cover of the transformer shall not be acceptable.

635

The bushings rods and nuts shall be made of brass. The HV bushing shall be fitted on a conical pocket (full length tank) on the tank body and not directly on the pipe/ flange. However, small pieces of pipe may be mounted on conical pocket for maintaining electrical clearance if required. The inner porcelain portion of the bushing shall be projected about 50% of the length inside the conical pocket. HT bushing(s) mounting bolts should be tag welded.


The arcing horn(s) shall be single gap and fixed type. HV bushings shall be of reputed make such as BEPCO, JAYSHREE, WSI, SESHASAYEE, JAIPUR GLASS, BPPL Bikaner, Agarwal salt Co. Bikaner, Bais Sanitary Works, Bikaner/KRISHNA CERAMICS, NASIRABAD or any other make - approved by the purchaser. The HV bushings shall generally conform to IS: 3347 and IS: 2099. Embossing showing the manufacturer’s name and month & year of manufacture shall be clearly visible on HV bushings, even after fixing on transformer(s).

As mentioned earlier, suitable bi-metallic connectors shall be provided, forming an integral part of the bushing stem, having capacity of about 1.5 times the rated current of the transformer.

22. L V BUSHING TERMINAL DETAILS:

LV Bushing side shall be opposite to the HV Bushing side. 4 Nos. LV Bushings (1.1 KV/ 250 A) shall be mounted on a special pocket on the tank wall. Projection of the LV pocket shall be such that inner portion of the LV stem shall not project more than 20 mm inside the tank, to facilitate unhindered lifting of the core coil assembly. Bushing stem of M12 size shall be of brass. Rest of the components shall conform to the requirement of IS:3347 (Part I/section 2). The LV bushings shall be of reputed make such as JSI, JAIPUR GLASS, BPPL Bikaner, Baid Sanitary Works, Bikaner, Agarwal salt Co. Bikaner, or any other make approved by the purchaser. The LV bushings shall generally conform to IS: 3347 and IS: 7421.


636


The make of Transformer Oil shall be either APAR/SAVITA/ RAJ LUBRICANTS/ ANAMIKA/SHARAVATI/ MADRAS PETRO/ RAJ PETROL/ LUBRICHEM, MUMBAI/ OPANAMA PETROCHEM, ANKELSHWAR/ TASHKENT OIL, VADODARA/COLUMBIA. The transformer oil sample taken from the transformer shall be subject to testing as per provisions ofIS:1866.


24. IDENTIFICATION DETAILS:

a) Rating & terminal marking plate: Each Transformer shall be provided with non detachable name, rating and terminal marking plate fitted in a visible position. All details shall be given on one plate. Material of the plate shall be stainless steel only. Thickness shall be 0.9 mm (with a tolerance of ±0.1 mm). The plate shall be made absolutely undetectable either through welding or riveting or through any other approved method.



(i) P.O No.. - month & year.

(ii) IPDS/TN No.

637

(iii) Sr. No. of transformer.

(iv) Date of despatch - month & year

(v) Date of expiry of guarantee period – month & year

(vi) Maximum Guaranteed No Load & Load Loss Figures (vii) Recommended fuse sizes for HV & LV sides. viii) Name & Full address of the manufacturer.

(ix) Capacity of the transformer. (x) Rating of the transformer. (xi) Type – Oil filled naturally cooled.


b) Identity Plate :- A M.S. plate of size 75 x 75 x 2.5 mm shall be continuously welded to

the main tank body below the middle HV bushing and in clearly visible position, with following details clearly punched :

JAIPUR DISCOM IPDS/TN –

……… KVA , S.NO. ……….

……….MAKE ……………. c) Identification Mark :- In addition to above, the following identifying details shall be

clearly punched on top cover near lifting lug, towards neutral side, with minimum 8 mm x 6 mm size punch letters.

MAKE

Sr. No.

The above identification mark shall also be punched / welded to one of the top core clamping channels.

Further following details is to be punched on all sides of the tank preferably in center. The dimensions of letters should be 10x10x1 mm. The punching shall be distinct and visible.

d) Make

IPDS/TN

638

e) IPDS/TN No. f) Sr.No.

(viii) Technical Plate- In addition to existing provision of identity plate and name plate one plate also be affixed on the transformer mentioning the following details:-

(a) Name of the Firm (b) IPDS/TN No. (c) Make (d) Rating (e) Core :-

1. Core Dia 2. Core Area

(f) LV Coil :- 1. ID/OD Dimensions 2. Conductor Size

(g) HV Coil :- 1. ID/OD Dimensions 2. Conductor Size

(h) Limb Centre (i) Window Hight

25. GUARANTEED AND OTHER TECHNICAL PARTICULARS FOR

TRANSFORMERS:

Guaranteed Technical particulars of the transformers offered shall be furnished in A-4 size paper by the Tenderer in the pro-forma appended herewith at Annexure-A. Complete details shall be furnished. Tolerances on weight quantity and dimension figures shall be ± 5%(except for internal configuration) at the tender stage, subject to maintaining the minimum electrical clearances as per the specification. However, no negative tolerance shall be allowed on the short circuit type tested design. Electrical performance data shall be subject to tolerances as per ISS, unless otherwise specified in this specification. However, the No Load loss and Load loss figures shall be maximum guaranteed without any positive tolerance.


The bidder shall furnish valid type test certificates of same rating of offered item from any CPRI / independent NABL Accredited laboratory/ Govt. approved lab. Such type test certificates should not be older than 5 years as on the date of opening of tender. For this purpose date of conducting type test will be considered. Type test conducted at supplier’s

639

own NABL accredited lab shall not be considered. The following type tests shall be conducted on one unit at NABL/ Govt. approved lab:

a) Lightening Impulse Voltage withstand test at 95 KVp.

b) Short Circuit Test.

c) Temperature Rise Test.

d) Air Pressure Test at 80 KPa for 30 minutes and vacuum of 250 mm of

mercury for 30 minutes for transformer upto 200 KVA rating and 80 KPa for 30 minutes and vacuum of 500 mm of mercury for 30 minutes for transformer above 200 KVA rating and upto including 2500 KVA rating as per IS:1180 Part-I:2014.


The supplier shall be accompanied with the following drawings / Calculation sheets, as per the offered designs. The drawings shall be only on A-3 (420 x 297 mm) size paper and calculation sheet shall be on A-4 size paper only.

a) rating / diagram plate drawing.

b) Outline and general arrangement drawing.

c) Core-coil assembly drawing. d) Core section (for limb and yoke) along with flux density calculation sheet /

drawing. e) Cooling area calculation sheet. f) Thermal Ability short circuit calculation sheet. G) Heat dissipation calculations (heat dissipation by tank walls excluding top and bottom

should be 500 W/sq.meter.

28. QUALITY ASSURANCE PLAN:


The supplier shall furnish the details of type tests conducted on the Transformers offered to supply

640

The tenderer should possess adequate facilities for inspection and testing of the Transformers, as per requirement of the relevant ISS and this specification. In case any supplier is found not having all the instruments/equipment required for testing, the offer shall be ignored. No borrowing of instruments / equipment shall be allowed. Testing of the Transformers shall also not be allowed at the works of any other manufacturer. However, testing may be allowed at any Government Testing Laboratory.

29. INSPECTION AND TESTING:

( i ) The inspection and testing shall be conducted at the place of manufacture.


( ii ) The supplier shall afford the inspector representing the purchaser all

reasonable facilities, without charge, to satisfy him that the material is being manufactured in accordance with the specification. The bidders must have adequate set of instruments for conducting testing as per ISS/ Specification. The instruments for measurement of losses shall be of accuracy class of 0.5 or better. The instruments shall be duly calibrated and Calibration Certificate should not be older than one year on the date of presentation to the Inspecting Officer. The calibration shall be arranged from NABL accredited testing house. A comprehensive list of testing equipment/ instruments indicating make, Sr.No., type, class of accuracy, calibrating agency, calibration date etc. should be furnished alongwith the bid. The calibrated instruments shall be duly sealed by calibrating agency to avoid any tampering with calibration and the details thereof shall be clearly mentioned in the Calibration Certificate(s).

( iii ) The supplier shall keep the purchaser informed in advance, about the

manufacturing programme so that arrangements can be made for inspection. The supplier shall give minimum fifteen days advance intimation to enable the purchaser to depute his authorised representative for inspection/ witnessing of various tests on the equipment/ material as detailed below:


30. ROUTINE/ ACCEPTANCE TESTS:

(A) 100% testing of the Distribution Transformers shall be carried out at firm’s works for measurement of total load losses at 50% & 100 % loading. Remaining testing shall also continue to be carried out as per practice.

641

(B) All the assembled/ finished transformers prior to dispatch shall be subjected to routine tests as per IS:2026. Minimum 25% of the offered lot size samples subject to minimum 5 Nos will be taken for routine and acceptance tests. The supplier shall invariably furnish manufacturer’s routine test certificate along with inspection call of the offered transformers for pre-dispatch inspection. The inspection offers without furnishing of routine test certificates as per ISS of all the transformers offered for final inspection shall not be entertained, and any delay on this account shall be to firm’s account.

The selected samples shall be subjected to the following routine/ acceptance tests at the manufacturer’s works in accordance with the relevant ISS:



3. Induced over voltage withstand test

4. Measurement of windings resistance cold (at or near the test bed temperature)


6. Measurement of Impedance voltage and load losses at rated current and normal frequency.


loading).

8. Measurement of No load current at 100 % and 112.5% of rated voltage and normal frequency.

9. Checking of rating and terminal marking plate.

10. Checking of weights , dimensions, fittings and accessories, tank sheet thickness, oil quantity ,




During final inspection, sheet thickness shall also be measured of the transformer opened for physical verification. The instrument for measurement of sheet thickness will be provided by the supplier.

642

12. Oil dielectric strength (break down voltage) test shall be carried out on the transformers opened for physical verification and average value shall be calculated.

13. Checking of manufacturer’s test certificates and invoices for major raw materials

shall be done and copies thereof duly signed by firm’s representatives and inspecting officers shall be enclosed with the inspection report.

Invoices of CRGO/ AMORPHOUS material shall be provided by the supplier to the

inspecting officer at the time of inspection and same shall be verified by the inspecting officer.


unit of 63 KVA & 100 KVA Transformers unit :

(i) Air pressure test on empty tank of transformer opened for physical verification test. (See note below)

(ii) Over Flux Density Test (in the first lot and may be repeated in subsequent lots if desired by purchaser).

(iii) Measurement of unbalance current. (iv) Magnetic Balance Test (See note below) (v) Oil Leakage Test (See note below)

Fifteen days clear notice shall be arranged for pre-despatch inspection by purchaser’s

representative as per General Conditions of Contract.

After successful inspection, the inspecting officer shall seal each and every transformer by sealing the transformer with 2 Nos. poly-carbonate seals on longitudinal side as per the manner mentioned in Clause No. 17 above. Before sealing, the inspecting officer will ensure that all the offered transformers are complete and duly fitted with name, rating and diagram plate, identification plate (on tank body & Top cover) as specified in this specification.

Also after inspection/ testing, inspecting officer(s) shall affix Signature

Seals also on each Transformer in addition to other seals (i) INSULATION RESISTANCE MEASUREMENT:


20

Deg.C. 30Deg.C.

40Deg.C

50Deg.C.

60 Deg.C.

11000 Volts (HV)

800 400 200 100 50

433 Volts (LV)

400 200 100 50 25

643

ii) AIR PRESSURE TEST:

This test shall be conducted as type test as per IS-1180 (Part-I)/2014. The pressure gauge and vacuum gauge shall be duly calibrated and sealed by an independent recognised test lab(s).

The test procedure shall be as detailed below :

The tank shall be fixed with a dummy cover with all fittings including bushings in

position and shall be subjected to air pressure of 80 kPa for 30 minutes and a vacuum of 250 mm of mercury for 30 minutes.

Permanent deflection of flat plate, after pressure has been released, shall not exceed

the values given below:

Length of plate up to Deflection

750 mm 751 to 1250 mm

5.0 mm 6.5 mm

iii) MAGNETIC BALANCE TEST:

This test shall be conducted as an additional test on one sample transformer from each lot offered for inspection.

The application of low voltage to the middle limb will induce approximately equal

voltages on the two end limbs. The application of voltage to the end limbs will induce greater voltage in the middle limb and less voltage in the other end limb. Uniformity of induced voltages shall confirm the healthiness of the transformer windings.

The procedure for the test shall be as under:

Apply 250 Volts between LV terminals-2u-2n and measure voltages between 2v-2n

& 2w –2n. Apply 250 Volts between 2v-2n and measure voltages between 2u-2n & 2w-2n.

Apply 250 Volts between 2w-2n and measure voltages between 2u-2n & 2v-2n.

The measured voltages shall satisfy the conditions detailed as above.

iv) OIL LEAKAGE TEST :

The oil leakage test shall be conducted on one unit selected from the offered lot of each rating. Transformer complete in all respects shall be subjected to the pressure corresponding to 0.5 Kg / cm² and maintained for three hours. No leakage should occur.

31. TYPE TESTS:

644

The firm shall furnish complete type test reports of this rating transformer ( submitted for BEE labeling ) for verification and checking along with drawings to be got approved later on.

32. RANDOM SELECTION AND TESTING (RST):

Measurement of total losses (at 50% & 100% loading):

(i) After pre-dispatch inspection of material at firm’s works, the dispatch instructions will

be issued for the respective store(s) as per requirement of Nigam. Sample(s) will be drawn from the lot(s) received in store(s) and will be subjected to the following test(s):

a) One transformer will be selected out of every lot of 20 Nos. or part thereof for measurement of total Losses at 50% & 100% loading at rated voltage; No Load current (at 100% and 112.5% of rated voltage); Impedance voltage. The testing shall be arranged either at purchaser’s own testing lab and / or at independent test lab. The testing charges for such tests shall be borne by the purchaser. The test results will be applicable to the respective lot of 20 Nos. from which sample was drawn.

b) If dispatch instructions are less than 20 Nos. than one sample shall be selected from each store(s) and the test results so obtained shall be for the quantity consigned/ received by store(s).

The percentage impedance voltage at rated current shall not exceed the permissible limit of 4.5% with plus minus 10% tolerance failing which the sub lot of transformers represented by the sample shall be rejected.

The I.R. values of the sample(s) shall be measured at CTL, Jaipur and it must be more than 50 MEGA-OHM.

One sample out of 100 Nos. transformers or part thereof (the sample whose losses were observed highest in CTL) shall be selected for physical verification/ checking of window height, limb centre and checking of insulation of HV and LV windings at CTL.

NOTE:

If the total losses are found more than 10% of specified losses at 100% loading then apart from rejecting the lot, firm’s balance order would be cancelled and such firms shall not be awarded any order for one year or in next tender of tendered rating to be opened / finalized whichever is later.

645

If the window height and limb centre are found more than 7.5 mm, then apart from rejecting the lot, firm’s balance order would be cancelled and such firms shall not be awarded any order for one year or in next tender of tendered rating to be opened / finalized whichever is later. However, a tolerance of ± 2mm shall be allowed in window height.


33. GUARANTEE PERIOD: Ia) For Out of Rajasthan State Firms

Performance guarantee of the transformer(s) shall be for the period of 60 (sixty) months from the date of dispatch. The date of expiry of guarantee period shall be marked on the rating plate. Transformer(s) failed within such guarantee period shall have to be repaired / rectified free of cost expeditiously.

Firms shall lift G.P. failed Transformers from the stores within 60 days of its intimation positively and deliver the same after repair in next 60 days. In case firm fails to lift G.P. failed Transformer within 60 days, cost of the transformer(s) shall be withheld from its payment bills and in case firm fails to deliver transformer after due repair within 120 days, a penalty at the rate of ½% per week subject to maximum 10%, shall be levied for the late delivery of repaired Transformer(s). Firm shall lift G.P. failed transformers after furnishing safe custody bank guarantee, the slab of safe custody Bank Guarantee as per MM norms.

Ib) For Rajasthan State Firms

Performance guarantee of the transformer(s) shall be for the period of 60 (sixty) months from the date of dispatch. The date of expiry of guarantee period shall be marked on the rating plate. Transformer(s) failed within such guarantee period shall have to be repaired / rectified free of cost expeditiously.

Firms shall lift G.P. failed Transformers from the stores within 60 days of its intimation positively and deliver the same after repair in next 60 days. In case firm fails to lift G.P. failed Transformer within 60 days, cost of the transformer(s) shall be withheld from its payment bills and in case firm fails to deliver transformer after due repair within 120 days, a penalty at the rate of ½% per week subject to maximum 10%, shall be levied for the late

646

delivery of repaired Transformer(s). Firm shall lift G.P. failed transformers after furnishing safe custody bank guarantee, the slab of safe custody Bank Guarantee as per MM norms.





IPDS/TN

KVA

Sr.No.

Date of supply


Date of failure

Date of repair

Guarantee period

extended.

647



iv) All due care should be taken to ensure that the original name plate and identification plate provided should not be removed from the position at which they are fixed originally. In case it is felt that these are loose then it should be repaired suitably by welding or revetting.

v) Test checking of G.P. failed transformers will be allowed to the supplier at Nigam’s store before lifting of G.P. failed distribution transformers to repair at supplier’s works so that minor mistakes like loosing of connections/ replacement of fuse wire/ replacement of MCCB be carried out at Nigam’s stores.

vi) G.P. repaired Distribution transformers may be got tested at CTL as per the sampling plan of new transformer except the physical opening test. The 10% tolerance (as per IS:2026 Part-I/1977) be allowed on total losses at 50% and 100% loading for the transformers failed under guarantee period for testing at firms’ works as well as in CTL testing.

vii) An undertaking shall be furnished by the firms, who will supply the amorphous distribution transformers that in case transformer fails beyond guarantee period, it shall be repaired by them on the rates, terms & conditions of Nigams existing CRC for repair of distribution transformers and in case firm denies to repair the transformers under CRC, such firms shall not be awarded order in subsequent tender.

NOTE:- Firm shall keep the records for at least 8 years of transformers supplied by them

NOTE:- firms should have “BEE” Labeling.

648

ANNEXURE-A


63/100 KVA (AL) WOUND ,11 / 0.433 KV 3-STAR RATING DISTRIBUTION TRANSFORMER

S.

No. P A R T I C U L A R S AS OFFERED

63 KVA 100 KVA






(b) L V


(b) L V

7. Rated Frequency

8. No. of phases


(b) L V



12. Max. temperature rise obtained by the transformer when run at the maximum ambient

649

S. No.

P A R T I C U L A R S AS OFFERED

63 KVA 100 KVA

temp. of 50 ° C



13. Hottest spot temperature, at rated current and voltage, calculated corresponding to the yearlyweighted average ambient temp. of 35 ° C

14. Full Load losses (watts) at75 ° C

15. Total losses (watts) at 75 ° C(a) At 50% loading

(b) At 100% loading

16.


17. Percentage resistance at full load and at 75° C













650

S. No.


63 KVA 100 KVA











HV

LV

26. H V Bushing details:-

(a) Rating of the bushing




(d) IS reference

27. LV Bushing details :-

(a) Rating of the bushing



(c) IS reference

651

S. No.


63 KVA 100 KVA







(g)Current density

(h)Coil I. D

(i)Coil O.D



(m) Weight of covered conductor per transformer

(n) Inter layer insulation (0) No. of vertical spacers per circle (in the annular gap between LV & HV)








652

S. No.


63 KVA 100 KVA

(h)Current density

(i)Coil I. D.

(j) Coil O.D. (k) Coil axial length



(n) Weight of covered conductor per

transformer (o) Inter layer insulation

(p) No. of vertical spacers per circle






(b) )Between HT outside surface & tank inside ( HV & LV bushing side)




(g)Radial clearance between core &


653

S. No.


63 KVA 100 KVA

(h)Phase to phase Clearance between Limbs (HV Conductors), with a minimum of 2 Nos. x 1mm Press board covering the tie rods





(i) Length

(ii) Breadth

(iii) Height


(i) Sides

(ii) op

(iii) Bottom


(i) No. of stiffeners around the tank

(ii) Size



(c) Whether cooling calculations attached?

(d) No. of tubes on each side

35. Size of core frame channels

654

S. No.


63 KVA 100 KVA

36. Core details

(i) Tie rod details

(ii) Size of core frame channels

(iii) Core diameter (mm)

(iv) Core stud details

(v) Core coil assembly base supports ( 2 Nos )

(vi) Window Height (mm)

(vii) Limb Center (mm)




(c) Oil weight





(a) Length

(b) Breadth

(C )Height


(Signature)

Name & Designation with seal of the bidder

655

TECHNICAL SPECIFICATION FOR SUPPLY OF 11/0.433KV, 160 KVA RATING OUTDOOR TYPE (ALUMINIUM WOUND) THREE STAR RATING DISTRIBUTION TRANSFORMERS.

1. SCOPE:

This specification covers the design, engineering, manufacture, assembly, inspection and testing at manufacturer’s works before supply of Oil immersed, Oil Natural Air Natural (ONAN) outdoor type 11KV/433 V, three phase, 50 Hz, double wound core type, outdoor Type, Aluminium Wound Three Star Rating Distribution Transformers of 160 KVA rating, complete with fittings and accessories for use in Distribution System.


1.1.1 It is not the intent to specify herein complete details of design and construction. The equipment offered shall conform to the relevant standards and be of high quality, sturdy, robust and of good design and workmanship complete in all respects and capable to perform continuous and satisfactory operations in the actual service conditions at site and shall have sufficiently long life in service as per statutory requirements. The dimensional drawings attached with this specification and the notes thereto are generally of illustrative nature. In actual practice, not withstanding any anomalies, discrepancies, omissions, incompleteness, etc. in these specifications and attached drawings, the design and constructional aspects, including materials and dimensions, will be subject to good engineering practice in conformity with the required quality of the product, and to such tolerances, allowances and requirements for clearances etc. as are necessary by virtue of various stipulation in that respect in the relevant Indian Standards, IEC standards, I.E. Rules, I.E Act and other statutory provisions.

1.2 The Tendered / supplier shall bind him to abide by these considerations to the entire satisfaction of the Purchaser and will be required to adjust such details at no extra cost to the purchaser over and above the tendered rates and prices.


656



Note: Wherever ISS are mentioned, equivalent or better International standards are also acceptable

IS: 1180 (PART-I)/2014: Specifications for outdoor type oil immersed distribution transformers up to and including 2500 KVA, 33 KV Class.






Transformer bushing (17.5 KV). IS:12444 : Specification for copper wire rod.

IS:7421 : Porcelain Transformer Bushings for low voltage – upto 1 KV.







IS:6162 : (Part II) : Specification for paper covered Aluminium rectangular conductors IS:104 : Ready mixed paint, brushing zinc chromate, painting IS:649 : Testing of steel sheets and strips for magnetic circuits. IS:2362 : Determination of water content in oil for porcelain bushing transformers.

657

IS: 4257: Dimensions for clamping arrangements for bushings. IS:5561: Electrical Power Connector IS:6262: Method of test for power factor and di-electric constant of electrical insulating

liquids. IS:6792: Determination of electrical strength of insulating oil. IS 6160 : Rectangular conductor for electrical machines. IS:10028 : Selection, Installation and maintenance of transformers IS: 3401 : Silicagel IS: 5/1961: Colour for ready mixed paints REC Specification No. 2 REC Specification No. 39/1993 CEA Specification, Chapter 4

Material conforming to other internationally accepted standards, which ensure equal

or higher quality than the standards mentioned above would also be acceptable. In case the Bidders who wish to offer material conforming to the other standards, salient points of difference between the standards adopted and the specific standards shall be clearly brought out in relevant schedule. Four copies of such standards with authentic English Translations shall be furnished along with the offer.




1000 mtrs. The equipment shall be for use in moderately hot and humid tropical climate,



The Transformers shall be suitable for outdoor installation with three phase 50 Hz 11 KV system in which the neutral is effectively earthed and should be suitable for outdoor

658

service as step down transformers under fluctuations in supply voltage upto plus 10% to minus (-) 15% permissible under Indian Electricity Act and rules there under.





iv) Rated LT voltage : 433 V (P-P)/250 V (P-N)

Line current HV : 8.4 A

Line Current LV : 213.33 A

v) Frequency : 50 Hz





x) Percentage impedance at 75°C : 4.5 % / 5.0% respectively






659










i) 35 Deg. C in oil by thermometer. ii) 40 Deg. C in winding by resistance


The transformer shall be capable of giving continuous rated output without exceeding the specified temperature rise. Bids not meeting the above limits of temperature rise will be treated as non responsive.

660

It must be noted carefully that readings for hot resistance after shut down shall be taken separately for HV & LV windings, which means, after completing the readings for one winding (HV or LV), the transformer shall be connected again and rated current passed for another 60 minutes (min.) and shut down taken again to take hot resistance readings for the remaining winding. This is in line with the requirement of CBIP manual, to ensure proper resistance v/s time curves.

Hot Spot temperature not to exceed 98 Deg. C when calculated over an annual weighted average ambient temperature of 35 Deg. C as per IS:2026 (Part-II Clause 4.9.4).

However, the transformer shall be designed for class ‘A’ insulation. 8. UNBALANCE CURRENT:


9. IMPEDANCE:

The percentage impedance at rated current at 75°C shall be 4.5% with (+/-) 10% tolerance.

10. TAPPINGS:

No taps are to be provided in these transformers. 11. FREQUENCY:



661





11000 Volt A I R 255 mm 140 mm




PARTICULARS 160 KVA




d) Between LV windings to core (Bare conductor) 5 mm

e) From top of yoke to inside of top cover of tank (with gasket) 75 mm

f) Between LV/HV winding (Radial bare conductor Clearance) 11 mm



662

13. TEST VOLTAGE:





0.433 KV ---- ---- 3 KV





The header pipe connecting radiator bank to the tank shall be rectangular in shape with

approximate size of 100x20 mm. The placement of top header pipe to the tank body shall be above the top of yoke, to facilitate cooling for hot oil sump over top yoke.

Cooling area of the tank/radiators should be sufficient to dissipate the guaranteed losses

satisfactorily (as per Clause No. 7). Necessary calculations in this regard shall be furnished by the Bidder with their tender. For the purpose of heat dissipation calculations, the following criteria shall be adopted:


663


ii) Elliptical tube of section 57 -- 55 watts/meter length. Note: The provision of radiator is essential in distribution transformers to be supplied against this tender.


i) MATERIALS:

Double paper covered Aluminium Conductors shall be used for 11 KV class transformers of each rating. The covering shall be conformed to applicable ISS.

ii) CONSTRUCTION:




used.

For bottom and top yoke insulation, only PC Board of min. 2 mm thickness will be

664




Min. number of coils on HV side shall be 6 (six) per phase for each rating transformers. Dovetailed shaped radial spacers shall be placed between HV coil sections, suitably – locked with vertical spacers around the circumference of the coils. The number of such spacers shall be minimum 8(eight).

Current Density The current density for HV and LV conductor shall not exceed the value given hereunder:



160 KVA 1.6 1.6




C) HV Winding: The following method shall be adopted for taking out HV connections- a) The coil series connections shall be made by soldering / brazing only, after

completely removing the insulation from the ends.

665

b) Starting and finishing leads of HT coils shall be covered with empire sleeve(s) of proper size. These leads should be clamped with the body of the winding with the help of cotton twine during manufacture of the coils.


d) All the above leads shall then be clamped tightly with cotton twine directly on to the special frame/bracket making “Pie” shape connection. This structure could be made up of Bakelite/ Permalli wood/ laminated PC board flats, having minimum size of 25x6.0 mm. Line leads leading to the HV bushing terminals shall be directly clamped to the horizontal support bar of the “Pie” structure so that any tension which may develop in the HT leads due to jerks or at the time of making the connection , is not passed to the HT coils.


B) LV Winding :

a) The LV connection shall be taken out by cut on the top yoke channel duly reinforced to compensate for the mechanical strength.

b) The layers in LV Coil may be either even or odd in numbers but minimum layers shall be two.

c) LV star point shall be formed of copper flat of sufficient strength. Leads from

winding shall be connected to the flat by brazing.

d) Firm connection of LV winding to bushing shall be made of adequate size of “ L shape flat”. Connection of LV coils to L shape flat shall be by brazing only.



bushing.

666

g ) For Aluminium windings, L&T, ALKAPEE aluminium brazing rods with suitable flux will be used.

16. CORE CONSTRUCTION & CORE COIL ASSEMBLY DETAILS: A. CRGO CORE

(i) The core shall be stack/ wound type of high grade cold rolled grain oriented annealed steel laminations, having low loss and good grain properties, coated with hot oil proof insulation, bolted together to the frames firmly to prevent vibration or noise. All core clamping bolts shall be effectively insulated. The complete design of core must ensure the permanency of the core losses with continuous working of the transformers. The value of the flux density allowed in the designs and grade of laminations used shall be clearly stated in the offer, along with the curves. The transformer core shall be constructed out of the prime class of materials. CRGO Lamination used shall be of prime grade and not second grade steel laminations.

(ii) It will be mandatory for all the transformer manufacturers to use only PRIME grade CRGO Laminations of M-4 grade/ 0.27 mm (with tolerance as per relevant ISS) thickness or better with specific loss of 0.89 watt per kg. at 1.6 Tesla or any other combination of better grades with any thickness subject to maximum specific loss of 0.89 watt per kg. at 1.6 Tesla will also be acceptable. The bidder shall furnish the core loss (watt/Kg.) and power (VA/Kg) curves of the laminations used. The core shall be properly stress relieved by annealing in inert atmosphere. The transformer shall be suitable for over fluxing (due to combined effect of voltage and frequency) upto 12.5% without injurious heating. The operating flux density shall be such that there is a clear safe margin over the fluxing limit of 12.5%.

(iii) Full mitred core construction technique shall be adopted. Top yoke & bottom yoke pieces shall all be in one single piece and no cut pieces shall be acceptable. The cross sectional area of yoke & limb shall be approximately same.


(v) Flux density at rated voltage and frequency of core and yoke shall not be more than 1.6 Tesla. The Over fluxing shall be limited to 12.5% of rated value and flux density at 112.5% of rated voltage does not exceed by 1.9 Tesla.

667

The No Load Current (magnetising current) of each rating of transformers at rated voltage and at 112.5% of rated voltage shall not exceed the values given below:

The tolerance on magnetizing current shall be +30% on declared value of magnetizing current as per IS:2026

(vi) For free circulation of oil axial and radial ducts of the following minimum thickness shall be provided:

between HV n mm

Tolerance of ± 1 mm on above axial ducts width shall be allowed provided that total clearance between HV to LV coil (bare conductor) is maintained as minimum 11 mm.

(B). AMORPHOUS METAL CORE a) The core shall be high quality amorphous ribbons having very low loss formed into wound cores of rectangular shape, bolted together to the frames firmly to prevent vibration or noise. The complete design of core must ensure permanency of the core loss with continuous working of the transformers. The value of the flux density allowed in the design shall be clearly stated in the offer. Curve showing the properties of the metal shall be attached with the offer.


2. MS core clamps shall be painted with varnish or hot oil resistant paint 3. Suitable provision shall be made in the bottom core clamp / bottom plate of the transformer to Arrest movement of the active part.



3% 6%

Width of axial duct in mm in between insulating cylinder Radial duct coils i

and


5 4 8

668


d) Flux density should not be more than 1.6 Tesla for Amorphous core. No load current shall not exceed 3% of full load current and will be measured by energizing the transformer at 433 volts 50 c/s on the secondary. Increase of voltage of 433 volts by 12.5% shall not increase the no load current disproportionately high and shall not exceed i.e., 6%. Test for magnetic balance by connecting the LV phase by phase to rated phase voltage and measurement of an, bn, cn voltage will be carried out.

NOTE: Equal Weightage shall be given to the transformers with Amorphous metal core and CRGO.




On the core-coil assembly, core clamping channels, tie rods, core studs, spacers, assembly base supports, etc. of each rating shall be provided as per details given hereunder:

Sr. No.

Item Particulars




669


2 Nos. MS channels OF 100x50x6t mm. with minimum peripheral coverage of 40%.


4 MS Channels of 100x50x6t mm. size (applicable for CRGO/ Amorphous Transformers)


The assembly fixing boss nut(s) are to be welded,20-30 mm off the centre line (and diagonally) of the tanks, so that assembly shifting during transport etc. is prevented. M S Channel, Tie Rods etc should be painted with hot oil and corrosion resistant paint before use.

All core-coil assembly shall be indelibly marked / punched on core channel / a identity plate welded on core channel with following details:


2. IPDS / TN No:

3. Rating:


In case if above marking is not found on the core assembly of physically opened transformer selected for physical verification during final inspection then no further inspection shall be carried out and re-inspection charges shall be payable by the supplier.

17. TRANSFORMER TANK:

(a) Transformers tank shall be rectangular in shape, robust in construction and with adequate strength to withstand the pressures developed at the time of severe fault conditions. The tank body shall be suitably stiffened to achieve the object. The tank sheet shall be electrically welded both from inside and outside to impart proper mechanical strength and to plug leakage of oil. All joints of tank and fittings shall be oil tight and no bulging shall occur during service. The tank design shall be such that the core and windings can be lifted freely. The tank plates shall be of such strength that the complete transformer when filled with oil may be lifted bodily by means of lifting lugs provided. The stiffeners

670

shall be welded full length. All the welding shall be continuous. The top cover plate shall be sloping down by more than 15 mm, opposite LV bushings side. The top cover shall be extended by 5 mm by all the sides beyond the flange of the top cover. Accordingly length of the lifting hooks shall be extended. The top cover shall have no cut at point of lifting lug. No negative tolerance in the tank dimensions is acceptable in actual supply. The tank shall be fabricated by welding at corners. No horizontal or vertical joints in tank side walls and its bottom and top cover will be allowed.

(b) Minimum size of MS Sections to be used in construction of each rating of transformer tanks shall be as under:

Sr. No.

I T E M S Parameters






6 No. of stiffeners (To be welded on four side of the tank in the angle forms inverted “L”)

2 No.



9 Cover Bolt Size M12x40L/ 4/8 x 1.5”


11 Lifting lugs 2 Nos. 10t mm flat

12 Tank Base Channel (ISMC Type) at a C-C distance of 415 mm) 2 (100x50x6t mm)

* Tank base channels shall be provided parallel to the bushing lines.

671

NOTE: Each cover bolt shall be complete with two flat washers, one nut and one spring washer.

(j) The 12 Nos. nuts & bolts ( 4Nos each on length sides & 2 nos each on widths sides of tank body) to be tag welded on top cover / tank body of the transformer.

(ii) The 04 Nos. Anti Theft Fasteners shall be provided - one each on all four sides in centre of body of transformer. Two holes shall be provided – one on top cover and other on collar of transformer to facilitate providing of 2 Nos. poly-carbonate seals on longitudinal side.

Additional 8 Nos. stainless steel anti theft fasteners (nuts and bolts) used for fixing the base channel on structure shall be provided by the supplier.


MEASUREMENT OF SHEET THICKNESS OF TRANSFORMER TANK:







For transformer tank sheet thickness verification, the average of top and bottom cover be taken collectively and not individually to decide acceptance/ rejection of transformers.


672


··· Sheet thickness of transformer tank for Distribution Transformers as per relevant tender specification are as under for ready reference:

Sr. No.


Bottom Cover (mm)

Side of Tank

(mm)

1 160 KVA Three Phase 5.0 5.0 4.0


For example:




-------------

100

In case any dimension in transformer tank sheet thickness found beyond aforesaid limit of (-) 5% will not be acceptable to the Discom and the relevant sub-lot shall stand rejected and the lot of such transformers will have to be replaced by the firm.



673

(c ) Lifting Lugs: Two Nos. welded heavy duty lifting lugs of MS plate of 10mm thickness, suitably reinforced by vertical supporting flat welded edge wise below the lug on side wall shall be provided, these shall be so extended that cutting of bent plate is not required


i) The gasket provided in between top cover plate and tank shall be of min. 6 mm thick neoprene rubberized oil resistant cork sheets conforming to type B or C as per IS 4253 part II.


iii) Height of the tank shall be such that minimum clear height is to be achieved between top of yoke and under side of the tank cover (with gasket in place) as under:

a) 160 KVA rating - 75 mm

iv) All steel screws, nuts and fasteners exposed to atmosphere shall be either galvanised or cadmium plated or electroplated.


minimum thickness of gaskets shall not be less than 6 mm for tank cover and

4mm for HT/LT gasket washers.

vi) Talbros make neoprene/nitrile based rubberized cork sheet – grade RC-70-C shall only be used as gasket material. Alternatively, other makes of gaskets having type designations as under can also be used, if ‘Talbros’ make gasket is not available:







674



Steel surface shall be prepared by sand / shot blast or chemical cleaning including phospating, as per IS 3618. Heat resistance paint (Hot oil proof) shall be provided inside tank. On external surface, one coat of thermo-setting powder paint or 2 coat of Zinc chromate followed by two coat of synthetic enamel paint of olive green colour, confirming to shade No. 220 of IS: 5-1961, shall be applied in order to distinguish of star level transformers.




Inside

Outside

01 01



c) Hot Oil Paint

Outside

Outside

Inside

02

02

01



675


“The following standard fittings shall be provided on each transformer:

a) Earthing terminals of M12x40L/ 4/8x1.5” with tinned lugs and symbol – (2 Nos.)

b) Lifting lugs – (2 Nos. for main tank).

c) Rating and terminal marking plate (non-detachable), details to be included


clearly marked - (1 No.)

d) Bi-metallic terminal connectors on HV bushings and L-type connectors on LV bushing shall be fitted before dispatch.

e) Oil level gauge of minimum 150 mm length of prismatic glass, indicating three positions of

oil, marked as follows, shall be provided:

1) -5 °C - Min.

2) 30 °C - Nor.

3) 98 °C – Max.

f) Silica Gel Breather shall be aluminium/ metal – (1 No.)

g) Thermometer pocket, 12.5 mm dia with cap. shall be provided –– (1 No.)

h) Oil filling hole (1/¼”dia) with cover and gun metal drain valve of 20 mm size on the oil conservator.

i) a) One filter valve of gun metal of 20 mm size at the top side of the tank.

b) One drain cum sampling cum filter valve of gun metal at the bottom side of the tank but opposite of the top filter valve. The necessary arrangement for locking on this valve by providing MS Sheet box duly welded on tank body shall be made.

c) The valve shall be either of Leder or L&T or AUDCO make and wheel type.

676

j) HV Bushings. These shall be of 17.5 KV/250 A class, porcelain/ polycrate with non adjustable, single gap type arcing horns – (3 Nos.)

k) LV Bushings. 1.1 KV class: (4 Nos.)

a) 630 A (M 20 stem) – for 160 KVA rating.

l) Brass rod 12 mm diameter for HT Terminals of each rating – (3 Nos.)

m) Brass rod for LT Terminals of each rating – (4 Nos.)

a) 20 mm diameter for 160 KVA rating transformer

n) 100 mm dial type thermometer for oil temperature indication.

o) Two pulling eyes one each on opposite side of the tank.

p) Explosion vent (pressure relief valve ) and pipe connected with conservator.

q) Air release device. Note:

1. As mentioned above, suitable bi-metallic connectors on HV bushing and L-type connector shall be provided, having capacity of about 1.5 times the rated current of the transformer.

2. LV/ HV Connector shall not be the integral part of the bushing stems”. 19. CONSERVATOR:


conservator. In addition, the cover of the main tank shall be provided with a self-sealing pressure

release device designed to operate at minimum pressure of 8 PSI (0.564 Kg./cm. Sq.) to enable

release of air trapped within the main tank, unless the conservator is so located as to eliminate the

possibility of air being trapped within the main tank. The conservator shall be of cylindrical shape

677

and it should be provided above the HV bushing with a minimum clearance of 50 mm and suitably

inclined to maintain the clearance.

The total inner volume of conservator shall be minimum of 10% of the volume of oil in each

rating of transformer. The inside diameter of the pipe connecting the conservator to a main tank

shall be min. of 50 mm and it should be projected into conservator in such a way that its end is

approximately 25 mm above the bottom of conservator so as to create a sump for collection of

impurities. The min. oil level (corresponding to – 5 deg. C.) should be above the sump level. The

connecting pipe from conservator tank to main tank shall have a sloping flap so that oil falling from

pipe shall not fall directly on the active job.

The oil filling hole cap of conservator should be welded with tank body with the help of

suitable inverted ‘U’ shape clamp.





The transformer shall be provided with outdoor type 3 Nos. 17.50 KV / 250 A class porcelain bushings, conforming to IS:3347/1972 & IS:2099/1973 from the manufacturer of repute. The HV bushings shall be on top of the tank and shall be fitted on a pocket made on top cover. These pockets shall be such that the HV bushing is tilted more towards the HV side. The bushing of R & B may also be tilted sidewise to maintain the required electrical clearance. The bushings rods and nuts shall be made of brass. The inner porcelain portion of the bushing shall be projected about 50% of the length inside the bushing pocket. HT bushing(s) mounting bolts should be tag welded.

678


The arcing horn(s) shall be single gap and fixed type. HV bushings shall be of reputed make such as BEPCO, JAYSHREE, WSI, SESHASAYEE, JAIPUR GLASS, BPPL Bikaner, Agarwal salt Co. Bikaner, Baid Sanitary Works, Bikaner/ Krishna Ceramics, Nasirabad or any other make - approved by the purchaser. The HV bushings shall generally conform to IS: 3347 and IS: 2099. Embossing showing the manufacturer’s name and month & year of manufacture shall be clearly visible on HV bushings, even after fixing on transformer(s).


“LV Bushing side shall be on side of the tank but opposite to the HV Bushing side. 4 Nos. LV Bushings (1.1 KV/630 A for 160 KVA rating transformers) shall be mounted on the tank wall. Projection of the LV pocket shall be such that inner portion of the LV stem shall not project more than 20 mm inside the tank, to facilitate unhindered lifting of the core coil assembly. Bushing stem of M 20 size shall be of brass. Rest of the components shall conform to the requirement of IS:3347 (Part I/section 2). The LV bushings shall be of reputed make such as JSI, JAIPUR GLASS, BPPL Bikaner, Baid Sanitary Works, Bikaner, Agarwal salt Co. Bikaner, or any other make approved by the purchaser. The LV bushings shall generally conform to IS: 3347 and IS: 7421”.



The make of Transformer Oil shall be either APAR/SAVITA/ RAJ LUBRICANTS/ ANAMIKA/SHARAVATI/ MADRAS PETRO/ RAJ PETROL/ LUBRICHEM, MUMBAI/ OPANAMA PETROCHEM, ANKELSHWAR/ TASHKENT OIL, VADODARA/ COLUMBIA. The transformer oil sample taken from the transformer shall be subject to testing as per provisions ofIS:1866.


679

24. IDENTIFICATION DETAILS: A) Rating & terminal marking plate: Each Transformer shall be provided with non detachable name, rating and terminal marking plate fitted in a visible position. All details shall be given on one plate. Material of the plate shall be stainless steel only. Thickness shall be 0.9 mm (with a tolerance of ±0.1 mm). The plate shall be made absolutely undetectable either through welding or riveting or through any other approved method.



(i) P.O. No. - month & year. (ii) IPDS/TN No. iii) Date of dispatch - month & year

iv) Date of expiry of guarantee period – month & year

iii) Maximum Guaranteed No Load & Load Loss Figures iv) Recommended fuse sizes for HV & LV sides. v) Name & Full address of the manufacturer. vi) Capacity of the transformer. vii) Rating of the transformer.


I) Identity Plate :- A M.S. plate of size 75 x 75 x 2.5 mm shall be continuously welded to the main tank body below the middle HV bushing and in clearly visible position, with following details clearly punched :


……… KVA , S.NO. ……….

680

……….MAKE ……………. II) Identification Mark :- In addition to above, the following identifying details shall be clearly punched on top cover near lifting lug, towards neutral side, with minimum 10 mm x 10 mm size punch letters.

MAKE

Sr. No.

IPDS/TN


Further following details is to be punched on all the four sides of the tank preferably in center. The dimensions of letters should be 10x10 mm. The punching shall be clearly distinct and visible.

a) Make

b) IPDS/TN No. c) Sr.No.

B) To punch the details make, TN No. & Sr.No.of transformer at two places ( i.e. at the top cover

& transformer tank). The punching shall be distinct and visible. C) Technical Plate- In addition to existing provision of identity plate and name plate one plate also

be affixed on the transformer mentioning the following details:-

a) Name of the Firm

b) TN No. c) Make d) Rating e) Core :-

i. Core Dia ii. Core Area

f) LV Coil :- 1. ID/OD Dimensions 2. Conductor Size

g) HV Coil :-

681

a. ID/OD Dimensions b. Conductor Size

h) Limb Centre i) Window Hight


TRANSFORMERS:

Guaranteed Technical particulars of the transformers offered shall be furnished in A-4 size paper in the proforma appended herewith at Annexure-A. Complete details shall be furnished. Tolerances on weight quantity and dimension figures shall be ± 5% at the tender stage, subject to maintaining the minimum electrical clearances as per the specification. However, no negative tolerance shall be allowed on the short circuit type tested design. Electrical performance data shall be subject to tolerances as per ISS, unless otherwise specified in this specification. However, the Total losses at 50% & 100 % loading shall be maximum guaranteed without any positive tolerance.


The bidder shall furnish type test certificates of offered design / similar design (not older than 5 years), wherever available,with the bid


The tenders shall be accompanied with the following drawings / Calculation sheets, as per the offered designs. The drawings shall be only on A-3 (420 x 297 mm) size paper and calculation sheet shall be on A-4 size paper only.

i) Name rating / diagram plate drawing. j) Outline and general arrangement drawing. k) Core-coil assembly drawing. l) Core section (for limb and yoke) along with flux density calculation sheet / drawing. m) Cooling area calculation sheet. n) Thermal Ability short circuit calculation sheet. o) Core loss and magnetization curves of the laminations. p) Heat dissipation calculations (heat dissipation by tank walls excluding top and bottom




682

The tenderer shall furnish the details type tests conducted on the Transformers offered to supply.








manufacturing programme so that arrangements can be made for inspection. The supplier shall give minimum fifteen days advance intimation to enable the purchaser to depute his authorised representative for witnessing of various tests on the equipment/ material as detailed below:

NOTE: Penal provision shall be made for any short technical parameters found / noticed in the transformers at any time even beyond guarantee period.

683

30 ROUTINE/ ACCEPTANCE TESTS:

D) 100% testing of the Distribution Transformers shall be carried out at firm’s works for measurement of total load losses at 50% & 100 % loading. Remaining testing shall also continue to be carried out as per practice.

All the assembled/ finished transformers prior to despatch shall be subjected to routine tests as

per IS:2026. Minimum 25% of the offered lot size samples subject to minimum 5 Nos will be taken for routine and acceptance tests. The supplier shall invariably furnish manufacturer’s routine test certificate along with inspection call of the offered transformers for pre-despatch inspection. The inspection offers without furnishing of routine test certificates as per ISS of all the transformers offered for final inspection shall not be entertained, and any delay on this account shall be to firm’s account.


1. Insulation resistance 2. Separate source voltage withstand test 3. Induced over voltage withstand test 4. Measurement of windings resistance cold (at or near the test bed temperature)



7. Measurement of total losses at rated voltage and normal frequency (at 50% & 100% loading).


9. Checking of rating and terminal marking plate.





684


12. Oil dielectric strength (break down voltage) test shall be carried out on the transformers

opened for physical verification and average value shall be calculated.

13. Checking of manufacturer’s test certificates and invoices for major raw materials shall be done and copies thereof duly signed by firm’s representatives and inspecting officers shall be enclosed with the inspection report.

Invoices of CRGO material shall be provided by the supplier to the inspecting officer at the time of inspection and same shall be verified by the inspecting officer.

Following tests shall also be carried out at manufacturer’s works on one

complete unit of 160 KVA Transformer.

(i) Over Flux Density Test (in the first lot and may be repeated in subsequent lots if desired by purchaser).

(ii) Measurement of unbalance current. (iii) Magnetic Balance Test (See note below) (iv) Oil Leakage Test (See note below)



After successful inspection, the inspecting officer shall seal each and every transformer by sealing the transformer with 2 Nos. poly-carbonate seals on longitudinal side as per the manner mentioned in Clause No. 17 above. Before sealing, the inspecting officer will ensure that all the offered transformers are completed and duly fitted with name, rating and diagram plate, identification plate (on tank body & Top cover) as specified in this specification.

NOTE: Also after inspection/ testing, inspecting officer(s) shall affix Signature Seals also on each Transformer in addition to other seals.

I) INSULATION RESISTANCE MEASUREMENT:

Insulation resistance of selected samples shall be measured with a 2500 V Megger, of

standard make such as M/s AVO, M/s Sakova, M/s Wako, M/s Evershed, Vignole or Metrawatt. The minimum insulation resistance, in Mega Ohms, shall be as indicated in the table below:

20 Deg.C.

30Deg.C.

40Deg.C

50Deg.C.

60 Deg.C.

11000 Volts (HV) 800 400 200 100 50 433 Volts (LV) 400 200 100 50 25

685

ii) MAGNETIC BALANCE TEST:





a) Apply 250 Volts between LV terminals-2u-2n and measure voltages between 2v- 2n & 2w –2n.

b) Apply 250 Volts between 2v-2n and measure voltages between 2u-2n & 2w-2n.

c) Apply 250 Volts between 2w-2n and measure voltages between 2u-2n & 2v-2n.


iii) OIL LEAKAGE TEST:

The oil leakage test shall be conducted on one unit selected from the offered lot of each rating. Transformer complete in all respects shall be subjected to the pressure corresponding to 0.5 Kg / cm² and maintained for three hours. No leakage should occur.

31. TYPE TESTS:

The bidder shall furnish valid type test certificates of same rating of offered item from any CPRI / independent NABL Accredited laboratory/ Govt. approved lab. Such type test certificates should not be older than 5 years as on the date of opening of tender. For this purpose date of conducting type test will be considered. Type test conducted at supplier’s own NABL accredited lab shall not be considered. The following type tests shall be conducted on one unit at NABL/ Govt. approved lab:

a) Lightening Impulse Voltage withstand test at 95 KVp. b) Short Circuit Test.

c) Temperature Rise Test.

d) Air Pressure Test at 80 KPa for 30 minutes and vacuum of 250 mm of mercury for

30 minutes for transformer upto 200 KVA rating and 80 KPa for 30 minutes and vacuum of 500 mm of mercury for 30 minutes for transformer above 200 KVA rating and upto including 2500 KVA rating as per IS:1180 Part-I:2014.

686


Measurement of total losses (at 50% & 100% loading):

(i) After pre-dispatch inspection of material at firm’s works, the dispatch instructions will be issued for the respective store(s) as per requirement of Nigam. Sample(s) will be drawn from the lot(s) received in store(s) and will be subjected to the following test(s):

c) One transformer will be selected out of every lot of 10 Nos. or part thereof for measurement of No load Losses at rated voltage; No Load current (at 100% and 112.5% of rated voltage); Impedance voltage, thickness of tank body sheet and total Losses at 50% and 100% loading at rated current. The testing shall be arranged either at purchaser’s own testing lab and / or at independent test lab. The testing charges for such tests shall be borne by the purchaser. The test results will be applicable to the respective lot of 10 Nos. from which sample was drawn.

d) In case if dispatch instructions are less than 10 Nos. than one sample shall be selected from each store (s) and the test result so obtained shall be for the quantity consigned / received by the store (s).

The percentage impedance voltage at rated current shall not exceed the permissible limit as

specified with allowable tolerance failing which the sub lot of transformers represented by the sample shall be rejected. The transformers selected for total Losses shall also be subjected to magnetizing current and in case found beyond the limit, the lot shall stand rejected.


One sample out of 100 Nos. transformers or part thereof (whose Sr. No. shall be decided by the committee members) shall be selected for physical verification/ checking of window height, limb centre and checking of insulation of HV and LV windings at CTL.

NOTE:


687

The tolerance in window height shall be ±2 mm,If the window height found beyond ±2 mm but up to 7.5 mm then the lot shall be rejected. However if the window height is found more than 7.5 mm, then apart from rejecting the lot, firm’s balance order would be cancelled and such firms shall not be awarded any order for one year or in next tender of tendered rating to be opened / finalized whichever is later.

If the limb centre found more than 7.5 mm, then apart from rejecting the lot, firm’s balance order would be cancelled and such firms shall not be awarded any order for one year or in next tender of tendered rating to be opened / finalized whichever is later..


33 GUARANTEE PERIOD: Ia) For Out of Rajasthan State Firms

Performance guarantee of the transformer(s) with LT protection unit shall be for the period of 60 (sixty) months from the date of despatch. The date of expiry of guarantee period shall be marked on the rating plate. Transformer(s) alongwith LT protection unit failed within such guarantee period shall have to be repaired / rectified free of cost expeditiously.

Firms shall lift G.P. failed Transformers from the stores within 60 days of its intimation positively and deliver the same after repair in next 60 days. In case firm fails to lift G.P. failed Transformer within 60 days, cost of the transformer(s) shall be withheld from its payment bills and in case firm fails to deliver transformer after due repair within 120 days, a penalty at the rate of ½% per week subject to maximum 10%, shall be levied for the late delivery of repaired Transformer(s). Firm shall lift G.P. failed transformers after furnishing safe custody bank guarantee, the slab of safe custody Bank Guarantee shall be as under as per MM norms.



688






IPDS/TN

KVA

Sr.No.

Date of supply

Date of failure

Date of repair

Guarantee period

extended.


689



iv) All due care should be taken to ensure that the original name plate and identification plate provided should not be removed from the position at which they are fixed originally. In case it is felt that these are loose then it should be repaired suitably by welding or riveting.


vi) G.P. repaired Distribution may be got tested at CTL as per the sampling plan of new transformer except the physical opening test. The 10% tolerance (as per IS:2026 part –I/1977) be allowed on total losses at 50% and 100% loading for the transformers failed under guarantee period for testing at firms’ works as well as in CTL testing.


NOTE: Firm shall keep the records for at least 8 years of transformers supplied by them

NOTE: (i) Payments shall be made only after receipt of successful test report from our Central Testing Laboratory (CTL) on the samples selected from the material received at the stores,

690

Annexure‐A



160 KVA (AL) WOUND, 11/0.433 KV 3-STAR RATING DISTRIBUTION TRANSFORMER

S. No. P A R T I C U L A R S AS OFFERED (160 KVA)






(b) L V


(b) L V

7. Rated Frequency

8. No. of phases


(b) L V





691



13. Hottest spot temperature, at ratedcurrent and voltage, calculated corresponding to the yearly weighted average ambient temp. of 35 ° C

14. Total losses At rated current andat 75 ° C

i) At 50% loading ii) At 100% loading

15.

















692










HV

LV





(d) IS reference




(c) IS reference


693







(g)Current density

(h)Coil I. D

(i)Coil O.D












(h)Current density



694


(l) Total no. of turns per phase (m) Resistance per phase at 75 ° C









(b) Between HT outside surface & tank inside ( HV & LV bushing side)




(g) Radial clearance between core &


(h) Phase to phase Clearance between Limbs (HV Conductors), with a minimum of 2 Nos. x 1mm Press board covering the tie rods

(i) Minimum thickness of locking

Spacers between HV coil sections

695


(including 1 mm ring of press board) (j) Maximum clearance of core



(i) Length

(ii) Breadth

(iii) Height


(i) Sides

(ii) op

(iii) Bottom



the tank (ii) Size




attached?


33. Core Details

(i) Size of core frame channels

(ii) Core diameter (mm)

(iii) Core stud details

(iv) Core coil assembly base supports (

696


2 Nos )

(v) Window Height (mm)

(vi) Limb Center (mm)

(vii) Tai Rod Details




(c) Oil weight





(a) Length

(b) Breadth

(C )Height


(Signature)

Name & Designation

with seal of the bidder

697

TECHNICAL SPECIFICATION FOR SUPPLY OF 11/0.433KV, 315 KVA RATING OUTDOOR TYPE (COPPER WOUND) DISTRIBUTION TRANSFORMERS

1. SCOPE:

This specification covers the design, engineering, manufacture, assembly, inspection

and testing at manufacturer’s works before supply of Oil immersed, Oil Natural Air Natural (ONAN) outdoor type 11KV/433 V, three phase, 50 Hz, double wound core type, outdoor Type, Copper Wound Distribution Transformers, complete with fittings and accessories for use in Distribution System.






698


Note: Wherever ISS are mentioned, equivalent or better International standards are also acceptable IS: 1180 Part-1 2014: Specification for outdoor type oil immersed distribution transformers up to and including 2500 KVA,33 KV.
















IS:649 : Testing of steel sheets and strips for magnetic circuits. IS:2362 : Determination of water content in oil for porcelain bushing transformers. IS: 4257: Dimensions for clamping arrangements for bushings. IS:5561: Electrical Power Connector IS:6262: Method of test for power factor and di-electric constant of electrical insulating

liquids.

699

IS:6792: Determination of electrical strength of insulating oil. IS 6160 : Rectangular conductor for electrical machines. IS:10028 : Selection, Installation and maintenance of transformers IS: 3401 : Silicagel IS: 5/1961: Colour for ready mixed paints REC Specification No. 2 REC Specification No. 39/1993 CEA Specification, Chapter 4


3. SERVICE CONDITIONS: The distribution transformers to be supplied against this specification shall be suitable

for satisfactory continuous operation under the following climatic conditions as per IS 2026 (Part- I) latest revision.

i) Peak ambient temperature : 50°C ii) Minimum Ambient Temperature in shade : -5°C iii) Maximum average ambient temp. in a 24 hours period in shade : 45°C iv) Maximum yearly weighted average ambient temperature : 35°C v) Maximum temperature attainable by an object exposed to sun : 60°C

vi) Maximum relative humidity : 100 % vii) Average number of thunder storm days per annum : 40 viii) Average number of rainy days per annum : 120 ix) Average annual rainfall : 15-100 cm x) Number of months of tropical monsoon conditions : 4 Months

xi) Maximum wind pressure : 195 Kg/mt² xii) Altitudes : Not exceeding

1000 mtrs. The equipment shall be for use in moderately hot and humid tropical climate, conducive to

rust and fungus growth.


The Transformers shall be suitable for outdoor installation with three phase 50 Hz 11 KV system in which the neutral is effectively earthed and should be suitable for outdoor service as step down transformers under fluctuations in supply voltage upto plus 10% to minus (-) 15% permissible under Indian Electricity Act and rules there under.


700












x) Percentage impedance at 75°C : 4.5%

xi) Taps (off circuits) : Required As per IS 1180 Part-1/2014.



Primary winding shall be DELTA connected and the secondary winding shall be STAR connected (vector symbol Dyn-11), so as to produce a positive displacement of 30° from the primary to the secondary vectors of the same phase. The neutral of the secondary winding shall be brought out to a separate insulated terminal. The transformers shall be Copper Wound.



The No load voltage ratio(s) shall be 11000/ 433 Volts.

6. THE LOSSES:

701








i) 40 Deg. C in oil by thermometer.

ii) 45 Deg. C in winding by resistance

Temperature rise test shall be conducted on Maximum measured total loss (No load at rated excitation+Load loss at max. current tap at 75 oC) at 100% loading shall be supplied during temperature rise test.



702





9. IMPEDANCE:

The percentage impedance at rated current at 75°C shall be as under:

S. No. RATING percentage impedance at 75°C Tolerance

1 315 KVA 4.5% (+/-) 10%

10. TAPPINGS:

Tappings are Provided as per IS 1180 (Part-1):2014 and its latest amendment.

11. FREQUENCY:







11000 Volt A I R 255 mm 140 mm


703



PARTICULARS 315 KVA





e) From top of yoke to inside of top cover of tank (with gasket)

75 mm




13. TEST VOLTAGE:





0.433 KV ---- ---- 3 KV


704




The header pipe connecting radiator bank to the tank shall be rectangular in shape with approximate size of 100x20 mm. The placement of top header pipe to the tank body shall be above the top of yoke, to facilitate cooling for hot oil sump over top yoke.

Cooling area of the tank should be sufficient to dissipate the guaranteed losses satisfactorily . Necessary calculations in this regard shall be furnished by the Bidder with their tender. For the purpose of heat dissipation calculations, the following criteria shall be adopted:



ii) Elliptical tube of section 57 -- 55 watts/meter length. Note:- The provision of radiator is essential in distribution transformers to be supplied


i) MATERIALS:

Double paper covered copper conductors shall be used for 11 KV class transformers of each rating. The covering shall be conformed to applicable ISS.

705

ii) CONSTRUCTION:




used.






Current Density

706




315 KVA 2.8 2.8



iv) CONNECTIONS AND TERMINATIONS: A) HV Winding: The following method shall be adopted for taking out HV connections-

a) The coil series connections shall be made by soldering / brazing only, after



c) All delta leads from the HT coils as well as HT line leads shall be taken out through

multiple paper covered (MPC) copper wires of sufficient cross section area to impart the desired mechanical strength. The current density in HV lead wire shall not

707

exceed 0.8 A/mm². These lead wires shall be provided with multi layer paper insulation of minimum 1.0 mm thickness i.e. minimum increase in diameter due to paper insulation shall not be less than 2 mm. The layer of glass sleeves/ glass tape shall also be provided on the delta MPC wire and it should be further covered with minimum 12 mm dia SRBP tube. The MPC should also be varnish dipped. The SRBP tube shall be extended in such a way that it is entered upto 50% of bushing height.

e) All the above leads shall then be clamped tightly with cotton twine directly on to the special frame/bracket making “Pie” shape connection. This structure could be made up of Bakelite/ Permalli wood/ laminated PC board flats, having minimum size of 25x6.0 mm. Line leads leading to the HV bushing terminals shall be directly clamped to the horizontal support bar of the “Pie” structure so that any tension which may develop in the HT leads due to jerks or at the time of making the connection , is not passed to the HT coils.


B) LV Winding :

a) The LV connection shall be taken out by cut on the top yoke channel duly to compensate for the mechanical strength.


c) LV star point shall be formed of copper flat of sufficient strength. Leads from winding shall be connected to the flat by brazing.

d) Firm connection of LV winding to bushing shall be made of adequate size of “ L

shape flat”. Connection of LV coils to L shape flat shall be by brazing only.

e) “L” shape Flat shall be clamped to LV Bushing metal part(s) by using nut, lock nut

and washer.


bushing .

g ) For Copper windings, silver brazing rods with suitable flux will be used. 16. CORE CONSTRUCTION & CORE COIL ASSEMBLY DETAILS:

A . CRGO CORE

708





(v) Flux density at rated voltage and frequency of core and yoke shall not be more than 1.6 Tesla. The Over fluxing shall be limited to 12.5% of rated value and flux density at 112.5% of rated voltage does not exceed by 1.9 Tesla.




2% 5%

709



between HV n mm


(B). AMORPHOUS METAL CORE

a) The core shall be high quality amorphous ribbons having very low loss formed into wound cores of rectangular shape, bolted together to the frames firmly to prevent vibration or noise. The complete design of core must ensure permanency of the core loss with continuous working of the transformers. The value of the flux density allowed in the design shall be clearly stated in the offer. Curve showing the properties of the metal shall be attached with the offer.


2. MS core clamps shall be painted with varnish or hot oil resistant paint 3. Suitable provision shall be made in the bottom core clamp / bottom plate of the transformer to Arrest movement of the active part.


d) Flux density should not be more than 1.6 Tesla for Amorphous core. No load current shall not exceed 2% of full load current and will be measured by energizing the transformer at 433 volts 50 c/s on the secondary. Increase of voltage of 433 volts by 12.5% shall not increase the no load current disproportionately high and shall not exceed

Width of axial duct in mm in between insulating cylinder and Radial duct coils i


5 4 8

710

i.e., 5%. Test for magnetic balance by connecting the LV phase by phase to rated phase voltage and measurement of an, bn, cn voltage will be carried out.






Sr.

No.

Item Particulars







4 MS Channels of 100x50x6t mm. size (applicable for CRGO transformers)


711



1. Name of Supplier: 2. IPDS/ TN No:

3. Rating:


In case if above marking is not found on the core assembly of physically

opened transformer selected for physical verification during final inspection then no further inspection shall be carried out and re-inspection charges shall be payable by the supplier.


(a) Transformers tank shall be rectangular in shape, robust in construction and with adequate strength to withstand the pressures developed at the time of severe fault conditions. The tank body shall be suitably stiffened to achieve the object. The tank sheet shall be electrically welded both from inside and outside to impart proper mechanical strength and to plug leakage of oil. All joints of tank and fittings shall be oil tight and no bulging shall occur during service. The tank design shall be such that the core and windings can be lifted freely. The tank plates shall be of such strength that the complete transformer when filled with oil may be lifted bodily by means of lifting lugs provided. The stiffeners shall be welded full length. All the welding shall be continuous. The top cover plate shall be sloping down by more than 15 mm, opposite LV bushings side. The top cover shall be extended by 5 mm by all the sides beyond the flange of the top cover. Accordingly length of the lifting hooks shall be extended. The top cover shall have no cut at point of lifting lug. No negative tolerance in the tank dimensions is acceptable in actual supply. The tank shall be fabricated by welding at corners. No horizontal or vertical joints in tank side walls and its bottom and top cover will be allowed.


Sr. I T E M S Parameters

712

No.







315 KVA rating 2 Nos.

7 Size of M. S. stiffener (mm)

315 KVA rating 40x40x 6 angle





10t mm flat

12 Tank Base Channel (ISMC Type) at a C-C distance of 415 mm)

315 KVA rating 2 (100x50x6t mm)

* Tank base channels shall be provided parallel to the bushing lines. NOTE: Each cover bolt shall be complete with two flat washers, one nut and one spring washer.

(i) The 12 Nos. nuts & bolts ( 4Nos each on length sides & 2 nos each on widths sides of tank body) to be tag welded on top cover / tank body of the transformer.

(ii) The 04 Nos. Anti Theft Fasteners shall be provided - one each on all four sides in centre of body of transformer. Two holes shall be provided – one on top cover

713

and other on collar of transformer to facilitate providing of 2 Nos. polycarbonate seals on longitudinal side.




The following measurements shall be carried out at respective Central Testing Lab (CTL) of the Discom on the supplies of distribution transformers:










714

Sr. No.


Bottom Cover (mm)

Side of Tank

(mm)

1 315 KVA Three Phase 5.0 5.0 4.0


For example:




-------------

100




715

(c ) Lifting Lugs: Four Nos. welded heavy duty lifting lugs of MS plate of 10mm thickness, suitably reinforced by vertical supporting flat welded edge wise below the lug on side wall shall be provided, these shall be so extended that cutting of bent plate is not required


(i) The gasket provided in between top cover plate and tank shall be of min. 6 mm thick neoprene rubberized oil resistant cork sheets conforming to type B or C as per IS 4253 part II

(ii) Nut bolts shall be of size M 12 x 40 mm / 4/8x1.5” long with two flat washers, suitably spaced (as specified) to press the cover.

(iii) Height of the tank shall be such that minimum clear height is to be achieved between top of yoke and under side of the tank cover (with gasket in place) as under:

a) 315 KVA rating - 75 mm

(iv) All screws, nuts, bolts and fasteners exposed to atmosphere are as per IS 1180 Part-1/2014 as follows :- a) Size 12 mm and below:- stainless steel b) Above 12 mm:- Steel with suitable finish like electrogalvanized with passivation

or hot dip galvanized. (v) All sealing washers / gaskets shall be made of oil and heat resistant neoprene or

nitrile rubber. Gaskets made of natural rubber sheet are not permissible. The


(vi) Talbros make neoprene/nitrile based rubberized cork sheet – grade RC-70-C shall only be used as gasket material. Alternatively, other makes of gaskets having type designations as under can also be used, if ‘Talbros’ make gasket is not available:







716



Steel surface shall be prepared by sand / shot blast or chemical cleaning including phospating, as per IS 3618. Inside of tank Oil shall be painted with varnish or oil resistance paint. For external surface, one coat of thermo-setting powder paint or one coat of epoxy primer followed by 2 coat of polyurethane base paint of olive green colour confirming to shade No. 220 of IS: 5-1961 to be applied in order to distinguish of star level transformers. Total Dry film thickness as per IS 1180 Part-1 2014




Inside

Outside

01 01



c) Hot Oil Paint

Outside

Outside

Inside

01

02

01

All steel screws, nuts, bolts and fasteners exposed to atmosphere as per IS 1180 Part-1/2014.

717




a) Earthing terminals of M12x40L/ 4/8x1.5” with tinned lugs and symbol – (2 Nos.)

b) Lifting lugs – (4 Nos. for main tank).

c) Rating and terminal marking plate (non-detachable), details to be included


clearly marked - (1 No.)

d) Bi-metallic terminal connectors on HV bushings and L-type connectors on LV bushing shall be fitted before dispatch.

f) Oil level gauge of minimum 150 mm length of prismatic glass, indicating three positions of oil, marked as follows, shall be provided:

1) -5 °C - Min.

2) 30 °C - Nor.

3) 90 °C – Max.

g) Silica Gel Breather shall be aluminium/ metal – (1 No.)

h) Thermometer pocket, 12.5 mm dia with cap. shall be provided –– (1 No.)

i) Oil filling hole (1/¼”dia) with cover and gun metal drain valve of 20 mm size on the oil conservator.

j) A) One filter valve of gun metal of 20 mm size at the top side of the tank.

718

B) One drain cum sampling cum filter valve of Steel at the bottom side of the tank but opposite of the top filter valve. The necessary arrangement for locking on this valve by providing MS Sheet box duly welded on tank body shall be made.

C) The valve shall be either of Leder or L&T or AUDCO make and wheel type.

k) HV Bushings. These shall be of 17.5 KV/250 A class, porcelain/ polycrate with non adjustable, single gap type arcing horns – (3 Nos.)

l) LV Bushings. 1.1 KV class: (4 Nos.)

a) 630 A (M 20 stem) – for 315 KVA rating.

m) Brass rod 12 mm diameter for HT Terminals of each rating – (3 Nos.)

n) Brass rod for LT Terminals of each rating – (4 Nos.)

a) 20 mm diameter for 315 KVA rating transformer

o) 100 mm dial type thermometer for oil temperature indication.

p) Two pulling eyes one each on opposite side of the tank.

q) Explosion vent (pressure relief valve ) and pipe connected with conservator.

r) Air release device. Note:

1. As mentioned above, suitable bi-metallic connectors on HV bushing and L-type connector

shall be provided, having capacity of about 1.5 times the rated current of the transformer 2. LV/ HV Connector shall not be the integral part of the bushing stems”.

19. CONSERVATOR:

719

When a conservator is fitted, the oil gauge and the breathing device shall be fixed to the conservator. In addition, the cover of the main tank shall be provided with a self-sealing pressure release device designed to operate at minimum pressure of 8 PSI (0.564 Kg./cm. Sq.) to enable release of air trapped within the main tank, unless the conservator is so located as to eliminate the possibility of air being trapped within the main tank. The conservator shall be of cylindrical shape and it should be provided above the HV bushing with a minimum clearance of 50 mm and suitably inclined to maintain the clearance.

The total inner volume of conservator shall be minimum of 10% of the volume of oil in each rating of transformer. The inside diameter of the pipe connecting the conservator to a main tank shall be min. of 50 mm and it should be projected into conservator in such a way that its end is approximately 25 mm above the bottom of conservator so as to create a sump for collection of impurities. The min. oil level (corresponding to – 5 deg. C.) should be above the sump level. The connecting pipe from conservator tank to main tank shall have a sloping flap so that oil falling from pipe shall not fall directly on the active job.

The oil filling hole cap of conservator should be welded with tank body with the help of suitable inverted ‘U’ shape clamp.





The transformer shall be provided with outdoor type 3 Nos. 17.50 KV / 250 A class porcelain bushings, conforming to IS:3347/1972 & IS:2099/1973 from the manufacturer of repute. The HV bushings shall be on top of the tank and shall be fitted on a pocket made on top cover. These pockets shall be such that the HV bushing is tilted more

720

towards the HV side. The bushing of R & B may also be tilted sidewise to maintain the required electrical clearance. The bushings rods and nuts shall be made of brass. The inner porcelain portion of the bushing shall be projected about 50% of the length inside the bushing pocket. HT bushing(s) mounting bolts should be tag welded.




“LV Bushing side shall be on side of the tank but opposite to the HV Bushing side. 4 Nos. LV Bushings (1.1 KV/630 A for 315 KVA rating transformers) shall be mounted on the tank wall. Projection of the LV pocket shall be such that inner portion of the LV stem shall not project more than 20 mm inside the tank, to facilitate unhindered lifting of the core coil assembly. Bushing stem of M 20 & M 30 size shall be of brass respectively. Rest of the components shall conform to the requirement of IS:3347 (Part I/section 2). The LV bushings shall be of reputed make such as JSI, JAIPUR GLASS, BPPL Bikaner, Baid Sanitary Works, Bikaner, Agarwal salt Co. Bikaner, or any other make approved by the purchaser. The LV bushings shall generally conform to IS: 3347 and IS: 7421”.






721

A) Rating & terminal marking plate: Each Transformer shall be provided with non detachable name, rating and terminal marking plate fitted in a visible position. All details shall be given on one plate. Material of the plate shall be stainless steel only. Thickness shall be 0.9 mm (with a tolerance of ±0.1 mm). The plate shall be made absolutely undetectable either through welding or riveting or through any other approved method.



I. P.O. No. - month & year. II. IPDS/TN No.

III. Sr. No. of transformer. IV. Date of despatch - month & year V. Date of expiry of guarantee period – month & year

VI. Maximum Guaranteed Loss Figures at 50% and 100% loading VII. Recommended fuse sizes for HV & LV sides.

VIII. Name & Full address of the manufacturer. IX. Capacity of the transformer. X. Rating of the transformer.

XI. Energy Efficient level-1 and Standard IS1180 Part-1


I) Identity Plate :- A M.S. plate of size 75 x 75 x 2.5 mm shall be continuously welded to the main tank body below the middle HV bushing and in clearly visible position, with following details clearly punched :


……… KVA , S.NO. ……….

……….MAKE …………….

722

II) Identification Mark :- In addition to above, the following identifying details shall be clearly punched on top cover near lifting lug, towards neutral side, with minimum 10 mm x 10 mm size punch letters.

MAKE

Sr. No.

IPDS/TN



a) Make b) IPDS/TN No. c) Sr.No.

B) To punch the details make, IPDS/TN No. & Sr.No.of transformer at two places ( i.e. at the

top cover & transformer tank). The punching shall be distinct and visible.

C) Technical Plate- In addition to existing provision of identity plate and name plate one plate also be affixed on the transformer mentioning the following details:-

A. Name of the Firm B. IPDS/TN No. C. Make D. Rating E. Core :-


F. LV Coil :- 1. ID/OD Dimensions 2. Conductor Size

G. HV Coil :- a. ID/OD Dimensions b. Conductor Size

H. Limb Centre I. Window Hight


723

TRANSFORMERS:

Guaranteed Technical particulars of the transformers offered shall be furnished in A-4 size paper by the Tenderer in the proforma appended herewith at Schedule-A.Complete details shall be furnished. Tolerances on weight quantity and dimension figures shall be ± 5% at the tender stage, subject to maintaining the minimum electrical clearances as per the specification. However, no negative tolerance shall be allowed on the short circuit type tested design. Electrical performance data shall be subject to tolerances as per ISS, unless otherwise specified in this specification. However, the Total losses at 50% & 100 % loading shall be maximum guaranteed without any positive tolerance.


The bidder shall furnish type test certificates of offered design / similar design, (Not older than 5 Years) wherever available, with the bid.



q) Name rating / diagram plate drawing. r) Outline and general arrangement drawing. s) Core-coil assembly drawing. t) Core section (for limb and yoke) along with flux density calculation sheet / drawing. u) Cooling area calculation sheet. v) Thermal Ability short circuit calculation sheet. w) Core loss and magnetization curves of the laminations. x) Heat dissipation calculations (heat dissipation by tank walls excluding top and bottom




The tenderer shall furnish the of type tests conducted on the Transformers offered to supply.

724

The tenderer should possess adequate facilities for inspection and testing of the Transformers, as per requirement of the relevant ISS and this specification. In case any supplier is found not having all the instruments/equipment required for testing, the offer shall be ignored. No borrowing of instruments / equipment shall be allowed. Testing of the Transformers shall also not be allowed at the works of any other manufacturer. However, testing may be allowed at any Government Testing Laboratory. 29. INSPECTION AND TESTING:









A) 100% testing of the Distribution Transformers shall be carried out at firm’s works for

measurement of total load losses at 50% & 100 % loading. Remaining testing shall also continue to be carried out as per practice.

725

All the assembled/ finished transformers prior to dispatch shall be subjected to routine tests as per IS:2026. Minimum 25% of the offered lot size samples subject to minimum 5 Nos will be taken for routine and acceptance tests. The supplier shall invariably furnish manufacturer’s routine test certificate along with inspection call of the offered transformers for pre-despatch inspection. The inspection offers without furnishing of routine test certificates as per ISS of all the transformers offered for final inspection shall not be entertained, and any delay on this account shall be to firm’s account.








7. Measurement of total losses at rated voltage and normal frequency (at 50% & 100% loading).


9. Checking of rating and terminal marking plate. 10. Pressure Test (As per IS 1180 Part-1:2014)

11. Checking of weights , dimensions, fittings and accessories, tank sheet thickness, oil

quantity , material, finish , paint thickness and workmanship as per purchase order and contract drawings.

12. Physical verification of core – coil dimension, internal clearances, provisions of required oil ducts in the HV and LV winding, conductor sizes, individual weights of HV and LV winding core laminations etc., with reference to contract drawings and type test report(s) by dismantling selected unit(s). The physical verification shall be conducted on units equivalent to one unit per 50 Nos or part thereof of offered quantity randomly selected from the offered lot. The dismantled unit(s) after re- assembly shall be accepted by the purchaser after routine testing in presence of his representative.

726






unit of 315 KVA Transformers unit

I. Over Flux Density Test (in the first lot and may be repeated in subsequent lots if desired by purchaser).

II. Measurement of unbalance current. (See note below) III. Magnetic Balance Test (See note below) IV. Oil Leakage Test (See note below)



After successful inspection, the inspecting officer shall seal each and every transformer by sealing the transformer with 2 Nos. poly-carbonate seals on longitudinal side as per the manner mentioned in Clause No. 17 above. Before sealing, the inspecting officer will ensure that all the offered transformers are completed and duly fitted with name, rating and diagram plate, identification plate (on tank body & Top cover) as specified in this specification.


i) RESISTANCE MEASUREMENT:


20

Deg.C. 30Deg.C.

40Deg.C

50Deg.C.

60 Deg.C.

11000 Volts (HV)

800 400 200 100 50

433 Volts (LV)

400 200 100 50 25

727

ii) MAGNETIC BALANCE TEST: This test shall be conducted as an additional test on one sample transformer from

each lot offered for inspection.

The application of low voltage to the middle limb will induce approximately equal voltages on the two end limbs. The application of voltage to the end limbs will induce greater voltage in the middle limb and less voltage in the other end limb. Uniformity of induced voltages shall confirm the healthiness of the transformer windings.


a. Apply 250 Volts between LV terminals-2u-2n and measure voltages between

2v-2n & 2w –2n. b. Apply 250 Volts between 2v-2n and measure voltages between 2u-2n & 2w-

2n.

c. Apply 250 Volts between 2w-2n and measure voltages between 2u-2n & 2v- 2n.


iii) OIL LEAKAGE TEST ( As per IS 1180 Part-1/2014):

The oil leakage test shall be conducted on one unit selected from the offered lot .The assembled transformer for non-sealed and sealed Type with all fittings including bushing in position shall be tested at a pressure equivalent to twice the normal head measured at the base of tank for 8 hrs. There should be no leakage at any point.

31. TYPE TESTS: The bidder shall furnish valid type test certificates of same rating of offered item from a

Govt. approved / Govt. recognized / NABL Accredited laboratory / ILAC i.e. International Laboratory Accredited Laboratory (in case of foreign laboratory). Such type test certificates should not be older than 5 years as on the date of opening of tender. For this purpose date of conducting type test will be considered. Type test conducted at supplier’s own NABL accredited lab shall not be considered. The following Type Test shall be conducted on one unit at NABL/Govt. Approved Lab(Details of Test given in the specification )


728

32. RANDOM SELECTION AND TESTING (RST): After pre-dispatch inspection of material at firm’s works, the dispatch instructions will be issued for the respective store(s) as per requirement of Nigam. Sample(s) will be drawn from the lot(s) received in store(s) and will be subjected to the following test(s):

a) One transformer will be selected out of every lot of 10 Nos. or part thereof for measurement of No load Losses at rated voltage; No Load current (at 100% and 112.5% of rated voltage); Impedance voltage, thickness of tank body sheet and total Losses at 50% and 100% loading at rated current. The testing shall be arranged either at purchaser’s own testing lab and / or at independent test lab. The testing charges for such tests shall be borne by the purchaser. The test results will be applicable to the respective lot of 10 Nos. from which sample was drawn.

b) In case if dispatch instructions are less than 10 Nos. than one sample shall be selected from each store (s) and the test result so obtained shall be for the quantity consigned / received by the store (s).

The percentage impedance voltage at rated current shall not exceed the permissible limit as specified with allowable tolerance failing which the sub lot of transformers represented by the sample shall be rejected. The transformers selected for total Losses shall also be subjected to magnetizing current and in case found beyond the limit, the lot shall stand rejected.

The I.R. values of the sample(s) shall be measured at CTL, Jaipur and it must be more than

50 MEGA-OHM.

One sample out of 100 Nos. transformers or part thereof shall be selected for physical verification/ checking of window height, limb centre and checking of insulation of HV and LV windings at CTL.

NOTE:


If the window height and limb centre are found more than 7.5 mm, then apart from rejecting the lot, firm’s balance order would be cancelled and such firms shall not be awarded any order for one year or in next tender of tendered rating to be opened / finalized whichever is later. However, a tolerance of ± 2mm shall be allowed in window height and limb centre.

729


33 GUARANTEE PERIOD:

Ia) For Out of Rajasthan State Firms Performance guarantee of the transformer(s) with LT protection unit shall be for the period of 60 (sixty) months from the date of despatch. The date of expiry of guarantee period shall be marked on the rating plate. Transformer(s) alongwith LT protection unit failed within such guarantee period shall have to be repaired / rectified free of cost expeditiously.

Firms shall lift G.P. failed Transformers from the stores within 60 days of its intimation positively and deliver the same after repair in next 60 days. In case firm fails to lift G.P. failed Transformer within 60 days, cost of the transformer(s) shall be withheld from its payment bills and in case firm fails to deliver transformer after due repair within 120 days, a penalty at the rate of ½% per week subject to maximum 10%, shall be levied for the late delivery of repaired Transformer(s). Firm shall lift G.P. failed transformers after furnishing safe custody bank guarantee, the slab of safe custody Bank Guarantee as per MM specification.

Ib) For Rajasthan State Firms Performance guarantee of the transformer(s) with LT protection unit shall be for the period of 60 (sixty) months from the date of dispatch. The date of expiry of guarantee period shall be marked on the rating plate. Transformer(s) alongwith LT protection unit failed within such guarantee period shall have to be repaired / rectified free of cost expeditiously.

Firms shall lift G.P. failed Transformers from the stores within 60 days of its intimation positively and deliver the same after repair in next 60 days. In case firm fails to lift G.P. failed Transformer within 60 days, cost of the transformer(s) shall be withheld from its payment bills and in case firm fails to deliver transformer after due repair within 120 days, a penalty at the rate of ½% per week subject to maximum 10%, shall be levied for the late delivery of repaired Transformer(s). Firm shall lift G.P. failed transformers after furnishing safe custody bank guarantee, the slab of safe custody Bank Guarantee as per MM specification.

730





IPDS/TN

KVA

Sr.No.

Date of supply

Date of failure

Date of repair

Guarantee period

extended.




i) All due care should be taken to ensure that the original name plate and identification

plate provided should not be removed from the position at which they are fixed

731

originally. In case it is felt that these are loose then it should be repaired suitably by welding or riveting.

ii) Test checking of G.P. failed transformers will be allowed to the supplier at Nigam’s store before lifting of G.P. failed distribution transformers to repair at supplier’s works so that minor mistakes like loosing of connections/ replacement of fuse wire/ replacement of MCCB be carried out at Nigam’s stores.

iii) G.P. repaired Distribution may be got tested at CTL as per the sampling plan of new transformer except the physical opening test. The 10% tolerance (as per IS:2026 part –I/1977) be allowed on total losses at 50% and 100% loading for the transformers failed under guarantee period for testing at firms’ works as well as in CTL testing.

iv) An undertaking shall be furnished by the firms, who will supply the amorphous distribution transformers that in case transformer fails beyond guarantee period, it shall be repaired by them on the rates, terms & conditions of Nigams existing CRC for repair of distribution transformers and in case firm denies to repair the transformers under CRC, such firms shall not be awarded order in subsequent tender.

NOTE:- Firm shall keep the records for at least 8 years of transformers supplied by them &Payments shall be made only after receipt of successful test report from our Central Testing Laboratory (CTL) on the samples selected from the material received at the stores.

Schedule – A


315 KVA (Cu) WOUND ,11 / 0.433 KV DISTRIBUTION TRANSFORMER

S. No.


315 KVA1. Manufacturer’s Name and Address





(b) L V

732

S. No.


315 KVA6. Rated current

(a) H V

(b) L V

7. Rated Frequency

8. No. of phases


(b) L V







14. Total losses at rated current and at 75 ° C


15.




733

S. No.


315 KVA18. Efficiency at 75 ° C :-



ii) At 100% of full load

iii) At 75% of full load


















734

S. No.


315 KVA HV

LV





(d) IS reference




(c) IS reference







(g)Current density

(h)Coil I. D

(i)Coil O.D



(m) Weight of covered conductor per

735

S. No.


315 KVA transformer









(h)Current density












736

S. No.


315 KVA30. Minimum internal clearances (in oil)

(a) Between HT outside surface and tank inside (non bushing side)







(h)Phase to phase Clearance

between Limbs (HV Conductors), with a minimum of 2 Nos. x 1mm Press board covering the tie rods





(i) Length

(ii) Breadth

(iii) Height


737

S. No.


315 KVA (i) Sides

(ii) op

(iii) Bottom



the tank (ii) Size




attached?


33. Core Details

(i) Size of core frame channels



(iv) Core coil assembly base supports ( 2 Nos )




738

S. No.


315 KVA34. Transformer weight details:



(c) Oil weight





(a) Length

(b) Breadth

(C )Height


(Signature)

Name & Designation


739

TECHNICAL SPECIFICATION FOR SUPPLY OF 11/0.433KV, 500 KVA RATING OUTDOOR TYPE (COPPER WOUND) DISTRIBUTION TRANSFORMERS

1. SCOPE:

This specification covers the design, engineering, manufacture, assembly, inspection and testing at manufacturer’s works before supply of Oil immersed, Oil Natural Air Natural (ONAN) outdoor type 11KV/433 V, three phase, 50 Hz, double wound core type, outdoor Type, Copper Wound Distribution Transformers, complete with fittings and accessories for use in Distribution System.






Unless otherwise modified in the specifications, the Distribution Transformers,

including various accessories, shall generally comply with the following Indian Standards / REC Specifications. The standard(s) shall be with latest amendment, if any, from time to time.

740

Note: Wherever ISS are mentioned, equivalent or better International standards are also acceptable IS: 1180 Part-1 2014: Specification for outdoor type oil immersed distribution transformers up to and including 2500 KVA,33 KV.
















IS:649 : Testing of steel sheets and strips for magnetic circuits. IS:2362 : Determination of water content in oil for porcelain bushing transformers. IS: 4257: Dimensions for clamping arrangements for bushings. IS:5561: Electrical Power Connector IS:6262: Method of test for power factor and di-electric constant of electrical insulating

liquids. IS:6792: Determination of electrical strength of insulating oil. IS 6160 : Rectangular conductor for electrical machines. IS:10028 : Selection, Installation and maintenance of transformers

741

IS: 3401 : Silicagel IS: 5/1961: Colour for ready mixed paints REC Specification No. 2 REC Specification No. 39/1993 CEA Specification, Chapter 4


3. SERVICE CONDITIONS: The distribution transformers to be supplied against this specification shall be suitable

for satisfactory continuous operation under the following climatic conditions as per IS 2026 (Part- I) latest revision.


1000 mtrs.

The equipment shall be for use in moderately hot and humid tropical climate, conducive to rust and fungus growth.


The Transformers shall be suitable for outdoor installation with three phase 50 Hz 11 KV system in which the neutral is effectively earthed and should be suitable for outdoor service as step down transformers under fluctuations in supply voltage upto plus 10% to minus (-) 15% permissible under Indian Electricity Act and rules there under.



742











x) Percentage impedance at 75°C : 5.0%




Primary winding shall be DELTA connected and the secondary winding shall be STAR connected (vector symbol Dyn-11), so as to produce a positive displacement of 30° from the primary to the secondary vectors of the same phase. The neutral of the secondary winding shall be brought out to a separate insulated terminal. The transformers shall be Copper Wound.



The No load voltage ratio(s) shall be 11000/ 433 Volts.

6. THE LOSSES:

743



6.2 The above losses are maximum allowable and there would not be any positive tolerance. Bids with higher losses than the above specified values would be treated as non-responsive.




I. 40 Deg. C in oil by thermometer. II. 45 Deg. C in winding by resistance

Temperature rise test shall be conducted on Maximum measured total loss (No load at rated excitation+Load loss at max. current tap at 75 oC) at 100% loading shall be supplied during temperature rise test at a Govt. approved/ a Govt. recognized/ NABL accredited laboratory/ILAC i.e. International Laboratory Accredited Laboratory/ ILAC i.e. International Laboratory Accreditation Cooperation (in case of foreign laboratory).



744





9. IMPEDANCE:

The percentage impedance at rated current at 75°C shall be as under:

S. No. RATING percentage impedance at 75°C Tolerance

1 500 KVA 4.5% (+/-) 10%

10. TAPPINGS:

No taps are to be provided in these transformers.

11. FREQUENCY:







11000 Volt A I R 255 mm 140 mm


745



PARTICULARS 500 KVA





e) From top of yoke to inside of top cover of tank (with gasket)

100 mm




13. TEST VOLTAGE:





0.433 KV ---- ---- 3 KV

746





The header pipe connecting radiator bank to the tank shall be rectangular in shape with approximate size of 100x20 mm. The placement of top header pipe to the tank body shall be above the top of yoke, to facilitate cooling for hot oil sump over top yoke.

Cooling area of the tank should be sufficient to dissipate the guaranteed losses satisfactorily . Necessary calculations in this regard shall be furnished by the Bidder with their tender. For the purpose of heat dissipation calculations, the following criteria shall be adopted:



ii) Elliptical tube of section 57 -- 55 watts/meter length. Note:- The provision of radiator is essential in distribution transformers to be supplied.


i) MATERIALS:

747

Double paper covered copper conductors shall be used for 11 KV class transformers of each rating. The covering shall be conformed to applicable ISS.

ii) CONSTRUCTION:




used.




A tolerance of upto plus minus 1% shall be permissible on ID and OD and axial length of HV and LV coils. However, the above tolerances are subject to maintaining the min. required clearances. The material and thickness of various insulation provided for

748

phase barrier, foot plate insulation, yoke insulation and core clamp insulation shall be clearly indicated in the drawing and in any case shall not be inferior to those used in type tested transformers.


Current Density The current density for HV and LV conductor shall not exceed the value given hereunder:



500 KVA 2.8 2.8



iv) CONNECTIONS AND TERMINATIONS: A)HV Winding: The following method shall be adopted for taking out HV connections-

a) The coil series connections shall be made by soldering / brazing only, after


749



d) All the above leads shall then be clamped tightly with cotton twine directly on to the special frame/bracket making “Pie” shape connection. This structure could be made up of Bakelite/ Permalli wood/ laminated PC board flats, having minimum size of 25x6.0 mm. Line leads leading to the HV bushing terminals shall be directly clamped to the horizontal support bar of the “Pie” structure so that any tension which may develop in the HT leads due to jerks or at the time of making the connection , is not passed to the HT coils.


B) LV Winding :

a) LV connection shall be taken out by cut on the top yoke channel duly reinforced to compensate for the mechanical strength.


c) LV star point shall be formed of copper flat of sufficient strength. Leads from winding shall be connected to the flat by brazing.

d) Firm connection of LV winding to bushing shall be made of adequate size of “ L shape flat”. Connection of LV coils to L shape flat shall be by brazing only.


750

f) Neutral of the Secondary winding (LV) shall be brought out to a separate insulated bushing .

g ) For Copper windings, silver brazing rods with suitable flux will be used. 16. CORE CONSTRUCTION & CORE COIL ASSEMBLY DETAILS:

A . CRGO CORE





(v) Flux density at rated voltage and frequency of core and yoke shall not be more than 1.6 Tesla. The Over fluxing shall be limited to 12.5% of rated value and flux density at 112.5% of rated voltage does not exceeds by 1.9 Tesla.


751



t between s in mm


(B). AMORPHOUS METAL CORE a) The core shall be high quality amorphous ribbons having very low loss formed into wound cores of rectangular shape, bolted together to the frames firmly to prevent vibration or noise. The complete design of core must ensure permanency of the core loss with continuous working of the transformers. The value of the flux density allowed in the design shall be clearly stated in the offer. Curve showing the properties of the metal shall be attached with the offer.

b) Core Clamping – Amorphous Metal and CRGO wound core Transformers



2% 5%

Width of axial duct in mm in between insulating cylinder Radial ducand HV coil


5 4 8

752

1. Core clamping shall be with top and bottom U-shaped core clamps made of sheet steel clamped with MS tie rods for efficient clamping.

2. MS core clamps shall be painted with varnish or hot oil resistant paint

3. Suitable provision shall be made in the bottom core clamp / bottom plate of the transformer to Arrest movement of the active part.


d) Flux density should not be more than 1.6 Tesla for Amorphous core. No load current shall not exceed 2% of full load current and will be measured by energizing the transformer at 433 volts 50 c/s on the secondary. Increase of voltage of 433 volts by 12.5% shall not increase the no load current disproportionately high and shall not exceed i.e., 5%. Test for magnetic balance by connecting the LV phase by phase to rated phase voltage and measurement of an, bn, cn voltage will be carried out.






753

Sr. No.

Item Particulars







4 MS Channels of 100x50x6t mm. size (applicable for CRGO transformers)





2. IPDS / TN No:

3. Rating:


In case if above marking is not found on the core assembly of physically opened transformer selected for physical verification during final inspection then no further inspection shall be carried out and re-inspection charges shall be payable by the supplier.

754


(a) Transformers tank shall be rectangular in shape, robust in construction and with adequate strength to withstand the pressures developed at the time of severe fault conditions. The tank body shall be suitably stiffened to achieve the object. The tank sheet shall be electrically welded both from inside and outside to impart proper mechanical strength and to plug leakage of oil. All joints of tank and fittings shall be oil tight and no bulging shall occur during service. The tank design shall be such that the core and windings can be lifted freely. The tank plates shall be of such strength that the complete transformer when filled with oil may be lifted bodily by means of lifting lugs provided. The stiffeners shall be welded full length. All the welding shall be continuous. The top cover plate shall be sloping down by more than 15 mm, opposite LV bushings side. The top cover shall be extended by 5 mm by all the sides beyond the flange of the top cover. Accordingly length of the lifting hooks shall be extended. The top cover shall have no cut at point of lifting lug. No negative tolerance in the tank dimensions is acceptable in actual supply. The tank shall be fabricated by welding at corners. No horizontal or vertical joints in tank side walls and its bottom and top cover will be allowed.


Sr. No.

I T E M S Parameters







500 KVA rating 2 Nos.

7 Size of M. S. stiffener (mm)

500 KVA rating 50x50x 6 angle

755





10t mm flat

12 Tank Base Channel (ISMC Type) at a C-C distance of 415 mm)

500 KVA rating 2 (125x65x6t mm

* Tank base channels shall be provided parallel to the bushing lines. NOTE: Each cover bolt shall be complete with two flat washers, one nut and one spring washer.

I. The 12 Nos. nuts & bolts ( 4Nos each on length sides & 2 nos each on widths sides of tank body) to be tag welded on top cover / tank body of the transformer.

II. The 04 Nos. Anti Theft Fasteners shall be provided - one each on all four sides in centre of body of transformer. Two holes shall be provided – one on top cover and other on collar of transformer to facilitate providing of 2 Nos. poly-carbonate seals on longitudinal side.





756










Sr. No.


Bottom Cover (mm)

Side of Tank

(mm)

1 315 KVA Three Phase

5.0 5.0 4.0


For example:

Weight of 315 KVA Transformer Tank

1200 Kg. (approx.)


757




(c ) Lifting Lugs: Four Nos. welded heavy duty lifting lugs of MS plate of 10mm thickness, suitably reinforced by vertical supporting flat welded edge wise below the lug on side wall shall be provided, these shall be so extended that cutting of bent plate is not required


i) The gasket provided in between top cover plate and tank shall be of min. 6 mm thick neoprene rubberized oil resistant cork sheets conforming to type B or C as per IS 4253 part II


iii) Height of the tank shall be such that minimum clear height is to be achieved between top of yoke and under side of the tank cover (with gasket in place) as under:

a) 500 KVA rating - 100 mm iv) All screws, nuts, bolts and fasteners exposed to atmosphere are as per IS 1180

Part-1/2014 as follows :-


-------------

100

758

a) Size 12 mm and below:- stainless steel Above 12 mm:- Steel with suitable finish like electrogalvanized with passivation or hot dip galvanized



vi) Talbros make neoprene/nitrile based rubberized cork sheet – grade RC-70-C shall only be used as gasket material. Alternatively, other makes of gaskets having type designations as under can also be used, if ‘Talbros’ make gasket is not available:









Steel surface shall be prepared by sand / shot blast or chemical cleaning including phospating, as per IS 3618. Inside of tank Oil shall be painted with varnish or oil resistance

759

paint. For external surface, one coat of thermo-setting powder paint or one coat of epoxy primer followed by 2 coat of polyurethane base paint of olive green colour confirming to shade No. 220 of IS: 5-1961 to be applied in order to distinguish of star level transformers. Total Dry film thickness as per IS 1180 Part-1 2014




Inside

Outside

01 01



c) Hot Oil Paint

Outside

Outside

Inside

01

02

01

All steel screws, nuts, bolts and fasteners exposed to atmosphere as per IS 1180 Part-1/2014.




a. Earthing terminals of M12x40L/ 4/8x1.5” with tinned lugs and symbol – (2 Nos.) b. Lifting lugs – (4 Nos. for main tank). c. Rating and terminal marking plate (non-detachable), details to be included

760

in one plate only. The plate shall be of stainless steel only, with details clearly marked - (1 No.)

d. Bi-metallic terminal connectors on HV bushings and L-type connectors on LV bushing shall be fitted before dispatch.

e. Oil level gauge of minimum 150 mm length of prismatic glass, indicating three positions of oil, marked as follows, shall be provided:

1 -5 °C - Min.

2 30 °C - Nor.

3 90 °C – Max.

f. Silica Gel Breather shall be aluminium/ metal – (1 No.) g. Thermometer pocket, 12.5 mm dia with cap. shall be provided –– (1 No.)

h. Oil filling hole (1/¼”dia) with cover and gun metal drain valve of 20 mm size on the oil conservator.

i. a) One filter valve of gun metal of 20 mm size at the top side of the tank.

b) One drain cum sampling cum filter valve of Steel at the bottom side of the tank but opposite of the top filter valve. The necessary arrangement for locking on this valve by providing MS Sheet box duly welded on tank body shall be made.

c) The valve shall be either of Leder or L&T or AUDCO make and wheel type.

j. HV Bushings. These shall be of 17.5 KV/250 A class, porcelain/ polycrate with non adjustable, single gap type arcing horns – (3 Nos.)

k. LV Bushings. 1.1 KV class: (4 Nos.)

a. 1000 A (M 30 stem) – for 500 KVA rating.

l. Brass rod 12 mm diameter for HT Terminals of each rating – (3 Nos.)

761

m. Brass rod for LT Terminals of each rating – (4 Nos.)

a. 30 mm diameter for 500 KVA rating transformer

n. 100 mm dial type thermometer for oil temperature indication.

o. Two pulling eyes one each on opposite side of the tank.

p. Explosion vent (pressure relief valve ) and pipe connected with conservator.

q. Air release device.

Note:-

1. As mentioned above, suitable bi-metallic connectors on HV bushing and L-type connector shall be provided, having capacity of about 1.5 times the rated current of the transformer

2. LV/ HV Connector shall not be the integral part of the bushing stems”.

19. CONSERVATOR:

When a conservator is fitted, the oil gauge and the breathing device shall be fixed to the conservator. In addition, the cover of the main tank shall be provided with a self-sealing pressure release device designed to operate at minimum pressure of 8 PSI (0.564 Kg./cm. Sq.) to enable release of air trapped within the main tank, unless the conservator is so located as to eliminate the possibility of air being trapped within the main tank. The conservator shall be of cylindrical shape and it should be provided above the HV bushing with a minimum clearance of 50 mm and suitably inclined to maintain the clearance.

The total inner volume of conservator shall be minimum of 10% of the volume of oil

in each rating of transformer. The inside diameter of the pipe connecting the conservator to

a main tank shall be min. of 50 mm and it should be projected into conservator in such a

way that its end is approximately 25 mm above the bottom of conservator so as to create a

sump for collection of impurities. The min. oil level (corresponding to – 5 deg. C.) should be

762

above the sump level. The connecting pipe from conservator tank to main tank shall have a

sloping flap so that oil falling from pipe shall not fall directly on the active job.

The oil filling hole cap of conservator should be welded with tank body with the help

of suitable inverted ‘U’ shape clamp.

i. SILICAGEL BREATHER:




The transformer shall be provided with outdoor type 3 Nos. 17.50 KV / 250 A class porcelain bushings, conforming to IS:3347/1972 & IS:2099/1973 from the manufacturer of repute. The HV bushings shall be on top of the tank and shall be fitted on a pocket made on top cover. These pockets shall be such that the HV bushing is tilted more towards the HV side. The bushing of R & B may also be tilted sidewise to maintain the required electrical clearance. The bushings rods and nuts shall be made of brass. The inner porcelain portion of the bushing shall be projected about 50% of the length inside the bushing pocket. HT bushing(s) mounting bolts should be tag welded.



763


“LV Bushing side shall be on side of the tank but opposite to the HV Bushing side. 4 Nos. LV Bushings (1.1 KV/ 1000 A for 500 KVA rating transformers) shall be mounted on the tank wall. Projection of the LV pocket shall be such that inner portion of the LV stem shall not project more than 20 mm inside the tank, to facilitate unhindered lifting of the core coil assembly. Bushing stem of M 20 & M 30 size shall be of brass respectively. Rest of the components shall conform to the requirement of IS:3347 (Part I/section 2). The LV bushings shall be of reputed make such as JSI, JAIPUR GLASS, BPPL Bikaner, Baid Sanitary Works, Bikaner, Agarwal salt Co. Bikaner, or any other make approved by the purchaser. The LV bushings shall generally conform to IS: 3347 and IS: 7421”.






A) Rating & terminal marking plate: Each Transformer shall be provided with non detachable name, rating and terminal marking plate fitted in a visible position. All details shall be given on one plate. Material of the plate shall be stainless steel only. Thickness shall be 0.9 mm (with a tolerance of ±0.1 mm). The plate shall be made absolutely undetectable either through welding or riveting or through any other approved method.

Each HV & LV terminal shall be duly marked with its terminal numbers. (e.g. HV terminal with capital letter 1U, 1V, 1W and LV terminal by corresponding small letters) 2u, 2v, 2w and the neutral terminal by 2n). In the diagram to be given on the name plate, the relative position of various terminals- when viewed from top – shall be clearly shown.

764

Inspection shall not be undertaken unless all these details are verified by the Inspecting Officer.


I. P.O. No. - month & year. II. IPDS/TN

III. Sr. No. of transformer. IV. Date of despatch - month & year V. Date of expiry of guarantee period – month & year

VI. Maximum Guaranteed Loss Figures at 50% and 100% loading VII. Recommended fuse sizes for HV & LV sides.

VIII. Name & Full address of the manufacturer. IX. Capacity of the transformer. X. Rating of the transformer.

XI. Energy Efficient level-1 and Standard IS1180 Part-1 ALL DETAILS ON THE NAME RATING AND DIAGRAM PLATE SHALL BE INDELIBLY MARKED

i.e. BY ENGRAVING, STAMPING or PUNCHING.

B) Identity Plate :- A M.S. plate of size 75 x 75 x 2.5 mm shall be continuously welded to the main tank body below the middle HV bushing and in clearly visible position, with following details clearly punched :


……… KVA , S.NO. ……….

……….MAKE …………….

C) Identification Mark :- In addition to above, the following identifying details shall be clearly punched on top cover near lifting lug, towards neutral side, with minimum 10 mm x 10 mm size punch letters.

MAKE

Sr. No.

IPDS/TN



765

I. Make II. IPDS/TN No.

III. Sr.No. D) To punch the details make, TN No. & Sr.No.of transformer at two places ( i.e. at the

top cover & transformer tank). The punching shall be distinct and visible. E) Technical Plate- In addition to existing provision of identity plate and name plate

one plate also be affixed on the transformer mentioning the following details:-

a. Name of the Firm b. IPDS/TN No. c. Make d. Rating e. Core :-


f. LV Coil :- i. ID/OD Dimensions ii. Conductor Size

g. HV Coil :- i. ID/OD Dimensions ii. Conductor Size

h. Limb Centre i. Window Hight


TRANSFORMERS:

Guaranteed Technical particulars of the transformers offered shall be furnished in A-4 size paper by the Tenderer in the proforma appended herewith at Schedule-A. Complete details shall be furnished. Tolerances on weight quantity and dimension figures shall be ± 5% at the tender stage, subject to maintaining the minimum electrical clearances as per the specification. However, no negative tolerance shall be allowed on the short circuit type tested design. Electrical performance data shall be subject to tolerances as per ISS, unless otherwise specified in this specification. However, the Total losses at 50% & 100 % loading shall be maximum guaranteed without any positive tolerance.


The bidder shall furnish type test certificates of offered design / similar design, wherever available, with the bid.


766


i. Name rating / diagram plate drawing. ii. Outline and general arrangement drawing. iii. Core-coil assembly drawing. iv. Core section (for limb and yoke) along with flux density calculation

sheet / drawing. v. Cooling area calculation sheet. vi. Thermal Ability short circuit calculation sheet. vii. Core loss and magnetization curves of the laminations. viii. Heat dissipation calculations (heat dissipation by tank walls excluding

top and bottom should be 500 W/sq.meter.



The tenderer shall furnish the details type tests conducted on the Transformers offered to supply



( i ) The inspection and testing shall be conducted as per relevant clause of the

General Conditions of Contract (Section-II) at the place of manufacture. The transformers shall be completely assembled and tested at the factory. The inspection may be carried out by the purchaser at any stage of manufacturing. The supplier shall grant free access to the purchaser’s representative at all reasonable times when the manufacturing work is in progress. Inspection and testing of any material under this specification by the purchaser shall not relieve the supplier of his obligation of supplying the material in accordance with the specification and shall not prevent subsequent rejection if the material is found to be defective.


reasonable facilities, without charge, to satisfy him that the material is being manufactured in accordance with the specification. The bidders must have adequate set of instruments for conducting testing as per ISS/ Specification. The instruments for measurement of losses shall be of accuracy class of 0.5 or better. The instruments shall be duly calibrated and

767

Calibration Certificate should not be older than one year on the date of presentation to the Inspecting Officer. The calibration shall be arranged from NABL accredited testing house. A comprehensive list of testing equipment/ instruments indicating make, Sr.No., type, class of accuracy, calibrating agency, calibration date etc. should be furnished alongwith the bid. The calibrated instruments shall be duly sealed by calibrating agency to avoid any tampering with calibration and the details thereof shall be clearly mentioned in the Calibration Certificate(s).





A) 100% testing of the Distribution Transformers shall be carried out at firm’s works for measurement of total load losses at 50% & 100 % loading. Remaining testing shall also continue to be carried out as per practice.

All the assembled/ finished transformers prior to despatch shall be subjected to routine tests as per IS:2026. Minimum 25% of the offered lot size samples subject to minimum 5 Nos will be taken for routine and acceptance tests. The supplier shall invariably furnish manufacturer’s routine test certificate along with inspection call of the offered transformers for pre-despatch inspection. The inspection offers without furnishing of routine test certificates as per ISS of all the transformers offered for final inspection shall not be entertained, and any delay on this account shall be to firm’s account.









loading). 8. Measurement of No load current at 100 % and 112.5% of rated voltage and normal

frequency.

768

9. Checking of rating and terminal marking plate. 10. Pressure Test (As per IS 1180 Part-1:2014)










unit of 500 KVA Transformers unit

I. Over Flux Density Test (in the first lot and may be repeated in subsequent lots if desired by purchaser).

II. Measurement of unbalance current. (See note below) III. Magnetic Balance Test (See note below) IV. Oil Leakage Test (See note below)

Fifteen days clear notice shall be arranged for pre-despatch inspection by purchaser’s representative as per General Conditions of Contract.

After successful inspection, the inspecting officer shall seal each and every

transformer by sealing the transformer with 2 Nos. poly-carbonate seals on longitudinal side as per the manner mentioned in Clause No. 17 above. Before sealing, the inspecting officer

769

will ensure that all the offered transformers are completed and duly fitted with name, rating and diagram plate, identification plate (on tank body & Top cover) as specified in this specification.


i) INSULATION RESISTANCE MEASUREMENT:


20

Deg.C. 30Deg.C.

40Deg.C

50Deg.C.

60 Deg.C.

11000 Volts (HV)

800 400 200 100 50

433 Volts (LV)

400 200 100 50 25

ii) MAGNETIC BALANCE TEST:





Apply 250 Volts between LV terminals-2u-2n and measure voltages between 2v-2n & 2w –2n.

Apply 250 Volts between 2v-2n and measure voltages between 2u-2n & 2w-2n.

Apply 250 Volts between 2w-2n and measure voltages between 2u-2n & 2v-2n.


iii) OIL LEAKAGE TEST ( As per IS 1180 Part-1/2014): The oil leakage test shall be conducted on one unit selected from the offered lot .The

assembled transformer for non-sealed and sealed Type with all fittings including bushing in position shall be tested at a pressure equivalent to twice the normal head measured at the base of tank for 8 hrs. There should be no leakage at any point.

31. TYPE TESTS:

770

The bidder shall furnish valid type test certificates of same rating of offered item from a Govt. approved / Govt. recognized / NABL Accredited laboratory / ILAC i.e. International Laboratory Accredited Laboratory (in case of foreign laboratory). Such type test certificates should not be older than 5 years as on the date of opening of tender. For this purpose date of conducting type test will be considered. Type test conducted at supplier’s own NABL accredited lab shall not be considered. The following Type Test shall be conducted on one unit at NABL/Govt. Approved Lab(Details of Test given in the specification )



Measurement of total losses (at 50% & 100% loading): After pre-dispatch inspection of material at firm’s works, the dispatch instructions will be issued for the respective store(s) as per requirement of Nigam. Sample(s) will be drawn from the lot(s) received in store(s) and will be subjected to the following test(s):

a. One transformer will be selected out of every lot of 10 Nos. or part thereof for measurement of No load Losses at rated voltage; No Load current (at 100% and 112.5% of rated voltage); Impedance voltage, thickness of tank body sheet and total Losses at 50% and 100% loading at rated current. The testing shall be arranged either at purchaser’s own testing lab and / or at independent test lab. The testing charges for such tests shall be borne by the purchaser. The test results will be applicable to the respective lot of 10 Nos. from which sample was drawn.

b. In case if dispatch instructions are less than 10 Nos. than one sample shall be selected from each store (s) and the test result so obtained shall be for the quantity consigned / received by the store (s).

The percentage impedance voltage at rated current shall not exceed the permissible limit as specified with allowable tolerance failing which the sub lot of transformers represented by the sample shall be rejected. The transformers selected for total Losses shall also be subjected to magnetizing current and in case found beyond the limit, the lot shall stand rejected.


771

One sample out of 100 Nos. transformers or part thereof shall be selected for physical verification/ checking of window height, limb centre and checking of insulation of HV and LV windings at CTL.

NOTE:


If the window height and limb centre are found more than 7.5 mm, then apart from rejecting the lot, firm’s balance order would be cancelled and such firms shall not be awarded any order for one year or in next tender of tendered rating to be opened / finalized whichever is later. However, a tolerance of ± 2mm shall be allowed in window height and limb centre.


33 GUARANTEE PERIOD: Ia) For Out of Rajasthan State Firms



772








IPDS/TN

KVA

Sr.No.

Date of supply

Date of failure

Date of repair


773

Guarantee period

extended.



iv) All due care should be taken to ensure that the original name plate and identification

plate provided should not be removed from the position at which they are fixed originally. In case it is felt that these are loose then it should be repaired suitably by welding or riveting.


vi) G.P. repaired Distribution may be got tested at CTL as per the sampling plan of new transformer except the physical opening test. The 10% tolerance (as per IS:2026 part –I/1977) be allowed on total losses at 50% and 100% loading for the transformers failed under guarantee period for testing at firms’ works as well as in CTL testing.


NOTE:- Firm shall keep the records for at least 8 years of transformers supplied by them & Payments shall be made only after receipt of successful test report from our Central Testing Laboratory (CTL) on the samples selected from the material received at the stores.

774

Schedule-A

GUARANTEED TECHNICAL PARTICULARS

500 KVA (Cu) WOUND ,11 / 0.433 KV DISTRIBUTION TRANSFORMER

S. No.


500 KVA1. Manufacturer’s Name and Address





(b) L V


(b) L V

7. Rated Frequency

8. No. of phases


(b) L V




775

S. No.


500 KVA (a) Of top oil by thermometer



14. Max. guaranteed No Load loss,at rated voltage and rated frequency

15. Total losses at rated current and at 75 ° C


16.















776

S. No.


500 KVA20. Maximum efficiency










HV

LV





(d) IS reference




(c) IS reference

777

S. No.


500 KVA29. H V coil constructional details:-

(a) type of winding






(g)Current density

(h)Coil I. D

(i)Coil O.D












(h)Current density

778

S. No.


500 KVA (i) Coil I. D.

(j) Coil O.D.




(n) Weight of covered conductor per transformer

(o) Inter layer insulation (p) No. of vertical spacers per circle












(h)Phase to phase Clearance

between Limbs (HV Conductors), with a

779

S. No.


500 KVA minimum of 2 Nos. x 1mm Press board

covering the tie rods





(i) Length

(ii) Breadth

(iii) Height


(i) Sides

(ii) op

(iii) Bottom



the tank (ii) Size




attached?


35. Core Details

780

S. No.


500 KVA(i) Size of core frame channels



(iv) Core coil assembly base supports ( 2 Nos )







(c) Oil weight





(a) Length

(b) Breadth

(C )Height


(Signature)

Name & Designation


781

TECHNICAL SPECIFICATION FOR HT & MIP SHEET METAL METER BOXES 1.1 SCOPE :

This specification provides for the design, manufacture, stage inspection and testing before dispatch, supply and delivery of sheet metal meter boxes specified herein for their satisfactory operation. The HT meter box shall be suitable for floor mounting and MIP meter box for wall mounting as per requirement indicated in the drawings. The wall mounting of MIP meter boxes shall be achieved by providing four (4) grouted studs on the walls, two of them will be inside the meter box and two will be outside the meter box as shown in the attached general arrangement drawing. The mounting holes of the boxes must be accessible without removing any non-metallic sheet.

1.2 It is not the intent to specify completely herein all the details of the design and

construction of equipment. However, the equipment shall conform in all respects to high standards of engineering, design and workmanship and shall be capable of performing in continuous commercial operation up to the bidder's guarantee, in a manner acceptable to the purchaser, who will interpret the meanings of drawings and specification and shall have the power to reject any work or material which in his judgment is not in accordance therewith. The offered equipment shall be complete with all components necessary for their effective and trouble free operation. Such components shall be deemed to be within the scope of bidder's supply irrespective of whether those are specifically brought out in this specification and/ or the commercial order or not.

2.0 STANDARDS :

2.1 The meter boxes shall conform to the following Indian Standards which shall mean

latest revisions, amendments/changes adopted and published, unless otherwise specified hereinafter.

S.No. Indian Standard Title

1. IS:14772- 2000 General requirement for enclosure for accessories for household and similar fixed electrical installations.2. IS:1852 - 1985 Specification for rolling & cutting

tolerances for hot rolled steel products3. IS:2036 - 1974 Specification for Phenolic laminated

sheets (superseding IS:2038-1962).4. IS:4820 - 1968 Specification for Thin vulcanized fibre

sheets for electrical purposes. 5. IS:808-1989 Specification for MS Channel (ISMB)

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3.1 GENERAL TECHNICAL REQUIREMENTS:

REQUIREMENT FOR SHEET METAL METER BOXES:

a) STANDARD:

The meter boxes along with the doors shall be fabricated out of MS sheet of fine quality and thickness as per relevant drawings attached and capable of withstanding the mechanical, Electrical and Thermal stresses as well as the effects of humidity which are likely to be encountered in the services and at the same time ensuring the desired degree of safety. The same shall comply in all respect with the requirement of latest IS:14772(2000) for "Boxes for enclosure of electrical accessories". In case of any discrepancy between write-up and drawings attached, the details given in drawings will prevail. The bill of material as indicated in the drawings shall be covered in the scope of supply.

All sides of the box will be fabricated out of M.S. sheet of fine quality. The two

sides and rear one will be fabricated out of one single sheet. Top and bottom will be in one piece each from one M.S. sheet, which will be continuously welded from inside to form a complete box. The door will be in two parts for HT meter box and in one part for MIP meter box which shall be fabricated out of M.S. sheet(s). Each door will be fixed with the box with inside hinges in such a way that door hinges can not be removed from out side. The doors shall be provided with handle. The door shall be provided with a lining of minimum 5mm thick felt in order to make it dust proof.

The door shall ensure reasonable safety against the spread of fire. They should not be ignited by thermic over-load of live parts housed by the box.

b) SEALING ARRANGEMENT :

The doors shall also be provided with sealing arrangement from out side by fixing

30x9 mm long , bolts at the top and bottom and the Hexagonal nuts as per arrangement shown in the enclosed drawings. These bolts shall be welded on the collars in such a manner that the fly nuts can be tightened from outside. These bolts should possess hole of 2 mm as in the center of the head from where the sealing wire shall pass and the meter boxes can be sealed properly. The doors will further be provided with a felt lining of 5 mm in order to make it dust proof.

c) EARTHING OF METER BOX :

The earthing bolts of size 35x9 mm made of hot dipped G.I. with four plain 1.2 mm

thick G I washers, one G I spring washer and two G I nuts on either side of the box shall be provided as shown in the drawing for earthing of meter box. The earthing bolts provided in the meter box on both sides should have arrangement that the bolts cannot be loosened and removed from out side. The bolt should have the cottar pin arrangement.

d) INCOMING AND OUTGOING CABLE ARRANGEMENT :

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Two holes at the bottom just below the cable fixing bracket shall be provided for entry & exit of cable . Holes of 50mm dia shall be provided for fixing cable as shown in the drawing.

e) WINDOW GLASS

One unbreakable transparent sheet of toughened/triplex glass of thickness 6 mm for window of required size will be provided on the upper door as per arrangement indicated in the drawing so that the meter inside the box can be read easily. The glass sides shall be lined up with V-shaped rubber gasket of 1mm thickness. This glass shall be fixed inside the box in a projected groove. The glass assembly shall be secured with a zinc passivized rectangular MS frame screwed at four corners.

f) WORKMANSHIP

The fabrication of material shall be done in such a way that there is a good finish of fabricated material. The material shall be fabricated accurately to adhere to dimensions as per attached drawings. Holes must be perfectly circular and dimensional tolerance as given below shall be permissible. The box should be fabricated/welded such that the rain water does not enter into it.

g) TOLERANCE :

The sheet metal boxes shall be subjected to a maximum of plus-minus one percent(+/-1%) tolerance on the overall dimensions and –ive rolling tolerance for sheet metal boxes shall be as per IS:1852/1985 & IS 513-1994 with latest amendment(s).However there shall be no limit for +ive tolerance in thickness. The rolling tolerance for nonmetallicbakelite base sheet shall be as per IS:2036/1995 with latest amendments. The tolerance in weight of meter box shall not be more than plus three percent and minus zero percent(+ 3% & - 0%).

h) Painting/Protection against corrosion :

The box(es) shall be adequately protected against rust, dust and corrosion both

from inside and outside.

All sheet steel work shall be phosphated in accordance with IS:6005 code of practice for phosphating iron and steel.

Oil, grease, dirt and swarm shall be thoroughly removed by emulsion cleaning .

Rust and scale shall be removed by pickling with dilute acid followed by washing

with running water rinsing with slightly alkaline hot water and drying. After phosphating thorough rinsing shall be carried out with clean water followed by final rinsing with dilute dichromate solution and oven drying.

After phosphating the cabinet must be painted by electrostatic method only (powder coating) and the minimum coating should be 50 microns. The colour shade shall be 631 of IS - 5.

i) GUARANTEED TECHNICAL PARTICULARS :

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The tenderer shall furnish all the necessary information as desired in the schedule of GTPs at Annexure-(A & B) of this specification. If the tenderer desires to furnish any other information in addition to the details as asked for, the same may be furnished against the last item for each type of box of this schedule.

EMBOSSING:

The following information shall be clearly/ indelibly embossed on the meter boxes made of MS sheet.

i) J.V.V.N.L (on the top of the door.)

ii) Manufacturer's trade name iii) TN- ---/IPDS. (at the bottom of the door.) iv) Sign of Danger (in upper side of front door) v) H.T./M.I.P. Meter box


4.2 HT METER BOXES :

a) GENERAL TECHNICAL REQUIREMENT:

The HT metering cubicle dimensions shall be 1500 mm height x1350 mm width as viewed from front side and 1250mm depth as viewed from lower side and 300 mm depth as viewed from upper side. The box shall be suitable for housing following items :

i) 11 KV CT/PT Unit.

ii) Electronic/Static Trivector meter : iii) Testing Terminal block

The cubicle shall be fabricated out of MS sheet of fine quality having thickness 1.6mm. The thickness of the Sheet for cubicle door shall also be 1.6 mm. The cubicle shall be fabricated out of or not more than five pieces of the M.S. Sheet(s).

i) Bottom 1250mm x 1350mm x 3 mm - 1 No.ii)

iii) Rear 1000mm x 1350mm Top 1750mm x 1350mm (without any joint)

- 1 No.- 1 No.

iv) Side members 1250 width - 2 Nos. x1000mm height upto 950 mm width and for next 300 mm width height is 1500mm i.e.(1250 x 1000 + 450 x 500 in all)

All above pieces should be minimum 1.6mm thick except bottom which is 3mm thick.

785

There should be no joint in the above pieces. All the members shall be welded with continuous welding from inside to form a complete cubicle, since the thickness of sheet is 1.6mm.Looking to the weight of HT meter box which is about 210 kg. or as per approved prototype sample’s weight.MS plate of 5 mm thick with a hole of 50 mm dia shall be at both sides of the HT meter box. The top cover sheet shall be slopping by 10 to 25 mm towards backside of the box. 2 nos.M.S channels of size 75x40 mm with length of 1100 mm (front to rear) shall be provided at the bottom of the box to avoid direct contact of the box with floor which will also provide ease in handling and during fixing on the plinth.

b) DOOR:

The door shall be in two parts fabricated out of 1.6 mm thick MS Sheet. Each door shall be fixed with the box with three inside hinges. The left hand side door shall be provided with handle and the right hand side door shall be provided with built-in system of one handle to open and close the doors and to engage vertical M.S. Rods for keeping the doors in close position but without lock and key facility. A window as per size indicated in drawing shall be provided on right hand side door of the box.

c) SEALING ARRANGEMENT :

One `L' shape 25 mm MS strip of thickness 3 mm on both doors as shown in the

drawing shall be welded from inside for sealing purpose.

The door shall also be provided with sealing arrangements from its outside by fixing studs as per drawing at the top & bottom with Hexagonal nuts to tighten & to keep the doors in closed position. The size of the cut outs for the windows shall be as shown in drawing.

d) ADDITIONAL DOOR WINDOW :

i) One additional door with window as per separate drawing shall be required to

be provided with the box such that

a) meter will not be accessible physically without opening the door of the box. b) it will not allow any external object to enter into the box. c) it will have separate sealing arrangement as per drawing. d) the meter shall be readable from outside through a unbreakable transparent

sheet of toughened/ triplex glass of thickness 6 mm for window of required size will be provided on the upper door as per arrangement indicated in the drawing so that the meter inside the box can be read easily.

e) Opening for push button mode display (as per drawing)

The window of this additional door shall be provided with toughened / triplex glass by securing the same with the help of a rectangular M.S. frame which can be tightened through 4 Nos. nut bolts of appropriate size. The 4 bolts shall be welded inside the door from its head such that the nuts can be tightened to secure the rectangular frame. The glass sides shall be fixed inside the box in a projected

786

groove. This additional door shall also be required to be provided with sealing bolts with holes and hexagonal nuts as shown in drawing

This door shall be provided with 2 nos. suitable size hinges from inside such that the hinges are not visible from outside. This door shall be provided with U-shaped rubber gasket along the edges of the door.

e) EARTHING OF BOX :

The earthing bolt on each side of the cubicle shall be provided as shown in the drawing. The earthing bolts provided in the meter box on both side should have arrangement such that the bolts can not be loosened and removed from outside. The bolts should have the cottar pin arrangement.

f) CABLE ENTRY/EXIT :

Two holes at the bottom just below the HT cable fixing bracket shall be provided for entry and exit of 11 KV cable.The size of the hole shall be 80mm for HT cable for 25A to 200A rating. The cable entry and exit holes should be fitted with metallic glands for proper closing and sealingafter installation of the cable. Hole of 60 mm dia on 1350x100mm sheet near the bakelite sheet for fixing TTB for 4 sq mm cable (3nos) from CTPT secondary box.to TTB.

g) TEST TERMINAL BLOCK :

The HT metering box shall be provided with three phase four wire Link type

meter test terminal block (TTB) of VEECO/CAPITAL make. NON - METALIC BAKELLITE BASE SHEET :

One non-metallic Bakelite sheet having size 400x400x4.5mm shall be provided for mounting meter. Another non- metallic bakelite sheet of size 300mx400mm shall be provided for fixing TTB. The supply shall include such sheets as per relevant ISS. The sliding arrangement of bakelite for fixing meter shall be continuous key type of size 25x25x3mm.

4.3 MIP METER BOXES :

TECHNICAL REQUIREMENT

a) GENERAL :

The MIP metering cabinet dimensions shall be 1100x625x375mm as per enclosed drawing and shall be suitable to house the 3 phase static meter in the upper compartment and current transformers ( Resin Cast Bar Type) in the lower compartment. Both the compartments will be separated by a portion of 1.6 mm thick MS Sheet. The cabinet shall be suitable for wall mounting.

The box shall be fabricated out of 1.6mm thick MS sheet of fine quality. The two sides and rear one will be fabricated out of one single sheet of minimum 1.6 mm thick. Top & bottom will be in one piece each from 1.6 mm MS sheet which will be

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welded from inside to form a complete box. The top cover sheet shall be slopping by 15mm to 20 mm towards back side of the box. The approximate weight of the meter box will be more than 46kgs. or as per approved prototype sample’s weight.

b) DOOR

The door will be fabricated in one piece out of 1.6 mm sheet. M S angle of size of 25x25x3mm should be welded on the back of the door at ABCDE as per drawing enclosed at a distance of 20mm from rubber lining. The door shall be fixed with the box with two inside hinges. The door shall be provided with handle. The door shall also be provided with sealing arrangement from outside by fixing stud at the top middle & bottom and hexagonal nuts . These studs should possesshole of 2mm as in center of the head from where the sealing wire shall pass & meter box can be sealed properly. The door will further be provided with a lining of 5mm thick felts in order to make it dust proof. The door shall be provided with window with additional door having size as per relevant drawing will be provided on the door so that the meter inside the box shall be read easily. Four fixing clamps, two at top side and two at bottom of the meter box for fixing the box on wall.

c) CABLE ENTRY/ EXIT

Two holes of 50mm dia shall be provided for fixing cable as per drawing. The cable entry and exit holes should be fitted with metallic glands for proper closing and sealing after installation of the cable.

d) ADDITIONAL DOOR WINDOW :

i) One additional door with window as per separate drawing shall be required to be provided with the box such that

a) Meter will not be accessible physically without opening the door of the

box.

b) It will not allow any external thing to enter into the box.

c) It will have separate sealing arrangement as per drawing.

d) The meter shall be readable from outside through a unbreakable transparent sheet of toughened/ triplex glass of thickness 6 mm for window of required size provided on the upper door as per arrangement indicated in the drawing so that the meter inside the box can be read easily.

e) Opening for push button mode (as per drawing)-

The window of this additional door shall be provided with toughened/ triplex glass by securing the same with the help of a rectangular frame which can be tightened through 4 nos. nut bolts of appropriate size. The 4 bolts shall be welded inside the door from its head such that the nuts can be tightened to secure the rectangular frame. This glass shall be fixed inside the box in a projected groove. This additional

788

door shall also be required to be provided with sealing bolts with holes and hexagonal nuts as shown in the drawing. This door shall be provided with 2 nos. suitable size hinges from inside such that the hinges are not visible from outside. This door shall be provided with u-shaped rubber gasket along the edges of the door.

e) MOUNTING OF NONMETALLIC BASE SHEET :

The box shall be provided with 4 rectangular brackets of size mentioned in the

drawing so as to fix bakelite sheet to mount the meter on it at a distance of about 50mm from the rear wall on which the meter & CTs will be fixed. The supply shallinclude bakelite sheet as per ISS.

f) ARRANGEMENT OF CT MOUNTING :

The primary terminal P1 of CTs shall be mounted on porcelain supports bolted on three Nos. The other side of CT (P2) shall also be mounted on another three Nos. porcelain supports/clits. The position should be adjusted by sliding clits to & fro horizontally as per the requirement of primary terminals of CTs.

g) PARTITION PLATE

There shall be one partition plate at the height of 700mm from the bottom of the box to facilitate 4 Nos. CTs

5.1 TESTS :


The tenderer must indicate clearly about the various testing facilities for

routine/acceptance tests as per relevant ISS is respect of Meter Box as are available at their works. In case no testing facilities are available at the tenderer's works particulars of the place where such testing is proposed to be conducted during the course of inspection must be indicated.

5.3 TEST VALUES :

For all acceptance tests, the acceptance values shall be the values guaranteed by the bidder in the guaranteed technical particulars or the acceptance value specified in this specification or the relevant standard whichever is more stringent.

5.4 ADDITIONAL TESTS :

The purchaser reserves the right for carrying out any other tests of a reasonable

nature at the works of the supplier/laboratory or at any other recognized laboratory/ research institute in addition to the above mentioned acceptance and routine tests at the cost of the purchaser to satisfy that the material complies with the intent of this specification.

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5.4.1 TYPE TESTS :

Tests carried out to prove conformity with the requirement of the standard. These are intended to prove the general qualities & design of a given type of product.This test shall be carried out on two sample of enclosure for accessories of the same type selected preferably at random from a regular production lot. Before commencement of tests, the sample shall be visually examined & inspected for obvious visual defects in respect of component, part and their assembly, construction, marking, mechanical hazards, earthing etc. The external surface finish shall be even and free from finishing defects.

The following tests as per IS: 14772/2000 shall constitute the type test:

S.No.Tests

1. Marking 2. Dimensions 3 . Protection against electric shock4. Provision For earthing5. Construction 6. Resisting to aging,to humid condition, ingress of material. 7. Mechanical Strength8. Resistance to heat9. Resistance to rusting.

Criteria of acceptance: Both samples shall successfully pass all type tests for providing conformity with the requirements of the standard. If any of the sample fails in any of the type tests, the testing authority, at its discretion, may call for fresh sample not exceeding twice the original number and subject to all tests or to the test(s) in which failure(s) occurred.

5.4.2 ACCEPTANCE TESTS :

The following tests shall constitute the acceptance tests :-

Tests

1. Marking 2. Dimensions 3. Protection against electric shock 4. Provision for earthing 5.. Construction

The verification of above tests shall be arranged by the supplier in the presence of

purchaser’s inspecting officer at the time of inspection. 5.4.3 ROUTINE TESTS:

The tests at s.no.(3) and (4) in the Cl.5.3.2 shall constitute this test as per IS:14772/2000.

790

6.1 INSPECTION & TESTING :

The inspection and testing shall be carried out by the purchaser's representative as per provisions of relevant ISS, specification & GTP

a) The supplier shall arrange fifteen days advance notice to enable the purchaser

to depute the inspecting officer for conducting necessary testing at supplier's works. Any delay beyond fifteen days in arranging the inspection shall be to the purchaser's account.

b) In case the manufacturer does not have adequate facilities for getting all the

required tests conducted in his laboratory, the purchaser at his option may get these tests conducted in any reputed testing laboratory. All the expenses for such tests to be conducted outside shall be borne by the supplier.

c) In case material/equipment is not found ready by the representative of the purchaser

deputed for inspection to the extent of the quantity indicated in the inspection call with tolerance of (-) 10% or if the inspection is not got carried out by any reasons on account of the supplier the re-inspection charges shall be`7,500.00 for the supplier works located in Rajasthan and ` 15,000.00 for the supplier works located outside Rajasthan will become payable by the supplier on this account to the Accounts Officer (MM) JVVNL, Jaipur.

d) The Acceptance tests shall be carried out as per relevant ISS Latest Amended) ,

P.O. , GTP and the proto type sample approved by this office .For acceptance tests samples from the offered quantity for inspection shall be selected by inspecting officer as per provisions of IS:14772/2000 (Latest amended).

e) The inspection may be carried out by the purchaser's representative at any stage of

manufacture/before dispatch as per relevant standard. Inspection and acceptance of any material under the specification by the purchaser, shall not relieve the bidder of his obligation of furnishing material in accordance with the specification & shall not prevent subsequent rejection if the material is found to be defective. The bidder shall keep the purchaser informed in advance, about manufacturing program so that arrangements can be made for inspection.

f) The purchaser reserves the right to insist for witnessing the acceptance /routine testing of the bought out items. The bidder shall give 15 days advance intimation to enable the purchaser to depute his representative for witnessing the acceptance and routine tests. The inspection charges would be to the purchaser's account.

7.1 TEST REPORTS :

i) All records of routine test reports shall be maintained by the Supplier at his works for periodic inspection by the Purchaser.

ii) All test reports of tests conducted during manufacture shall be maintained by

the Supplier. These shall be produced for verification as and when requested for by the Purchaser.

791

8.0 PACKING &FORWARDING : The HT and MIP meter boxes shall be suitably packed in order to avoid damage during transit and handling.

.

792

ANNEXURE-A

STATEMENT OF GUARANTEED TECHNICAL PARTICULARS AND

OTHER DETAILS FOR HT METER BOXES

S. NO. Particulars

1 (a)

Name & address of / firm / bidder.

b) Work's complete address of manufacture

2 Dimensions of Box in mm

3 Thickness of M.S.Sheet in mm

a) For three sides, top & door

b) For bottom.

4 Dimensions of Bakelite/ Acrylic sheet in mm.

a) Sheet for mounting meter.

b) Sheet for mounting TTB.

c) Sheet on the top side of CT-PT Chamber

d) Sheet on both sides.

e) Sheet on back sides.

f) Transparent Acrylic sheet.

5 Window/window door details :

a) Inner dimension of window

b) Window door dimension.

c) Viewing window dimension.

d) Acrylic sheet size for window.

e) Metal frame for fixing acrylic sheet

i) Inner dimensions.

ii) Outer dimensions.

6 Dimensions of sealing/earthing bolts in mm.

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a) Door sealing bolts.

b) Earthing bolts.

7 Approximate weight of complete Box in Kgs.

8 Details of painting.

9 Shade No. of colour/paint.

10 Tolerance in fabrication :

a) In overall dimension.

b) Rolling tolerance.

11 Dimensions of fixing brackets in mm.

12 Details of Test Terminal Block (TTB)

a) Make. (Capital/Veeco)

b) Rating.

c) Type. (Link Type)

d) Whether extended cover provided ?

13

Embossing details.

JVVNL

Trade mark of manufacturer

TN-------/IPDS

Sign of danger

HT meter box

14 Dimensions of felt lining to make box dust proof

15 Details of drawing

16 Size of base channel for HT box.

Signature

Name & designation

With seal of the bidder

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ANNEXURE-B

STATEMENT OF GUARANTEED TECHNICAL PARTICULARS AND

OTHER DETAILS FOR MIP METER BOXES

S. No. Particulars

1 (a) Name & address of / firm / bidder.

b) Work's complete address of manufacture

2 Dimensions of Box in mm

3 Thickness of M.S.Sheet in mm

a) For three sides, top & door

b) For bottom.

4 Dimensions of Bakelite/ Acrylic sheet in mm.

a) Sheet for mounting meter.

b) Sheet for cleats

5 Window/window door details :

a) Inner dimension of window

b) Wndow door dimension.

c) Viewing window dimension.

d) Toughened/triplex glass

e) Metal frame for fixing acrylic Sheet

i) Inner dimensions.

ii) Outer dimensions.

6 Dimensions of sealing/earthing bolts in mm.

a) Door sealing bolts.

b) Earthing bolts.

7 Approximate weight of complete Box in Kgs.

8 Details of painting.

9 Shade No. of colour/paint.

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10 Tolerance in fabrication :

a) In overall dimension.

b) Rolling tolerance.

11 Dimensions of fixing brackets As per drawings in mm.

12

Embossing details.

JVVNL

Trade mark of manufacturer

TN-------/IPDS

Sign of danger

MIP meter box

13 Dimensions of felt lining to make box dust proof.

14 Details of Bus bar cleats

15 Details of drawing

Signature

Name & designation

With seal of the bidder

796

TECHNICAL SPECIFICATION FOR SUPPLY OF 11 KV XLPE INSULATED ALUMINIUM CONDUCTOR AERIAL BUNCHED CABLES ALONGWITH ACCESSORIES FOR WORKING VOLTAGE UPTO & INCLUDING 11000 VOLTS

1.SCOPE:

This specification covers manufacture, testing before dispatch, supply of HT Aerial bunched XLPE insulated aluminium cables twisted over a central high strength bare aluminium alloy messenger wire for use in the area of Jaipur Discom. Accessories as specified in this specification are also covered in the scope of this specification.

The bidders should be a manufacturer of offered Item. The bidder must possess valid ISI License for IS:7098(Pt-II)/1985.

1.2 RATED VOLTAGE:

The rated voltage of the cables shall be 6.35 KV / 11KV and the maximum operating voltage shall be 12KV.

1. STANDARDS:

Unless otherwise stipulated in this specification the following standards with latest amendments shall be applicable. Any departure from the Standards be indicated in Schedule-III.

i) IS:7098(Pt.II)/ : Cross Linked Polyethylene 1985 Insulated PVC Sheathed for working Voltage from 3.3KV upto & including 33KV.

ii) IS:10810/1984 : Methods of test for cables.

(Series)

iii) IS:8130/1984 : Conductors for insulated cables.

797

iv) IS:10418/1982 : Drums for Electric Cables

v) IS:398(PT-4)/1994 : Aluminium alloy conductors.

vi) IS:5831/1984 : PVC Insulation & sheath of Electric Cables.

vii) IS:14255/1995 : Aerial Bunched Cable for working voltage upto & including 1100 V.

viii) IEC:502 :


i) Maximum temperature attainable 60 deg.C by an object exposed to sun.

ii) Maximum average ambient 40 deg.C temperature in a 24 hours period

iii) Minm. ambient air temperature (-)5 deg.C iv) Maximum relative humidity. 100% v) Average number of thunder 40

storm days per annum. vi) Average number of rainy days 100

per annum. vii) Average annual rainfall 10 to 100 cm

viii) Number of months of tropical 4 months monsoon conditions.

ix) Maximum wind pressure. 100kg/sq.mm. x) Altitude not exceeding 1000 M


The Single Core HT Aerial Bunched Cables shall consist of XLPE insulated aluminum conductor twisted over a central high strength aluminum alloy bare messenger wire and the Three Core HT Aerial Bunched Cables shall consist of three XLPE insulated aluminium conductors twisted over a central high strength bare aluminium alloy messenger wire for use as 11KV over-head lines. The principal parameters of Aerial Bunched Cable shall be in accordance to IS:7098(Pt.II)/1985, IS:8130/1984 & IS:398(Pt.IV)/1984 (latest amendments, if any) and as enumerated in subsequent clauses.

798

4. GENERAL TECHNICAL REQUIREMENTS :

5.1 The Phase Conductor shall be of round, stranded & Compacted Circular Aluminium of nominal cross-sectional area as per as per latest IS. The corresponding nominal conductor diameter and number of wire in the conductor shall be as per relevant IS:8130/1984. The insulated phase conductors shall be twisted over a central bare aluminium alloy messenger wire which shall carry the weight and take all the mechanical stress. The messenger wireshall also serve the purpose of earth wire.

5.2 The cable shall be suitable for use where the combination of ambient temperature

and temperature rise due to load, including temperature on exposure to direct sunlight results in conductor temperature not exceeding the following:

Type of Insulation Normal Continuous Operation

Short Circuit Operation

Cross Linked Polyethylene 90 DEG.C. 250DE

6 MATERIAL:

6.1 PHASE CONDUCTOR :

The conductor shall be composed of aluminium wires complying with the requirements of Class-2 grade of IS: 8130/1984 or latest amendment, if any.

6.1.1 CONDUCTOR SCREENING (as per IS: 7098(Pt.2):

The conductor screening shall be provided over the conductor as per Clause No. 10.1 of IS: 7098(Pt.2)/1985 with extruded semi conducting XLPE material (Tapes are not acceptable).

The minimum thickness of conductor screening shall be 0.5 mm.

6.1.2 INSULATION:

The conductor (with protective barrier or screen where applied) shall be provided with Cross Linked Polyethylene Insulation applied by EXTRUSION as per Clause No11.1 of IS: 7098(Pt.2)/1985 amended up to date. The cross-linked polyethylene insulation shall conform to the requirement given in Table-I of IS:7098(Pt.2)/1985.The thickness of insulation shall be as per Clause No.11 of IS:7098(Pt.2)/1985 as below:

S.No Nominal Area of Phase Conductor

Nominal Thickness (mm)

Minimum Thickness (mm)

1 95 Sq.mm 3.6 3.14

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6.1.3 INSULATION SCREENING: The insulation screening shall consist of two parts namely Metallic & Non- Metallic

a) Non-Metallic part shall be applied directly over the insulation of core and shall consist of extruded semi conducting XLPE material. The Minimum thickness of Non-Metallic screening should be 0.6 mm.

b) Metallic part shall consist of EC grade Copper tape having thickness of 0.05 mm with minimum 10% overlapping be applied over non-metallic part.

6.1.4 OUTER SHEATH:

The outer sheath shall be of Polyethylene (PE) Grade ST-7 of IEC-60502-2 applied by EXTRUSION. Outer sheath shall be suitable to use at UV exposure weather and shall contain Carbon Black contents 2.5% +/- 0.5% in well dispersed manner.

The Nominal Thickness & Minimum Thickness of outer sheath shall be as specified below:

S.No. Nominal Area of Phase

Conductor Nominal

Thickness(mm)Minimum Thickness (mm)

1 95 Sq.mm 2.0 1.4

6.2 MESSENGER CONDUCTOR:

The Aluminium Alloy (Al + Mg + Si) stranded conductor containing approximate 0.5 percent magnesium and approximately 0.5 percent silicon conforming to IS:398(Part-4)/1994 or latest amendment, shall be of heat treated to get desired Mechanical & Electrical properties.

The Messenger Conductor shall be either stranded circular or compacted circular type and shall have minimum strands as per IS: 398(Part-4)/1994. The surface of the conductor shall be smooth to avoid damage of outer sheath.

There shall be no joints in any wire of the messenger conductor except those made in the base rod or wires before final drawing. The direction of outer layer of wires in messenger conductor shall be right hand. The Messenger Conductor should carry the weight of Aerial Bunched Cables under specific site conditions.

800


The phase conductors shall be provided with one, two or three `ridges' as shown in Fig.1 of IS:14255/1995 for quick identification. The messenger conductor shall not have any identification mark.

6.4 ASSEMBLY (LAYING UP):

Assembly lay length shall not exceed 40 times of sheath phase core diameter.The direction of lay shall be right hand.

7. TESTS: TYPE TESTS:-

The material offered, shall be fully type tested as per relevant standard of specification of IS:7098 (Part-II/1985) amended up to date. The bidder must furnish type test reports of similar rating & design of material at Schedule-A. The following shall constitute type tests:


i) Annealing test (for copper) ii) Tensile test (for aluminium) iii) Wrapping test (for aluminium) iv) Resistance Test

b) Test on Messenger Conductor: (as per IS:14255/1995)

i) Breaking load test for messenger conductor. ii) Elongation test for messenger conductor. iii) Conductor resistance test

c) Tests for thickness of insulation and sheath.

d) Physical tests for insulation:

i) Tensile strength and elongation at break. ii) Ageing in air oven. iii) Hot Set test

801

iv) Shrinkage test. v) Water absorption (gravimetric).

e) Physical test for outer sheath: (as per IS:14255/1995)

i) Tensile strength and elongation at break. ii) Melt Flow Index

iii) Vicat softening test. iv) Carbon Black:

a) Contents. b) Dispersion

v) Environmental Stress Cracking.

f) Partial discharge test. g) Bending test. h) Dielectric power factor test:

i) As a function of voltage. ii) As a function of temperature.

i) Insulation resistance (volume resistivity test). j) Heating cycle test. k) Impulse withstand test. l) High voltage test. m) Flammability test. n) Any other test as per relevant IS.

The tenderer must also clearly indicate various testing facilities available at their

works for testing the material as per relevant standards. In case of otherwise particulars of the place where such testing is proposed to be conducted during the course of inspection shall be indicated with the offer.


The inspection may be carried out by the purchaser at any stage of manufacturer .The successful tenderer shall grant free access to the purchaser's representative at a reasonable time when the work is in progress. Inspection and acceptance of any equipment/material under this specification by the purchaser shall not relieve the supplier of his obligation of furnishing equipment in accordance with the specification and shall not prevent subsequent rejection if the equipment/material is found to be defective. The following Acceptance tests as per Clause No.18.2 of IS:7098(Part.II)/1985 & IS: 14255/19955 shall be conducted in presence of the purchaser's authorized representative / agency on each lot of offered cables:

802

i) Tensile Test (If applicable).

ii) Wrapping Test (If applicable).

iii) Conductor Resistance Test ( Phase Conductor & Messenger).

iv) Breaking load test for messenger conductor.

v) Elongation test for messenger conductor.

vi) Test for thickness of insulation & sheath.

vii) Hot Set Test for XLPE Insulation. viii) Tensile strength & elongation at break test for insulation and

outer sheath. ix) Carbon Black:

a) Contents. b) Dispersion

x) Partial Discharge Test (for screened cables only). xi) High voltage test and xii) Insulation resistance (Volume resistivity)Test.

The following shall constitute optional test:-

Bending test on complete cable:

The test shall be performed on a sample of complete cable. The sample shall be bent around a test mandrel at room temperature for at least one complete turn. It shall then be unwound and the process shall be repeated after turning the sample around its axis by 180 degrees.

The cycle of these operations shall then be repeated twice. The diameter of the mandrel shall be:

Where:

10(D+d)

803

D= actual diameter of the cable, for example, minimum circumscribing diameter mm ; and

d= actual diameter of the phase conductor ,mm.

Requirement: No cracks visible to the necked eye are allowed.

8.1 TEST:- The following shall constitute routine tests. The tests shall be done as per relevant ISS:

a) Conductor resistance test b) Partial discharge test c) High voltage test. d) Messenger Resistance

8.2 The bidder shall furnish Packing list of Cable mentioning serial Nos. of Drums, length in each drum, gross weight of drum without lagging and requisite Accessories alongwith inspection offer duly signed by the authorized representative of the firm, failing which offer shall not be entertained. The purchaser reserves the rights to insist for witnessing the acceptance / routine tests of the bought out items.

8.3 At least 5% of total numbers of drums subject to minimum of two (2) in the lot put up for inspection shall be selected at random to ascertain the length of cable by the following method.

“At the works of manufacturer of the cable shall be transferred from one drum to another for checking any manufacturing defects in the cable, at the same time measuring its length with the help of the graduated pulley and cyclometer. The difference in average length thus obtained from the declared length by the supplier in the packing list shall be applied to all the drums if the cable is found short during checking the sample lot (s).”


8.5 The calibration certificate(s) should not in any case be older than one year at the time of presenting the same to the inspecting officer/ inspecting agency of the purchaser. The testing instruments/ equipments should be duly sealed by the Calibrating Agency and mention thereof shall be indicated in the calibration certificate(s).

804

8.6 SAMPLING:

8.6.1 The number of samples to be selected shall depend on the number of drums in the lot. Sampling for conducting acceptance tests shall be in accordance to Clause No.18.2.1 of IS:7098(Pt.2)/1985 which is briefed as under:

SCALE OF SAMPLING:

Samples shall be taken and tested from each lot for ascertaining the conformity of the lot to the requirements of the specification.

The number of drums (n) to be selected from the lot of drums (N) of consignment of cables shall be in accordance with column 2 and 1 of the following Table respectively. The samples shall be taken at random.

be used.

In order to ensure the randomness of selection, random number tables shall

Defectives.

Number of Drums to be selected for Sampling and Permissible Number of

805

SPEC-TN- -

Number of Drums in

the Lot Number of Drums to be taken as Sample

Permissible Number of Defectives

(1) (2) (3) N n a

Up to 25 3 0 26 to 50 5 0 51 to 100 8 0 101 to 300 13 1 301 & Above 20 1


i) Sample drums from the material received at stores shall be selected for testing at CTL as per sampling plan given hereunder in presence of firm’s representative. The selected sample drum / drums shall be transported to CTL by concern S.S / ACOS of Nigam.

ii) The selected sample drum for CTL testing shall be identified by the seals provided by Inspecting Officer / Inspecting Agency during pre-dispatch inspection at firms works and these sealing details shall be invariably mentioned in the selection Memo by the nominated officers of Nigam.

iii) The tests in the Nigam Testing laboratory (CTL) shall be conducted in the presence of representative of supplier for which a 7 days notice shall be issued through Fax / Speed Post stating Date & Time to the firm, so that supplier can depute their representative to witness the test . In case the supplier or his representative does not turn up the testing shall be proceeded & completed.

for mandatory test checking on the samples to be selected from material received at Nigam’s stores by officers to be nominated by Circle SE’s / SE (I&S) for testing at CTL.

iv) SAMPLING:


v) TESTS: The following tests shall be carried out as per relevant clause of latest IS on each selected drum by drawing sample of 10 Mtr. at CTL from random distance during re-winding. The following tests shall be carried out :

806

SPEC-TN- - a) Rewinding test (Measurement of Length) & Checking of Manufacturing

defects. b) Measurement of Resistance of conductor (Phase & Messenger). c) Tensile strength & Elongation at Break Test for Insulation & Sheath d) Test for Thickness of Insulation & Sheath e) Hot Set Test f) Breaking load test on messenger wire. g) Verification of Marking



a) If the measured of conductor resistance of the sample(s) exceeds beyond 2% as per the resistance specified in the contract, the material shall be rejected and the same shall have be replaced by the supplier.

b) If the measured conductor resistance of the sample(s) exceeds the value specified in the contract but does not exceed by more than 2% of the resistance value specified in the contract, the material contained in the lot / sub-lot to which the sample belongs shall be accepted with a deduction @ 1.5% of the cost of cable for increase in resistance for every 1% or part thereof.

c) If the sample(s) fails in any other test, the material shall be rejected and shall have to be replaced by the supplier.

TEST CHARGES :


9.0 IDENTIFICATION:

9.1 The manufacturer shall be identified throughout the length of cable as per Clause No.20.1 of IS:7098(Part.2)/ 1985.

9.1 The cable code employed shall be as per Clause No.20.3 of IS:7098 Part.2)/1985.

9.2 The cable shall be identified through out the length of the cable by legend XLPE 90.

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SPEC-TN- - 9.4 In order to distinguish these electric cables from telephone cables the word

“ELECTRIC” shall be indicated, printed or embossed through the length of cable on outer surface.

10.0 EMBOSSING:

The cable shall also be required to be embossed with the word `Name of manufacturer or Trade name, ELECTRIC/ Voltage Grade/JAIPUR DISCOM/IPDS/TN, cable code, size of cable & year of manufacture at every meter length for which no extra charges shall be paid.

11.1 PACKING AND MARKING:

11.2 The cable shall be wound on a non returnable wooden drum conforming to IS:10418/1982 of suitable size and packed. The ends of cables shall be sealed by means of non-hygroscopic sealing material. Only one cable length shall be supplied on a drum. The cable can also be supplied on M-Steel Drums as per relevant ISS as applicable.

11.3 The cable drums shall carry the following information either stenciled or painted.

i. Manufacturer's name, Brand or trade mark. ii. Type of cable and voltage grade. iii. Number of cores. iv. Nominal cross-sectional area of the Conductor. v. Cable Code. vi. Length of cable on the drum. vii. Direction of rotation of drum (by means of an arrow). viii. Gross mass. ix. Year of manufacture. x. IPDS/tender No. and xi. Name of Consignee & Full destination. xii. Date of expiry of Warranty /Guarantee Period.


12.1 The cable shall be supplied in standard length of 500 Mtrs in one Drum for size 3CX95+95 Sq.mm .

12.2 A tolerance of (+/-) 5% shall be allowed on standard length.

12.3 Shorter length not less than 50% of standard length shall be acceptable to the extent of 2% of ordered quantity in each size.

808

SPEC-TN- -

13.0 GUARANTEED TECHNICAL PARTICULARS :

The bidder shall furnish guaranteed technical particulars

14.0 DRAWINGS & DOCUMENTATIONS:

The tenderer is required to furnish the detailed constructional drawing of cable & other details of cable. The calculations of weights of different components of the cable shall also be furnished.The drawing of drums shall also be furnished as per relevant applicable ISS.

15.1 MANDATORY TOOLS:

The bidders are required to supply essentially the following mandatory tools free of cost, the quantity of which is indicated against each:

i) Hydraulic Crimping Tool suitable for Size 50 Sq.mm. to 400 Sq.mm. - One Set per 5 Km. of AB Cable.

ii) Pulley for A.B.C. : One Set per 5 Kms. of A.B Cable.

The Pulley is used to receive high voltage Aerial Bunched Cables. HT Aerial Bunched Cable fixing on poles and is ensured by a 1.20 Mtrs. strap in order not to stress the Pulley during cable unwind.

16.0 TRAINING:

After supply of 1st Lot of material the bidder will have to train the personnel of

JVVNL, procedure for laying / erection of HT Aerial Bunched Cable alongwith required Accessories in the Circle free of cost i.e the purchaser shall not bear any charges for this training.

809

Schedule-A

TYPE TEST CRITERIA:- The bidder shall furnish valid and authenticated type test certificate from a Govt.

approved / Govt. Recognized / NABL Accrediated laboratory / ILAC i.e. International laboratory Accrediation Corporation (In case of foreign laboratory)/ of similar rating and design of tendered material / equipment.


The bidder should furnish documentary evidence in support of the laboratory whose type test have been furnished, that the said laboratory is a Govt. / a Govt. approved / a Govt. recognized / NABL accredited laboratory / ILAC accredited (in case of foreign laboratory).


810

TECHNICAL SPECIFICATION FOR ACSR DOG CONDUCTOR ----------------------------------------------------------------------------------------------------------------

1. SCOPE 1.1 This section provides for manufacture, testing before dispatch and supply of

Aluminum Conductor, Galvanized Steel reinforced (ACSR) for satisfactory operation in various lines and sub-stations. The conductor should conform to latest IS.

1.2 Aluminum Conductor with galvanized Steel re-enforcement shall be conforming to IS: 398(Pt.2)/1996 with latest amendments if any, supplied on non returnable strong wooden drums generally conforming to IS: 1778/1981 (Latest).

The bidders should be a manufacturer of offered Conductor. The Offers from

sole selling agents / authorized dealer shall not be entertained. The firms (manufacturers) must posses valid ISI License for the offered Conductor. 2. CLIMATIC CONDITIONS:

i) Peak ambient temperature 50 deg.C

in shade.

ii) Maximum average ambient 40 deg.C temperature in a 24 hours period in shade.

iii) Min. ambient air temperature in shade (-) 5 deg.C

iv) Maximum temperature attainable 60 deg.C

by an object exposed to sun.

v) Maximum relative humidity. 100%

vi) Average number of thunder 40 storm days per annum.

vii) Average number of rainy days 100 per annum.

viii) Average annual rainfall 10 to 100 cm

ix) Number of months of tropical 4 months

Monsoon conditions.

x) Maximum wind pressure. 100 kg/ sq. mm.

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xi) Altitude not exceeding 1000 M

3. GENERAL TECHNICAL REQUIREMENT OF ACSR DOG CONDUCTOR:

The technical particulars shall be furnished strictly in the Performa attached at Schedule- -A of this specification. The specific values must be indicated against each column and no 'dash'. 'dot', 'blank' or as per IS word should be indicated in this schedule. The technical suitability shall be adjudged from the values furnished in the clause 3.2 “PRINCIPAL PARAMETERS”.

The ACSR conductor shall comply in all respect with IS: 398(Part.2)/1996 with latest

amendment, if any from the date of its applicability. 3.1 MATERIAL

The material offered shall be of the best quality and workmanship. The conductor

shall be constructed from hard drawn aluminum and galvanized steel wires which have the mechanical and electrical properties specified in Tables 1 & 2 of IS:398(Part.2)/1996 with latest amendment, if any, The Zinc coating on the galvanized steel wires may be applied in accordance with IS:4826/1979 with latest amendment if any. The EC Grade Aluminum rods for use in the manufacture of Aluminum Wires shall conform to IS:5484/1978 amended up to date. The zinc used for galvanizing shall be Electro type High Grade Zinc not less than 99.95 percent purity. It shall conform to and satisfy all the requirements of IS:209/1992 amended up to date. Galvanized Steel Wire should comply mechanical properties as per Table 2 of IS:398 (Part.2)/1996 amended up to date. The chemical composition is as per Annexure-C of IS:398 (Part.2)/1996 amended up to date.


The details of ACSR Dog conductor are tabulated below:-

PARTICULAR ACSR DOG a) Stranding and

wire diameter (mm) 6/4.72 Al. 7/1.57 St.

b) Number of strands Central Steel wire Aluminum

7 6

c) Sectional area of Aluminum (Sq. mm) 105

d) Total Sectional area (Sq. mm) 118.5

e) Overall diameter (mm) (Approx.) 14.15

f) Weight (Kg/Km) (Approx.) 394.00

812

g) Calculated max. DC resistance at 20 Deg. C (Ohm./ Km.)

0.2792

h) Approx. calculated breaking load (KN) 32.41

i) Modulus of elasticity (GN/Sq. meter) 75

j) Coefficient of liner Expansion per deg C. 19.8x10-6

3.3 The details of aluminum strands are as follows:

PARTICULAR ACSR Dog

a) Min. Breaking load of strand before stranding (KN)

2.78

b) Min. Breaking load of strand after stranding (KN)

2.64

c) Max. D.C. Resistance of strand at 20 Deg. C (ohm/Km.)

1.650

d) Diameter mm Nominal Minimum Maximum

4.72 4.67 4.77

e) Mass (Kg/Km.) 47.30

3.4 The details of steel strands are as follows:

PARATICULAR ACSR Dog

i) Min. Breaking load of strand before stranding (KN)

2.70

ii) Min. Breaking load of strand after stranding (KN) 2.57

iii) Diameter mm b) Nominal b) Max./Min

1.57

1.60/1.54

iv) Zinc coating testing 2 dips of 1 min. each

v) Min. weight of zinc coating GM/ Sq. Mtr. 180.50

813

3.5 Tolerance on normal sizes:

The tolerance in diameter of aluminum wires and steel wire used in the

manufacture of ACSR shall be allowed as per IS: 398/ (Part-2) /1996 amended up to date.

3.6 Stranding :

3.6.1 The wires used in the construction of a galvanized steel reinforced aluminum conductor shall before stranding, satisfy all the relevant requirements of this specification and relevant IS.

3.6.2 The lay ratio of the different layers shall be within the limits given:

S. No.

Particulars ACSR DOG

1 Number of wires : a) Aluminum b) Steel

6 7

2 Ratio of aluminum Wire diameter to Steel wire dia-meter

3

3 Lay ratio for aluminum Wires (Outer most layer): a) Minimum b) Maximum

10 14

4. Lay ratio for steel core (6 wire layer) a)Minimum b) Maximum

13 28

NOTE: For the purpose of calculation, the mean lay ratio shall be taken as the arithmetic mean of the relevant minimum and maximum value given in this table.

vi) Mass of strand at normal diameter of strand(Kg./Km.)

15.10

814

4. TESTS (FOR ACSR DOG CONDUCTOR):

TESTS BEFORE DESPATCH: The ACSR Dog Conductor shall be subjected at manufacturer’s works before dispatch, to the tests mentioned here-under as per IS: 398 (Part-2)/1996 with latest amended.

4.1 ROUTINE TESTS:

The following tests shall be conducted before and after stranding on each drum of

the conductor by the manufacturer at his works as per relevant standard IS: 398 (Part-2)/ 1996 (latest amended)

a. Visual & dimensional check on drum as per specification.

b. Visual check for joints, scratches etc. and length of conductor by re-winding of

conductor on empty drum as per Specification/ IS.

c. Measurement of dia-meter of individual Aluminum and steel wires. (Clause-13.2)

d. Measurement of Lay Ratio. (Clause-13.8)

e. Breaking load of individual wires (Clause-13.3.1)

f. Ductility Test (Clause-13.4)

g. Wrapping Test (Clause-13.5)

h. Resistance Test (Clause-13.6)

i. Galvanizing Test (Clause-13.7)

j. Any other test as per relevant IS

4.2 ACCEPTANCE TESTS:-

The following tests shall be conducted on samples taken at random from a lot as per relevant standard IS: 398 (Part-2)/1996 (Latest amended) in presence of purchaser’s representative:-

a. Visual & dimensional check on drum as per specification.

b. Visual check for joints, scratches etc. and length of conductor by re-winding

of conductor on empty drum as per Specification / IS.

815

c. Measurement of dia-meter of individual Aluminum and steel wires. (Clause-13.2)

d. Measurement of Lay Ratio. (Clause-13.8)

e. Breaking load of individual wires (Clause-13.3.1)

f. Ductility Test (Clause-13.4)

g. Wrapping Test (Clause-13.5)

h. Resistance Test (Clause-13.6)

i. Galvanizing Test (Clause-13.7)

5.0 TYPE TESTS :-

For ACSR Dog Conductor, the bidders shall furnish the type test report along with

bid as detailed at Schedule-) as per relevant IS:398 Pt.2)/1996 with latest amendment along with bid only for those tests which are not covered under acceptance test.

6.0 SAMPLING PLAN:

6.1. Samples for Acceptance Tests: Samples shall be taken as per relevant IS i.e. IS-398 (Part-2)/1996 with latest version as the case may be.

6.2 Apart from the sample selected for carrying out Acceptance Tests at the

works of the firm during inspection, one more sample from each length be also selected out of one drum under re-winding for carrying out various Acceptance Tests as per relevant IS. If any of the sample so selected from each length failed in any acceptance test the entire lot under inspection is not acceptable.

6.3 TOLERANCE ON TEST RESULTS:

Tolerance on test results shall be allowed as per relevant IS/Spec. whichever is

more stringent. 7.0 INSPECTION

7.1 (a) The conductor shall be manufactured in accordance with latest edition of IS: 398(Part.2)/1996 with all subsequent amendments issued from time to time for ACSR Dog Conductor. All the tests as laid down in the above mentioned specification on individual aluminum wire and steel wire shall be carried out. The testing shall also include

816

the tests on manufactured finished conductor. Moreover the supplier shall also furnish test certificate(s) of raw materials to the inspecting officer at the time of inspection. The inspection & testing shall be governed by Clause No.1.27 of Section-II (General Condition of Contract).

(b) The supplier / manufacturer must offer conductor for inspection through a letter

of offer mentioning size and quantity of the conductor along with Packing List duly signed indicating drum Serial No. individual lengths total length, net weight & gross weight in DUPLICATE. This letter of offer shall be addressed to this office. The packing list shall also be furnished to the Inspecting Officer prior to carrying out the inspection at the works.

(c) The Manufacturer shall provide all adequate facilities at his works for

inspection of at least one number conductor drum or 5% conductor drums offered for inspection whichever is higher selected at random by the authorized representative of the purchaser for checking / verification of conductor length/ manufacturing defects by transferring the conductor from one drum to the another empty drum and at the same time measuring the length and lay ratio of each conductor length so transferred by means of the standard calibrated and sealed meter.

(d) If the firm is not having the necessary facilities for carrying out the required

tests as per relevant IS / Purchase Order, the supplier will arrange such testing facilities in some other Government laboratory and shall bear the cost so incurred. But in such cases firm shall inform to the purchaser in advance before commencement of supplies.

(e) The supplier shall provide adequate facilities for weighment of all the drums

offered for inspection.

7.2 In case of testing after re-offering as per Clause No.15 of IS:398 (Part.2)/1996 the lot under reference will be subject to 100% checking, if required by the purchaser.

7.3 The supplier shall present the latest Calibration Certificate(s) of testing instruments / equipments to be used for the testing of the material covered in the Purchase Order to the authorized inspecting officer / inspecting agency of the purchaser. The testing instruments / meters/ apparatus etc. should be got calibrated by the supplier from time to time from Govt. Lab or Independent test laboratory / house having valid accreditation from National Accreditation Board for Testing and Calibrating Laboratories for the testing equipments or original manufacturer having traceability to NABL / NPL or equivalent accredited lab.


817

7.4 The manufacturer will provide certificates as per the Clause No.7 of IS: 398((Part.2)/1996 “Freedom from defects" and clause No.9 “Joint in Wires" of IS:398 (Part 2) /1996 for ACSR Conductors and the certificates as per Clause No.6.

8.0 STANDARD LENGTH & VARIATION IN LENGTHS:

8.1 The ACSR Dog Conductor shall be supplied in the standard length. The

standard length of ACSR Dog Conductor shall not less than the value specified below with a tolerance of (-) 5%. More than the standard length shall be acceptable.

- b) ACSR DOG - 1000 Mtrs.

- 8.2 Short length(s), if any shall not measure less than 80% of standard length as

specified above in any case. The total quantity of such short length(s) shall not exceed 5% of the quantity of the lot offered for inspection.

8.3 The maximum permissible length per drum shall be as under subject to

condition that the manufacturer while packing the conductor in drum shall ensure that after winding complete quantity of conductor in drum a uniform space of not less than 100 mm. remains between outer layer of conductor and inner surface of the external protective lagging of the drum. This is essential to ensure that the conductor does not get closer to the lagging and to avoid damaged during transportation/ reeling / unreeling or rolling on the undulated ground / fields:

b) ACSR DOG --- 2.4 Kms.

9.0 PACKING FORWARDING AND MARKING:

9.1 The packing shall have to be done as per standard practice worthy of road

transport. The conductor shall be wound in strong wooden drums so as to withstand all stresses due to transportation, handling and stringing operation so that there is no damage caused to the conductor during the process of these operations. The wooden drums shall be non-returnable and shall generally conform IS:1778/1981 with latest amendments, however, the main parameters of the drum shall be as under:

818

S.NO. PARTICULARS DIMENSION FOR ACSR DOG CONDUCTOR

1. Flange Dia 1250 mm (+/- 5%) 2. Flange

Thickness 2x25 mm (+/- 5%)

3. Barrel Dia 500 mm (+/- 10 mm) 4. Traverse 510 mm (+/- 10 mm) 5. Number of Bolts 4 Nos. 6. Dia of Bolts 12 mm 7. Bore Dia 80 mm

However, use of seasoned wood shall not be insisted, provided wood used should be of good quality to withstand transportation hazards. The drums shall be having inside flanges painted with Aluminum Paint and with Ordinary White Enamel paint from outside. The conductor on each drum shall be securely fastened at each end. The outer end of the conductor shall be fastened inside the drum against one of the sides of the flanges while it is under tension and shall be such that no looseness is transmitted to the internal layers. The conductor shall be snugly, tightly and uniformly spooled on the drums. The wrapping of conductor on the drums shall be laid snugly against side of the preceding wrap and the first and last wrap in each layer shall fit snugly against the sides of the flanges. Drums shall be lagged with sufficient strong wooden laggings to support the full drum without crushing. The wooden drums after providing lagging shall be fastened by two steel wires of min. 3 mm. Dia over the lagging on the two sides of adequate size to keep the lagging intact and to prevent the drum from crushing/ damage.

Although the various dimension of the drums such as flanges, stretches,

traverse and barrel diameter shall depend on the quantity of conductor as offered and agreed upon, on one drum. The manufacturer while packing the conductor in drum shall ensure that after winding complete quantity of conductor in drum a uniform space of not less than 100 mm. remains between outer layer of conductor and inner surface of the external protective legging of the drum. This is essential to ensure that the conductor does not get closer to the legging and to avoid damaged during transportation/ reeling / unreeling or rolling on the undulated ground / fields.

9.2 Water proof material shall be wrapped round the barrel and inner surface of flange before winding the conductor and also wrapped round over the conductor completely wounded and under the laggings.

9.3 The drums shall be marked clearly in block letters with water proof mark

having the marking attached to them so that there is no possibility of goods being lost or wrongly dispatched due to faulty marking. The marking shall constitute the following:-

a) Name & full address of the consignee. b) Destination station.

819

c) Serial number of drum. d) Size of Conductor with its code name. e) Total length of Conductor in drum, with individual length (s). f) Number of length(s) in each drum. g) Gross mass of drum including the tare mass of drum. h) Tare mass of the empty drum with lagging. i) Net mass of conductor. j) BIS standard mark. k) Name of the supplier. l) IPDS/TN number.

m) Date of expiry of warranty / guarantee period.

Besides above, an arrow shall be put on the drum so as to indicate the direction in which the drum can be unwound. The manufacturer shall also provide his own lead seal with distinguishing mark at the outer end of the conductor on each drum before dispatch of the material.


I. Sample drums from the material received at stores shall be selected for testing at CTL as per sampling plan given hereunder in presence of firm’s representative.

II. The selected sample drum for CTL testing shall be identified by the seals

provided by Inspecting Officer / Inspecting Agency during pre-dispatch inspection at firm’s works and these sealing details shall be invariably mentioned in the selection Memo by the nominated officers of Nigam.

III. The tests in the Nigam Testing laboratory (CTL) shall be conducted in the

presence of representative of supplier for which a 7 days notice shall be issued through Fax / Speed Post stating Date & Time to the firm, so that supplier can depute their representative to witness the test . In case the supplier or his representative does not turn up the testing shall be proceeded & completed. The payment shall be released only after receipt of successful CTL test reports for the samples selected at purchaser’s stores for mandatory test checking the samples to be selected from material received at Nigam’s stores by officers to be nominated by Circle SE’s / SE (I&S) for testing at CTL.

10.1 SAMPLING

Selection of samples from the material received at stores shall be done as

soon as material received in stores in the presence of representative of supplier.

820

One number Drum out of each lot / sub-lot of 20 Nos. Drums or part thereof for the material received in Stores of Nigam. The selected sample drum / drums shall be transported to CTL by concerned ACOS / SS.

In case of selection of sample for type test the length of the sample shall be of 15

Mtrs. The selected and sealed sample for type test shall be identified by providing polycarbonate seals on both ends of conductor and after forming the coil of conductor two stickers seals provided around the coil.

10.2 TESTS

10.2.1. The following tests shall be carried out as per relevant Clause of latest IS-

398 (Part2)/1996 on each selected drum by drawing sample of 5 Mtrs. at CTL from random distance from any length of the selected drum of ACSR Conductor during rewinding:

a) Rewinding test (Measurement of Length and weight) & Checking

of Manufacturing defects. b) Measurement of lay ratio during rewinding of Conductor Drum. c) Dia. of Aluminum Strands and Steel Wires. d) Breaking load test. e) Resistance Test. f) Galvanization of steel wire (Uniformity) and Mass of Zinc

Coating. g) Verification of Water Proof marking on Drum as per

Specification. 10.2.2 The following tests shall be carried out as per relevant Clause of latest IS /

Specification on each selected drum by drawing sample of 5 Mtrs. at CTL from random distance from any length of the selected drum of Conductor during rewinding:

I. Rewinding test (Measurement of Length and weight) & Checking

of Manufacturing defects. II. Measurement of lay ratio during rewinding of Conductor Drum

III. Breaking Load test IV. Elongation Test V. Resistance test VI. Measurement of dia-meter of individual Aluminum. VII. Verification of Water Proof marking on Drum as per

Specification. NOTE: (a) In addition to above tests remaining acceptance tests as per relevant IS shall also be conducted at CTL provided the testing facility is available at CTL for these tests time to time. Only those tests shall be conducted for which testing facilities are available in NIGAM’s Lab.

821

(b) The Officer In charge of central Testing Lab (CTL) of Nigam shall send copies of test reports to the Purchasing Officer / Sr. AO (CPC), consignee and the supplier.

(c) The payment of every lot shall be released after receipt of

successful test report from Nigam’s Lab (CTL) on the samples selected from the material received in Nigam stores.

10.3 CRITERIA FOR ACCEPTANCE:

(a) Rewinding Test (Measurement of Length and weight):

The results of measurement of length test shall be made applicable to all drums contained in each lot/sub-lot by making deduction of less length of conductor in a sample drum. In case short length is observed more than one percent of the length contained in lot / sub-lot , then the lot / sub-lot shall liable to be rejected

The net calculated weight of conductor corresponding to minimum prescribed

diameter in IS of Aluminum Strand & Steel Strands shall be as under:

a) ACSR DOG 384.33 Kg./Km.

If weight of conductor corresponding to minimum prescribed diameter as per IS found less up to 2% in respect to measured length the lot shall be acceptable otherwise the entire lot for which sample drum represents shall be rejected and to be replaced by the supplier.

(b) If the sample(s) fail in any test other than length measurement, the entire material in the Lot shall be rejected and shall have to be replaced by the supplier.

c) If the contractor / supplier fails to lift the material declared rejected or any part

thereof from the consignee within a period of 15 days from the date of dispatch instruction from the purchaser, the purchaser shall be entitled to effect recovery along with other actions as per Clause No. 1.62 of Section-II (General Condition of Contract).

11.0 TEST CHARGES:



822

SCHEDULE-A

TYPE TEST CRITERIA:-

a. bidder shall furnish valid and authenticated type test certificate from a Govt. The approved / a Govt. recognized / NABL Accredited laboratory / ILAC i.e. International laboratory Accreditation Corporation (In case of foreign laboratory) of similar rating and design ( ACSR DOG CONDUCTOR) of tendered material / equipment.

b. The type test certificate by in house laboratory of biding firms even if it is a Govt. approved / Govt. Recognized / NABL Accredited laboratory / ILAC accredited , shall not be accepted, in case of their own bid. This will not apply if biding firm is Govt. company / public sector undertaking.

c. The bidder should furnish documentary evidence in support of laboratory whose type test have been furnished, that the said laboratory is a Government / Govt. approved / Govt. Recognized / NABL Accredited laboratory / ILAC accredited (In case of foreign laboratory).

d. The type test certificate shall be furnished either in original or copy duly attested by Notary.

823

TECHNICAL PARTICULARS OF ACSR DOG CONDUCTOR

---------------------------------------------------------------------------------------------------------------- S.N O. PARTICULARS ACSR CONDUCTOR

Dog ---------------------------------------------------------------------------------------------------------------

1. Manufacturer's name

Office address Work's address

Telephonic address Telephone Fax Telex Name of Contact Person

2. Code Name

3. Standard according to which the

conductor will be manufactured and tested.

4. Whether conductor offered bears

BIS standard mark. If yes, furnish copy of registration certificate of Bureau of Indian Standards.

5. Aluminum wires used in the

construction of aluminum conductors galvanized reinforced (ACSR) as per tables of IS;398(Part.2)/1996

a) Diameter in mm :

iv) Nominal v) Minimum vi) Maximum

b) Cross sectional area of nominal

Diameter wire (Sq. mm.) c) Mass (Kg./Km.)

824


Dog ---------------------------------------------------------------------------------------------------------------

d) Resistance at 20 Deg. C. Maximum (Ohms./Km.)

e) Breaking load (Min.)

i) Before Stranding (KN) ii) After Stranding (KN)

6. Steel wire used in construction

of aluminum conductors, galvanized steel reinforced (ACSR) as per tables of IS:398(Pt.2)/1996

a) Diameter :

i) Nominal (mm) ii) Minimum (mm)

iii) Maximum (mm)

b) Cross sectional area of nominal diameter wire (Sq.mm.)

c) Mass (Kg./Km.) d) Breaking load (Min.)

i) Before Stranding (KN)

ii) After Stranding (KN)

7. Aluminum conductor galvanized steel reinforced as per tables of IS:398 (Part.2)/1996 :

a) Nominal Al. area (Sq.mm.) b) Stranding and wire dia.

i) Aluminum (mm) ii) Steel (mm)

825

c) Sectional area of Al. sq.mm. d) Total sectional area sq.mm. e) Approx. overall diameter mm. f) Approx. Mass (Kg./Km.). g) Calculated resistance at

20 Deg. C. (Max.)(Ohms./Km.) h) Approximate calculated breaking load (KN)


Dog ---------------------------------------------------------------------------------------------------------------

8. a) Zinc coating of steel wire IS:4826/ 1979 with latest amendments.

i) No. of one minute dip. ii) No. of half minute dip.

b) Minimum weight of Zinc Coating

Gm./Sq. mtr.

9. Standard length in Meter

10. No. of the short lengths as per Clause No.10 of specification of Schedule-III

11. Total length in one drum

12. Net Mass of conductor in one drum (Kg.)

13. Tare Mass of the drum with lagging (Kg.)

14. Gross Weight of the drum including weight

of the conductor (Kg.)

15. Wooden Drums for ACSR `

826

Conductor :

i) Flange dia.

ii) Barrel dia.

iii)Traverse

16. Space between outer layer of Conductor and Inner surface of the external protective lagging of the drum after winding complete quantity of conductor in drum.

17. Other particulars if any.

SIGNATURE

Name & designation With seal of the bidder

827

TECHNICAL SPECIFICATION FOR SUPPLY OF 100 AMP. LT DISTRIBUTION KIOSK SUITABLE FOR UNDERGROUND CABLING.

1.0 SCOPE:- 1.1 This specification provides for the design, manufacture, inspection and testing before

supply for satisfactory operation. The LT Distribution Box suitable for outdoor use with floor mounting as per requirement indicated in the drawing.

1.2 It is not the intent to specify completely herein all the details of the design and construction of the equipment. However, the equipment shall conform in all respects to high standards of engineering, design and workmanship and shall be capable of performing in continuous commercial operation up to the bidder’s guarantee period, in a manner acceptable to the purchaser, who will interpret the meaning of drawing and specification and shall have the power to reject any work or material which in his judgment is not in accordance therewith. The offered equipment shall be complete with all components necessary for their effective and trouble free operation. Such components shall be deemed to be within the scope of bidder’s supply irrespective of whether those are specifically brought out in this specification and/or the commercial order or not.

2.0 APPLICABLE STANDARDS:-

The LT Distribution Box shall conform to the following Indian Standards which shall mean latest revisions, amendments/ charges adopted and published, unless otherwise / specified hereinafter. International and Internationally recognized standards to which these standards generally correspond are also listed below:

828

1 IS 13947/1993 (Part 2) For LT M.C.C.B.

2. IS 1852-1985 Specification for rolling & cutting tolerances. For hot rolled steel products.

3. IS 8623/1993 For enclosure box & for degree of protection for cubicles control gear.

4. IS:4237/1982,IS:8623/1993(amended upto date)

for general requirement of L.T. Switchgear

5. IS 6005 Latest code of practice for phosphate treatment of Iron & Steel.

3.1 GERERAL TECHNICAL REQUIREMENTS:-

(a) STANDARD:

The kiosk type weather proof outdoor type LT Distribution Box with hinged doors, on front & rear shall be fabricated out of 2.5mm M.S. CRCA sheet of fine quality with four legs made out of 50X50X6mm M.S. angles. Each door shall have concealed type two Nos. leaf hinges made of 2 mm MS sheet and 75 mm length. The box should have sloping canopy roof as shown in the drawing. Both front and rear doors should have heavy duty M.S. hinges and locking arrangements. 2.5mm thick bottom gland plate of M.S. with suitable individual opening of incoming outgoing cables (3.5 X 185 Sq.mm) and services cables of sizes (4Cx6/10/16/25 Sq.mm) as per requirement.

All the sheet steel work shall be phosphated in accordance with IS-6005 code for practice for phosphate iron and steel and capable of withstanding the mechanical, electrical, and thermal stresses as well as the same time ensuring the desired degree of safety. The same shall comply in all respect with the requirements as per relevant IS. In case of any discrepancy between write-up and drawing attached, the details given in drawings will prevail. The bill of material as indicated in the drawing shall be covered in the scope of supply.

829

(b) GENERAL TECHNICAL REQUIREMENT

Detailed as per drawing.

The box shall be kiosk type whether proof made out of 2.50mm thick MS sheet front and back both openable duly hinged doors with locking arrangement and all required hardware. The box should be dust and vermin proof followed by two coats of gray paints (IP 631) / powder coating. The box should be mounted on a separate stand of angle iron of angle size 50X50X6mm with a height of 1000 mm for grouted up to 500 mm below and above from the ground level.

(C) EARTHING TERMINALS

Two separate earthing terminals as shown in the drawing shall be provided.

(d) DANGER PLATE

Aluminum sheet 440V danger plate of size 120X150X1mm on front door should be provided.

(e) NAME PLATE

Manufacturer’s name plate of aluminum sheet of size 100X100X1mm quoting the IPDS/TN No. & Date is to be provided on the back door.

(f) SWITCH GEARS & WIRING

240 Volts, 160 Amp. at 0.4 pf Single pole MCCB 3 Nos. of Ics=18 KA with extended incoming and outgoing terminals of any makes having fixed type thermo-magnetic trip

830

release category P2. The overload release setting shall be 90 Amps. The name of manufacturer & Ics rating shall be embossed on MCCB. A Three Pole 200 Amp TPN MCCB of Ics=18 KA with extended incoming and outgoing terminals of any make be provided at back side of the box for protection of outgoing circuit. Complete wiring with 25 Sq.mm single core copper PVC (85 degree C grade) insulated cable duly crimped with oxygen free heavy duty copper terminals to connect each MCCB with EC grade aluminimum bus bars and bus bar to MCB’s. 240V, 10 kA breaking capacity AC MCB of rating 40 AMP SP 6 No’s. on each phase of make MDS load-contact legrand / SCHNEIDER ELECTIC MERLIN GERIN. / PROTEC / HAVELS/ L& T/ C&S / ABB/ HAGER / GERARD/ Indoasian/GUTS/MONTEL/HPL. Any other repute make of MCB having successful type tests reports shall also be accepted subject to prior approval of CE (MM),Jaipur Discom. All the 6 MCBs of one phase shall be shorted at the supply end using copper / brass finger type shorting link. The MCB,MCCB & TPN should be fully type tested. The successful bidder shall furnish detailed type test report of MCCB, MCB & TPN for approval.

Single compression copper/ brass cable gland for cable size 3.5 core 185 Sq.mm-3 Nos. & 4 core 10 Sq.mm-16 Nos.

(g) WORKMANSHIP

The fabrication of material shall be in such a way that it is a good finish of fabricated material. The welding wherever done should be smooth and uniform and shall be in accordance with the relevant standards. The material shall be fabricated accurately as per dimensions as indicated in drawings. All the steel section before any work is done on them, should be carefully leveled and straightened. No rough edges shall be permitted anywhere through out the work. Holes must be perfectly circular and dimensional tolerance as given below shall be permissible. All turns, sharp edges and rough surfaces left by drill or punch or any other process should be removed perfectly. The box should be such fabricated/welded that the rainwater does not enter into it.

(h) TOLERANCE

The sheet metal boxes shall be subjected to a maximum of ± 2% tolerance on the overall dimensions and rolling tolerance for sheet Distribution Box shall be as per relevant IS.

831

4.0 TEST 4.1 TESTING FACILITIES:-

The tenderer must indicate clearly about the various testing facilities for routine / acceptance tests as per relevant ISS in respect of distribution box as are available at the works/particulars of the place where such testing is proposed to be conducted during the course of inspection must be indicated.

4.2 ACCEPTANCE TESTS: a) Routine & Acceptance Test on complete box

The various tests (Acceptance/Routine) on the equipment/material shall be carried out as per provision of Section-III (technical specification). Out of offered lot, one sample for a lot of 50 or part thereof will be selected for carrying out following Acceptance Tests:-

1. Physical verification. 2. Dimensional checking. 3. Provision for earthing. 4. High voltage test.

The tests shall be conducted in presence of Nigam's representative. b) Routine & Acceptance Test on MCCB at original manufacturer’s works.

To ensure the quality of MCCB, routine & acceptance tests on MCCBs may be carried out at the works of original manufacturers. Before offering the complete box, the manufacturer should offer the MCCBs for inspection at the works of original manufacturer. The following tests shall be conducted only on samples MCCBs as routine/ acceptance for acceptance of the lot of MCCBs at the works of manufacturer during inspection.

1. Visual examination and overall dimensional checking.

832

2. High Voltage test at 2.5 KV for one second between:

a)-Main circuit & earth.

b)-Control circuit and earth.

c)-Shorted top and bottom terminals with MCCB in open conditions. 5. Insulation resistance test (IS: 8623) with 1000 V MEGGER between above points of S.N.2. 6. Milli-volt drop (IS:5147) 6. Temperature rise test (conducted one sample of each rating out of 1000 Nos. or part thereof)

in which contact resistance (mili volt) shall also be indicated. 7. Verification of time current characteristics (conducted one sample of each rating out of 1000

Nos. or part thereof).

The criteria for selection of No. of samples and for acceptance of lot shall be on 1% quantity or 10 Nos. samples whichever is more. Before dispatch, the MCCBs shall be inspected and tested by the authorized inspecting officer/Agency of the Nigam at the works of the manufacturer.

The successful testing of all samples in respect of tests mentioned above shall be the acceptability criteria of the lot/sub-lot.

4.3 ROUTINE TESTS:

The test specified at Clause No.4.2 shall constitute these tests and Shall be conducted on each piece and certificate for the same shall be submitted during bulk inspection in addition to acceptance test certificate mentioned above. Further, firm shall submit to the Inspecting Authority the copies of the test certificate of insulator / MCCB / MCB etc.

833

4.4 TYPE TESTS:

Tenderer shall submit type test certificate for the following as per relevant IS/IEC only from NABL accredited laboratory / Govt. lab. Along with the offer and offer received without these Certificates may be rejected without any further clarification/ confirmation.

1. MCCB/MCB/TPN : Type test certificates of manufacturers. 2. Complete Box : IP-33.

4.5 CTL TESTING:

The dimensional checking on One No. MCCB from each lot at Central Testing Lab of Nigam shall be carried out by braking the MCCB and matching the same with the internal drawing of type tested MCCB. The payment of particular lot shall be released only after successful testing at CTL.

5.0 GUARANTEED TECHNICAL AND OTHER PARTICULARS:

The guarantee technical and other particulars shall be given in the proforma as per schedule.


1.1 The bidder shall furnish valid and authenticated type test certificates from a Govt.



834

1.2 The bidder should furnish documentary evidence in support of the laboratory whose

type test have been furnished, that the said laboratory is a Govt. / a Govt. approved / a Govt. recognized / NABL accredited laboratory / ILAC accredited (in case of foreign laboratory).


835

GUARANTEED TECHNICAL PARTICULARS OF 100 AMP LT DISTRIBUTION BOX FOR DISTRIBUTION BOX.

Sr. No.

Description Guaranteed value As offered

1. Name and address of manufacture/firm.

2. Dimensions of box in MM.

500X550X700mm

3. Thickness of MS sheet. 2.5mm

4. Bus bar material & size EC grade 99.9 % pure Aluminimum (annealed) Size 40 x 8 mm (for all phases and neutral). The bus bar should not crack at the bends )

5. Length of bus 505 mm for phases (as per drawing) with 3 Nos. holes for holding lugs of 185 Sq. mm cable & 3 Nos hole of size 8 mm dia per phase and 300 mm for neutral.

6. Conical bus bar support DMC 40 x 40 mm with threaded brass inserts of 2.5 mm min. thickness at the thread.

7. Hardware Nickel plated

8. MCCB 3 Nos. single pole 160 Amps., Min. ICS=18 KA with over load release set 90 Amp.

9. TPN 1 No. three pole 200 Amps., TPN MCCB Min. ICS=18 KA.

10 MCB 18 Nos. Single pole 40 Amp., Min. 10 KA with “C” curve.

11. Earthing strip on DB Hot dip galvanized 25 x 3 mm as per drawing.

12 Dimensions of door locking / earthing bolt.

(a) Door Locking bolts.

836

(b) Earthin g bolts.

6 mm M10 2 Nos. with two nut & two washer.

13 Pad Lock On both side doors, MCB and MCCB box.

14. The complete box shall conform to

IP-33

15. Approximate weight of complete box in KG’s.

16. Dimensions for grouting.

500mm

Name of Firm

Signature of Bidder

Designation & Seal

Date

837

TECHNICAL SPECIFICATION FOR SUPPLY OF 11 KV 4 WAY FEEDER PILLAR.

1. SCOPE:

This specification provides for the design, manufacture, stage inspection and testing before supply for satisfactory operation. The 11KV Feeder Pillar is suitable for out door use with floor mounting as per required indicated in the drawing.

It is not the intent to specify completely herein all the details of the design and construction of the equipment. However, the equipment shall conform in all respects to high standards of engineering, design and workmanship and shall be capable of performing in continuous commercial operation up to the bidder’s guarantee period, in a manner acceptable to the purchaser, who will interpret the meaning of drawings and specification and shall have the power to reject any work or material which in his judgment is not in accordance therewith. The offered equipment shall be complete with all components necessary for their effective and trouble free operation . Such components shall be deemed to be within the scope of bidder’s supply irrespective of whether those are specifically brought out in this specification and / or the commercial order or not.

2.1. APPLICABLE STANDARDS:

The Feeder Pillar shall conform to the following Indian Standards which shall mean latest revisions, amendments / charges adopted and published, unless otherwise / specified hereinafter. International and Internationally recognized standards to which these standards generally correspond are also listed below:

(1) IS 14772/IEC 60670 (1989) :- General requirement for enclosure for

accessories for household & similar fixed electrical installations.

(2) IS 1852-1985 :- Specification for rolling & cutting tolerances

For hot rolled steel products.

838

(3) IS 2147 :- Degree of protection for cubicles control gear.

(4)

IS 6005

:-

Latest code of practice for phosphate

treatment of Iron & Steel.

(5)

GSE 94

:-

Specification for powder coating tests.

3.0 GENERAL TECHNICAL REQUIREMENTS:

The weather proof out door Feeder Pillar with doors shall be fabricated out of 3.15mm M.S. sheet of fine quality. The box should have slopping canopy roof as shown in the drawing. Both front and rear doors should have 3 heavy duty M.S. hinges with Brass pin inserted inside and locking arrangements. 3.15mm thick bottom Gland plate of M.S. with suitable individual opening of (04 Nos.) with Fiber glass coating shall be provided. The bottom sheet should have suitable holes of the required size suitable for 3Cx300/185 SQMM 11KV XLPE Cable.

All the sheet steel work shall be phosphated in accordance with IS – 6005 code for practice for phosphate iron and steel and capable of withstanding the mechanical, electrical and thermal stresses as well as the same time ensuring the desired degree of safety. The same shall comply in all respect with the requirements as per relevant IS. In case of any discrepancy between write-up and drawings attached, the details given in drawings will prevail. The bill of material as indicated in the drawings shall be covered in the scope of supply.

The HT Feeder Pillar box should be fabricated out of 3.15mm MS Sheet having IP 43 degree of protection with bottom frame made out of 50x50x5mm MS Angle. The pillar should be adequately ventilated with louvers that will be with 1mm perforated sheets on sides. Slopping canopy roof with groove will be as shown in the drawing. Door should be provided on both side front and rear. One handle welded on each door made from 10mm dia MS Rod bend in ‘C’ shape. Additional inner door should be provided at front as well as rear side made from 10SWG GI wire mesh with 5x5mm square mesh. A removable 3mm thick fiber sheet should be provided on right and left sides from inside.

839

Bottom covers made from 3.15mm MS sheet should be provided on all sides below box but above the foundation frame stand. The front and rear cover should have ventilation louvers with 1mm thick perforated sheet from inside. The bottom foundation frame stand should be made from 65x65x6mm MS Angle with four legs of 200mm height provided with 150x150x6mm flats with foundation holes welded with this frame. The pillar box and foundation frame stand should be bolted type from inside in such a way that bolts are not visible without removing bottom covers.

Arrangement for holding each XLPE cables with proper clamps at two ends, one inside box and another inside bottom frame with the help of GI clamp along with nut, bolts, washers etc. as shown in the drawing, shall be provided.

(b) SEALING ARRANGEMENT

The right door should have locking arrangement on top and bottom side and arrangement with the left door in such a way that left door cannot be opened without opening the right door. Padlocking arrangement should be provided at the center of door, one with small MS Angle piece made from 10SWG sheet and another with MS flag 40x5 mm (welded with door) through out width of pillar with hinge at one end riveted with sides and padlocking arrangement at the other end at the center of door as shown in the drawing.

(C) INCOMING AND OUTGOING CABLE ARRANGEMENTS

(i) Bushing and its fixing arrangement:

Epoxy resin/porcelain solid bushing type (support insulator) conforming to respective IS having suitable creepage distance for 11KV grade which should be able to clear all specified type tests. The technical particulars like dimensions, insulation level, impulse level etc. be submitted along with offer. The solid bushing shall be provided in the pillar box as shown in the drawing. The bus shall be supported on bushing/insulator. The bushing shall have adequate cantilever strength to withstand the maximum short circuit forces under fault conditions as specified. The bushing shall not deteriorate under normal operating temperature or due to temperature rise under fault conditions. Further, tenderer shall

840

submit type test certificates of the offered feeder pillar from NABL accredited laboratory along with offer, otherwise the offer may be rejected.

(ii) s Bar:

The Bus Bar should be made out of high conductivity electrolytic tinnd copper. The Bus Bar should be link type/detachable type as shown in the drawing. There should be totol 9 number of bus bar links of size 50x6mm. The Bus bar should be taped with heat shrinkable tape or insulated powder coating suitable for 11KV insulation red, yellow and blue color codes.

(d ) EARTHING OF BOX

Two separate earthing terminal with lugs as shown in the drawing shall be provided.

(e) DANGER PLATE

Enameled danger plate of size200x150mm on top, left hand side of the front door should be provided.

(f) NAME PLATE

Manufacturer’s name plate of Aluminum sheet of size 100x100x1mm quoting the purchase order No & Date is to be provided at the top right hand side of the door.

(g)WORKMANSHIP

The fabrication of material shall be done in such a way that there is a good finish of fabricated material. The welding wherever done should be smooth and uniform and shall

841

be in accordance with the relevant standards. The material shall be fabricated accurately as per dimensions as indicated in drawings. All the steel sections before any work is done on them, should be carefully leveled and straightened. No rough edges shall be permitted anywhere through out the work. Holes must be perfectly circular and dimensional tolerance as given below shall be permissible. All turns, sharp edges and rough surfaces left by drill or punch or any other process should be removed perfectly. The box should be such fabricated/welded that the rainwater does not enter into it.

(h) TOLERANCE:

The sheet metal boxes shall be subjected to a maximum of ± 2% tolerance on the overall dimensions and rolling tolerance for sheet Pillar Box shall be as per relevant IS.

(i) PROTECTION AGAINST CORROSION AND PAINTING PROCEDURE:

After fabrication work the entire box including legs should be given anti corrosive treatment before carrying out electro static powder coating with oven backing. All boxes shall be adequately protected against rust, dust and corrosion both from inside and outside as under:

i) All sheet steel work shall be phosphate in accordance with IS- 6008 code of practice for phosphate iron and steel.

ii) Oil, greese, durt etc. shall be thoroughly removed by emulsion cleaning. iii) Rust and scale be removed by pickling with dilute acid followed by washing with

running water rinsing with slightly alkaline hot water and drying. iv) After phosphate thorough rinsing shall be carried out with clean water followed by final

rinsing with dilute dichromate solution and oven drying. v) The phosphate coating shall be sealed with application of Electrostatic processed

Coating oven baked type Epoxy based Powder of the color shade as specified above 4.0 TESTS:

4.1 TESTING FACILITIES:

842

The tenderer must indicate clearly about the various testing facilities for routine/acceptance tests as per relevant ISS in respect of distribution box as are available at the works/particulars of the place where such testing is proposed to be conducted during the course of inspection must be indicated.

4.2 TEST VALUES:

For all acceptance tests, the acceptance values shall be the values guaranteed by the bidder in the guaranteed technical particulars or the acceptance value specified in this specification or the relevant standards whichever is more stringent.

4.3 ACCEPTANCE TESTS

Criteria for acceptance: selected samples per lot should successfully pass following tests for proving their conformity with the above requirements. If any of the sample fails in any of the tests, the testing authority, at its discretion, may select fresh sample not exceeding twice the original number and subject to all tests or to the tests in which the failure occurred.

The following tests shall constitute the acceptance test:

1. Physical verification. 2. Dimensional checking. 3. Provision for earthing. 4. High voltage test. 5. Scratch test for Powder Coating. 6. Thickness of Powder Coating.

4.4 ROUTINE TESTS:

The test specified at Sl.No.1 to 4 in the Clause No.4.3 shall constitute these tests and shall be conducted on each piece and certificate for the same shall be submitted during bulk inspection in addition to acceptance test certificate mentioned above. Further, tenderer

843

shall submit to the Inspecting Authority the copies of the test certificate of Insulator /Bushing as well as chemical analysis report for electrolytic copper strips at the time of inspection for his approval.

4.5 TYPE TESTS

Tenderer shall submit type test certificate for the followings as per relevant IS/IEC only from NABL accredited laboratory along with the offer and offer received without these certificates may be rejected without any further clarification/confirmation.

1. Insulator/Bushing : Type test certificates of manufacturers 2. Complete box : Following test shall be applicable on complete unit:

a. Degree of protection : IP –33 as per IS 13947 b. Adhesive tests for Powder Coating as per GSE 94 c. Damp test for Powder Coating as per GSE 94 d. Power frequency withstand test at 28 KV e. Impulse wave withstand test at 75KV

4.6 PRINCIPAL PARAMETERS OF HT FEEDER PILLARS:

a) General Technical Requirement:

Dimension of HT Feeder Pillar shall be as under:-

Height (including foundation angle) 1650mm

Width 1000mm

Depth (without door) 1000mm

The box shall be suitable for housing all of the following items:-

i) Insulator bushing : 12 Nos.

844

ii) 50x6sq.mm.copper strip : 9 Nos.

b) Cable entry/Exit:

Four holes at the bottom shall be provided for incoming and outgoing 11KV cables, connections to be made. The clamping arrangement shown in the drawing shall be provided for holding 11KV cable.

5.0 GUARANTEED TECHNICAL AND OTHER PARTICULARS:

The guarantee technical and other particulars shall be given in the proforma as per schedule.


1.1 The bidder shall furnish valid and authenticated type test certificates from a Govt.



1.2 The bidder should furnish documentary evidence in support of the laboratory whose

type test have been furnished, that the said laboratory is a Govt. / a Govt. approved / a Govt. recognized / NABL accredited laboratory / ILAC accredited (in case of foreign laboratory).


845

Schedule – V(A)

GUARANTEED TECHNICAL AND OTHER PARTICULARS FOR 11KV FEEDER PILLAR BOX.

Sl. No.

Description Guaranteed value As offered

1 Name and works address of manufacturer/ firm

2 Dimensions of box in MM 1000X1000X1500 mm

3 Thickness of MS sheet 3.15mm

4 Dimension of door locking/earthing bolt

(a) Door padlocking bolts (b) Earthing bolts

5 Approximate weight of complete box in KGs.

6 Details of powder coating a) shade no. of color/paint

b) sand/shot blasting

7 Tolerance in fabrication

8 Dimensions of bottom angle framework

a) Length b) Width c) Thickness

9 Make and rating of Epoxy Bushing/ Insulator

10 Creepage distance of insulator

Name of Firm

Signature of Bidder

Designation & Seal

Date

846

TECHNICAL SPECIFICATION FOR SPRING LOADED CONSTANT PRESSURE MULTI CONNECTION BUS BAR DISTRIBUTION BOX FOR SINGLE PHASE SUPPLY SYSTEM

1.0 SCOPE

This specification covers design, manufacture, assembly testing at manufacturer's works, packing and delivery at site(s)/store(s) of Nigam with accessories of spring loaded constant pressure multi connection bus bar distribution box for single phase supply system made of insulating material in Jaipur Discom.

2.0 STANDARDS :


Sl. No.

Standard No.

1. IS:14772

2. IS:8623

3. IS:13411

4. IS:4249

5. IS:11731

6. IS:11000


Equipment to be supplied against this specification shall be suitable for satisfactory continuous operation under the following tropical conditions :

performance and testing of spring loaded bus bar shall conform to the latestrevisions and amendments of the following standards .

847

i) ii)

Location

Max. ambient air

Anywhere in Rajasthan

50 iii)

temp. in shade (deg.C)Min. ambient air temp. (Deg.C)

(-)5

iv) Average daily ambient air temperature(Deg.C.)

45

v) Max. yearly weighted ambient temp.(Deg.C.)

35

vi) Max.Relative humidity (%) 95

vii) Average annual rainfall (mm)

100 to 1000mm (depending upon area)

viii) No. of rainy days P.A. 70

ix) Max. wind pressure (Kg/sq.m.) 195

x) Max. altitude above mean sea level (metres)

815

xi) Isoceranic level (days/year).


xii) Seismic level (horizontal acceleration).

0.08g

Note : Moderately hot and humid tropical climate conductive to rust and fungus growth. The climatic conditions are also prone to wide variations in ambient conditions. Smoke is also present in the atmosphere. Heavy/lightning also occurs during June to October.

4.0 TECHANICAL PARTICULARS, MATERIAL & CONSTRUCTIONAL DETAILS: 4.1 FOR SPRING LOADED CONSTANT PRESSURE MULTI CONNECTION BUS BAR DISTRIBUTION BOX FOR SINGLE PHASE SUPPLY SYSTEM ( One incoming + Five Outgoing Circuits i.e. SP-6 Type)

4.1.1 MATERIAL OF BOX : a. The box (enclosure) shall be made of Glass Filled U.V. Stablised Fire Retardant

Nylon 6.6 or UV resistant Fire Retardant polycarbonate with min 2.5 mm thickness, capable of withstanding boiling water for 10 minutes without deformation of box

848

material. The heat deflection temperature of the box material should be 125 C @ 0.45mpa. The flammability rating of the material as per UL 94 should be V0.

b. Moulded casing of Bus Bar shall be made of Nylon glass filled capable of

Fire retardency test at 9500C as per Specification No. IEC Publication 695 – 2 –1.

4.1.2 DIMENSION OF THE BOX:

The minimum internal dimensions of the box (enclosure) should not be less than

the following dimensions :

a) In case of Bus Bar Distribution Box

for Single Phase System : 250x250x160mm

The other Dimensions & General details shall be as mentioned in the Specification/ GTP/ Drawing.

4.1.3 Busbars: The Bus bars should be made of EC grade copper. The minimum current rating of busbars should be 200 Amp and the total cross section area should be such that the current density should not exceed 2.5 Amp/ Sq.mm. The minimum length of copper bus bars should not be less than 125 mm.

SP-6 Type ( One incoming and five outgoing circuits) = 125mm The Busbars meeting the requirement of aforesaid current rating and maximum current density be provided in two identical pairs for Phase as well as for neutral.

Two sets of Nylon supports are to be provided at the ends of Bus Bar casings to enable it to be fixed at Base at an easy to wire angle. The four ends of the Nylon supports shall be suitably affixed with the base of box by providing Nuts, Bolts & Washers.

4.1.4 ring loading system:

The connections should be spring loaded so that no fasteners are required to add a new connection from the distribution system. Also, each connected cable shall have a pressure applied to it at the point of connection to provide connection integrity and eliminate loose connections.

The pressure plates which keep pressing the cable conductor & springs with

sufficient strength of thickness 2 mm and diameter of spring wire should not be less than 2.0 mm. Both are to be made of stainless steel only.

849

The springs are required to be retained in the housing by means of a stainless steel rod at the bottom end of the housing, so as to exert pressure on the pressure plate, when cable is inserted in the Bus Bar. . The minimum spring size should be 35mm from end to end, with an outer diameter of 14.25 mm and wire dia of 2mm.

The pressure plates and bus bar system should be suitable for incoming 50 sq. mm Aluminum / Copper cable and 35 sq mm Aluminum / Copper cable for outgoing circuits.

4.1.5 ARRANGEMENT OF BUSBARS:

The Busbar housings shall be arranged and mounted at a suitable stepped

angle so that making new connections is easy and without much bending of the cables. 4.1.6 SEALING OF BOX : The enclosure cover shall have a U clamp sealing system with 2 Nos. zinc passivated U clamps with holes.

4.1.7 I.P.Level : For protection against ingrace of moisture, Water Particles and Dust etc., the box should meet

with I.P. Level - I.P-55.

a. Neoprene rubber gasket be provided all around the cover . b. The box shall have built in type hinges, no screws/rivets be visible

from outside. 4.1.8 Gland Plate :

At bottom side of the enclosure, a M.S. Hot Dip Galvanised 1.2 mm sheet Gland Plate with 6 Nos. of holes is to be provided for one incoming and five outgoing cables as per drawings.

4.1.9 Earthing Plate :

The one No. 2 mm thick Hot Dip Galvanised earthing Plate of size indicated in the drawing shall be provided at bottom side of the distribution box to accommodate earthing wire or armour running with cables.

4.1.10 OTHER COMPONENTS & FEATURES:

850

1. There shall be a provision of one incoming circuit of Single Phase & Neutral and 5 Nos. Outgoing connections of Single Phase and Neutral in the bus bars.

2. One Set (2 nos.) of Busbar moulded casing each containing one set (2 nos.) of busbars and the spring loading system along with pressure plates should be provided

3. The box shall have built in type hinges, no screws/rivets visible from outside.

4. Neoprene rubber gasket to be provided all around the cover . 4.1.11 Arrangement for mounting of Box on Pole :

The box shall be provided with 2 Nos. of M.S. Hot Dip Galavanised mounting channels of thickness 1.6 mm and 2 Nos. M.S.Round U Clamps Hot Dip Galvanised with Nuts & washers for fixing the Box on the holes. The size of mounting channel and U clamp shall be as specified in the Specification / GTP / Drawing.

5.0 TECHNICAL PARAMETERS FOR SPRING LOADED CONSTANT PRESSURE MULTI CONNECTION BUS BAR DISTRIBUTION BOX FOR SINGLE PHASE SUPPLY SYSTEM.

S/No. Particulars Description

1 Material of Box / Enclosure

Glass Filled U.V. Stablised FireRetardant Nylon 6.6 or UV Resistant Fire Retardant polycarbonate

2 Thickness of box Min 2.5 mm

3 Dimension of box / enclosure

250 x 250 x 160mm

4 Material of insulation for mounting Bus bar (Bus Bar Supports)

Nylon Glass Filled FR

5 No. of circuits both incoming & outgoing in the Bus bar

One incoming + 5 Outgoing Circuits

6 Material of Insulation for Bus bars moulded casing

Nylon Glass filled capable to withstandFire Retardant Test at 9500C as perIEC Publication 695–2–1.

851


7 Material of Bus Bar EC Grade Copper

8 Cross Section area of Bus Bar

To meet current rating of 200 Amp and current density less than 2.5 Amp/ Sq mm

9 No. of Busbar completed with fitting

2 sets (4 nos.), One set for Phase & One set for Neutral.

10 Length of Copper Bus Bar with Tin/Silver Plating

125mm

11 Pressure Plate Thickness 2.0 mm stainless steel

12 Insulation level 2.5KV A.C. R.M.S. as per IS: 8623 (Part I) 1993

13 Earthing Plate 1 No. 2 mm M.S. Hot Dip Galvanised

14 Earthing bolts, Washers and Nuts.

06 Nos. M8

15 Earthing Logo Earthing symbol

16 Distance between phase and neutral

Center to Center distance 35 – 40mm

17 Hinges 2 Nos. built in type hinges, No screws/rivets permissible.

18 IP Level IP 55

19 Sealing U Clamp 2 Nos. 1.2 mm Zinc passivated.

20 Holes for cable As per respective drawings

21 Mounting channels MS

2 Nos. (1.6 mm Thick M S Hot Dip Galvanised )

22 Pole Clamp for fixing the box on the pole

2 Nos. M.S. Round U Type Clamp Hot Dip Galvanised with Nuts & washers as per dimension indicated in the drawing.

23 Gland Plate 1 No. 1.2 mm Hot Dip Galvanised

24 Suitable for incoming cable size

50 Sq mm Aluminum Cable

25 Colour Grey

26 Marking a) Name or trade mark of manufacturer. b) JPD c) TN-4216

Note: The Nuts & Washers may be Electroplated. 6.1 MARKING :

852

The following shall be embossed on the cover of box in big font :

a) Name or trade mark of the manufacturer. b) JPD c) TN No./IPDS

7.0 DRAWINGS : i) The tenderers shall submit with his tender the bill of material and fully dimensional drawing of the offered material clearly showing the full details of material components to be supplied by them to enable the purchaser to examine the offer. The following drawings are appended with this specification:

a) General Arrangement b) U-Clamp c) Bus Bar enclosure earth plate d) Channel for mounting the box on the Pole.

ii) The successful bidder will submit the full dimensional drawing on A-3 size paper in triplicate for all the components for approval of purchaser as per specification before commencement of supply. If the successful bidder manufacture the equipment without obtaining approval of drawing, the purchaser will not be responsible if any part is not as per required dimensions. Approval of drawings/ work by Purchaser shall not relieve the Supplier of his responsibility and liability for ensuring correctness and correct interpretation of the latest revision of applicable standards, rules and codes of practices.

8.1 TESTS :

8.2 TYPE TESTS :

a) The tenderer should furnish valid type test certificates from Central Power Research Institute (CPRI) or NABL accredited independent test laboratory on similar rating and design of tendered material/equipment i.e. separate type test report for single phase and three phase Spring Loaded Constant Pressure Multi-connection Bus Bar Distribution Box. Tests carried out by tenderer in his own R&D units even if recognized by NABL shall not be accepted except incase of Govt. undertakings.

853

b) Bidder should also furnish documentary evidence in support of laboratory (Other than CPRI ) whose Type Test reports have been furnished that the said laboratory is NABL accredited laboratory.

c) Such type test certificates should not be older than three years as on the date of bid opening.

8.3 The type tests to be conducted on Spring Loaded Constant Pressure Multi- connection Distribution Box as per relevant IS. The following tests shall constitute the type tests:

S.NO NAME OF TEST STANDARD CLAUSE NO. A FOR ENCLOSURE (BOX)

1 Visual examination As Per GTP/ approved drawing

2 Verification of dimensions & Marking As Per Spec/GTP/approved drawing

3 Protection against electric Shock IS:14772 9

4 Resistance to ingress of solid object & to harmful ingress of water ( IP-55 )

IS:14772 12

4 Test of Mechanical Strength / Impact Resistance Test

IS:14772 13

5 Resistance to heat IS:14772 14 6 Resistance to Rusting IS:14772 16 7 Glow Wire Test at 950 degree

Centigrade IS:14772/ IEC 695-2-1

8 Verification of Dielectric Properties at 5 KV

IS:8623 8.2.2.2

Heat Deflection Test at 125 degree Centigrade at 0.45 Mpa

Test for Self Extinguishing Properties

IS:4249 3.5.1

9 Flammability Test IS:11731 II

10 U V Resistance Test Din 53387

11 Withstand Voltage Test

B FOR BUS BAR

854

S.NO NAME OF TEST STANDARD CLAUSE NO. 12 Temperature Rise Test IS:8623-I 8.2.1 13 Verification of Dielectric

Properties of moulded casing of bus bar at 5KV

IS:8623-I 8.2.2

14 Glow Wire Test at 950 degree Centigrade of moulded casing bus bar

IS:11000- 1/IEC 695-2-1

i) IP-55 Test Report for the types of enclosures specified to be furnished with the tender.

ii) Type test reports of Heat run test on at least one set of Bus Bar either single phase or three phase bus bar with 200A heat run test has to be furnished with the tender.

8.4 The above tests should be carried out on the samples in the order mentioned in relevant IS.

8.5 TESTS BEFORE DISPATCH :

The material shall be subjected at manufacturer's works before dispatch to the

routine & acceptance tests given here-under as per relevant IS. 8.6 ACCEPTANCE TESTS :

These tests shall be carried out on the samples taken from the lot for the purpose of

the acceptance of lot which are to be conducted as per relevant IS:


1 Visual examination As Per GTP/ approved drawing 2 Verification of dimensions As Per GTP/ approved drawing

3 Protection against electric Shock

IS:14772 9


IS:14772 13

5 Glow Wire Test at 950 degree Centigrade

IS:14772/ IEC 695-2-1


IS:8623 8.2.2.2

7 Test for Self Extinguishing Properties

IS:4249 3.5.1


855

S.NO NAME OF TEST STANDARD CLAUSE NO. B FOR BUSBAR

9 Temperature Rise Test IS:8623-I 8.2.1 10 Verification of Dielectric


IS:8623-I 8.2.2


IS:11000- 1/IEC 695-2-1

8.7 ROUTINE TESTS :

These tests are to carried out to check various requirements of Spring Loaded Constant Pressure Multi-connection Distribution system which are likely to vary during production. The following tests shall be conducted / carried out on Spring Loaded Constant Pressure Multi-connection Distribution system by the bidder at his works as per relevant IS and he should furnish certificate / record thereof during pre- dispatch inspection:-

i) Verification of dimensions & Marking ii) Protection against electric Shock iii) Test for self extinguishing properties

9.0 TESTS AT SITE :

The purchaser reserves the right to conduct all tests on each type of Spring

Loaded Constant Pressure Multi-connection Distribution system after arrival at site and bidder shall guarantee test certificates figures under actual service conditions.


The bidder should possess adequate testing facilities for carrying out routine &

acceptance test of item as per relevant standard at their works. The bidder shall furnish documentary evidence in support of conducting routine & acceptance test. The per day capacity of testing facilities at the works of the bidder shall be verified by the representative of the purchaser.

11.1 INSPECTION :

11.2 All the routine /acceptance tests as mentioned above for pre-despatch inspection shall be conducted at the place of manufacturer unless otherwise especially agreed upon by the bidder and purchaser at the time of purchase. The bidder shall afford the inspection officer(s) representing the purchaser all reasonable facilities without

856

charges, to satisfy him that the material is being furnished in accordance with this specification. The purchaser has the right to have the tests carried out at his own cost by an independent agency whenever there is a dispute regarding the quality of supply.

11.3 The inspection may also be carried out by the purchaser at any stage of manufacture / before dispatch as per relevant standard.

11.4 Inspection and acceptance of any material under the specification by the purchaser, shall not relieve the bidder of his obligation of furnishing material in accordance with the specification and shall not prevent subsequent rejection if the material is found to be defective. The bidder shall keep the purchaser informed in advance, about manufacturing programme so that arrangements can be made for inspection.

11.5 The purchaser reserves the right to insist for witnessing the acceptance / routine testings of the bought out items.

11.6 The bidder shall give 15 days advance intimation to enable the purchaser to depute his representative for witnessing the acceptance and routine tests. The inspection charges would be to the purchaser's account.



given in Schedule-V(A). 13.1 TEST CHECKING OF MATERIAL AT STORES

The material received in the stores of the NIGAM shall be subjected to the test

checking at stores before final acceptance of the material, the procedure for the same shall be as under :

13.2 SAMPLING

One sample of each type out of each sub-lot / lot of 500 Nos. or part thereof

from each inspected lot received in stores shall be selected for test checking of material and shall be got tested.

The sample selection shall be done as soon as the material is received in stores, without calling the representative of supplier. However, testing at CTL shall be done in the presence of representative of supplier after identification/ confirmation by the supplier’s representative that sample(s) so selected belong to them.

13.3 TESTS

857


a) Visual Examination, verification of dimensions and marking as per GTP/ approved drawing.

b) Any other acceptance test for which facility are available in CTL.

Checking of material of Box , Busbar, Busbar Casing and Busbar Support.

13.4 Test of the material shall be got done at the test laboratory of the NIGAM .For witnessing of the testing, 7 days notice shall be given to the supplier stating date, time & place . In case the supplier do not attend for witnessing the testing, the testing shall be proceeded and completed and action taken as per the contract.

13.5 Officer Incharge of CTL i.e. XEN(CTL) shall send copies of test reports to the purchaser, consignees and the supplier.


In case of failure of sample, the material contained in the lot / sub-lot to which

the sample belongs, shall be rejected. The rejected material shall have to be replaced by the supplier free of cost.

13.7 TEST CHARGES :

All test charges incurred towards test checking of the material received in our

stores shall be borne by the NIGAM. 13.8 PAYMENT: Payment shall be made only after receipt of successful tests report from the CTL on the

samples selected from the material received at the stores.

858

SCHEDULE-V (A)

GUARANTEED TECHNICAL PARTICULARS (G.T.P.) FOR SPRING LOADED CONSTANT PRESSURE

MULTI CONNECTION BUS BAR DISTRIBUTION BOX FOR SINGLE PHASE SUPPLY SYSTEM.


1 Manufacturers Name and address

2 Place of Manufacture

3 Material of Box / Enclosure

Glass Filled U.V. Stablised FireRetardant Nylon 6.6 or UV Resistant Fire Retardant polycarbonate

4 Thickness of box Min 2.5 mm

5 Dimension of box / enclosure

250 x 250 x 160mm

6 Material of insulation for mounting Bus bar (Bus Bar Supports)


7 No. of circuits both incoming & outgoing in the Bus bar

One incoming + 5 Outgoing Circuits

8 Material of Insulation for Bus bars moulded casing

Nylon Glass filled capable to withstandFire Retardant Test at 9500C as perIEC Publication 695–2–1.





2 sets (4 nos.), One set for Phase & One set for Neutral.


125mm

13 Pressure Plate Thickness 2.0 mm stainless steel


15 Earthing Plate 1 No. 2 mm MS Hot Dip Galvanised

859


16 Earthing bolts, Washers and Nuts.

06 Nos. M8


18 Distance between phase and neutral

Center to Center distance 35 – 40mm

19 Hinges 2 Nos. built in type hinges, No screws/rivets permissible.

20 IP Level IP 55

21 Sealing U Clamp 2 Nos. 1.2 mm zinc passivated

22 Holes for cable As per respective drawings


2 Nos. (1.6 mm Thick M S Hot Dip Galvanised )


2 Nos. M.S. Round U Type Clamp Zinc passivated with Nuts & washers as per dimension indicated in the drawing

25 Gland Plate 1 No. 1.2 mm Hot dip Gavanised


50 Sq mm Aluminum Cable

27 Color grey

28 Marking a) Name or trade mark of manufacturer. b) JPD c) TN No./IPDS

Note: The Nuts & Washers may be Electroplated.

Name of Firm

Signature of Bidder

Designation & Seal

Date

860

TECHNICAL SPECIFICATION FOR SPRING LOADED CONSTANT PRESSURE MULTI CONNECTION BUS BAR DISTRIBUTION BOX FOR THREE PHASE SUPPLY SYSTEM

1.0 SCOPE

This specification covers design, manufacture, assembly testing at manufacturer's works, packing and delivery at site(s)/store(s) of Nigam with accessories of spring loaded constant pressure multi connection bus bar distribution box for three phase supply system made of insulating material in Jaipur Discom.

2.0 STANDARDS :


Sl. No.

Standard No.

1. IS:14772

2. IS:8623

3. IS:13411

4. IS:4249

5. IS:11731

6. IS:11000


Equipment to be supplied against this specification shall be suitable for satisfactory continuous operation under the following tropical conditions :

i) Location Anywhere in Rajasthan

ii) Max. ambient air 50

performance and testing of spring loaded bus bar shall conform to the latestrevisions and amendments of the following standards .

861

iii)

temp. in shade (deg.C) Min. ambient air temp. (Deg.C)

(-)5

iv) Average daily ambient air temperature(Deg.C.)

45

v) Max. yearly weighted ambient temp.(Deg.C.)

35

vi) Max.Relative humidity (%) 95

vii) Average annual rainfall (mm)

100 to 1000mm (depending upon area)

viii) No. of rainy days P.A. 70

ix) Max. wind pressure (Kg/sq.m.) 195

x) Max. altitude above mean sea level (metres)

815

xi) Isoceranic level (days/year).


xii) Seismic level (horizontal acceleration).

0.08g

Note : Moderately hot and humid tropical climate conductive to rust and fungus growth. The climatic conditions are also prone to wide variations in ambient conditions. Smoke is also present in the atmosphere. Heavy/lightning also occurs during June to October.

4.0 TECHNICAL PARTICULARS, MATERIAL & CONSTRUCTIONAL DETAIL: 4.1 FOR SPRING LOADED CONSTANT PRESSURE MULTI CONNECTION BUS BAR

DISTRIBUTION BOX FOR THREE PHASE SUPPLY SYSTEM (One incoming + five Outgoing Circuits in each of three Phase and 1+9 Outgoing Circuits in Neutral)

4.1.1 MATERIAL OF BOX :

a) The box (enclosure) shall be made of Glass Filled U.V. Stablised Fire

Retardant Nylon 6.6 or UV resistant Fire Retardant polycarbonate with min 3 mm thickness, capable of withstanding boiling water for 10 minutes without deformation of box material. The heat deflection temperature of the box

862

material should be 125ºC @ 0.45 mpa. The flammability rating of the material as per UL 94 should be Vo.

b). Moulded casing of Bus Bar shall be made of Nylon glass filled capable of

Fire retardency test at 950ºC as per Specification No. IEC Publication 695 – 2 –1.

4.1.2 DIMENSION OF THE BOX:

The minimum internal dimensions of the box (enclosure) should not be less than the

following dimensions :

In case of Bus Bar Distribution Box

for Three Phase System : 400x300x190mm.

The other Dimensions & General details shall be as mentioned in the Specification/ GTP/ Drawing.

4.1.3 bars: The Bus bars should be made of EC grade copper. The minimum

current rating of busbars should be 200 Amp and the total cross section area should be such that the current density should no exceed 2.5 Amp/ Sq.mm. The minimum length of copper bus bars should not be less than as follows-

Phase Busbar for 1 incoming +5 outgoing circuits = 125 mm

Neutral Busbar for 1 incoming +9 outgoing circuits = 210 mm The Busbars meeting the requirement of aforesaid current rating and maximum current density be provided in two identical pairs for each Phase as well as for neutral.

Two sets of Nylon supports are to be provided at the ends of Bus Bar casings to enable it to be fixed at Base at an easy to wire angle. The four ends of the Nylon supports shall be suitably affixed with the base of box by providing Nuts, Bolts & Washers.

Semi Circular grooves should be provided on Bus Bars in Distribution Boxes, so as to have

sufficient contact area between bus bars and conductor of cable.

4.1.4 ring loading system:

863

The connections should be spring loaded so that no fasteners are required to add a new connection from the distribution system. Also, each connected cable shall have a pressure applied to it at the point of connection to provide connection integrity and eliminate loose connections.

The pressure plates which keep pressing the cable conductor & springs with

sufficient strength of thickness 2 mm and diameter of spring wire should not be less than 2.0 mm. Both are to be made of stainless steel only.

The springs are required to be retained in the housing by means of a stainless

steel rod at the bottom end of the housing, so as to exert pressure on the pressure plate, when cable is inserted in the Bus Bar. . The minimum spring size should be 35mm from end to end, with an outer diameter of 14.25 mm and wire dia of 2mm.

The pressure plates and bus bar system should be suitable for incoming 50 sq.

mm Aluminum / Copper cable and 35 sq mm Aluminum / Copper cable for outgoing circuits.

4.1.5 ARRANGEMENT OF BUSBARS:

The Bus bar housings shall be arranged and mounted at a suitable stepped

angle so that making new connections is easy and without much bending of the cables. 4.1.6 SEALING OF BOX : The box (enclosure) cover shall have a U clamp sealing system with 2 Nos. Zinc passivated U clamps with holes.

4.1.7 I.P.Level : For protection against ingrace of moisture, Water Particles and Dust etc., the box should meet

with I.P. Level - I.P-55.

a. Neoprene rubber gasket be provided all around the cover . b. The box shall have built in type hinges, no screws/rivets be visible from

outside. 4.1.8 Gland Plate :

At bottom side of the enclosure, a M.S. Hot dip Galvanised 1.2 mm sheet Gland Plate with 10 Nos. of holes is to be provided for one incoming and five outgoing cables from each phase and one incoming and Nine outgoing cables from neutral bus bar as per drawing.

4.1.9 Earthing Plate :

864

The one No. 2 mm thick Hot Dip Galvanised earthing Plate of size indicated in the drawing shall be provided at bottom side of the distribution box to accommodate earthing wire or armour running with cables.

4.1.10 OTHER COMPONENTS & FEATURES:

1. There shall be a provision of one incoming + five outgoing circuits on each of three phase busbars and one incoming + nine outgoing circuits on neutral busbars.

2. One Set (4 nos.) of Busbar moulded casing each containing one set (2 nos.) of busbars and the spring loading system along with pressure plates should be provided.

3. The box shall have built in type hinges, no screws/rivets visible from outside. 4. Neoprene rubber gasket to be provided all around the cover .

4.1.11 Arrangement for mounting of Box on Pole :

The box shall be provided with 2 Nos. of M.S. Hot Dip Galvanised mounting

channels of thickness 1.6 mm and 2 Nos. M.S. Round U–clamps Hot Dip Galvanised with nuts & washers for fixing the Box on the holes. The size of mounting channel and U clamp shall be as specified in the Specification / GTP / Drawing.

5.0 TECHNICAL PARAMETERS FOR SPRING LOADED CONSTANT PRESSURE MULTI CONNECTION BUS BAR DISTRIBUTION BOX FOR THREE PHASE SUPPLY SYSTEM


1 Material of Box (Enclosure)

Glass Filled U.V. Stablised Fire Retardant Nylon 6.6 or UV Resistant Fire Retardant polycarbonate

2 Thickness 3 mm.

3 Dimension of the enclosure

400 x 300 x 190mm ( Min. Internal Dimension)

865


4 Material ofinsulation for mounting Busbar (Bus Bar Supports)


5 No. of circuits both incoming & outgoing in the Busbar

1incoming + 5 outgoing Circuits in each of three phase bus bar 1 incoming + 9 outgoing Circuits in neutral busbar

6 Material ofInsulation for Busbars moulded casing

Nylon Glass filled capable to withstandFire Retardant Test at 9500C as per IECPublication 695–2–1





4 Sets (Three for Phase & One for Neutral).


Each Phase Busbar for 1incoming + 5 outgoing Circuits =125 mm

Neutral busbar for 1 incoming + 9 outgoing Circuits = 210 mm

11 Pressure Plate Thickness 2.0 mm stainless


13 Earthing Plate 1 No 2 mm M.S.Hot Dip Galvanised

14 Earthing Bolt 6 Nos M6 20 mm


16 Distance between Phase & Neutral, phase & phase

Center to Center distance 35 - 40mm

17 Hinges 2 Nos. built in type hinges, No screws/rivets visible from outside.

18 IP Level IP 55

19 Sealing U Clamp 2 Nos. 1.2 mm Zinc passivated.


2 Nos. (1.6 mm Thick sheet steel Hot Dip Galvanised )

866



2 Nos. M.S. Round U Type Clamp Hot DipGalvanised with Nuts & Washers as per dimension indicated in the drawing

22 Gland Plate 1 No. 1.2 mm M.S. Hot Dip Galvanised.

23 Tolerances As per Drawing


50 Sq mm Aluminium cable

25 Suitable for outgoing cable size

6 – 35 Sq mm Aluminium cable

26 Color Grey

27 Marking a) Name or trade mark of manufacturer. b) JPD c) TN-4216

Note: The Nuts & Washers may be Electroplated. 6.1 MARKING :

The following shall be embossed on the cover of box in big font : a) Name or trade mark of the manufacturer. b) JPD c) TN-No./IPDS

7.0 DRAWINGS :

i) The tenderers shall submit with his tender the bill of material and fully dimensional drawing of the offered material clearly showing the full details of material components to be supplied by them to enable the purchaser to examine the offer. The following drawings are appended with this specification:

a) General Arrangement b) U-Clamp c) Bus Bar enclosure earth blade d) Channel for mounting the box on the pole.

ii) The successful bidder will submit the full dimensional drawing on A-3 size paper in triplicate for all the components for approval of purchaser as per specification before commencement of supply. If the successful bidder manufacture the equipment without obtaining approval of drawing, the purchaser will not be responsible if any part is not as per required dimensions. Approval of drawings/ work by Purchaser shall not relieve the Supplier of his responsibility and liability for ensuring correctness and correct interpretation of the latest revision of applicable standards, rules and codes of practices.

867

8.1 TESTS : 8.2 TYPE TESTS :

a) The tenderer should furnish valid type test certificates from Central Power Research Institute (CPRI) or NABL accredited independent test laboratory on similar rating and design of tendered material/equipment i.e. separate type test report for single phase and three phase Spring Loaded Constant Pressure Multi-connection Bus Bar Distribution Box. Tests carried out by tenderer in his own R&D units even if recognized by NABL shall not be accepted except incase of Govt. undertakings.

b) Bidder should also furnish documentary evidence in support of laboratory (Other than CPRI ) whose Type Test reports have been furnished that the said laboratory is NABL accredited laboratory.

c) Such type test certificates should not be older than three years as on the date of bid opening.

8.3 The type tests to be conducted on Spring Loaded Constant Pressure Multi- connection Distribution Box as per relevant IS. The following tests shall constitute the type tests:


1 Visual examination As Per GTP/ approved drawing

2 Verification of dimensions & Marking As Per Spec/GTP/approved drawing

3 Protection against electric Shock IS:14772 9

4 Resistance to ingress of solid object & to harmful ingress of water ( IP-55 )

IS:14772 12


IS:14772 13

6 Resistance to heat IS:14772 14 7 Resistance to Rusting IS:14772 16 8 Glow Wire Test at 950 degree

Centigrade IS:14772/ IEC 695-2-1

9 Verification of Dielectric IS:8623 8.2.2.2

868

S.NO NAME OF TEST STANDARD CLAUSE NO. Properties at 5 KV

10 Heat Deflection Test at 125 degree Centigrade at 0.45 Mpa


IS:4249 3.5.1


13 U V Resistance Test Din 53387

14 Withstand Voltage Test

B FOR BUS BAR



IS:8623-I 8.2.2


IS:11000- 1/IEC 695-2-1

i) IP-55 Test Report for the type of Box (enclosures) specified to be furnished with the tender.

ii) Type test reports of Heat run test on at least one set of Bus Bar either single phase or three phase bus bar with 200A heat run test has to be furnished with the tender.

8.4 The above tests should be carried out on the samples in the order mentioned in relevant IS.


The material shall be subjected at manufacturer's works before despatch to the

routine & acceptance tests given here-under as per relevant IS. 8.6 ACCEPTANCE TESTS :

These tests shall be carried out on the samples taken from the lot for the purpose

of the acceptance of lot which are to be conducted as per relevant IS:


1 Visual examination As Per GTP/ approved drawing 2 Verification of dimensions As Per GTP/ approved drawing

869

S.NO NAME OF TEST STANDARD CLAUSE NO. 3 Protection against electric

Shock IS:14772 9


IS:14772 13

5 Glow Wire Test at 950 degree Centigrade

IS:14772/ IEC 695-2-1


IS:8623 8.2.2.2


IS:4249 3.5.1


B FOR BUSBAR



IS:8623-I 8.2.2


IS:11000- 1/IEC 695-2-1

8.7 ROUTINE TESTS :

These tests are to carried out to check various requirements of Spring Loaded Constant Pressure Multi-connection Distribution system which are likely to vary during production. The following tests shall be conducted / carried out on Spring Loaded Constant Pressure Multi-connection Distribution system by the bidder at his works as per relevant IS and he should furnish certificate / record thereof during pre- despatch inspection:-

i) Verification of dimensions & Marking ii) Protection against electric Shock iii) Test for self extinguishing properties

9.0 TESTS AT SITE :

The purchaser reserves the right to conduct all tests on each type of Spring

Loaded Constant Pressure Multi-connection Distribution system after arrival at site and bidder shall guarantee test certificates figures under actual service conditions.

870


The bidder should possess adequate testing facilities for carrying out routine & acceptance test of item as per relevant standard at their works. The bidder shall furnish documentary evidence in support of conducting routine & acceptance test. The per day capacity of testing facilities at the works of the bidder shall be verified by the representative of the purchaser.

11.1 INSPECTION :

11.2 All the routine /acceptance tests as mentioned above for pre-despatch inspection shall be conducted at the place of manufacturer unless otherwise especially agreed upon by the bidder and purchaser at the time of purchase. The bidder shall afford the inspection officer(s) representing the purchaser all reasonable facilities without charges, to satisfy him that the material is being furnished in accordance with this specification. The purchaser has the right to have the tests carried out at his own cost by an independent agency whenever there is a dispute regarding the quality of supply.

11.3 The inspection may also be carried out by the purchaser at any stage of manufacture / before despatch as per relevant standard.

11.4 Inspection and acceptance of any material under the specification by the purchaser, shall not relieve the bidder of his obligation of furnishing material in accordance with the specification and shall not prevent subsequent rejection if the material is found to be defective. The bidder shall keep the purchaser informed in advance, about manufacturing programme so that arrangements can be made for inspection.

11.5 The purchaser reserves the right to insist for witnessing the acceptance / routine testings of the bought out items.

11.6 The bidder shall give 15 days advance intimation to enable the purchaser to depute his representative for witnessing the acceptance and routine tests. The inspection charges would be to the purchaser's account.



given in Schedule-V(B).

871



13.2 SAMPLING

One sample of each type out of each sub-lot / lot of 500 Nos. or part thereof

from each inspected lot received in stores shall be selected for test checking of material and shall be got tested.

The sample selection shall be done as soon as the material is received in stores, without calling the representative of supplier. However, testing at CTL shall be done in the presence of representative of supplier after identification/ confirmation by the supplier’s representative that sample(s) so selected belong to them.

13.3 TESTS


a) Visual Examination, verification of dimensions and marking as per GTP/

approved drawing.

b) Any other acceptance test for which facility are available in CTL. Checking of material of Box , Busbar, Busbar Casing and Busbar Support.

13.4 Test of the material shall be got done at the test laboratory of the NIGAM For witnessing of the testing, 7 days notice shall be given to the supplier stating date, time & place . In case the supplier do not attend for witnessing the testing, the testing shall be proceeded and completed and action taken as per the contract.

13.5 Officer Incharge of CTL i.e. XEN(CTL) shall send copies of test reports to the purchaser, consignees and the supplier.


In case of failure of sample, the material contained in the lot / sub-lot to which

the sample belongs, shall be rejected. The rejected material shall have to be replaced by the supplier free of cost.

13.7 TEST CHARGES :

All test charges incurred towards test checking of the material received in our

stores shall be borne by the NIGAM.

872

13.8 PAYMENT: i) Payment shall be made only after receipt of successful tests report from the CTL on the samples selected from the material received at the stores.

873

SCHEDULE-V (B)

GUARANTEED TECHNICAL PARTICULARS (G.T.P.) FOR SPRING LOADED CONSTANT PRESSURE MULTI CONNECTION BUS BAR DISTRIBUTION BOX FOR THREE PHASE SUPPLY SYSTEM


1 Manufacturers name& address

2 Place ofManufacture

3 Material of Box (Enclosure)

Glass Filled U.V. Stablised Fire Retardant Nylon 6.6 or UV Resistant Fire Retardant polycarbonate

4 Thickness 3 mm.

5 Dimension of the enclosure

400 x 300 x 190mm ( Min. Internal Dimension)

6 Material ofinsulation for mounting Busbar (Bus Bar Supports)


7 No. of circuits both incoming & outgoing in the Busbar

1incoming + 5 outgoing Circuits in each of three phase bus bar 1 incoming + 9 outgoing Circuits in neutral busbar

8 Material ofInsulation for Busbars moulded casing

Nylon Glass filled capable to withstandFire Retardant Test at 9500C as per IECPublication 695–2–1





4 Sets (Three for Phase & One for Neutral).


Each Phase Busbar for 1incoming + 5 outgoing Circuits =125 mm

Neutral busbar for 1 incoming + 9 outgoing Circuits = 210 mm

874


13 Pressure Plate Thickness 2.0 mm stainless


15 Earthing Plate 1 No 2 mm Hot dip galvanized

16 Earthing Bolt 6 Nos M6 20 mm


18 Distance between Phase & Neutral, phase & phase

Center to Center distance 35 - 40mm

19 Hinges 2 Nos. built in type hinges, No screws/rivets visible from outside.

20 IP Level IP 55

21 Sealing U Clamp 2 Nos. 1.2 mm zinc passivated


2 Nos. (1.6 mm Thick sheet steel Hot dip galvanized)


2 Nos. M.S. Round U Type Clamp Zinc passivated with Nuts & Spring Washersas per dimension indicated in the drawing

24 Gland Plate 1 No. 1.2 mm Hot dip gavanised

25 Tolerances As per Drawing


50 Sq mm Aluminium cable

27 Suitable for outgoing cable size

6 – 35 Sq mm Aluminium cable

28 Color Grey

29 Marking a) Name or trade mark of manufacturer. b) JPD c) TN- No./IPDS

Note: The Nuts & Washers may be Electroplated.

Name of Firm

Signature of Bidder

Designation & Seal

Date

875

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