1. GENERAL 1.1 GUARANTEED TECHNICAL PARTICULARS 1.2 … · 2.0.1 Road Crossings:-At all road crossings, the poles shall be fitted with strain type insulators. The ground clearance

1.GENERAL 1.1 GUARANTEED TECHNICAL PARTICULARS The Contract Works shall comply with the guaranteed technical particulars as per REC/CEA guide lines.

1.2 ERECTION AT SITE AND ACCOMMODATION The Contractor shall provide, at his own cost and expense, all labors, plant and material necessary for

unloading and erection at the Site and shall be entirely responsible for its efficient and correct operation.

The Contractor shall be responsible for arranging and providing all living accommodation services and

amenities required by his employees. 1.3 Use of electrical energy The Contractor shall arrange at his own cost and expense, any site supplies of electrical energy which he

may require for supplying power for heavy erection plant, welding plant or other tools, lighting and testing

purposes.All wiring for such tackle and for lighting from the point of supply shall be provided by the

Contractor and all such installations shall comply with all appropriate statutory regulations.

1.4 RESPONSIBILITY OF THE CONTRACTOR Until each Section of the Contract Works has been taken over or deemed to have been taken over under

the Conditions of Contract, the Contractor shall be entirely responsible for the Contract Works, whether

under construction, during tests, or in use for the Employer‟s service. 1.5 COMPLIANCE WITH REGULATIONS All apparatus and material supplied, and all works carried out shall comply in all respects with such of the

requirements of all Regulations and Acts in force in the country and state in particular of the Employer as

are applicable to the Contract Works and with any other applicable regulations to which the Employer is

subjected to oblige. 1.6 MAINTENANCE AND CLEARING OF SITE The placing of materials and plant near the erection site prior to their being erected and installed shall be

done in a neat, tidy and safe manner. The Contractor shall at his own expense keep the site area allocated

to him and also the erection area of the Contract Works reasonably clean and shall remove all waste

material as it accumulates and as directed by the Engg In-charge from time to time. 1.7 INSURANCE 1.7.1 Worksmen's Compensation Insurance This insurance shall protect the Contractor against all claims applicable under the worksmen‟s Compensation Act, 1948 (Government of India). This policy shall also cover the Contractor against the

claims for injury, disability, disease or death of his or his sub-contractor's employees, which for any reason

are not covered under the Worksmen‟s Compensation Act, 1948. The liabilities shall not be less than; a. Worksmen‟s Compensation- As per statutory provisions a Employee's liability-As per statutory provisions According to the Govt. rules. b Comprehensive automobile insurance This insurance shall be in a such a form to protect the Contractor against all claims for injuries, disability,

disease and death to members of public including the Employer's men and damage to the property of

others arising from the use of motor vehicles during on or off the Site operations, irrespective of the

ownership of such vehicles and as per latest prevailing Govt. rules. d. Comprehensive General Liability Insurance

This insurance shall protect the Contractor against all claims arising from injuries, disabilities, disease or

death of members or public or damage to property of others, due to any act or omission on the part of the

Contractor, its agents, its employees, its representatives and sub-contractors or from riots, strikes and civil

commotion. The hazards to be covered will pertain to all works and areas where the Contractor, its sub-

contractors, agents and employees have to perform works pursuant to the Contracts. 1.7.2 WORKS AND SAFETY REGULATIONS The Contractor shall ensure safety of all the workmen, plant and equipment belonging to him or to others,

working at the Site. The Contractor shall also provide for all safety notices and safety equipment required

by the relevant legislation and deemed necessary by the Engg- In-charge.

1.7.2.1 Drawings Within 07 days of contract commencement the Contractor shall submit, for approval by the SOUTHCO

Utility, a schedule of the drawings to be produced detailing which are to be submitted for "Approval" and

which are to be submitted "For Information Only". The schedule shall also provide a programme of drawing

submission, for approval by the Engineer in charge that ensures that all drawings and calculations are

submitted within the period specified above.

1.1.2 GENERAL PARTICULARS OF SYSTEM

System description

The following are the general particulars governing the design and working of the complete system of

which the Contract Works will eventually form a part: The system is three phase, 50 Hz and power is to

be distributed to consumers under SOUTHCO at appropriate voltage level.

Sl.No. DescriptionofTechnicalParameters Unit

11KV

1 Nominal system voltage KVrms 11 KV

2 Maximumsystem voltage KVrms 12.KV

3 Powerfrequency withstand voltage KVrms 28KV

Lightningimpulsewithstand voltage KVp 75KVp

4 a)Lineto earth 85KVp

b) Acrossisolatinggap

One minutepowerfrequencywithstand value

5 Dry KVrms 35

Wet KVrms

35

6 Systemfrequency Hz 50

7 Variation in frequency % 2.5

8 Continuouscurrentrating Amp 1250

9 Symmetrical short circuit current kA 25

10 Duration of short circuit fault current Sec 3

11 Dynamicshort circuit currentrating kAp

12 Design ambient temperatures ˚C 50

13 Pollution levelas per IEC-815 and 71 III

14 Maximumfault clearingtime Ms

notexceeding

150ms

Safetyclearances

1. Sectionclearance Meters 3 4 2. Groundclearances( betweengroundand

bottom most part of energized object)

i.Alonga streetii. Meters 5.791 5.791

Acrossa street

15 6.096 6.06

3. Horizontalclearancebetween the fence/

building, structure and energized object Meters 3.64

1.2 DATA

1.2.1 METEROLOGICAL

Description Data

Annual mean of maximum monthly average temperature. 50

Annual mean of minimum monthly temperature in ˚C 5

Average rain fall in mm 1500

Average thunder storms days per year 77days

Design ambient temperature in ˚C 50

Maximum wind velocity in meter/sec. 50

Maximum relative humidity in % 100

Average relative humidity in % 85 1.3 GUARANTEES TECHNICAL PARTICULARS

The Contract Works shall comply with the guaranteed technical particulars as per REC/CEA guide lines.

All materials supplied under this Contract shall be to the approval of the Engineer In-charge . 1.4 ERECTION AT SITE AND ACCOMMODATION Use of electrical energy The Contractor shall arrange at his own cost and expense, any site supplies of electrical energy which he

may require for supplying power for heavy erection of materials or other tools, lighting and testing purposes.

All such installations shall comply with all appropriate statutory regulations. 1.5 RESPONSIBILITY FOR THE WORK COMPLETION BY CONTRACTOR Until each Section of the Contract Works has been taken over or deemed to have been taken over under

the Conditions of Contract, the Contractor shall be entirely responsible for the Contract Works, under

construction, or in use for the owner‟s service. 1.6 COMPLIANCE WITH REGULATIONS All apparatus and material supplied, and all works carried out shall comply in all respects with such of the

requirements of all Regulations and Acts in force in the country and state in particular of the owner as are

applicable to the Contract Works and with any other applicable regulations to which the owner is subjected

to oblige. 1.7 MAINTENANCE AND CLEARING OF SITE The placing of materials near the erection site prior to their being erected and installed shall be done in a

neat, tidy and safe manner. The Contractor shall at his own expense keep the site area and erection area

of the Contract Works reasonably clean and shall remove all waste material as it accumulates and as

directed by the Engineer In-charge from time to time.

1.8

The Contractor shall ensure safety of all the workmen, material, equipment belonging to him or to others,

working at the Site. The Contractor shall also provide for all safety notices and safety equipment required

by the relevant legislation and deemed necessary by the Engineers-In charge.

TECHNICAL SPECIFICATION For Construction of 11KV Line,LT line and DP Mounted S/S 1.0 Survey & scope of works:

1.1 Survey shall be carried out by the contractor for the new line. 1.2 Aligning / erection of poles in the route of line along with strengthening of its foundation is in the scope of bidder. 1.3 Before undertaking the construction works in the given line the bidder shall make Assessment of the required materials in consultation /presence of representative of the bidder and accordingly the BOQ of the works is to be get it approved from the Engineer-in charge. 1.4 Any other works not mentioned above exclusively but required for accomplishing desired works will be in the scope of the bidder.

1.5 For all above activities shutdown shall be arranged by the subject to advanced notice in writing by the bidder.

1.6 While placing the equipment, if any equipment gets damaged due to negligent handling of the

contractor, the same shall be back charged to the contractor at panel rate.

2.0 Crossings 2.0.1 Road Crossings:- At all road crossings, the poles shall be fitted with strain type insulators. The

ground clearance from the road surfaces under maximum sag condition shall be as per IS 5613. 2.0.2 Power Line Crossings- Where the line is to cross over another line of the same voltage or lower

voltage, provisions to prevent the possibility of their coming into contact with each shall be made in

accordance with the Indian Electricity Rules, 1956 as amended from time to time. All the works related

to the above proposal shall be deemed to be included in the scope of the contractor. 3.0 Details Enroute-After survey and finalization of route, the contractor shall submit detailedroute map for each line.

This would be including following details:

c) Clearance from Ground, Building, Trees etc. – Clearance from ground, buildings, trees and telephone

lines shall be provided in conformity with the CEA guideline as amended up to date. The bidder shall

select the height of the poles in order to achieve the prescribed electrical clearances. 4.0 Final Schedule-The final schedule including Bill of quantity indicating location of poles

specificallymarking locations of failure containment pole/structure, DTs 11 kV line sectionalizes, line tapping

points angle of deviation at various tension pole locations, all type of crossings and other details shall be

submitted for the approval of the Owner.

3.1 Excavation of Pits

a) For excavation of the foundation pit, a hole should be drilled in the ground preferably with the use of

earth-augers. However, if earth-augers are not available, a pit shall be made in the direction of the line

for all the locations, except the locations of failure containment structures. The minimum planting depth

of poles shall be governed by IS: 1678. However due to the ground conditions e.g. water logged area

etc. depth of planting of poles shall be suitably increased with prior approval of the Engineer In charge. b) Excavation cost for pits shall be included by the contractor in the bid for pole erection for

following type of soils inclusive of dewatering of pits and shorting and shuttering wherever necessary. i) All type of soils and soil conditions including hard rock. ii) Hard rock No separate claim for dewatering during excavation, shoring and shuttering shall be

entertained. For hard rock, the excavation cost per location shall remain same for

all type of foundations. c) In case of non-availability of earth-augers, the pits shall be excavated with pick axes, crow bar and

shovels. Controlled blasting shall be permitted only in case of hard or rocky soil. The contractor shall be

responsible for any damage or accidents arising out of the process of blasting. Blasting is not permitted

if the area around location is inhabited. In such case,

the contractor shall have to follow other methods like drilling etc.

4.0 INSPECTION

All tests and inspection shall be made in the manufacturer‟s works unless otherwise specifically agreed

upon by the manufacturer and purchaser at the time of placement of purchase order. The manufacturer

shall afford to the inspector representing the purchaser, all reasonable facilities, without charge to satisfy

him that the material being furnished is in accordance with these specifications. The purchaser reserves the

right to get an component/material being used by the manufacturer tested from any recognized test house. The inspection by the purchaser or his authorized representative shall not relieve the contractor of his

obligation of furnishing equipment in accordance with the specifications.

TECHNICAL SPECIFICATIONS THE SPECIFICATION OF ALL MAJOR MATERIAL SHALL BE AS PER REC STANDARDS

All materials, which are to be supplied by the contractor,

should be procured from the approved Vendors of Southco

utility. Procurement from any other suppliers will not be-----

PSC Pole (8 Mtr. x 200 Kg & 9 Mtr. x 300 Kg) TECHNICAL SPECIFICATIONS

1. Applicable Standard :

The Poles shall comply with latest standards as following:

a) REC Specification No. 15/1979, REC Specification No. 24/1983 b) IS 1678, IS 2905, IS 7321

2. Materials :

Cement

The cement used in the manufacture of pre-stressed concrete poles shall be ordinary for rapid hardening Portland cement confirming to IS: 269-1976 (Specification for ordinary and low heat Portland cement) or IS: 8041 E-1978 (Specification for rapid hardening Portland cement).

Aggregates

Aggregates used for the manufacture of pre-stressed concrete poles shall confirm to IS: 383 (Specification for coarse and fine aggregates from natural sources for concrete) .The nominal maximum sizes of aggregates shall in no case exceed 12 mm.

Water

Water should be free from chlorides, sulphates, other salts and organic matter. Potable water will be generally suitable.

Admixture

Admixture should not contain Calcium Chloride or other chlorides and salts which are likely to promote corrosion of pre-stressing steel. The admixture shall conform to IS: 9103.

Pres-Stressing Steel

The pre-stressing steel wires including those used as un tensioned wires should conform to IS:1785 (Part-I) (Specification for plain hard-drawn steel wire for pre-stressed concrete, Part-I cold drawn stress relieved wire).IS:1785 (Part-II)(Specification for plain hard-drawn steel wire) or IS:6003 (Specification for indented wire for pre-stressed concrete).The type design given in the annexure are for plain wires of 4 mm diameter with a guaranteed ultimate strength of 160 kg/mm².

All pre-stressing steel shall be free from splits, harmful scratches, surface flaw, rough, aged and imperfect edges and other defects likely to impair its use in pre-stressed concrete.

Concrete Mix

The concrete mix shall be designed to the requirements laid down for controlled concrete (also called design mix concrete) in IS: 1343-1980 (Code of practice for pre-stressed concrete) and IS: 456 – 1978 (Code of practice for plain and reinforced concrete) subject to the following special conditions:

a) Minimum works cube strength at 28 days should be at least 420 Kg/cm². b) The concrete strength at transfer should be at least 210 Kg/cm². c) The mix should contain at least 380 Kg of cement per cubic meter of concrete. d) The mix should contain as low water content as is consistent with adequate workability.

It becomes necessary to add water to increase the workability the cement content also should be raised in such a way that the original value of water cement ratio is maintained.

3. Design Requirements

The poles shall be designed for the following requirements:

The poles shall be planted directly in the ground with a planting depth as per IS: 1678. Wherever, planting depth is required to be increased beyond the specified limits or alternative arrangements are required to be made on account of ground conditions e.g. water logging etc., the same shall be in the scope of the bidder at no extra cost to owner. The bidder shall furnish necessary design calculations/details of alternative arrangements in this regard.

The working load on the poles should correspond to those that are likely to come on the pole during their service life.

The factor of safety for all poles 9.0Mts.Shall not be less than 2.0 and for 8.0 M poles, the factor of safety shall not be less than 2.5.

The average permanent load shall be 40% of the working load. The F.O.S. against first load shall be 1.0. At average permanent load, permissible tensile stress in concrete shall be 30 kg/cm². At the design value of first crack load, the modulus of rupture shall not exceed

53.0kg/cm² for M-40. The ultimate moment capacity in the longitudinal direction should be at least one

fourth of that in the transverse direction. The maximum compressive stress in concrete at the time of transfer of pre-stress

should not exceed 0.8 times the cube strength. The concrete strength at transfer shall not be less than half, the 28 days strength

ensured in the design, i.e. 420x0.5=210kg/cm².

For model check calculations on the design of poles, referred to in the annexure, a reference may be made to the REC “Manual on Manufacturing of solid PCC poles, Part-I- Design Aspects”.

4 Dimensions and Reinforcements

The cross-sectional dimensions and the details of pre-stressing wires should conform to the particulars given in the enclosed drawing NH/RE/PSC/01.

The provisions of holes for fixing cross-arms and other fixtures should conform to the REC specification No. 15/1979.

5 Manufacture

All pre-stressing wires and reinforcements shall be accurately fixed as shown in drawings and maintained in position during manufacture. The un-tensioned reinforcement as indicated in the drawings should be held in position by the use of stirrups which should go round all the wires.

All wires shall be accurately stretched with uniform pre-stressed in each wire. Each wire or group of wires shall be anchored positively during casing. Care should be taken to see that the anchorages do not yield before the concrete attains the necessary strength.

6 Cover

The cover of concrete measured from the outside of pre-stressing tendon shall be normally 20 mm.

7 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, joining or coupling may be permitted provided the strength of the joint or coupling is not less than the strength of each individual wire.

8 Compacting Concrete shall be compacted by spinning, vibrating, shocking or other suitable mechanical means. Hand compacting shall not be permitted.

9 Curing

The concrete shall be covered with a layer of sacking, canvass, Hessian or similar absorbent material and kept constantly wet up to the time when the strength of concrete is at least equal to the minimum strength of concrete at transfer of pre-stress. Thereafter, the pole may be removed from the mould and watered at intervals to prevent surface cracking of the unit the interval should depend on the atmospheric humidity and temperature.

The pre-stressing wires shall be de-tensioned only after the concrete has attained the specified strength at transfer (i.e. 200 or 210 kg/cm² as applicable).The cubes cast for the purpose of determining the strength at transfer should be coursed, a sear as possible, under condition similar to those under which the poles are cured. The transfer stage shall be determined based on the daily tests carried out on concrete cubes till the specified strength indicated above is reached. Thereafter the test on concrete shall be carried out as detailed in IS: 1343(code of practice for pre-stressed concrete). The manufacture shall supply, when required by the owner or his representative, result of compressive test conducted in accordance with IS: 456 (Code of practice for plain and reinforced concrete) on concrete cubes made from the concrete used for the poles. If the manufacture so desired, the manufacture shall supply cubes for test purpose and such cubes shall be tested in accordance with IS: 456 (Code of practice for plain and reinforced concrete).

10 Lifting Eye-Hooks or Holes

Separate eye-hooks or hoes shall be provided for handling the transport, one each at a distance of 0.15 times the overall length, from either end of the pole. Eye-hooks, if provided, should be properly anchored and should be on the face that has the shorter dimension of the cross-section. Holes, if provided for lifting purpose, should be perpendicular to the broad face of the pole.

11 Holes for Cross Arms etc

Sufficient number of holes shall be provided in the poles for attachment of cross arms and other equipments.

12 Stacking & Transportation

Stacking should be done in such a manner that the broad side of the pole is vertical. Each tier in the stack should be supported on timber sleeper located as 0.15 times the overall length, measured from the end. The timber supported in the stack should be aligned in vertical line.

13 Earthing

Earthing shall be provided by having length of 8 SWG GI wire embedded in Concrete during manufacture and the ends of the wires left projecting from the pole to a length of 100mm at 250 mm from top and 150 mm below ground level.

Earth wire shall not be allowed to come in contract with the pre-stressing wires.

TECHNICAL SPECIFICATION

HT & LT STAY SETS

1.0 SCOPE

This specification covers design, manufacture, testing and dispatch of GI Stay Sets of 16

mm and 20 mm dia.

2.0 GENERAL REQUIREMENTS

2.1 16 MM Dia Stay sets (Galvanized) – LT Stay Set

This stay sets (Line Guy set) will consist of the following components:-

2.1.1. Anchor Rod with one washer and Nut

Overall length of rod should be 1800 mm to be made out of 16 mm dia GS Rod, one end

threaded up to 40 mm length with a pitch of 5 threads per cm and provided with one

square GS washer of size 40X40x1.6mm and one GS hexagonal nut conforming to

IS:1367:1967 & IS:1363:1967. Both waster and nut to suit threded rod of 16 mm dia. The

other end of the rod to be made into a round eye having an inner dia of 40mm with best

quality welding.

2.1.2. Anchor Plate Size 200 x 200 x6 mm

To be made out of GS plate of 6 mm thickness. The anchor plate should have at its centre

18 mm dia hole.

2.1.3 Turn Buckle & Eye Bolt with 2 Nuts

To be made of 16 mm dia GS Rod having an overall length of 450mm, one end of the rod to

be threaded up to 300 mm length with a pitch of 5 threads per cm and provided with two GS

Hexagonal nuts of suitable size conforming toIS:1363:1967 & IS:1367:1967. The other end of rod shall be rounded into a circular eye of 40mm inner

dia with proper and good quality welding.

2.1.4. Bow with Welded Angle

To be made out of 16mm dia GS rod. The finished bow shall have an over all length of

995 mm and eight of 450 mm, the apex or top of the bow shall be bent at an angle of 10

R. The other end shall be welded with proper and good quality welding to a GS angle

180 mm long having a dimension of 50x50x6mm. The angle shall have 3 holes of 18 mm

dia each.

2.1.5 Thimble

To be made on 1.5 mm thick GS sheet into a size of 75x22x40mm and shape as per

standard shall be supplied.

Average Weight of Finished 16mm Stay Sets shall be at least 7.702 KG (Minimum)

(Excluding Nuts Thimbles and Washer) 8.445 Kg. (Maximum)

2.2 20 mm Dia Stays Sets for 11 KV,33 KV Lines (Galvanized) HT Stay Set

The Stay Set (Line Guy Set) will consist of the following components:

2.2.1 Anchor Rod with one Washer and Nut

Overall length of Rod should be 1800mm to be made out of 20 mm dia GS Rod, one end

threaded up to 40 mm length with a pitch of threads per cm. And provided with one

square G.S. Washer of Size 50x50x1.6mm and one GS Hexagonal nut conforming to IS:

1363:1967 & IS:1367:1967. Both washer and nut to suit the threaded rod of 20mm. The

other end of the rod to be made into a round eye having an inner dia of 40mm with best

quality welding. Dimensional and other details are indicated and submitted by bidders for

owner‟s approval before start of manufacturing.

2.2.2 Anchor Plate Size 300 x 300 x 8 mm

To be made out of G.S. Plate of 8 mm thickness. The anchor plate 3+ to

have at its centre 22mm dia hole.

2.2.3 Turn Buckle, Eye Bolt with 2 Nuts.

To be made of 20 mm dia G.S. Rod having an overall length of 450 mm. One end of the

rod to be threaded up to 300 mm length with a pitch of 4 threads per cm. The 20 mm dia

bolt so made shall be provided with two G.S. Hexagonal nuts of suitable size conforming

to IS: 1363:1967 & IS: 1367:1967.

The other end of the rod shall be rounded into a circular eye of 40mm inner dia with

proper and good quality of welding. Welding details are to be indicated by the bidder

separately for approval.

2.2.4 Bow with Welded Channel:

To be made out of 16mm dia G.S.Rod. The finished bow shall have and overall length of

995 mm ad height of 450 mm. The apex or top of the bow shall be bent at an angle of

10R. he other end shall be welded with proper and good quality welding to a G.S.

Channel 200 mm long having a dimension of 100x50x4.7 mm.

The Channel shall have 2 holes of 18 mm dia and 22 dia hole at its centre as per drawing

No.3 enclosed herewith.

2.2.5 Thimble 2 Nos.

To be made of 1.5 mm thick G.S sheet into a size of 75x22x40mm and shape as per

standard.

2.2.6 Galvanizing

The complete assembly shall be hot dip galvanized as per ISS.

2.2.7. Welding

The minimum strength of welding provided on various components of 16mm and 20 mm

dia stay sets shall be 3100 kg & 4900 kg respectively. Minimum 6mm filet weld or its

equivalent weld area should be deposited in all positions of the job i.e. at any point of the

weld length. The welding shall be conforming to relevant IS:823/1964 or its latest

amendment.

2.2.8. Threading

The threads on the Anchor Rods, Eye Bolts and Nuts shall be as per specification IS;

4218:1967 (ISO Metric Screw Threads). The Nuts shall be conforming to the

requirements of IS: 1367:1967 and have dimension as per IS 1363:1967. The mechanical

property requirement of fasteners shall confirm to the properly clause 4.6 each for anchor

rods and Eye bolt and property clause 4 for nuts as per IS: 1367:1967.

Average weight of finished 20 mm Stays Set: 14.523 Kg.(Min) (Excluding Nuts Thimble

& Washer) :15.569 Kg. (Max.)

3.0 TESTS

The contractor shall be required to conduct testing of materials at Govt./Recognized

testing laboratory during pre-dispatch inspection for Tensile Load of 3100 Kg/4900Kg.

applied for one minute on the welding and maintained for one minute for 16 mm and

20mm dia stay sets respectively.

4.0 IDENTIFICATION MARK

All stay sets should carry the identification mark of the Purchaser

(NESCO/WESCO/SOUTHCO) as applicable. This should be engraved on the body of

stay rods to ensure proper identification of the materials.

The nuts should be of a size compatible with threaded portion of rods and there should be

not play or slippage of nuts.

Welding wherever required should be perfect and should not give way after erection.

5.0 TOLERANCES

The tolerances for various components of the stay sets are indicated below subject to the

condition that the average weight of finished stay sets of 16mm dia excluding nuts,

thimbles and washers shall not be less than the weight specified above:-

HT / LT STAY SETS

GURANTEED TECHNICAL PARTICULARS

Item Specified

Sl Descript Paramete

No. ion rs Section Type of stay Bidder’s offer Tolerance Fabrication sets

s Tolerances

Mate

rial

1. Anchor 6mm thick 200x200mm GS Plate 6 LT Stay Set

Plate +2.5%-5% +1%

mm

thick

8mm

GS

Plate 8 HT Stay Set

thick+2.5 300x300mm

mm

thick

%-5% +1%

2. Anchor 16mmdia Length GS Round LT Stay Set

Rod +5%- 3% 1800mm+0.

16mm

dia

5%

GS

Round

Rounded

16mm

dia

Eye 40 mm

HT Stay Set

20mm dia inside dia +

GS

Round

+3%-2% 3%

20mm

dai

Threading

GS

Round

40mm

20mm

dia

+11%-5%

Length

1800mm

+0.5%

Round Eye

40mm

inside dia +

3%.

Threading

40mm

+11%-5%

3. Turn 16mm dia Length GS Round LT Stay Set

Buckle +5%-3% 995mm

16mm

dia.

Bow +1% 16mm

HT Stay Set

dia

GS

Angle

Length180

mm +1% G S

50x50x6mm

Chann

el

100x50

x4.7

Channel mm

length

200mm +

1%

4. Eye Bolt 16mm dia Length GS Round LT Stay Set

Rod +5%-3% 450mm +

16 mm

dia

1%

Threading

300mm

HT Stay Set

20mm dia +1% Round

GS

Round

+ 3% -2% Eye 40mm

20mm

dia.

inside

dia+3%

Length450

mm +1%

Threading

300mm

+1% Round

Eye 40 mm

inside dia

+3%

5 Galvanis LT Stay Set

ation

thickness HT Stay Set

a Anchor LT Stay Set

Plate

HT Stay Set

b Anchor LT Stay Set

Rod

HT Stay Set

c Turn LT Stay Set

Buckle

Bow HT Stay Set

d Eye Bolt LT Stay Set

Rod

HT Stay Set

6 Weight LT Stay Set

of

complete

HT Stay Set

set

7 Whether

drawing

submitte

d

TECHNICAL SPECIFICATIONS

STAY WIRE (7/8, 7/10 & 7/12 SWG)

1.0 Application Standards

Except when they conflict with the specific requirements of this specification, the

G.I Stay Stranded Wires shall comply with the specific requirements of IS: 2141-

1979. IS: 4826-1979 & IS: 6594-1974 or the latest versions thereof.

2.0 Application and Sizes

a) The G.I. stranded wires covered in this Specification are intended for use on

the overhead power line poles, distribution transformer structures etc.

b) The G.I stranded wires shall be of 7/8 SWG (7/mm for 33 KV lines, 7/10SWG

(7/3.15 mm for 11KV lines and 7/12 SWG 7/2.5 mm for LT lines standard

sizes.

3.0 Materials

The wires shall be drawn from steel made by the open hearth basic oxygen or

electric furnace process and of such quality that when drawn to the size of wire

specified and coated with zinc, the finished strand and the individual wires shall

be of uniform quality and have the properties and characteristics as specified in

this specification. The wires shall not contain sulphur and phosphorus exceeding

0.060% each.

3.1 Tensile Grade

The wires shall be of tensile grade 4, having minimum tensile strength of 700

N/mm² conforming to 1S:2141.

3.2 General Requirements

a) The outer wire of strands shall have a right-hand lay.

b) The lay length of wire strands shall be 12 to 19 times the strand diameter.

3.3 Minimum Breaking Load & Galvanising

The minimum breaking load of the wires before and after stranding shall be as

follows:

Min. breaking

load of the

Single wire Min. breaking load

No. of Wires Wire Dia before of the standard

& Const. (mm) stranding (KN) wire (KN)

7 (6/1) 2.5 3.44 21.40

7 (6/1) 3.15 5.46 34.00

7 (6/1) 4.0 8.80 54.9 Minimum

weight of

490 gm/mm2 490 gm/mm2 490 gm/mm2 zinc coating

before

stranding

Minimum

weight of

475 gm/mm2 475 gm/mm2 475 gm/mm2 zinc coating

before

stranding

4.0 Construction

a) The galvanized stay wire shall be of 7-wire construction. The wires shall be so

stranded together that when an evenly distributed pull is applied at the ends of

completed strand, each wire shall take an equal share of the pull.

b) Joints are permitted in the individual wires during stranding but such joints

shall not be less than 15 metres apart in the finished strands.

c) The wire shall be circular and free from scale, irregularities, imperfection,

flaws, splits and other defects.

5.0 Tolerances

A tolerance of (+) 2.5% on the diameter of wires before stranding shall be

permitted.

6.0 Sampling Criteria

The sampling criteria shall be in accordance with IS :2141.

7.0 Tests on Wires before Manufacture

7.1 The wires shall be subjected to the following tests in accordance with IS :2141.

a) Ductility Test b) Tolerance on Wire Diameter

7.2 Tests on Completed Strand

The completed strand shall be tested for the following tests in accordance

with IS:2141.

a) Tensile and Elongation Test: The percentage elongation of the

stranded wire shall not be less than 6%.

b) Chemical analysis

c) Galvanizing Test

The Zinc Coating shall conform to "Heavy Coating" as laid down in 1S:4826

8.0 Marking

Each coil shall carry a metallic tag, securely attached to the inner part of the coil

bearing the following information:

a) Manufacturers name or trade mark

b) Lot number and coil number

c) Size

d) Construction

e) Tensile Designation

f) Lay

g) Coating

h) Length

i) Mass

j) ISI certification mark, if any

9.0 Packing

The wires shall be supplied in 75-100 Kg. coils. The packing should be done in

accordance with the provisions of IS:6594

10.0 Other Items:

For remaining items of stay sets mentioned in the enclosed drawing, relevant

applicable Indian standards shall be applicable.


STAY WIRE (7/8, 7/10 & 7/12 SWG)

Sl. GENERAL TECHNICAL

No. PARTICULARS 7/8 SWG 7/10 SWG 7/12 SWG

1 Nominal diameter of wire

2 Tolerance in diameter

3 Sectional Area (In Sq. mm.)

4 Tensile strength

a Min. N/mm²

b Max. N/mm²

5 Minimum breaking load (KN)

6 Type of coating Heavy/Medium/Light

7 Variety Hard/Soft

8 Weight of Zinc coating (Gms/Sq. Mtr.)

Min.

9 No. of dips the coating is able to withstand

as 18 ± 20ºC

10 Adhesion Test (Wrap Test at 1 turn per

second coiling while stress not exceeding

% nominal tensile strength)

a Min. complete turn of wrap

b Dia of mandrel on which wrapped

11 Bend Test

a Angle

b Dia round a format to be bent

12 Freedom from defect

13 Chemical composition the MS Wire used

shall not exceed

a Sulphur 0.060%

b Phosphorous 0.065%

TECHNICAL SPECIFICATIONS

GI WIRE 6 SWG & GI WIRE 8 SWG

1. SCOPE

This specification covers manufacture, testing and supply of hot dip galvanized

MS solid wire of sizes 6 SWG (5 MM) & 8 SWG (4 MM) diameters.

2. APPLICABLE STANDARDS

02.1 ZINC

Zinc shall conform to grade Zen 98 specified in IS 209& IS: 4826-1979 with upto

date amendments.

02.2 ZINC COATING

Zinc coating shall be in accordance with IS: 4826-1979 for heavily coated hard

quality.

02.3 GALVANISING

Galvanizing shall be as per IS:2629-1966, IS 4826-1979 with up to date

amendments

02.4 UNIFORMITY OF ZINC COATING

Uniformity of zinc coating shall be as per IS:2633-1972 with up to date

amendments

02.5 TENSILE PROPERTIES

The tensile strength of the wire after galvanizing shall be between 55-95

Kg/sq.mm ensuring MS wire mechanical properties as per IS-28:1972 8.1 to 8.3.

02.6 FREEDOM FROM DEFECTS

As per IS:2629-1966 & 4826-1979 & with up to date amendments be ensured

3. MATERIAL

The mild steel wire shall have chemical composition maximum sulphur- 0.055%,

phosphorous -0.055%, Carbon 0.25%.

4. TESTS

During the process of manufacturer/fabrication and all tests for chemical,

mechanical, galvanizing as per IS-280-1979, IS1521-1972, IS-1755-1961,

IS:6745-1972 & 4826-1979 shall be carried out. The certificate towards, chemical

composition shall be submitted for each lot offered for inspection.

The following tests shall be conducted in presence of the representative of the

purchaser:

1. Visual physical inspection and measurement of specified dimension 2. Coating test as per IS:1755-1961, IS 2629-1966, IS:2633-1972, IS:4826-

1969

3. Adhesion test as per IS:1755-1961,IS:2629-1966,IS:2633-1972,IS:4826-

1969,&IS:6745-1972

4. Tensile strength and breaking load and elongation determined as per

IS:1521-1972 with up to date amendments

5. PACKING & MARKING

Packing shall be as per IS:280-1979 and each coil shall be between 50-100 kg .marking shall be as per IS:280-1972


GI WIRE 6 SWG & GI WIRE 8 SWG

Sl.

No. GENERAL TECHNICAL PARTICULARS 6 SWG 8 SWG


2 Tolerance in diameter

3 Sectional Area (In Sq. mm.)

4 Tensile strength

a Min. N/mm²

b Max. N/mm²

5 Minimum breaking load (KN)

6 Type of coating Heavy/Medium/Light

7 Variety Hard/Soft

8 Weight of Zinc coating (Gms/Sq. Mtr.) Min.

9 No. of dips the coating is able to withstand as 18 ±

20ºC

10 Adhesion Test (Wrap Test at 1 turn per second

coiling while stress not exceeding % nominal

tensile strength)

a Min. complete turn of wrap

b Dia of mandrel on which wrapped

11 Bend Test

a Angle

b Dia round a format to be bent

12 Freedom from defect

13 Chemical composition the MS Wire used shall not

exceed

a Sulphur 0.060%

b Phosphorous 0.065%

HT STAY INSULATOR & LT STAY INSULATORS


(To be submitted along with offer)

Sl. Description OWNER‟s Bidder‟s Offer No. Approved

Standard

1 Manufacturer‟s name

2 Address of manufacturer

3 Location of type testing

4 Applicable standard & Type

5 Type of insulator (Porcelain or toughened

glass)

6 Dry impulse withstand voltage

7 Wet power frequency, 1 minute,

withstand voltage

8 Dry, Critical Impulse Flashover Voltage

9 Dry, power frequency, Critical Flashover

Voltage

10 Wet, power frequency, Critical Flashover

Voltage

11 Power frequency Puncture Voltage

12 Safe Working Load

13 Minimum Failing Load

14 Creepage Distance

15 Protected Creepage Distance

16 Type and Grade of Materials : Insulator

17 Colour of Insulator

18 Weight of Insulator

19 Number of Insulators per Crate

20 Type of semi conducting Glaze

21 Minimum dia of Stay wire hole

22 Whether drawing showing dimensional

details have been furnished along with

Bid

23 Whether Type Test Certificate have been

furnished

24 Other particulars (if any)

LT Distribution Box

Technical Specifications

& SCOPE

1.1 This specification covers design, manufacture, testing at manufacturer works before

dispatch and supply of L.T. Distribution Cabinet suitable for outdoor installation in Pole mounted /Plinth Mounted distribution sub-stations of following capacity.

i) L.T. Distribution Cabinet for 25KVA,63 KVA & 100KVA 11/0.433KV Transformer

1.2 The Technical Specification contained herein are for the guidance of the bidders, Any

deviation from the Purchasers specification will be considered on their relative merits from the consideration of performance, efficiency, reliability and overall economy consists with the requirements stipulated herein.

c) COMPLETENESS OF CONTRACT:

All fittings or accessories no specifically mentioned herein but necessary or usual for similar equipment and their efficient working shall be provided by the contractor without extra charges.

c) ATMOSPHERIC CONDITIONS:

a) Maximum temperature of air in shade 450C

b) Minimum temperature of air in shade 00C

c) Maximum temperature of air in sun 500C

d) Maximum humidity 100% e) Average number of thunder storm days per annum 70days f) Average number of dust storm days per annum 20 days g) Maximum rainfall per annum 2000mm h) average rainfall per annum 1500mm

i) Maximum ambient temperature daily average 450 C

j) wind pressure 200Kg/M2 k) Altitude Less than 1000m

d) DESCRIPTION OF MATERIALS

The L.T. Distribution cabinets are meant for installation in the D.P. Structure plinth Mounted/Pole Mounted Distribution 11/433 KV substation of the ratings indicated above. These Distribution Cabinets are to be outdoor type and to be fabricated out of 2 mm CR sheet steel duly acid treated and finished with one coat anticorrosive primer and two coats of gray epoxy paint. The body of the boxes shall have sufficient reinforcement with suitable size of channels keeping a provision for fixing these boxes either on DP structure or plinths.

The Box shall have double door with locking arrangement and a door handle conforming to IS 8623/1977 .The roof of the box shall be slightly slanting both sides as per drawing with an over hang of 50mm to the front and back side. For maintenance point of view doors may be provided front side as per the requirement. The nuts, bolts , washers used in the box shall be galvanized to avoid rusting. The door hinges shall not be visible from outside. The box shall have a solid earthing point and arrangement for sufficient ventilation.

The boxes should confirm to IP 54 degree of protection. The bidders shall have to enclose type test certificate for degree of protection (P-54) after their product duly tested at CPRI failing which their bid is liable for rejection. Preference

The box shall have provision of bus bars of Electrolytic Cooper mounted on epoxy resin cast bus insulators fixed on suitable fixing arrangement. The bus bars shall be conveniently placed so as to provide adequate clearance from the body of the box conforming to I.E. Rules applicable for L.T. supply. There should be heat shrinkable bus bar insulation tubing on the busbars.

The arrangement and dimensions shall be as per the drawing enclosed.

The box shall consist of one incoming MCCB and 2 sets of Kit-kat fuse unit for out going feeders.

Suitable cable glands of heavy duty, double compression type shall be provided at the bottom of the box. One for incoming cable and two/three for outgoing cables, Detachable plates shall be provided for fixing of cable glands

Sl. No. Dimension

25 KVA Dist 63 KVA Dist 100 KVA Dist

Box Box Box

1 Height of Box 700 mm 1000 mm 1000 mm 2 Length of Box 600 mm 800 mm 800 mm 3 Width of Box 400 mm 500 mm 500 mm 4 Ventilator Length 250mm 250mm 250mm 5 Ventilator Width 170mm 170mm 170mm 6 MCCB terminal 3x1/2x50 3x1/2x70 mm

2 3x1/2x 95 mm

2

suitable for mm2 cable cable cable

7 Kit Kat terminal 3x1/2x50 mm2

3x1/2x70 mm2

3x1/2x 95 mm2

suitable for cable cable cable

8 Bus Bar 25x5 mm 40x5 mm 40x6 mm 9 Bus Bar materials Electrolytic Electrolytic Electrolytic

Aluminium Aluminium Aluminium

A neutral Busbar similar to phase Busbar is to be provided.

KIT KAT FUSE UNIT : Shall be of reputed make as per IS-

2086 (make- Anchor/Havells/ Ripcon )

The kit kats should have 500 V rating. All contact parts are plated and made of copper and brass with A class porcelain with extended terminal fitted with slots hex bolts with nuts.

The outgoing terminal of the cables is to be connected to the extended terminal of the kit kat by Bimetallic lugs, duly crimped with Die less crimping tools.

MCCB OF REPUTED MAKE : (Make must be specified in the bid)

THE MCCB SHOULD CONFORM TO THE FOLLOWING


i) Standard IS 13947 (Part-2) /1993 & IEC Pub -947 -2 (1989) ii) Rated voltage 415 vol. Ac iii) No. of poles 3 iv) Utilisation category A v) Rated service short

circuit breaking capacity: The percentage of rated service short circuit breaking capacity (I.Cs) to rated ultimate circuit breaking capacity (icu)

shall be mentioned as per IS 13947 (Part- 2) /1989.

vii) Type of protection:-

Overload protection is a must with static /electro magnetic /thermo magnetic trip release.

The terminal capacity of the MCCBs should be such as to accommodate the required LT cable. The incoming cable should be connected to the terminals of the M.C.C.B. with Bi- metallic lugs preferably of Usha Martin/Dowel make duly crimped with Die press& crimping tools. There should be a metallic /heat resistant insulating barrier between the MCCB side & that of kit kat fuses so that the heat generated in Kit Kat fuses carrying current and during fuse blow should not pass to the MCCB.

d) GENERAL

The L.T. distribution Boxes should be of the dimensions as per the

details given above. The bidders can quote with their own design suitably accommodating the components in conforming to the approved clearances and technical requirement as indicated in this bid. The dimensions are only illustrative. Tolerances of dimensions are 10% over & above the dimensions specified. The bidder may specify their own dimensions within + 10% limit and quote accordingly.

The distribution boxes shall be duly wired with suitable size of PVC insulated single core copper cable or equivalent section copper/aluminum flat.

Terminal connectors for the earth connections to be provided in the box.

The distribution cabinet should be preferably of IP-54 protective category, with provision for lighting inside the cabinet. NESCO & Sl. No. Punching Marks should be given on any one of the side walls of each box as an identification of NESCO property, besides furnishing

a non-detachable name plate which should exhibit the details of L.T. Distribution Cabinet.

j) The bidders are required to furnish the Guaranteed Technical Particulars in the format given.

k) TESTS:

The M.C.C.B. to be mounted with Distribution Boxes shall have been fully type tested as per the relevant standard in any NABL approved Testing Laboratory. Copies of type test reports must be enclosed with the tender failing, which the bid is liable for rejection. Purchaser reserves the right to demand repetition of the tests without any extra cost.

l) INSPECTION: -

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 under the 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 is found to be defective.

The supplier shall keep the Purchaser informed in advance about the manufacturing programme so that arrangement can be made for inspection. The purchaser reserves the right to insist for witnessing the acceptance/routine testing of the bought out items.

2. ACCEPTANCE AND ROUTINE TESTS:-

All acceptance and routine tests as stipulated in the relevant standards shall be carried out by the supplier in presence of owner’s representative.

Immediately after finalization of the programme of type/acceptance/routine testing, the supplier shall give fifteen days advance intimation to the Purchaser to enable him to depute his representative for witnessing the tests.

3. DOCUMENTATION: -

The Bidder shall furnish following drawings along with the offer.

General outline and assembly drawing of the L.T. Distribution Box. Cross Sectional view. Arrangement of terminals & details of connection studs provided. Name plate. Schematic drawing. Type test reports MCCB & Distribution box. Test reports, literature of the bought out items and raw materials. Testing facilities available at the works. List of customers with detailed address/purchase reference, quantity and year of supply with user certificate for such items.

Guaranteed Technical Particulars of LT Dist.box

Slno. Description Bidder’s Offer

25KVA

63KVA 100KVA

1 Rated voltage & type

2 Thickness of enclosure

3 Size of Bus bar

Phase

Neutral

4 Bus bar material

5 Over all dimension of board

LXWxH

6 Bus bar supporting insulator

7 Degree of protection

8 Standard followed

9 Terminal capacity

10 Gland Size Inlet/outlet

11 Separation barrio MCCB & Kit-Kat

MCCB

12 Name of Manufacturer

13 Type/code No

14 Rated Current

15 No of Poles

16 Standard followed

17 Utilization Category

18 Rated short circuit Breaking capacity

19 Rated ultimate short circuit Breaking

capacity

20 Type of Protection provided

21 Extra Preference if any

FUSE

22 Make & voltage

23 Rating

24 Terminal Capacity

25 Wiring detail from bus bar to kit kat

fuse

D R A W I N G f o r L . T D i s t r i b u t i o n B o x f o r 25K VA 6 3 K V A , 1 0 0 K V A Transformers

N.B : Separate terminal bar to be provided for Neutral connection. LT Distribution Box for 11/0.23, 16 KVA & 11/0.4, 16 KVA DTR As per REC Specification and latest BIS

AB CABLE ACESSORIES

TECHNICAL SPECIFICATION FOR INSULATION PIERCING CONNECTORS

(IPC),CONDUCTOR DEAD END CLAMP (ANCHOR), SUSSPENSION CLAMP,NEUTRAL

CONNECTOR & EYE HOOK FOR AERIAL BUNCHED CABLES FOR WORKING VOLTAGE UPTO AND INCLUDING 1100 VOLTS SHALL BE AS PER REC SPECIFICATION

NO.32/1884 & AMMENDED NO.83 & 84 /2010 ( WHICH HAS BEEN CIRCULATED BY REC

VIDE THEIR LETTER NO.2464 & 2463 ALL DATED 11.02.2010 RESPECTIVELY OR ANY

LATEST AMMENDED.

1.0 Scope

This specification covers the design, manufacture, assembly, testing and supply of Insulation

Piercing Connectors (IPC), Suspension Clamp, Dead end Clamp, Eye hook, and Neutral connector for making connections to Aerial Bunched Cables rated 1100 volts and insulated with cross-linked

polyethylene.

2.0 Standard

The design, performance and test requirements shall confirm to this specification and the following standards. However in case of any conflict, the requirements of this specification shall prevail.

& REC Specification 32/1984

& REC Specification 83/2010( Insulation Piercing Connectors)

& REC Specification 84/2010 (dead end & Suspension clamp)

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.

3.0 Cable Data

The standard sizes and characteristics of the phase and street lighting conductors, bare messenger wires shall be as specified in IS: 14255-1995 and REC Specification 32/1984 of following sizes

d) 3x95 (Insulated Phase)+1x70(Bare Messenger)+1x16(Insulated street lighting) sq.mm

e) 3x50 (Insulated Phase)+1x35(Bare Messenger)+1x16(Insulated street lighting) sq.mm

f) 3x50 (Insulated Phase)+1x35(Bare Messenger) sq.mm

g) 3x50 (Insulated Phase)+1x35(Bare Messenger ) sq.mm

h) 2x50 (Insulated Phase)+1x35(Bare Messenger ) sq.mm

1

4.0 Insulation Piercing Connectors(IPC)

Insulation Piercing Connectors (IPC) are used for making Tee/Tap-off/Service connectors to an

ABC Line. Insulation Piercing Connectors are designed to make a connection between the uncut main

conductor and a branch cable conductor without having to strip either cable to expose the conductor.

Instead, the tightening action of the IPC will first pierce the Insulation, and then make good electrical

contact between the main end and branch conductor while simultaneously insulating and sealing the

connection.

The standard size ranges for various applications are given below:

Requirement Main Cable Size Branch Cable Size

range range

Insulation Piercing Connectors for 16-95 sq mm 4 - 35 sq mm

phase & Street Lighting core

4.1 Marking and Embossing

The Connector shall be indelibly marked with the following information:

Name or Logo of manufacturer

Name Purchaser, Capex, GoO

Model Number

Sizes of “Max and Min” Main and Branch cables for which it is suitable.

The permanence of the marking shall be permanent.

4.2 Type Test For all accessories, the Type Test Report should be submitted from an Independent NABL Accredited Laboratory like CPRI The installation of the connectors shall be done in the laboratory following instructions provided by the manufacturer. The Test report shall include the Model Number, Applicable size Range, and GA Drawing showing the principal parts and dimensions of the connector.

The following shall constitute Type Tests for Insulation Piercing Connectors.

d) Electrical Ageing Test

e) Dielectric and Water Tightness Test

f) Mechanical Tightening Test & Shear – head behavior

g) Effect of tightening on main core

h) Effect of tightening on branch core

Climatic test in accordance with NFC20-540

Corrosion Test in accordance with NFC 33-003

4.3. Acceptance Tests

2

The Acceptance Tests & sampling plan to be conducted as per REC Spec. 83/ 2010 and as per relevant IS Specifications.

4.4 Drawings & Samples:

GA drawing and other particulars along with samples are to be submitted along with offer.

ANCHOR (DEAD END) & SUSPENSION CLAMPS

5.0 Scope This specification covers the design, manufacture, assembly, testing and supply of Accessories for

anchoring & suspending Aerial Bunched Cables rated 1100 volts and insulated with cross-linked

polyethylene and aluminum alloy bare messenger.

Description Application

For fitting onto a pole for anchoring

a) Dead end Clamp ( as per REC the end of a length of ABC, or for a Construction standard E-35) major change in direction.

SuspensionClamp (Bolted For supporting a length of ABC at an b) Type as per REC Construction intermediate pole in a length, with standard E-34) small angle of deviation.

5.1 Cable Data The standard sizes and characteristics of the phase and street lighting conductors, messenger wires shall

be as specified in REC specification 32/1984 or IS: 14255-1995.

The strength of the messenger shall be not less than the Value shown in Table 1.

Table-1

Conductor Size Messenger Rating

(mm2.) (as per IS 14255)

35 9.8 KN

70 17.5 KN

5.2. Marking / Embossing Anchoring Clamp, Suspension clamp should bear e) Manufacturers trade mark and logo f) Purchaser, Capex, GoO

c) Product Code or Reference d) Traceability Code/Batch Number

5.3. Type Test For Dead End & Suspension clamps, the Type Test Report s should be submitted from an Independent NABL Accredited Laboratory / CPRI as per REC Spec-84/2010.

5.4 Acceptance Tests

The Acceptance Tests & sampling plan to be conducted as per REC Spec. 84/ 2010. & as per relevant IS Specifications..



6.0 EYE HOOKS

e) Eye hooks shall be as per REC construction standard E-35 (Type – A)

f) It should be made of forged hot dip galvanized steel as per IS-1570

g) The clamp corrosion resistance should conform to standards IS 2629 & IS 2633.

h) Minimum breaking Load should be 20 KN.

6.1 Type Test For Eye hooks, the Type Test Report s should be submitted from an Independent NABL Accredited Laboratory / CPRI as REC Spec-32/1984 & 84/2010 and as per relevant IS Specifications.


The Acceptance Tests & sampling plan to be conducted as per REC Spec. 32/ 1984. & 84/2010 and as per relevant IS Specifications.



7.0 NEUTRAL CONNECTOR

b The Neutral Connector shall be as per REC Construction standard E-36 c It should be consist of corrosion resistant extruded Aluminum Alloy body suitable for

messenger wire as mentioned under clause-3 above.

7.1 Type Test For Eye hooks, the Type Test Report s should be submitted from an Independent NABL Accredited Laboratory / CPRI as REC Spec-32/1984 & 84/2010 and as per relevant IS Specifications.

.


The Acceptance Tests & sampling plan to be conducted as per REC Spec. 32/ 1984. & 84/2010 and as per relevant IS Specifications.



GUARANTEED TECHNICAL PARTICULARS FOR INSULATION PIERSING CONNECTOR

Sl. No.

Description Guaranteed particulars to be submitted by the

Vendors along with offer

1 Name and address of the

Manufacturer

Is Manufacturer of accessories

as ISO 9001-2000

2 a) Copies of certificate enclosed b) Are GA drawing enclosed

c) Are Samples are submitted

3 Applicable standard

4 Type of connectors

5 Application

Is any metallic part carrying 6 potential in operation exposed

during installation

Are end caps of branch cable 7 a) Slide on type

b) Rigid type

8 Are torque limiting shear head

provided to tightening bolts

Range of cable sizes 9 accommodated for main and

branch

10 Min and Max torque defined

Torque for establishing 11 connection between main and

branch

12 Material used for teeth

13 Surface finish of teeth

Maximum tensile load for no

14 breakdown of main conductor(cross section)

15 Max. tensile load on branch

conductor for no break/slippage

16 Voltage withstand under water

emersion

17 No. of cycles

m) Max temp at each cycle n) Marking and embossing on the

connector

GUARANTEED TECHNICAL PARTICULARS FOR SUSPENSION CLAMP FOR BARE MESSENGER WIRE

Sl. No. Description Guaranteed particulars to be submitted by

the Vendors along with offer

1 Name and address of the manufacturer


3 Type of clamp

4 Type of design

5 Voltage Grade(kV)

6 Loop anchor attachment(open/close)

7 Installation (with/without dis-assembly)

8 Type & grade (metallic/non-metallic

material)

9 Type of hot dip galvanizing & thickness

of Zinc coating

10 Marking

11 Colour of non-metallic parts

12 Dimensions

13 Approximate weight

14 Minimum Breaking Load (KN)

15 Maximum allowable load(KN)

16 Max. angle of deviation of conductor

(degrees)

17 Method of casting

18 Are GA drawing & samples enclosed

GUARANTEED TECHNICAL PARTICULARS FOR DEAD END CLAMP FOR BARE MESSENGER WIRE (To be submitted along with offer)

Sl.. Description Guaranteed particulars to be submitted by

the Vendors



3 Type of clamp

4 Type of design

5 Voltage Grade(kV)

6 Loop anchor attachment(open/close)

7 Installation (with/without dis-assembly)

8 Type & grade (metallic/non-metallic

material)

9 Type of hot dip galvanizing & thickness

of Zinc coating

10 Marking

11 Colour of non-metallic parts

12 Dimensions


14 Ultimate tensile strength(KN)


16 Slip Strength (KN)


18 Operating temperature (deg.cent)

a) Continuous Operation

b) Short circuit condition

19 Are GA drawing & samples enclosed

GUARANTEED TECHNICAL PARTICULARS FOR NEUTRAL CONNECTOR FOR

BARE MESSENGER WIRE

Sl. No. Description Guaranteed particulars to be submitted by

the Vendors



3 Type of clamp

4 Type of design

5 Voltage Grade(kV)

6 Dimensions


8 Minimum Breaking Load (KN)



Are GA drawing & samples enclosed

11

Guaranteed Technical Particulars of Eye Hook

Guaranteed Technical

Sl. No. Description Particulars submitted by

Vendors

1 Name and Address of the Manufacturer

2 Type of Hooks

3 Maximum weight span for 4x95's

Maximum weight span for 4x50's

4 Horizontal pull out load

5 Types of Facades for which it is suitable

6 Stand off from Façade

7 Method of fixing to Façade

8 Installation(with/without disassembly)

9 Type and grade of Metallic Material

10 Type of Hot Dip Galvanizing Thickness of Zinc

Coating

11 Markings:- As specified in IEC – 947

12 Dimensions

13 Net Weight

14 Ultimate tensile strength

15 Acceptance tests

MILD STEEL CHANNEL & ANGLE

Clause

No. TECHNICAL SPECIFICATIONS OF MILD STEEL CHANNEL & ANGLE

1.00.00 SCOPE

This specification covers design, manufacture, testing and dispatch to owner‟s stores of M.S. Channel & Angle for use in structures in distribution system.

2.00.00 APPLICABLE STANDARD

Materials shall conform to the latest applicable Indian standards. In case bidders offer steel section and supports conforming to any other international specifications which shall be equivalent or better than IS, the same is also acceptable.

Sl.No. Standard No. Title 1 IS: 2062 Grade „A‟ Quality Specification for M.S.Angles,

M.S.Channel 2 IS: 2062 Chemical and Physical composition of material 3 IS: 1852 Rolling and Cutting Tolerances for Hot Rolled Steel products

3.00.00 GENERAL REQUIREMENTS

3.01.00 Raw material

The Steel Sections shall be re-rolled from the BILLETS/INGOTS of tested quality as per latest version of IS:2830 or to any equivalent International Standard and shall be arranged by the bidder from their own sources. The Chemical composition and Physical properties of the finished material shall be as per the equivalent standards. Chemical Composition and Physical Properties of M.S. Angles, M.S. Channels, and M.S.Flat conforming to

IS: Conforming to IS:2062/84

3.02.00 Chemical Composition

3.03.00 Chemical composition For Fe 410 WA Grade 1 C - 0.23% MAX

2 Mn - 1.5% MAX

3 S - 0.050% MAX

4 P - 0.050% MAX

5 SI - 0.40% MAX6 CE

(Carbon Equivalent)- 0.42% MAX

3.04.00 Mechanical Properties

1. Tensile strength Kgf/mm²‾ - 410 2. Yield stress Min. for thickness/diameter < 20 mm - 26 Kgf/mm² OR 250 N/ mm² 20-40 mm - 24 Kgf/mm² OR 240 N/ mm² > 40 mm - 23 Kgf/mm² OR 230 N/ mm² 3. Elongation % - 23% 4. Bend Test (Internal Dia) - Min-3ţ (t–is the thickness of the material). 3.05.00 Tolerance

Variation in ordered quantity for any destination and overall ordered quantity be only to the extent of ±2%.

Rolling and weight tolerances shall be as per version of IS: 1852 or to any equivalent International Standard.

4.00.00 TEST

Steel Section shall be tested in IS approved Laboratory or Standard

Laboratory the Bidder country having all facilities available for conducting all the test prescribed in relevant IS or IEC or to any equivalent International

Standard or any recognized and reputable International Laboratory or Institutions.

The bidders are required to specifically indicate that;

They hold valid IS (or equivalent IEC) License. Steel Section offered are bearing requisite IS certification or equivalent marks.

The bidders are required to submit a copy of the valid IS (or equivalent IEC) License clearly indicating size and range of product against respective ISS or any equivalent International Standards along with their offer.

MARKING

5.00.00 It is desirable that the bidder should put his identification marks on the finished material. The mark shall be in “legible English letter” given with marking dies of minimum 18 mm size.

6.00.00 INSPECTION AND TEST CERTIFICATES The material to be supplied will be subject to inspection and approval by the purchaser‟s representative before dispatch and/or on arrival at the destination. Inspection before dispatch shall not however, relieve the bidder of his responsibility to supply the Steel Sections strictly in accordance with the specification. The purchaser‟s representative shall be entitled at all reasonable time during manufacture to inspect, examine and test at the bidder‟s premises the materials and workmanship of the steel section to be supplied. As soon as the steel Section are ready for testing, the bidder shall intimate the purchaser well in advance , so that action may be taken for getting the material inspected. The material shall not be dispatched unless waiver of inspection is obtained or inspected by the purchaser‟s authorized representative. Test certificates shall be in accordance with latest version of the relevant Indian Standards or any equivalent International Standard. The acceptance of any batch/lot shall in no way relieve the bidder of any of his responsibilities for meeting all the requirements of the specification and shall not prevent subsequent rejection of any item if the same is later found defective.

TECHNICAL SPECIFICATION OF INSULATORS

1. GENERAL:

This specification covers the design, manufacturing, testing, supply, delivery and performance

requirements of different types of insulators indicated in our Schedule of requirements for use in

the distribution network of SOUTHCO.

The insulators shall conform in all respects to highest standards of engineering, design,

workmanship, this specification and the latest revisions of relevant standards at the time of offer

and the Purchaser shall have the power to reject any work or material, which, in his judgment is

not in full accordance therewith.

2. SERVICE CONDITIONS:

Equipment to be supplied against the specification shall be suitable for satisfactory continuous

operation under the following tropical conditions.

a) Maximum ambient air temperature 50 ˚ C

b) Maximum daily average air temperature 40 ˚ C

c) Maximum yearly average ambient air temperature 32 ˚ C

d) Maximum temperature attainably by a body

e) Exposed to the Sum. 60 ˚ C

f) Minimum ambient air temperature -5 ˚ C

g) Maximum relative humidity 100%

h) Minimum number of rainy days per annum 70

i) Average number of rainy days per annum 120

j) Average annual rain fall 150cm.

k) Number of months of tropical monsoon conditions 4

l) Maximum wind pressure 260Kg./m2

m) Degree of exposure to atmospheric pollution normally

n) Atmosphere. Polluted.

Environmentally, the region where the work will take place includes coastal areas, subject to high relative humidity, which can give rise to condensation. Onshore winds will frequently be salt laden. On occasions, the combination of salt and condensation may create pollution conditions for outdoor materials. Therefore, outdoor material shall be designed and protected for use in exposed, heavily polluted salty corrosive and humid coastal atmosphere.

3. APPLICABLE STANDARDS:

Unless otherwise it is stipulated in this specification, the insulators shall comply with Indian standard

specification IS: 731-1971 and the insulator fittings with IS 2486(Part-I)-1971 and IS: 2486(Part-II)-

1974 or the latest version thereof.

The Bidder may propose alternative standards, provided it is demonstrated that they give a degree of quality

and performance equivalent to or better than the referenced standards. The purchaser shall adjudge whether

to accept or reject any standards. The Bidder shall furnish a copy of the alternative standard proposed along

with his bid. If the alternative standard is in a language other than English, an English translation shall be

submitted with the standard. In case of conflict the order of the precedence shall be (1) IEC or ISO standards,

(2) Indian Standards, (3) Other alternative standards. This list is not to be considered exhaustive and

reference to a particular standard or recommendation in this specification does not relieve the Contractor or

the necessity of providing the goods complying with other relevant standards or recommendation.

The insulators shall be of porcelain. These shall be non-absorbent and vitreous throughout. The

exposed surface shall be glazed. Unless otherwise it is specified, the glaze is of brown 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. The insulators shall have adequate

mechanical strength, high degree of resistance to electrical puncture, resistance to climatic &

atmospheric conditions prevailing at site and made from one piece of moulded porcelain.

B. TECHNICAL SPECIFICATIONS OF 11 KV PIN INSULATOR

1.0 11 Kv Pin Insulators: - IS-731/77 (Porcelain Insulator for O/H power lines with nominal

voltage greater than 1000 volts.

2.0 Design and Construction

The material shall conform in all respect to the relevant Indian standards with latest amendments indicated below.

Indian Standards Title

BIS:731/1976 Porcelain insulators for overhead power lines with a nominal voltage greater than 1000V

BIS:2486 (Part-1 to Part-4) Metal fittings of insulators for overhead power lines with nominal voltage greater than 1000V

BIS:7935-1975 Porcelain insulators for overhead power lines with a nominal voltage upto and including 1000V

REC SPEC : 3/1971 11 KV Porcelain insulators and fittings

REC SPEC : 21/1981 Guy Insulator (Stay Insulator) 3.0 General Requirements for 11 KV Pin Insulators

All insulators for 11KV shall conform to Type B of latest version of IS: 731. Insulator shall be as per enclosed drawing. Pin insulator shall consist of a single piece of porcelain, intended to be mounted rigidly on supporting structure by a pin, which passes up inside the insulator. The pin type insulator shall have a top groove and shall be threaded to take mild steel pins. The profile of threads shall be as per IS: 1445.

Insulators shall confirm the following specific conditions of I.S. given below

Insulator Designation Minimum Mechanical

Failing Load Minimum Creepage

Distance

11KV Pin Insulator Type B of IS:731 10KN 320mm

Tests:

The insulators shall comply with the following tests as per IS: 731-1971.

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.

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.

Routine Test

a) Visual examination.

b) Mechanical routine test(for string insulator units only) and

c) Electrical routine test(for string insulator units only)

Marking

Each Insulator shall be legibly and indelibly marked to show the following.

a) Name and trade mark of the manufacturer.

b) Month and year of manufacture

c) Minimum failing load in Newtons

d) Country of the manufacturer and

e) ISI Certification mark,if any. f) Specific Parameters & Layout Conditions.

4.4.2 Marking on porcelain shall be printed and shall be applied before firing.

4.5 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.

TECHNICAL SPECIFICATION OF 11KV G.I.PIN

11 KV GI Pin: - Confirming to IS-2486 Part-I/1971.

a) The pins shall be of single piece obtained by the process of forging. They will not be made by any process using more than one piece of material. The pin will have 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. All ferrous pins, nuts and washers, except those made of stainless steel shall be galvanized by hot dip process. Other fittings, i.e flat washers and spring washers may be electro-galvanized as per IS: 2486. The threads of nuts, and toped holes, when cut after galvanization shall be well oiled or greased.

b) The pins shall be as per relevant figure indicated in IS 2486 (part II) having stalk length of 165 mm and shank length of 150 mm with minimum failing load of 10 KN with large heads and shall match with the pin type insulators with cemented zinc thimble having similar threads.

1.0 TESTS:

The pins shall be tested as per IS: 2486 (part-1):1993 Type Test:

The bidder has to enclose the reports of the following type tests carried out in any govt. recognized laboratory along with the bid documents.

a) Checking of Threads on Heads b) Galvanizing Test c) Visual Examination d) Mechanical Test.

Acceptance Tests:

Following tests shall be carried out at the works of the manufacturer before dispatch.

a) Checking of Threads on Heads

b) Galvanizing Test

c) Visual Examination

d) Mechanical Test.

Lightning Arrestor

TECHNICAL SPECIFICATION OF 11 KV LIGHTNING ARRESTOR

(VOLTAGE CLASS SURGE ARRESTORS)

The specification covers the design, manufacture, shop & laboratory testing before despatch, supply of 11

KV, Station class heavy duty, gapless metal oxide Surge Arrestors, insulating base, clamps, complete fittings

& accessories suitable for feeders including arrester's electrode earthing.

1.0 STANDARDS

The design, manufacture and performance of Surge Arrestors shall comply with IS: 3070 Part-3 and other

specific requirement stipulated in the specification Unless otherwise, specified, the equipment, material and

processes shall conform to the latest applicable Indian/International Standards as listed hereunder:

IS: 2071-1993 (Part-1): Methods of High Voltage Testing General Definitions &Test

IS: 2071-1974 (Part-2): Test Procedures

IS: 2633-1986 : Methods for Testing uniformity of zinc coated Articles.

IS: 3070-1993 (Part-3): Specification for surge arrestor for alternating current

IS:4759-1996 : Specification for hot dip zinc coating on Structural Steel

IS: 5621-1980: Hollow Insulators for use in Electrical Equipment.

IS: 6209-1982: Methods of Partial discharge measurement.

IS: 6745-1980: Methods for determination of mass of zinc coating on

IEC:TC-37 : Test Procedures.

ANSI/IEEE-C.62.11 (1982): Metal Oxide, Surge Arrestor for A.C. Power Circuits.

IEE-99-4: Surge Arrestors.

The equipment complying with any other internationally accepted standards shall also be considered if it

ensures performance equivalent to or superior to the India Standards.

2.0 GENERAL REQUIREMENT

2.1 The Metal Oxide gap less Surge Arrestor without any series or shunt gap shall be suitable for protection

of UG cable, associated equipment from voltage surges resulting from natural disturbance like lightening as

well as system disturbances.

2.2 The surge arrestor shall draw negligible current at operating voltage and at the same time offer least

resistance during the flow of surge current.

2.3 The surge arrestor shall consist of non-linear resistor elements placed in series and housed in electrical

grade porcelain housing/silicon polymeric of specified creepage distance.

2.4 The assembly shall be hermetically sealed with suitable rubber gaskets with effective sealing system

arrangement to prevent ingress of moisture.

2.5 The surge arrestor shall be provided with line suitable for cable for vertical and horizontal take off. The

earth terminals shall be provided of suitable size. The groundside terminal of surge arrestor shall be

connected with 50x6mm- galvanized strip, one end connected to the surge arrestor and second end to a

separate ground electrode (Electrode type of earthing). The contractor shall also recommend the procedure

which shall be followed in providing the ear thing/system to the Surge Arrestor.

2.6 The surge arrestor shall not operate under power frequency and temporary over voltage conditions but

under surge conditions, the surge arrestor shall change over to the conducting mode.

2.7 Surge arrestor shall have a suitable pressure relief system to avoid damage to the porcelain/silicon

polymeric housing and providing path for flow of rated fault currents in the event of arrestor failure.

2.8 The reference current of the arrestor shall be high enough to eliminate the influence of grading and stray

capacitance on the measured reference voltage.

2.9 The surge arrestor shall be thermally stable and the contractor shall furnish a copy of thermal stability test

with the bid.

2.10 The arrestors for 11 KV system shall be suitable for mounting on transformers as well as in the yard.

The supplier shall furnish the drawing indicating the dimensions, weight etc. of the surge arrestors for the

design of mounting brackets.

2.11 The arrestor shall be capable of handling terminal energy for high surges, external pollution and

transient over voltage and have low losses at operating voltage.

3.0 ARRESTOR HOUSING

3.1 The arrestor housing shall be made up of porcelain/silicon polymeric housing and shall be homogenous,

free from laminations, cavities and other flaws of imperfections that might affect the mechanical and

dielectric quality. The housing shall be uniform brown colour, free from blisters, burrs and other similar

defects. Arrestors shall be complete with insulating cases, fasteners for stacking units together and terminal

connectors.

3.2 The housing shall be so coordinated that external flashover shall not occur due to application of any

impulse or switching surge voltage upto the maximum design value for arrestor. The arrestors shall not fail

due to contamination. The 11KV arrestors housing shall be designed for pressure relief class as given in

Technical Parameters of the specification.

3.3 Sealed housing shall exhibit no measurable leakage.

4.0 TESTS

4.1 Test on Surge Arrestors

The Surge Arrestors offered shall be type tested not earlier than 5 years before the date of opening of this

tender. The surge arrestors shall be subjected to routine and acceptance tests in accordance with IS:

3070(Part3)-1993. In addition, the suitability of the Surge Arrestors shall also be established for the

following:

* Residual voltage test

* Reference voltage test

* Leakage current at M.C.O.V.

* P.D. Test

* Sealing test

* Thermal stability test

* Aging and Energy capability test

* Watt loss test

Each metal oxide block shall be tested for guaranteed specific energy capability in addition to

routine/acceptance test as per IEC/IS.

4.2 The maximum residual voltages corresponding to nominal discharge current of 10KA for steep current,

impulse residual voltage test, lightning impulse protection level and switching impulse level shall generally

conform to Annexure-K of IEC-99-4.

4.3 The bidder shall furnish the copies of the type tests and the characteristics curves between the residual

voltage and nominal discharge current of the offered surge arrestor and power frequency voltage V/s time

characteristic of the surge arrestor subsequent to impulse energy consumption as per clause 6.6 of IS: 3070

(Part-3) offered along with the bid.

4.4 The surge arrestors housing shall also be type tested and shall be subjected to routine and acceptance tests

in accordance with IS: 2071.

4.5 Galvanization Test

All Ferrous parts exposed to atmospheric condition shall have passed the type test and be subjected to routine

and acceptance test in accordance with IS: 2633 & IS: 6745.

5.0 NAME PLATE

5.1 The nameplate attached to the arrestors shall carry the following information: -

* Manufacturing Trade Mark

* Year of Manufacture

* Rated Voltage

* Continuous Operation Voltage

* Pressure relief rated current

* Name of Client-

* Purchase Order Number along with date.

6.0 INSPECTION

6.1 All tests and inspection shall be made in the manufacturer‟s works unless otherwise specifically agreed

upon by the manufacturer and purchaser at the time of placement of purchase order. The manufacturer shall

afford to the inspector representing the purchaser, al reasonable facilities, without charge to satisfy him that

the material being furnished is in accordance with these specifications. The purchaser reserves the right to get

an component/material being used by the manufacturer of the Surge Arrestor tested from any recognized test

house.

6.2 The inspection by the purchaser or his authorized representative shall not relieve the contractor of his

obligation of furnishing equipment in accordance with the specifications.

7.0 DRAWING AND INSTRUCTION MANUALS

Within 15 days of receipt of the order, the successful tenderer shall furnish to the purchaser the following

drawings and literature for approval:

a. Outline dimensional drawings of Surge Arrestor and all accessories.

b.Assembly drawings and weights of main component parts.

c. Instructions manual

d. Drawing showing details of pressure relief value

e. Volt-time characteristics of surge arrestors.

f. Detailed dimensional drawing of porcelain housing/ Silicon polymeric i.e. internal diameter, external

diameter, thickness, height profile creepage distance, dry arching distance etc.

GURANTEED TECHNICALPARTICULARSFOR

11KVLIGHTNINGARRESTOR

(To be submitted along with offer)

TECHNICAL & GUARANTEED - PARTICULARS.

12 KV 5 KA Distribution Class L.A.

Sr No.

Particulars

Requirement

To be

Specified by

the bidder

1. Type

2. Model

3. No.of Units

4. Rated voltage (KV) RMS. 12

5. Nominal Discharge current ( K Amps.) 5

6. Discharge Class Distribution

Class.

7. Reference Current ( MA) 1

8. Reference voltate (KV) > rated voltage

9. Current at MCOV.

i) Resistive current IR (Micro Amps) < 0.3 MA.

ii)Capacitive current IC ( - do-) About 1.0 MA

10. Protective ratio. 1.78

11. Maximum residual voltage for discharge

Current of 8/ 20 micro sec. Wave at.

i) 0.5 time the nominal discharge current(KV Peak) 40

ii) 1 time -do-(KV rms) 42

iii)2 times -do-(KV rms) 48

12 Maximum continous operative voltage (KV rms) 12

13 High Current impulse withstand(KA) 65

14 Energy dissipation capability (KJ/KV)

15 Insulation withstand.

i) Lightening Impulse (KV Peak) 75

ii)P.F. Dry/ Wet (KV rms) 28

16 Temporary over voltage withstand

Capability (KV Peak)

i) At 0.1 second 19

ii) At 2 Seconds 17.5

iii) At 10 Seconds 15.5

iv)At 100 Seconds 14

17 Maximum radio interference voltage PD=Less than

50 PC.

(KV rms) / partial discharge.

18 Maximum step current impulse 40

Residential voltage at nominal

Discharge current of 1 micro sec.front time(KV Peak).

19 Maximum switching impulse residual

Voltage at 50 x 100 micro sec.wave at 500 Amp.

(KV Peak)

20 Height of complete unit (mm) 250 + 15

21 Maximum recommended spacing between

Arrestor centre to centre(mm) 450

22 Clearance required from ground equipment

To various heights of arrestor unit(mm)

23 Earthign arrangement. To be

provided

24 Mounting falange dimensional details (mm) As per your

sketch.

25 Total crrepage distance (mm) 360

26 Weight of complete unit(kg.) 3.2 (Approx.)

Signature of Bidder

(This form is to be duly filled up by the bidder & submit along with the Tender)

TECHNICAL SPECIFICATION OF EARTHING COIL:

1. Qualification Criteria of Manufacturer:-

The prospective bidder may source Earthing Coil from manufacturers who must qualify all the following

requirements :

a) The manufacturer must have successfully carried out Type Test of similar item from any NABL

Accredited Laboratory within the last 5 years, prior to the date of submission of the bid.

b) The manufacturer should have supplied at least 1000 nos. to electricity supply utilities / PSUs. The bidder

should enclose Performance Certificates from the above users issued in the name of the manufacturer as

proof of successful operation in field.

2. SCOPE

The specification covers design, manufacture, testing for use in earthing of the HT poles.

3. GENERAL REQUIREMENTS

Earthing coils shall be fabricated from soft GI Wire Hot Dip Galvanized. The Hot Dip galvanized wire shall

have clean surface and shall be free from paint enamel or any other poor conducting material. The coil shall

be made as per REC constructions standard.

The Hot Dip galvanizing shall conform to IS: 2629/1966, 2633/1972 and 4826/1969 with latest amendments.

4. TESTS

Galvanizing Tests

Minimum Mass of Zinc

On GI Wire used 280 cm/m²

After Coiling-266 gm/m².The certificate from recognized laboratory shall be submitted towards mass of zinc.

Dip Test

Dip test shall stand 3 dips of 1 minute and one dip of ½ minute before coiling and 4 dips of 1 minute after

coiling as per IS: 4826/1979.

Adhesion Test

As per ISS 4826 – 1979.

5. DIMENSIONAL REQUIREMENT

Nominal dia of GI Wire -4 mm (Tolerance±2.5%)

Minimum no. of turns – 115 Nos.

External dia of Coil (Min) – 50 mm

Length of Coil (Min) – 460 mm

Free length of GI Wire at one end coil (Min.) – 2500 mm

Minimum length of wire to be grounded during installation -1000 mm.

The turns should be closely bound. Weight of one finished Earthing Coils (min.) –1.850 Kg.

EARHTING COIL

GUARANTEED TECHNICAL PARTICULARS

(To be submitted along with Offer) Sl.No. GENERAL TECHNICAL PARTICULARS BidderOffer


2 No. of turns

3 External dia of Coil

4 Length of Coil

5 Mass of Zinc

6 Total weight of Coil

7 Whether drawing enclosed (yes)

BIDDER’S SIGNATURE WITH SEAL

(This form is to be duly filled up by the bidder & submit along with the Tender)

TECHNICAL SPECIFICATION OF 11 KV ‘V’ CROSS ARM, BACK CLAMP FOR ‘V’ CROSS

ARM:

Qualification Criteria of Manufacturer:-

The prospective bidder may source the above items from manufacturers who must qualify the following

requirements:

The manufacturer should have supplied at least 1000 no‟s (of each item) to electricity supply utilities / PSUs.

The bidder should enclose Performance Certificates from the above users issued in the name of the

manufacturer as proof of successful operation in field.

(a) Cross arms and Pole Top Brackets for 11 KV constructions at intermediate and light angle pole shall

be fabricated from grade 43A mild steel of channel section and for heavy angle poles, end poles and

section poles fabricated from grade 43A mild steel of angle section. The grades of structural steel

shall conform to IS – 226: 1975.

1. V cross arm shall be made of 75X40X6 mm MS channel for 11KV.

2. The cross arm should be hot dipped galvanized generally conformity to IS2633.72.

3. The Cross arm should be welded & jointed at any place except as specified.

4. The clamp for the cross arm shall be of GI & shall be hot dipped galvanised generally conformity to

IS2633.72.

5. The clamp should be designed to fit for the specified poles. The Back Clamp for 11 KV shall be made out

of 75 x 10 MS Flat and shall be suitably designed to fit RS Joist Pole11 Mtr long (150X150).

b)The Pole Top Bracket (F Clamp) shall be made out of 75 x 10 MS Flat suitably designed to fit RS Joist

Pole 11 Mtr long (150X150) for 11 KV.

Except where otherwise indicated all dimensions are subject to the following tolerances: Dimensions up to

and including 50mm:+1mm: and dimensions greater than 50mm:+2%

All steel members and other parts of fabricated material as delivered shall be free of warps, local

deformation, unauthorized splices, or unauthorized bends. Bending of flat strap shall be carried out cold.

Straightening shall be carried out by pressure and not by hammering.

Straightness is of particular importance if the alignment of bolt holes along a member is referred to its edges.

Holes and other provisions for field assembly shall be properly marked and cross referenced. Where required,

either by notations on the drawing or by the necessity of proper identification and fittings for field assembly,

the connection shall be match marked. A tolerance of not more than 1mm shall be permitted in the distance

between the center lines of bolt holes.

The holes may be either drilled or punched and, unless otherwise stated, shall be not more than 2mm greater

in diameter than the bolts. When assembling the components force may be used to bring the bolt holes

together (provided neither members nor holes are thereby distorted) but all force must be removed before the

bolt is inserted. Otherwise strain shall be deemed to be present and the structure may be rejected even though

it may be, in all other respects, in conformity with the specification.

The back of the inner angle irons of lap joints shall be chamfered and the ends of the members cut where

necessary and such other measures taken as will ensure that all members can be bolted together without strain

or distortion. In particular, steps shall be taken to relieve stress in cold worked steel so as to prevent the onset

of embitterment during galvanizing. Similar parts shall be interchangeable.

Shapes and plates shall be fabricated and assembled in the shop to the greatest extent practicable. Shearing

flame cutting and chipping shall be done carefully, neatly and accurately. Holes shall be cut, drilled or

punched at right angles to the surface and shall not be made or enlarged by burning. Holes shall be clean-cut

without torn or ragged edges, and burrs resulting from drilling or reaming operations shall be removed with

the proper tool.

Shapes and plates shall be fabricated to the tolerance that will permit field erection within tolerance, except

as otherwise specified. All fabrication shall be carried out in a neat and workmanlike manner so as to

facilitate cleaning, painting, galvanizing and inspection and to avoid areas in which water and other matter

can lodge. Contact surfaces at all connections shall be free of loose scale, dirt, burrs, oil and other foreign

materials that might prevent solid seating of the parts.

Shape & size

1. Cross arm shall have 2 holes of 22mm dia for 11KV for fixing of insulator. The center-center

distance between holes shall be 1070mm for 11KV & holes shall be in the middle of the top width

of cross arm.

Fixing of Cross Arms

After the erection of supports and providing guys, the cross-arms are to be mounted on the support with

necessary clamps, bolts and nuts. The practice of fixing the cross arms before the pole erection should be

followed.

GUARANTEED TECHNICAL PARTICULARS 11 KV V-CROSS ARM

Sl.No. Description Unit Bidder’s offer

1 Type of cross arm

2 Grade of steel

3 Steel standard

4 Dimensions

5 Working load(Kg)

6 Steel tensile strength (N/m²)

7 Weight of cross arm

8 Whether drawing has been submitted

with the bid

GUARANTEED TECHNICAL PARTICULARS BACK CLAMP FOR ‘V’ CROSS ARM

Sl.No. Description Unit Bidder’s offer

1 Type of cross arm

2 Grade of steel

3 Steel standard

4 Dimensions

5 Working load(Kg)

6 Steel tensile strength (N/m²)

7 Weight of cross arm

8 Whether drawing has been submitted with the bid

GUARANTEED TECHNICAL PARTICULARS FOR F-CLAMP

SL No

Name of the Particulars Desired

Bidder’s Offer Value

1 Type of crossarm

2 Grade of steel

3 Steel standard

4 Fabrication Standard

5 Dimensions Mm

6 Steel section utilized

7 Steel tensile strength N/cm2

8 Working load Kg

Details of galvanizing method utilized a n d

9 s t a n d a r d / s p e c i f i c a t i o n conforming

TECHNICAL SPECIFICATION FOR 11 KV 45 KN DISC

INSULATORS

6. SCOPE :

This specification covers the manufacture, testing and works supply and delivery of 11 KV Disc

insulators. The Porcelain insulators shall conform to IS:731-1971ammended upto date.

Insulators shall be of Tongue & Clevis type (T&C).Disc insulators made of glazed porcelain

shall be used as insulators on dead ends or on suspension type lines of 11 KV and above.

Tongue & Clevis type (T & C) disc insulators of mechanical strength not less than 45KN shall

be used confirming to IS: 731/1971. These shall be mounted on metallic cross-arms with the

help of suitable non-magnetic galvanised iron hardware fittings. Small fittings like spring

washers, nuts etc may be electro-galvanised.

7. SERVICE CONDITIONS :

The insulators to be supplied against this specification shall be suitable for

satisfactory continuous operation under the following tropical conditions.

2.1.1 Maximum ambient temperature (Degree C) … 50

2.1.2 Minimum ambient temperature (Degree C) … 3.5

2.1.3 Relative Humidity (%) … 10 to 100

2.1.4 Maximum Annual Rainfall (mm) … 1450

2.1.5. Maximum Wind pressure (kg/m.sq.) … 150

2.1.6 Maximum wind velocity (km/hour) … 45

2.1.7 Maximum altitude above mean sea level (meter) … 1000

2.1.8 Isoceraunic level (days/year) … 50

2.1.9 Seismic level (Horizontal acceleration) … 0.3 g

2.1.10 Moderately hot and humid tropical climate

conductive to rust and fungus growth

3. System Particulars :

a) Nominal System Voltage 11 KV

b) Corresponding highest system Voltage 12 KV

c) Frequency 50 Hz with 3% tolerance

d) Number of phase 3

e) Neutral earthing effectively grounded.

f) Min. Impulse withstand voltage 75 KV

18. Standards :

Unless otherwise specified elsewhere in the specifications insulators shall confirm to the

latest revisions of all relevant standards .

(a) General Requirements

to?

10 Weight of cross arm kg

11 Whether drawing has been submitted with the bid

The Porcelain insulators shall generally conform to IS:731-1971 and any amendments up

to date to the same .

21. Conductors :

The Disc Insulators will be used on lines on which the conductors will be A.A.A.

Conductor of size up to 100 sq. mm. The insulators should withstand the conductor

tension, the reversible wind load as well as the high frequency vibrations due to wind.

a) Type

1. Insulator shall be suitable for both the suspension and strain type of load & shall be of

Tongue and Clevis type. The insulators shall conform to Type „B‟ of IS:731-1971.

2. Diameter of porcelain disc insulator shall be 255mm . The center to center distance

between Tongue and Clevis shall be 145mm.

3. Insulator Ends.

Disc Insulators shall have Tongue and Cleave ends. The security clips will have to be

provided as per fig. 25 of I.S. 2486 (Part-2) 1989 ( amended up to date) REC Specification

3/1971(Revised 1993).

1. The colour of the units shall be brown for 45 KN Disc Insulators .

2. The number of units to be used both on suspension and tension strings shall be as given below

:

Voltage Class Suspension Strings Tension Strings.

Single Double Single Double

33 3 3x2 3 3x2

22 2 2x2 2 2x2

11 1 1x2 1 1x2

iv). Electromechanical & Mechanical Strength :

The mechanical and electromechanical strength of the individual and the complete Disc

shall be 45 KN.

22. Creepage Distances :

The minimum creepage distance for each 11KV disc Insulator shall 320mm.

6.0 Tests : Suitable number of individual units and complete string shall be subject to the

following tests in accordance with IS:731/1971 with its latest amendments.

24. Type Tests :

Following Type test shall be carried out on porcelain insulators as specified in IS: /971 amended up to date.

Visual Examination. Verification of dimensions. Visible Discharge Test.

Impulse voltage withstand test.

Impulse voltage flashover test. Wet one Minute Power Frequency withstand test and West Flashover test.

Temperature Cycle test. Electromechanical failing load test.

Power frequency puncture withstand test. Porosity test. Galvanizing test.

12. Acceptance Tests :

The test samples after having withstood the routine test shall be subject to

the following acceptance tests in order indicated below:

Verification of dimensions. Temperature Cycle test.

Twenty four hour mechanical test.

Electromechanical failing load test.

Power Frequency puncture withstand test. Porosity test.

Galvanizing test.

18. Routine Tests:

1.Visual Examination

2. Mechanical test

3. Electrical test

4. Twenty four hours mechanical test

5. Electro mechanical failing load test

7 Test Certificate :

The tenderer shall furnish detailed type test reports of the offered Disc Insulators as per

clause 6.1 of the Technical Specifications at the NABL approved laboratories to prove that

the Disc Insulators offered meet the requirements of the specification. These Type Tests

should have been carried out within five years prior to the date of opening of this tender.

i) Their offered Disc Insulators are already fully type tested at approved Laboratory

CPRI/NABL within five years prior to the date of opening of this tender.

ii) There is no change in the design of type tested Disc Insulators and those

offers against this tender.

iii) Such tenderers complying (i) and (ii) above shall furnish an undertaking in the

format schedule.

The purchaser reserves right to demand repetition of some or all the Type Test 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. However, such unit rates will not be

considered for evaluation of the offer. In case the unit fails in the Type Tests, the complete

supply shall be rejected.

8. Testing Facilities :

The tenderer must clearly indicate what testing facilities are available in the works of the

manufacturer and whether facilities are adequate to carry out all Routine & acceptance

Tests. These facilities should be available to Board's Engineers if deputed or carry out or

witness the tests in the manufacturer works. If any test cannot be carried out at the manufacturer's work, the reasons should be clearly stated in the tender. The

insulators shall be tested in accordance with the procedure detailed in IS-731/1971

amended up to date.

9. Material Quality and Workmanship :

The quality of porcelain and hardware in case of porcelain insulators and core & housing in

case of polymeric insulators shall be of the highest grade and best workmanship such as is

suitable and customary for extra high tension lines and shall conform to current IS or IEC

(only in absence of the relevant I.S.S.). The porcelain shall be sound, free from defect, thoroughly vitrified and smoothly glazed

and brown in colour.

Unless otherwise specified the glaze shall cover all exposed porcelain parts of the insulator.

Glazing shall be uniform and free from defects. Small and the

insulator glaze of a total surface less than 0.5 sq.cm. ignored.

Deviation on this account may be supported by relevant IS.

isolated defects in

will however be

10 Mechanical Design :

The design shall be such that stresses due to expansion and contraction in any part of

insulator shall not lead to deterioration.

Cement used in manufacture of the insulators shall not cause fracture due to expansion or

loosening due to contraction.

11. Drawings :

The tender shall be accompanied with the detailed drawings showing the dimensions of the individual Disc giving all the design dimensions of various component parts. The

drawing for Insulators should clearly show the method of cementing the porcelain to the

metal caps and balls. Generally it shall be as per IS.

12. Markings:

12.1 Each insulator shall be legibly and indelibly marked to show the following : a) Name or trade mark of the manufacturer. b)

Voltage Type

d) Month and year of manufacturing.

d) Electromechanical strength in KN e)

Property of NESCO.

12.2 The “W” clip shall be marked with/punched with the ball and socket sizes for which it is

meant e.g.16B,20 etc.

12.3 Marking on porcelain shall be printed and shall be applied before firing.

13 Packing :

All insulators shall be packed in crates or boxes suitable for rough handling. Packing

shall be marked with the strength and KV rating.

GUARANTEED TECHNICAL PARTICULARS FOR 45 KN DISC. INSULATOR ( T&C TYPE)

Sl. Particulars

Specific Bidders offer

No

Requirement

1. Name of Manufacturer. & Address To be specified by the

bidder

2. Location of type testing To be specified by

the bidder

3 Applicable standard IS-731/1971 with

latest amendment

4 Type of insulator T&C type Disc insulator

5 Nominal System Voltage 11 KV

6 Highest System voltage 12 KV

7 Visible discharge Test voltage (Minimum) 9 KV

8 Dry Impulse withstand voltage +(1.2/50 microsecond wave) 75 KV

9 Dry Impulse flashover voltage+(1.2/50 microsecond wave) 90 KV

10. Dry 1 min. power frequency withstand Voltage kV. 60 KV

11 Wet 1 min. power frequency withstand Voltage . 35 KV

12 1 min. power frequency flashover Voltage kV. (Dry) 65 KV

13. 1 min. power frequency flashover Voltage kV.(Wet) 45KV

14 Power frequency puncture voltage 105 KV

15 Mechanical Routine test load 18 KN

16 Mechanical impact strength 45 KN

17 Shattered strengths (Glass) .. KV

18 Electromechanical Failing Load 45 KN

19 Safe working load 18 KN

20 Minimum Failing Load 45 KN

21 Creepage Distance 320 mm

22 Type and Grade of Materials :

i) Insulators Porcelain

ii) Cap Malleable Casting or S.G

iii) Pin Forged pin

iv) Locking Split pin

v) Cement Portland

23 Type of semi conducting Glaze Ceramic

24 Colour of Insulators Dark Brown

25 Weight of single disc. kg. 4 Kg(Approx.)

26 Number of Insulators per crate 4 nos./ 6 nos.

27 Cross weight of Loaded crate 20 – 30 Kg

28 Whether drawing showing dimensional details have To be enclosed by

been furnished along with bid. bidder

NB : Every insulator should bear the marking of Purchaser’s name/ Manufacturer’s name

and ISI mark.


11KV H.W fittings (T&C Type) : 11 KV Hard Ware fittings Tongue & Clevis type ,confirming to REC Construction Standard C-2 and as per

drawing.

T & C Hardware Fittings

The hardware fittings for B & S and T & C Strain Disc Insulator. For use in 33 KV and 11 KV

Overhead power lines shall comply IS:2486 (Part-I) 1971 and 2486 (Part-II) / 1974 and IS:2486 (Part-III) 1974 IS:12048 /1987 and REC Specification 24/84 or the latest revision

thereof. All Forging and Casting shall be good finish and free from flaws and other defects. The edges on

the outside of fittings such as at the Eye, Cleaves and Holes shall be rounded.

All parts of different fittings, which provide for Inter-connection shall be made such that sufficient clearance is provided at the Connection Point to ensure free movement & suspension of the Insulator string Assembly.All eye and cleaves shall be free in this manner but care shall

be taken that too much clearance between Eye & Tongs of the cleaves is avoided. All ferrous fittings and parts other than those of Stainless steel shall be hot dip

galvanized as per ISS: 2633 / 1964.Small fittings like Spring washer , Nuts etc. may be Electro- galvanized as per IS-6745 / 72.The threads of nuts and topped holes when cut after

Galvanizing shall be well cited & grassed.

Tongue & Clevics type Hardware Fittings (Conventional / ¼ Performed ) for T & C type

Strain Insulators

The Hardware fittings ( Tongue & Clevis type) shall be suitable for fixing on 75 mmx40 mm

Channel Cross Arm an accommodation 55mm²/80 mm² /100mm² Conductors. The set shall comply

of the following components :- e) Cross arms straps (Dead & Straps) with Bolt (16mm) Nut and Spring Washer.

f) Two Nos. forged cotter pints and spring washer to suit the tongue and the clevics. (iii)

Formed helical fittings should be of suitable materials i.e all alloy aluminum steel suitable

for 34mm²/55mm²/100mm² ACSR/AAAC. (iv)

Strain clamps shall be suitable for the above ACSR conductor or

AAAC.The ultimate strength of the clamp should not be less than

3000 Kg and slipping strength shall not be less than 90% of this

figure.The clamp should be malleable cast iron/All alloy A-6.

Tests : String insulator fittings shall comply with the following tests as per IS: 2486 (Part.I)

Type Tests: a) Visual examination test

i) Verification of dimensions iii) Slip

strength test d Mechanical test e Electrical resistance test vi)

Heating cycle test o) Galvanising test.

Acceptance/ Routine Test : i)Verification of dimensions ii)

Mechanical test 4. Galvanising test

5. Vidual examination test v) Routine mechanical test.

Marking : The caps and clamps shall have marked on them as trade mark & year of manufacturing.

Packing :

All hardware fittings shall be packed in bags or boxes suitable for rough handling. Packing shall be

marked with the strength and KV rating.

Guaranteed Technical Particulars :

The bidders are required to furnish the guaranteed technical particulars duly filed in the

proforma along with the bid.

v

Sl.No. Description Specified Bidders Offer

1. Manufacturer Name & To be specified by Bidder

Address

2. Standard Specification to IS: 2486 (Part-I,II &II)

which Hard ware Fittings

shall confirm.

3 Ultimate strength 3000 Kg (min)

4. Dimensions in accordance IS: 2486(Part-II)

with

5 Type of washer thickness

a) Spring 2.5 mm

b)Flat 2.5 mm

6. Type of Clamp size Tension Clamp suitable for

Squiral/Weasel/ Rabbit 7. Galvanised conform to IS 2633 , IS: 4759-1996 &

IS: 6747

8. Weight of Fittings ..

9. Tolerance in dimension if + 5%

any 10. Manufacturer trade mark to be Specified by the Bidder

embossed on the sets

11. Specific drawing to be Enclosed

enclosed. NB. All ferrous fittings and the parts other than those of stainless steel , shall be

galvanized.

Name & Signature of Bidder with seal


(For supply of LT XLPE AB Cables)

Part-1:

1.

SCOPE: This specification covers the design, manufacturing, testing, supply, delivery and performance

requirements of LV overhead ISI marked Aerial Bunched Cable (ABC) of different sizes indicated in

our Schedule of Requirements for use in the LV network of SOUTHCO

The materials offered shall have been successfully type tested and the design shall have been in

satisfactory operation for a period of not less than two years on the date of bid opening. Compliance

shall be demonstrated by submitting with the bid (i) authenticated copies of the type test reports and

(ii) performance certificates from the users.

However where the bidder offers similar but not identical material but higher size to that which has

been type tested, the difference shall be stated in Test Certificate Schedule. The purchaser shall

adjudge whether to accept or reject the offered material and type test data presented.

The scope of supply includes the provision of type tests. Rates for type tests shall be given in the

appropriate price schedule of the bidding document and shall be considered for evaluation. The

purchaser reserves the right to waive type tests as indicated in the section on Quality Assurance,

Inspection and Testing in this specification.

The Aerial Bunched Cable shall conform in all respects to highest standards of engineering, design,

workmanship, this specification and the latest revisions of relevant standards at the time of offer and

the Purchaser shall have the power to reject any work or material, which, in his judgment is not in full

accordance therewith.

2. STANDARDS:

Except where modified by this specification, the Aerial Bunched Cable shall be

designed, manufactured and tested in accordance with the latest editions of the following standards.

IES/ISO IEC: 1089 ISO: 9000

IEC: 502

Indian Standard IS: 398/1994

IS: 398(Part-4)/1994

IS: 8130/1984 IS: 10810/1984

IS:7098/1998

IS:14255/1995

Material

Round wire concentric lay

Overhead electrical

Stranded Conductors.

All Aluminum Alloy

Conductors, Quality

Management Systems.

Conductors for insulated

Electric cables.

Method of Tests for cables.

XLPE Insulated PVC.

Sheathed power cables.

Aerial Bunched Cables for

working voltage up to and

including 1100 volts.

The Bidder may propose alternative standards, provided it is demonstrated that they give a degree of

quality and performance equivalent to or better than the referenced standards. The purchaser shall

adjudge whether to accept or reject any standards.

The Bidder shall furnish a copy of the alternative standard proposed along with his

bid. If the alternative standard is in a language other than English, an English translation shall be

submitted with the standard.

In case of conflict the order of the precedence shall be (1) IEC or ISO standards, (2)

Indian Standards, (3) Other alternative standards. This list is not to be considered exhaustive and

reference to a particular standard or recommendation in this specification does not relieve the

Contractor or the necessity of providing the goods complying with other relevant standards or

recommendation.

3.0 SERVICE CONDITIONS:

The service conditions shall be as follows:

Maximum altitude above sea level Maximum ambient air temperature Maximum daily average ambient air temperature Maximum ambient air temperature Maximum temperature attainable by an object exposed to sun Maximum yearly weighted average ambient temperature Maximum relative humidity Average number of thunderstorm days per annum Average number of rainy days per annum Average annual rainfall Wind pressure as per IS:5613(Part-I/Sec.I) 1985

500m 500C 350C 5 0C 600C 320C 100% 70 120 150cm

Wind Zones Light Medium Heavy

IS:5613 Part-I/Sec-I Terrain Category 100 Kg/m2 150 Kg/m2 200 Kg/m2

Environmentally, the region where the work will take place includes coastal areas,

subject to high relative humidity, which can give rise to condensation. Onshore winds will frequently

be salt laden. On occasions, the combination of salt and condensation may create pollution conditions

for outdoor insulators.

Therefore, outdoor material shall be designed and protected for use in exposed, heavily polluted salty

corrosive and humid coastal atmosphere.

4. SYSTEM CONDITIONS:

The materials shall be suitable for installation in supply systems of the following characteristics.

Frequency Nominal System Voltage Maximum System Voltage LV System Minimum LV Voltage Power frequency one minute withstand (set & dry) Neutral Earthing arrangement LV System

50Hz 400/230V 440/250 V 370 V 2KV

Solidly earthed

5.0

Part-2: TECHNICAL

GENERAL/ TECHNICAL The design of Aerial Bunched Cable offered shall comprise a compacted, standard,

hard drawn H2 / H4 grade aluminum phase conductor as applicable under IS-8130

/ 84 with cross linked polyethylene (XLPE) insulation 0.65 to 1.1. KV class, having of

carbon black content 2.5% ± 0.5%.

The sizes and number of cores required are:

3x50mm2 + 1x16mm2 + 1x35mm2 (catenaries type)

3x35mm2 + 1x16mm2 + 1x25mm2 ( catenaries type)

3x35mm2 + 1x25mm2

1x35mm2 + 1x25mm2

The type of Bunched Cables shall be three phase and street lighting insulated

bundled. All Aluminum Conductors combined with a neutral and catenaries (bare) which shall be of

heat treated aluminum magnesium silicon alloy wires containing approximately 0.5% each of

magnesium and silicon respectively. The catenaries must have an ultimate tensile stress of not less

than that specified in the table of technical requirements.

The Bidder shall specify the standard to which this bundle shall be manufactured.

The conductor bundle offered shall be designed to meet the requirements set out in

this specification taking note of safety factors pertaining to conductor or catenary tensioning and

NESC specification: General Technical Requirements for LV overhead lines.

However, a bid of Aerial Bunched Cables shall not be considered, unless it is

accompanied by a list of all special tools and equipments necessary to complete the installation.

6.0 CONDUCTORS:

(a) The phase & street light conductors shall be of multi -stranded aluminum of compacted

circular cross section. The aluminum shall comply with IS 8130:1984. The messenger

conductor shall be of multi-stranded Aluminum Alloy conforming to IS 398 ( Part 4 ) - 1994.

In addition to meeting all requirement of relevant ISS the LT XLPE AB Cables supplied shall

satisfy following general requirements.

FOR PHASE AND STREET LIGHT CONDUCTORS

Minimum. Over all dia.

Sl. No.

1

2

3

4

5

6

Specified Cross

Sectional Area (mm2)

16

25

35

50

70

95

No. of Stran ds

7

7

7

7 19

19

Minimum Dia Of each

strand in mm

1.75

2.14

2.54

3.05

2.18

2.54

Of conducting

part of the

compacted

conductor. (mm) 5.25 6.42 7.6

9.15

10.9

12.7

Maxm. D.C Registance at 20

degree centigrade.( Ohm / Km)

AS PER ISS / GTP

Nominal Insulation

thickness (mm)

1.2

1.2

1.2

1.5

1.5

1.5

FOR MESSANGER CONDUCTORS

Sl. No.

1

2

3

4

Phase Conductor Size of the

LT AB Cable in

mm2

16

50

70

95

Specified Cross

Sectional Area of the

Messanger

Conductor (mm2)

25

35

50

70

No. of Strands

7

7

7

7

Nominal

dia Of each

strand

2.14

2.54

3.05 3.6

Appx. Over all dia. Of

conducting

part of the

compacted

conductor. (mm)

5.2

7.6 9.15

10.8

Maxm. D.C Resistance of

the messenger at

20 degree centigrade.( Ohm / Km)

AS PER

ISS/GTP

Appx. Mass ( Kg / Km.)

for

the messanger

65

95 136

191.8

6.0 (b) The bidder must take required precaution to ensure that the average diameter of each

strand of conductor shall be ascertained through physical measurement of dimensions of finished

cables at ambient temperature during pre-dispatch inspection or / and verification at NESCO,

WESCO & SOUTHCO Store by consignee and the value so obtained shall have a tolerance limit

with reference to the nominal diameter of each strand of conductor as stated in the tables above.

7.0

8.0

TOLERANCES: The measurement of strand diameter of the finished AB Cable shall not be less

0.03mm for strands up to and including 3.00mm diameter. For strands above that size, measurement

of strand diameter shall not be less than 1% of the nominal strand diameter.

For the purpose of checking compliance with the above requirement, the diameter

shall be determined by two measurements at right angles taken at the same cross section. The

physical measurement of strands shall be conducted after opening the strands of a finished AB Cable

offered for inspection.

SPLICES IN WIRES:

Splices in Wires shall generally comply with requirements of IEC 1089. The aluminum alloy rods may be spliced by cold pressure but welding before drawing

provided the manufacturer can guarantee that the splice can develop 90% of the tensile strength of

the un sliced rod. Wires which break during stranding may be

sliced by cold pressure butt-welding provided that:

No two splices in the completed conductor occur within 15m of each other and no two

splices in any individual wire are less than 150m apart.

The splice shall be done with high skilled workmanship. The finished splice shall be

smooth and at no point shall the cross sectional area be less than that of the un sliced wire.

Splicing of the alloy wires on the stranding machine in order to utilize lengths of wires

on reels shall not be permitted.

9.0

10.0

11.0

STRANDING AND CORE LAY: The conductor cores shall be stranded and the direction of lay must be as defined in IEC: 1089. INSULATION: The Aerial Bunched Cables shall be insulated for a voltage class of 0.65/1.1 KV and

shall be capable of operating permanently at 1.2KV.

The insulation wall thickness shall be determined in accordance with Table-4 (Clause-

7.2 and Clause 7.3) of IS: 14255/1995.

The insulating material shall be black and suitable to resist ultra violet radiation, salt

laden sprays, chemical pollution, ageing effects, abrasion and mechanical shocks and

mechanical and electrical stress at temperature up to 90˚C in normal operation and

2500C under short circuit conditions per IEC: 502/1994.

The carbon black content in the XLPE insulation shall be 2.5% ± 0.5%

PHASE IDENTIFICATION: The individual insulated conductors within a bundle shall be identified by means of

longitudinal projections.

The three phase conductors shall be marked by one, two or three longitudinal

projections, indicating the red, yellow and blue phases.

The projections shall have the following dimensions.

The distance between the tips of two adjacent projections, where there is more

than one, shall be between 1.0 and 1.5.

The width of the projection at the base shall be 1.0mm; and

The height of the projections shall be 0.5mm.

12.0

INSULATION MARKINGS: Each individual conductor comprising a bundle shall have the range of non-erasable

distinct markings listed below legibly printed on the insulation surface at one meter intervals. The

embossing should be very clear & easily visible to naked eye.

ISI Mark, IS 14255-95, Manufacturer‟s B.I.S License No. legibly embossed on

the insulation.

Name of the Purchaser.

P.O No. & Date

Manufacturer‟s trademark identification for example "UCXLPE50"

Year of manufacture: last two digits are sufficient:

Designation of conductor type

Size: for example "3x50"

Shape of conductor.

Rated voltage class: 0.65/1.1KV

Back up conductor identification: conductors with one, two and three

projections shall be marked R, Y and B respectively. The conductor with no

projection shall be marked N and

The height of the printed lettering shall be not less than 20% of the overall

diameter of the conductor

The markings shall be made in the sequence indicated above.

Thus if the manufacturer were XY, the aerial bunched cable had been manufactured in 1994, size

3x50mm2 + 1x35mm2 + 1x16mm2 with conductors of circular cross section and with a bundle of the

self supporting type, manufactured to a recognized

international standard then the core with two projections would be marked as follows:

XY-04-NFA4X50+1X16-r-m-0.65/1.1KV-Y Where, N is the international standard, F indicates overhead cable, A is aluminum

alloy conductor and 2X refers to XLPE insulation, „r‟ means round core, „m‟ self-

supporting and „y‟ the phase identification.

13.0 14.0

15.0 15.1

15.2

TWIST: The direction of lay of the conductors comprising the bundle shall be left -handed and

the lay ration shall comply with IEC: 1089.

With a bare catenaries configuration the insulated phase cables together with the

street lighting cores shall be twisted round the neutral catenaries to form the ABC. This cable bundle

is then strung directly onto the distribution poles supported by the catenaries with standard approved

hardware.

CABLE DRUM LENGTH: The cable shall be supplied in 500m . Drum Lengths as the case may be for different

sizes of LT XLPE AB Cable.

TESTS:

General

Where not specified, all tests and test results shall conform to the requirements of IEC

502/1994 or IS 7098 (Part-I) 1998, IS 10810/1984, IS: 398(Part-IV) and IS:

14255/1955.

Unless expressly stated otherwise, the ambient temperature for routine tests as well as

voltage tests shall be 20 + 150C and for all other tests be 20 + 150C.

The frequency of the alternating test voltage shall be 49 Hz to 51Hz. The voltage wave

form should be sinusoidal.

Type Tests The test sample shall be 10m to 15m in length. All cores of the bundles shall be

tested.

Insulation resistance at ambient temperature.

Insulation resistance at operating temperature.

AC voltage test.

The insulation resistance test at ambient temperature shall be carried out in a water

bath at ambient temperature.

The insulation resistance test at a operating temperature shall be conducted in a

water bath at 900C.

The longitudinal projections used for phase identification shall be ignored. The results

of this test shall be used to calculate the volume receptivity and the results conform to the

requirements of IEC:502/1994 or IS 10810 (Part-43).

The AC voltage test shall be carried out by applying 1.95KV (3U0) for four hours to the

sample, which shall be submerged in a water bath at ambient temperature, having been steeped for a

period not less than one hour. The test shall only be deemed to have been passed if no breakdown

occurs.

Furthermore, the following non-electrical type tests shall also be carried out:

Insulation wall thickness: the longitudinal projections used for phase 1

identifications shall be ignored as per IS 10810 (Part-6);

Ageing test, consisting of an evaluation of the retention of the mechanical

properties of the insulation after ageing.

Wrapping test: as per IS 10810 (Part-3);

Tests for bleeding and blooming of pigment as per IS 10810 (Part-9)

Thermal expansion of insulation.

Measurement of carbon black content as per IS 10810 (Part-32).

Water absorption by the XLPE insulation, shrinking of the XLPE insulation.

Tensile test: adhesion between conductor and insulation.

The adhesion test requires a tensile testing machine. A sample of at least 300mm

length shall be selected and straightened out. The insulation shall be removed for a l ength of 150mm.

The insulated end shall be held in the upper grip head and the bare conductor on the lower grip head.

Tension shall be applied at a speed of 500mm/ min until the conductor first begins to slide within the

insulation. The test shall have been passed if the conductor and insulation combination can stand

75N/mm2 without slippage occurring.

The neutral conductor/catenaries shall be type tested in accordance with the

requirements of IS 398 (Part-IV) 1994.

15.3 15.4

Routine Tests The following measurement or tests shall be carried out on all drums and coils of

Bunched cable:

Conductor resistance

Voltage test.

The conductor to be tested for conductor resistance shall be stored for at least 12

hours in a room at particular constant temperature. If it cannot be established that the conductors

have reached the room temperature, the test should be postponed for a period of further 12 hours.

Alternatively, the test can be carried out on short sample after remaining one hour in a temperature

controlled water bath. The test shall be carried out and the conversion factors used to convert the

resistance value to a base of 2000C and one Km. The DC resistance of each conductor shall not

exceed the appropriate maximum values specified in IEC:228/IS:6474.

The voltage test shall be conducted by applying to each core 3.5KV AC (2.5 U 0 plus 2

KV) or 8.4 KV DC for 5 minutes with the specimen lying in a water bath at ambient

temperature. The conductor shall pass the test if no electrical breakdown occurs.

Acceptance Tests

The following sample check, measurements and test shall be carried out in addition to

the Acceptance Tests as per IS 14255 - 1955, IS : 398 ( Part - IV ) 1994, IS 8130 / 1984

Measurement of insulation wall thickness;

Measurement of diameter of each strand, overall outside dia & Cross Sectional

Area of the conducting Part out of the finished product during pre-dispatch inspection.

Thermal expansion test;

Check of physical characteristics

Tensile strength of individual wires of conductor.

High Voltage Test on drums immersed in water(apply voltage 3.5 KV AC for 5 min)

These tests should be carried out on one length form each production batch of the

same sample.

The thickness of the insulation wall shall be measured on a piece removed from each

end of the sample length. If either means or minimum values are not met, two further samples shall be

removed at 0.5m form the end corresponding to the failed specimen. If these samples do not satisfy

the mean and minimum thickness requirements, the test shall be deemed to have been failed.

The longitudinal projections used for phase identifications shall be ignored.

The thermal expansion test need only be carried out on one core.

In relation to the tensile test, the tensile strength of the aluminum wires before

stranding and that of the finished conductor shall comply with IEC:1089.

15.5

15.6

Test on the Catenary (messenger) Conductor Breaking load, elongation and resistance tests shall be completed on the aluminum

alloy catenaries conductor in accordance with the requirements of IS:398 (Part - IV)/1994 or

IEC:1089.

Bending Test on a complete cable This test shall be performed on a sample of completed cable. The sample shall be bent

around a test mandrel at room temperature for at least on turn. It shall then be unwound and the

process shall be repeated after turning the cable sample around its axis by 180 0. This process shall be

repeated twice more. There shall be no signs of breaking or cracking of the cable insulation during

this test.

The diameter of the mandrel shall be:

10 (D+d)

15.7

16.0

17.0 18.0

19.0

Where D = Actual diameter of the cable (mm)

d = Actual diameter of the conductor (mm)

Rejection and Retests Should any one of the test pieces first selected fail to pass the tests, two further

samples from the same batch shall be selected for testing, one of which shall be from the length from

which the original test sample was taken unless the length has been withdrawn by the supplier.

Should the test pieces from both of these additional samples satisfy the requirements

of the tests, the batch represented by these samples shall be deemed to comply with the standard.

Should the test pieces from either of the two additional samples fail, the batch represented shall be

deemed to have failed.

COMPLIANCE WITH SPECIFICATION:

The Aerial Bunched Cable shall comply in all respects with the requirements of this

specification. However, any minor departure from the provisions of the specification shall be

disclosed at the time of bidding in the Non-compliance Schedule of this document.

COMPLIANCE WITH REGULATIONS:

All the cables shall comply in all respects with the Indian Regulations and Acts in

force. The cables and connections shall be designed and arranged to minimize the risk of fire and any

damage, which might be caused in the event of fire.

Non-conforming Product

The Purchaser reserves the right for decisions regarding acceptance, modification or

rejection of non-conforming items.

Inspection and Testing The Purchaser or his authorized representative has free entry at all times, while work

on the contract is being performed, to all parts of the manufacturer‟s works which

concerns the processing of the cables ordered. The manufacturer shall afford the the

purchaser or his authorized representatives without charge, all reasonable facilities to

ensure that the cable being furnished is in accordance with these specifications.

The cables shall successfully pass all the type tests, routine tests & acceptance Tests

referred to in the section on tests and those listed in the most recent edition of the standards given in

the specification.

The Purchaser reserves the right to reject any of the cables if the test results do not

comply with the values specified or with the date given in the Technical data schedule.

Type tests shall be carried out at an independent testing laboratory or at the

manufacturer‟s works if such facilities are available and to be witnessed by the

purchaser. The contractor, at no extra cost at the manufacturer‟s work shall carry out

routine and Acceptance tests in presence of the Purchaser‟s representatives.

Type Test Certificates for the tests conducted earlier shall be submitted with the bid

for evaluation. The requirements of additional type tests will be at the discretion of the

Purchaser

The Purchaser may witness routine and type tests. In order to facilitate this, the

contractor shall give the purchaser of 15days notice that the material is ready for inspection &

testing. The supplier shall extend all assistance to the representative of the Purchaser during his

inspection & testing of samples at his works. The materials shall be dispatched only after approval

of such Test Reports and issue of Despatch clearance by the Purchaser. However the Purchaser

reserves the right to retest the materials after delivery at any NABL Accredited Testing Laboratory

in case of any disputes regarding size & quality of supplied materials at a later date during

guarantee period. The cost of such retesting shall be borne by the supplier.

All costs in connection with the testing, including any necessary retesting shall be

borne by the Contractor, who shall provide the Purchaser with all the test shall have the right to

select the samples for test and shall also have the right to ensure that the testing apparatus is correct.

Measuring apparatus for routine tests shall be calibrated at the expense of the contractor at an

approved laboratory and shall be approved by the purchaser before testing.

The Contractor shall be responsible for the proper testing of the materials supplied by

sub- Contractor to the same extent as if the materials were completed or supplied by the contractor.

Any cost incurred by the Purchaser in connection with inspection or retesting as a

result of failure of the equipment under test or damaged during transport or off loading shall be to

the account of the Contractor.

The Contractor shall submit to the Purchaser three signed copies of the test

Certificates, giving the results of the tests as required. No materials shall be dispatched until the

Purchaser has received the test certificate and the contractor has been informed that they are

acceptable.

The test certificate must show the actual values obtained from the tests, in the units

used in this specification, and most merely confirm that the requirements have been met.

In the case of components for which specific type tests or routine tests are not given in

this specification, the Contractor shall include a list of the tests normally required for these

components. All materials used in the Contract shall withstand and shall be certified to have

satisfactorily passed such tests.

No inspection or lack of inspection or passing by the Purchaser‟s representative of equipment

or materials whether supplied by the Contractor or sub- Contractor, shall

relieve the contractor from his liability to complete the contract works in accordance with contract or

exonerate him from any of his guarantees.

20.0 GUARANTEE:

The contractor shall guarantee the following:

Quality and strength of materials used.

Satisfactory operation during the guarantee period of 24 months from the date of

commissioning or 30 months from the date of receipt of the cables at

NESCO,whichever is earlier.

21.0 22.0

Performance figures as supplied by the bidder in the technical data sheet.

PACKING AND SHIPPING:

The cable shall be wound on strong drums or reels capable of withstanding all normal

transportation and handing.

PERMANENT EMBOSSING:

All equipments and materials supplied/erected shall bear distinct mark of "

NESCOand Purchase Order No & Date "by w a y o f e m b o s s i n g /punching/casting

etc.including o t h e r i n f o r m a t i o n mentioned in GTP. This should be clearly visible to

naked eye.

GUARANTEED TECHNICAL PARTICULARS FOR LT XLPE AB CABLES

Sl No

1 2

Description

Ref. ISS / IEC followed

Phase Conductor material / Insulation type

3X35 + 1X16 +1X25mm2

Requirement

IS 14255/95, IS 398 Part IV

H2 / H4 E.C grade aluminium as per

IS 8130/84 / XLPE insulation ( IS 14255/95)

3X 50 + 1X16 +

1X35 mm2

Requirement

IS 14255/95, IS 398 Part IV

H2 / H4 E.C grade aluminium as per

IS 8130/84 / XLPE insulation ( IS 14255/95)

3X 35 + 1X25

mm2

Requirement

IS 14255/95, IS 398 Part IV

H2 / H4 E.C grade aluminium

as per IS 8130/84 / XLPE

insulation

1x35+1x25 mm2

Requirement

IS 14255/95, IS 398 Part IV

H2 / H4 E.C grade aluminium as per IS 8130/84

/ XLPE insulation ( IS 14255/95)

3

4

Material of Neutral

Catenary

Voltage Class

No. of Strands of Phase Conductor

Aluminum alloy as per IS 398 Pt - IV

0.65/1.1 KV

7


0.65/1.1 KV

7

( IS 14255/95) Aluminum alloy as per IS 398 Pt -

IV

0.65/1.1 KV

7


0.65/1.1 KV

7

No. of strands/ Average

5

6

/Minimum Strand Dia. In mm. (Finished Phase

conductor.)

Approximate Overall Dia. Of compacted phase conductor after removal

7/2.52

7 .0

7/3.05

9.15

7/2.52

7 .0

7/2.52

7 .0

of insulation.(in mm.)

No. Of Strands / Average

7

8

Strand Dia. In mm. (

Neutral Catenary.)

Minimum Overall Dia. Of compacted Bare

Neutral Caternary .(in mm.)

7 / 2.15

6. 0

7/2.54

7.62

7/2.15

6 .0

7/2.15

6 .0

No. Of Strands / Average strand dia. / Nomunal

cross sectional area of 9

10

11

conducting part In No / mm2.

( St. Light Conductor) Minimum average

thickness of insulation of phase Cond. (mm)

Minimum thickness of insulation of Phase Cond.

7 /1.75 / 16mm2

1. 2

0 .9 8

7 /1.75 / 16mm2

1. 5

1.25

N.A

1. 2

0 .9 8

N.A

1. 2

0 .9 8

At any point (mm )

Minimum thickness of

insulation at any point 12 in street light conductor

(mm)

Maximum DC resistance

0.98 0.98 N.A N.A

13

14

of Phoase conductor at 20 C ohmn/ KM

Maximum DC resistance of street light conductor

Ω / Km

0.868

1.91

0.64

1.91

0.868

N.A

0.868 N.A

15 16 17

Maximum DC resistance of neutral cond. Ω / Km

Ultimate tensile strength of neutral conductor

(KN)

Maximum temperature (Continuous)

1 .3 8

7

90°C for phase and 75 °C for neutral

0.986

14

90°C for phase and

75 °C for neutral

1 .3 8

7

90°C for phase

and 75 °C for neutral

1 .3 8

7

90°C for phase and 75 °C for neutral

Distinct Non-

erasable ISI Mark, IS 14255-95,

Manufacturer‟s B.I.S License No.,

Distinct Non-

erasable ISI Mark, IS 14255-95,

Manufacturer‟s B.I.S License No.,

Distinct Non- erasable ISI

Mark, IS 14255- 95,

Manufacturer‟s B.I.S License

No., Name of the

Distinct Non- erasable

ISI Mark, IS 14255-95,

Manufacturer‟s B.I.S License No., Name of

the Purchaser, Name

18 Embossing on insulation

at each one meter interval

Name of the Purchaser, Name

of the manufacturer, Size

of cable, voltage

Grade along with

sequential

marking of length.

Name of the Purchaser, Name

of the manufacturer, Size

of cable, voltage

Grade along with

sequential

marking of length..

Purchaser, Name of the

manufacturer, Size of cable,

voltage Grade along with

sequential

of the manufacturer, Size of cable, voltage

Grade along with sequential

marking of length.

marking of length.

19

20

21

Cable drum length

Volume Resistivity of insulation at 27°C

Volume Resistivity of insulation at 70°C

500 m

1X1013Ώ - cm min.

1X1011Ώ - cm min.

500 m

1X1013Ώ - cm min.

1X1011Ώ - cm min.

500m

1X1013Ώ - cm min.

1X1011Ώ - cm min.

500 m

1X1013Ώ - cm min.

1X1011Ώ - cm min.

Sl. Name of the Particulars

31/2 C 185 mm2 LT unarmoured

AB cable

Bidd

er's

Offer

31/2 95 mm2 LT unarmoured

AB cable

Bidder

's

Offer

Aluminium

Aluminium

Type of

Conductor

1 Conductor ,XLPE

cable

,XLPE

Insulated

Insulated

2 Conductor

Details

a No of Cores 3 &1/2 3 &1/2

b Normal Cross-Sectional Area 31/2 185 sqmm 31/2 95 sq mm

c Material and Grade

Aluminium

compacted,Strande

d as per IS: 8130

with latest

amendment

Aluminium

compacted,Strande

d as per IS: 8130

with latest

amendment

d Shape of

Conductor Circular Circular

e As per REC

Spec. As per REC Spec.

No. of Strands and Diameter as per IS 8130

with

8130 with

f

of each Strand

latest amendment

latest

amendment

3 Rated Voltage 1.1 kV 1.1 kV

Maximum

900 C

900 C

4 Conductor temperature for

Maximum conductor

5 temperature during 2500C 250

0C

short circuit

6 Insulation

a Material XLPE XLPE

b Nominal Thickness

As per REC Spec.

As per REC

Spec

(Phase/ Neutral)

7 Vulcanization Process

a Curing Method Dry Curing Dry Curing

b Cooling Method Inert Gas Inert Gas

8 Inner Sheath

a Material

PVC

PVC

b Thick ness of inner sheath

(mm) As per REC As per REC

Diameter of Cable after

inner Manufacture

to Manufactur

e

c sheath application

Specify

to Specify

Outer Sheath

PVC PVC

9

PVC PVC

a Type

FR ST 2 as per IS FR ST 2 as

5831 per IS 5831

b Colour

Black

Black

c Thickness 2.2

2.2

Manufactur

10 Nominal OVerall Diameter of

Manufacture to Specify

Cable Specify

11 Nominal Overall Weight of

Manufacture to Manufacture

Cable per Metre Specify

to Specify

Minimum Bending Radius al

As per Is 1255 /

As per Is

1983

12 1255 / 1983 during installation with latest

amendment

Short Circuit Current

13 Rating of As per

REC As per

REC

f o r 1 S e c

14 Soil Parameter

a

Soil Temperature

C

C

Ambient

b Temperature C C

Soil Thermal

c Resistivity

C Cm/W C Cm/W

Normal current

rating

15 in ampere

Groun

a d

As per REC

As per REC

b Ducts As per REC As per REC

c Air As per REC As per REC

16 Maximum DC Resistance at

As per REC

As per REC

20°C ohm/km

17 Maximum AC Resistance at

As per REC

As per REC

90°C ohm/km

Reactance of As per REC

As per REC

18 Cable in in ohm/km

As per REC

capacitance of cable in

19 micro farad/km 0.29 0.29

Derating factor of Cable

20 installed As per IS

As per IS

TECHNICAL SPECIFICATION OF LT TWO CORE XLPE, UNARMOURED 16 SQMM CABLE IN SUB STATION

Sl.

Name of the Particulars 2x16SQMM Bidder's Offer No

1 Type of cable Aluminium Conductor, XLPE

Insulated

2 Conductor Details

a No of Cores 2

b Normal Cross -

2x16SQMM

Sectional Area


Aluminium compacted, Stranded as per IS: 8130

with latest amendment

d Shape of Conductor

Circular

e Diameter of Conductor 2X4.5 mm

No. of Strands and

f Diameter of each as per IS 8130 with latest

amendment Strand

3 Rated Voltage 1.1 kV

Maximum Conductor 90

0 C

4 temperature for continuous operation

Maximum conductor

5 temperature during 2500C

short circuit

6 Insulation

a Material XLPE

b Nominal Thickness 0.7 mm


a Curing Method Dry Curing

b Cooling Method Inert Gas

8 Inner Sheath

a Material

PVC

b Thick ness of inner

0.3

sheath (mm)

Diameter of Cable

c after inner sheath


application

Outer Sheath

PVC

9

a Type

FR ST 2 as per IS 5831

b Colour

Black

c Thickness 1.8

10 Nominal OVerall


Diameter of Cable

11 Nominal Overall Weight


of Cable per Metre

Minimum Bending As per Is 1255 / 1983

12 Radius allowable

with latest amendment

during installation


13 Rating for 1 Sec 1.5 kA

14 Soil Parameter

a Soil Temperature

C

b Ambient Temperature

C

Soil Thermal

c Resistivity C Cm/W

15 Normal current rating

in ampere

a Ground

78A

b Ducts 61A

c Air 70A

Maximum DC

16 Resistance at 20°C 1.91

ohm/km

Maximum AC

17 Resistance at 90°C 2.44

ohm/km

18 Reactance of

0.080

Cable in in ohm/km

19 capacitance of cable

0.18

in micro farad/km

20 De rating factor of

As per IS

Cable installed

Sl. Name of the Particulars

31/2 C 300mm2 LT unarmoured

AB cable

Bidd

er's

Offer

31/2 50 mm2 LT unarmoured

AB cable

Bidder

's

Offer

Aluminium

Aluminium

Type of

Conductor

1 Conductor ,XLPE

cable

,XLPE

Insulated

Insulated

2 Conductor

Details

a No of Cores 3 &1/2 3 &1/2

b Normal Cross-Sectional Area 31/2 300 sqmm 31/2 50 sq mm


Aluminium

compacted,Strande

d as per IS: 8130

with latest

amendment

Aluminium

compacted,Strande

d as per IS: 8130

with latest

amendment

d Shape of

Conductor Circular Circular

e As per REC

Spec. As per REC Spec.

No. of Strands and Diameter as per IS 8130

with

8130 with

f

of each Strand

latest amendment

latest

amendment

3 Rated Voltage 1.1 kV 1.1 kV

Maximum

900 C

900 C

4 Conductor temperature for

Maximum conductor

5 temperature during 2500C 250

0C

short circuit

6 Insulation

a Material XLPE XLPE

b Nominal Thickness

As per REC Spec.

As per REC

Spec

(Phase/ Neutral)


a Curing Method Dry Curing Dry Curing

b Cooling Method Inert Gas Inert Gas

8 Inner Sheath

a Material

PVC

PVC

b Thick ness of inner sheath

(mm) As per REC As per REC

Diameter of Cable after

inner Manufacture

to Manufactur

e

c sheath application

Specify

to Specify

Outer Sheath

PVC PVC

9

PVC PVC

a Type

FR ST 2 as per IS FR ST 2 as

5831 per IS 5831

b Colour

Black

Black

c Thickness 2.2

2.2

Manufactur

10 Nominal OVerall Diameter of


Cable Specify

11 Nominal Overall Weight of

Manufacture to Manufacture

Cable per Metre Specify

to Specify

Minimum Bending Radius al

As per Is 1255 /

As per Is

1983

12 1255 / 1983 during installation with latest

amendment


13 Rating of As per

REC As per

REC

f o r 1 S e c

14 Soil Parameter

a

Soil Temperature

C

C

Ambient

b Temperature C C

Soil Thermal

c Resistivity

C Cm/W C Cm/W

Normal current

rating

15 in ampere

Groun

a d

As per REC

As per REC

b Ducts As per REC As per REC

c Air As per REC As per REC

16 Maximum DC Resistance at

As per REC

As per REC

20°C ohm/km

17 Maximum AC Resistance at

As per REC

As per REC

90°C ohm/km

Reactance of As per REC

As per REC

18 Cable in in ohm/km

As per REC

capacitance of cable in

19 micro farad/km 0.29 0.29

Derating factor of Cable

20 installed As per IS

As per IS

11 / .25 KV, 16 KVA ( STAR RATED) ALUMINIUM WOUND DISTRIBUTION TRANSFORMER

1.0 SCOPE:-

1.1 This specification covers design, manufacturing, testing and delivery of 16 KVA, 11/0.25 single

phase, oil immersed, Oil Natural (ON) distribution transformer (Sealed type) confirming to

energy efficiency level-2 of IS 1180(Part-1): 2014 suitable for 11 KV and 50 Hz distribution

system.

1.2 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.

1.3 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.

1.4 The design and constructional aspects of materials shall not withstanding any anomalies,

discrepancies, omissions, in-completeness, etc. in these specifications and 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 stipulations in

that respect in the relevant Indian Standards, IEC standards, I.E. Rules, I.E. Act and other statutory

provisions.

1.5 The Bidder / supplier shall bind himself 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.

1.6 Tolerances:

The tolerance of guaranteed performance figures shall be as specified in the (Part-I) table 7 of latest

issue of IS 2026 or relevant International Standard except wherever specified otherwise in this

specification.

2.0 System Particulars:-

34

The transformers shall be suitable for outdoor installation with following system particulars and they should be suitable for service under fluctuations in supply voltage as permissible under

Indian Electricity Rules.

Nominal System Voltage : 11Kv

Corresponding Highest System Voltage : 12Kv

Neutral earthling : Solidly earthed

Frequency : 50Hz with + 5% tolerance

Number of phase : 1

3.0 SERVICE CONDITIONS:


maximum altitude above sea level 1,000m

maximum ambient air temperature 50° C

maximum daily average ambient air temperature 40° C

minimum ambient air temperature -5° C

maximum temperature attainable by an object exposed to the sun 60 ° C

maximum yearly weighted average ambient temperature 32° C

maximum relative humidity 100%

average number of thunderstorm days per annum (isokeraunic level) 70

average number of rainy days per annum 120

average annual rainfall 1500 mm

maximum wind pressure 260Kg / m2

Environmentally, the region where the equipment will be installed includes coastal areas, subject to high relative humidity, which can give rise to condensation. Onshore winds will frequently be salt laden. On occasions, the combination of salt and condensation may create pollution conditions for outdoor insulators. Therefore, outdoor material and equipment shall be designed and protected for use in exposed, heavily polluted, salty, corrosive, tropical and humid coastal atmosphere.

4.0 APPLICABLE STANDARDS:-

The design, manufacture and performance of the equipment shall comply with all currently

applicable statutes, regulations and safety codes.

The Distribution Transformers (Sealed type) shall conform to energy efficiency level-1 (3-Star

rated) of IS 1180(Part-I) 2014.

35

Unless otherwise specified, the equipment offered shall conform to latest applicable Indian, IEC,

British or U.S.A. Standards and in particular, to the following :-

a. IS 2026(Part I,II,IV)/1997,(Part-III)/1981,(Part- Power & Distribution Transformer

V)/1994

b. IS : 1180(Part-I) 2014 Single phase distribution transformers

16 KVA, 11/0.25KV Sealed type.

c. IS : 335 / 1993 New insulating oil – Specification (fourth

revision)

d. IS:2099/ 1986, IS:7421 – 1988, Bushing

IS:3347 (Part-I/Sec-2)-1979,

IS:3347 (part-I/Sec-I) – 1982

Amended up to date

e. IS 5 Colours for ready mixed paints and

enamels.

f. IS 13730 (part – 27) 1996 Specification for particular types of

winding wires.

g. IS : 3073 / 1974, IS : 3070 (part – II) Specifications for Lighting Arrestors

h. CBIP Publication No. 295:2006 Manual on transformers

In case of conflict arising out due to variations between the applicable standard and the standards

specified herein, the provisions of this specification should prevail. 5.0 Specific Technical requirement:

a) Standard KVA Ratings: - The standard ratings for transformer shall be 16 KVA.

b) Nominal voltage ratings: Primary voltage: 11KV, Secondary voltage: 0.250 KV.

c) Winding connections:-

i.

H.V.

Winding : Series

ii. L.V. Winding : Series / Parallel

d) Temperature Rise:

i. The temperature rise for top oil over an ambient temperature of 500 C should be 35

0

C maximum. i.e. Max. Temp. Of top oil shall not exceed 850 C.

ii. Temperature rise for winding over an ambient temperature of 500 C should be 40

0 C

maximum. i.e. Max. Temp. of winding shall not exceed 900 C.

e) No load voltage ratio: - The no load voltage ratio shall be 11000/250 Volts

f) Tapping: - No tap switch to be provided.

6.0 Design & construction

6.1 Core

i) The core shall be stacked type

a) For Stack core :- The core shall be of high prime grade cold rolled grain oriented (C.R.G.O)

annealed steel lamination 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

permanency of the core losses with continuous working or the transformers.

b) The construction of Top/Bottom yoke shall be one. No cut core shall be allowed by any

case.

ii) The grade of core laminations shall be CRGO, M3 Grade (0.23mm) or better. The grade

of core laminations shall be required to submit the manufacturer‟s test report showing the

watt Loss per kg and the thickness of the core lamination, to ascertain the quality of Core

materials. The purchaser reserves the right to get sample of the core material tested at any

Government recognized laboratory.

iii) The transformer core shall not be saturated for any value of V/f ratio to the extent of

112.5% of the rated value of V/f ratio (i.e. 11000/50 or 22000/50) (due to combined effect

of voltage and frequency) up to 12.5% without injurious heating at full load conditions and

will not get saturated. The bidder shall furnish necessary design data in support of this

situation.

iv) Core base and bottom yoke shall be supported with 40 x 5 mm MS plate of adequate size

properly bolted together.

v) Flux Density:-

Flux density should not be more than 1.50 Tesla at the rated voltage and frequency. The

value of the flux density allowed in the design shall be clearly stated in the offer along with

graph.

vi) The No load current at rated voltage shall not exceed the percentage given in Table below. 37

Sr. KVA

No. Rating At Rated Voltage At 112.5% Rated Voltage

1 16 2.0% of the full load current in LT winding 4.0% of the full load current

vii) Number of steps of core shall be of minimum 5 for 16 KVA transformers.

Note: In case if it is found at any stage that the core used is defective/second used/scrap

core or No load loss found to be more than stipulated limits, the supplier is liable for

imposing penalty and even blacklisting the firm at the discretion of Purchaser.

6.2 Winding:-

a) Materials: Double paper covered Aluminum conductor shall be used for HV and LV winding. b) Current Density: Current density for HV and LV winding or any part should not be more than

1.4 A/ sq.mm. c) L.V. Neutral formation shall be at top.

d) Vertical ducts & sufficient spacers should be provided between HV & LV windings. e) The current density of delta lead shall not exceed 0.8 A/mm

2

f) The no of LV coil and HV coil in one limb shall be 1 & 4 for 16 KVA transformers. 6.3 Losses:

The Losses shall not exceed the values given below

KVA Max. Total losses at Max. Total losses at 100%

50% load (W) load (W)

16 95 265

No tolerance for losses of 11/0.25 kV. Distribution transformers as per IS: 1180 (Part 1)2014. In

case the actual loss values exceed the above guaranteed values, the transformers shall be rejected at

the risk, cost and responsibility of the supplier.

The values guaranteed in G.T.P. for flux density, no load current at rated voltage, no load current at

112.5% of rated voltage and no load loss at rated voltage shall be individually met.

6.4 Insulation material & clearances:

a) Materials – Makes of Electrical grade insulating craft paper, press Board, Parma wood/ Haldi wood insulation shall be declared in GTP by the bidder. The test reports for all properties as per relevant I.S. amended up to date shall be submitted during inspection.

38

b) The electrical clearance between the winding and body of the tank (between inside surface of the tank and outside edge of the windings) should not be less than 25 mm for 11 KV class.

Minimum external clearances of bushing terminals

HV Ph to PH 255mm

Ph to E 140mm

LV Ph –to-Ph 75mm.

Ph to E 40mm

c) The clearance between HV coil & Top/Bottom yoke shall be 21 mm (min).

d) Inter coil insulation shall not be less than 6 mm.

e) The insulation between core & LV shall be 2.5 mm (min).

f) The insulation between HV coil & LV coil shall be 10 mm (min).

g) Minimum 6 nos. of wedges to be provided.

6.6 Impedance Value –

The percentage impedance at 750 C. shall be 4% for 16 KVA transformers with positive tolerance

of 10%. No negative tolerance on % impedance is allowed.

6.7 Tank 6.7.1 The transformer tank shall be made up of prime quality, High grade, low carbon steel plate &

suitable for welding. The transformer tank shall be of robust construction. All joints of tank and

fittings should 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 means of the lifting lugs provided.

Tank inside shall be painted by hot oil resistant varnish or paint. Top cover plate shall be slightly

sloping approximately 5 to 10 deg.Towards HV bushing and edges of cover plate should be bent

downwards so as to avoid entry of water through the cover plate gasket. The width of bend plate

shall be 25mm min. the top cover shall have no cut at point of lifting lug. The construction of

Single phase sealed type transformer tank shall be as per Clause No.15 of IS 1180(Part-1)2014

and should conform the pressure and vacuum requirement as per said IS.

Wall thickness : 3.15 mm. (min)

39

Top and bottom plate thickness : 5 mm. (min.)

6.7.2 All welding operations to be carried out by MIG process. 6.7.3 Lifting lugs: 2 no‟s for 16 KVA of MS plate of 10 mm thickness suitably shall be reinforced.

6.7.4 Vertical clearance: - The height of the tank shall be such that minimum vertical clearance up to the top cover plate is achieved from the top of yoke for the sealed type transformers.

7.0 PUNCHINGS: Non-erasable Punching and embossing of Volume of oil in litres, name of the

Purchaser- SOUTHCO, Orissa, Name of the Supplier – M/s -------------------------------, Year of

Manufacture, Guarantee Period and Sl. No. of each transformer is to be made on top core channel,

top cover, side walls and name plates of transformers.

7.0.1 3 STAR LEVEL: In addition to above, the supplied Distribution Transformers must contain 3

Star Level with style and information provided by the Bureau of Energy Efficiency (B.E.E), Ministry

of Power, Government of India. 8.0 Painting

8.1 All paints shall be applied in accordance with the paint manufacturer‟s recommendations.

Particular attention shall be paid to the following: 8.2 a) Proper storage to avoid exposure as well as extremes of temperature.

b) Surface preparation prior to painting. c) Mixing and thinning d) Application of paints and the recommended limit on time intervals between coats. e) Shelf life for storage.

8.3 All paints, when applied in normal full coat, shall be free from runs, sags, wrinkles, patchiness,

brush marks or other defects.

8.3.1 All primers shall be well marked into the surface, particularly in areas where painting is evident, and the first priming coat shall be applied as soon as possible after cleaning. The paint shall be applied by airless spray according to the manufacturer‟s recommendations. However, wherever airless spray is not possible, conventional spray be used with prior approval of purchaser.

8.3.2 The supplier shall, prior to painting protect nameplates, lettering gauges, sight glasses, light fittings

and similar such items.

8.4 Cleaning and Surface Preparation

8.4.1 After all machining, forming and welding has been completed, all steel work surfaces shall be

thoroughly cleaned of rust, scale, welding slag or spatter and other contamination prior to any painting.

40

8.4.2 Steel surfaces shall be prepared by Sand/Shot blast cleaning or Chemical cleaning by Seven tank process including Phosphating to the appropriate quality.

8.4.3 The pressure and Volume of the compressed air supply for the blast cleaning shall meet the work

requirements and shall be sufficiently free from all water contamination prior to any painting.

8.4.4 Chipping, scraping and steel wire brushing using manual or power driven tools cannot remove

firmly adherent mill-scale and shall only be used where blast cleaning is impractical.

8.5 Protective Coating

8.5.1 As soon as all items have been cleaned and within four hours of the subsequent drying, they shall

be given suitable anticorrosion protection.

8.6 Paint Material

Followings are the type of paints that may be suitably used for the items to be painted at shop and supply of matching paint to site:

i) Heat resistant paint (Hot oil proof) for inside surface.

ii) For external surfaces one coat of Thermo Setting Paint or 2 coats of Zinc chromate followed by 2 coats of P.U (Poly-urethene) paint. The color of the finishing coats shall be dark admiral gray.

8.7 Painting Procedure 8.7.1 All painting shall be carried out in conformity with both specifications and with the paint

manufacture‟s recommendations. All paints in any one particular system. Whether shop or site applied, shall originate from one paint manufacturer.

8.7.2 Particular attention shall be paid to the manufacturer‟s instructions on storage, mixing, thinning and pot life. The paint shall only be applied in the manner detailed by the manufacturer e.g. brush, roller, conventional or airless spray and shall be applied under the manufacturer‟s recommended conditions. Minimum and maximum time intervals between coats shall be closely followed.

8.7.3 All prepared steel surfaces should be primed before visible re-rusting occurs or within 4 hours whichever is sooner. Chemical treated steel surfaces shall be primed as soon as the surface is dry and while the surface is warm.

8.7.4 Where the quality of film is impaired by excess film thickness, (wrinkling, mud cracking or general softness) the supplier shall remove the unsatisfactory paint coatings and apply another. As a general rule, dry film thickness should not exceed the specified minimum dry film thickness by more than 25%. In all instances, where two or more coats of the same paints are specifies, such coatings may or may not be of contrasting colors.

8.7.5 Paint applied to items that are not be painted, shall be removed at supplier‟s expense, leaving the

surface clean, un-stained and undamaged.

41

8.8 Damages to Paints Work

Any damage occurring to any part of the painting scheme shall be made good to the same standard of corrosion protection and appearance as that originally employed. Any damaged paint work shall be made as follows:

a) The damaged area, together with an area extending 25mm around its boundary, shall be cleaned down to bare metal.

b) A priming coat shall immediately applied, followed by a full paint finish equal to that originally applied and extending 50mm around the perimeter of the originally damaged.

The repainted surface shall present a smooth surface. This shall be obtained by carefully chamfering the paint edges before & after priming.

8.9 Dry Film Thickness

To the maximum extent practicable, the coats shall be applied as a continuous film of uniform thickness and free of pores. Over-spray, skips, runs, sags and drips should be avoided. The different coats may or may not be same color.

Each coat of paint shall be allowed to harden before the next is applied as per manufacture‟s recommendations. Particular attention must be paid to full film thickness at edges.

The requirement for the dry film thickness(DFT) of paint and the material to be used shall be as given below:

Sl. Paint Type Area to be No of Total Dry film thickness(Min)

No painted Coats

1. Liquid paint

a) Zinc Chromate (Primer) Out side 01 30 micron

b) P.U. Paint (Finish Coat) Out side 02 45 each

c) Hot Oil paint

inside 01 35/10 micron

The colour of the finishing coat shall be Sky Blue/Dark admiral Gray/Deep Green or any other

colour as decided by the purchaser.

9.0 Heat Dissipation :

a) Heat dissipation by tank walls excluding top and bottom should be 500W / sq, m.

10.0 Mounting Arrangement :

a) The transformers shall be provided with two mounting lugs suitable for fixing the

transformer to a single pole by means of 2 bolts of 20 mm dia. The transformer shall also

42

be provided with base plates of 50x8 mm thickness for fixing the transformer on a platform.

10.1 Terminals :

Brass terminal stud of suitable size to carry 250 AMP for HT with necessary nuts, check-nuts and

plain thick tinned washer. Each HT bushing shall be provided with a bi-metallic terminal connector

to receive 25-100 sq mm AAAC. Brass terminal stud of suitable size to carry 250 A for LT with

necessary nuts, check-nuts and plain thick tinned washer.

10.2 Bushings & Connections :

10.2.1 For 11 KV, class 12KV bushing, shall be used and for 250 volts, 1.0 KV bushing shall be used.

Bushings of the same voltage class shall be interchangeable. 10.2.2 The minimum creep age distance for both HV & LV Bushings shall not be less than 25mm per

KV. 10.3 Internal Connections: 10.3.1 H.V. Winding:

In case of HV winding all jumpers from winding to bushing shall have cross section larger than winding conductor. Inter coil connection shall be by crimping and brazing.Lead from series joint shall be connected to

bushing rod by brazing only. The current density in series lead shall be less than 1.4 A/mm2

10.3.2 L.V. Winding:

i.) L.T. Series/parallel point shall be formed of Aluminum/Copper flat of sufficient length &

size. Lead from winding shall be connected to the flat by crimping and brazing. ii) For Aluminum windings, L&T Alkapee aluminum brazing rods with suitable flux shall be

used. 10.4 Terminal Marking Plates and Rating Plates :

Each transformer shall be provided with a rating plate of weatherproof material showing the

following items indelibly marked which should conform to the rating plate and terminal marking

plate for single phase transformers without taps as per IS:1180(Part-1)2014. type of transformer standard to which it is manufactured IS-1180(Part-1) 2014. manufacturer‟s name transformer serial number

43

year of manufacture rated frequency in Hz (50) rated voltages in KV (11/0.433) number of phases (3) rated power in KVA type of cooling (ONAN) rated currents in A vector group symbol (Dyn11) 1.2/50µs wave impulse voltage withstand level in KVp power frequency withstand voltage in KV

impedance voltage at rated current and frequency in percentage at 75 0 C at normal tap

Measured load loss in KW at rated current and at 75 0 C at normal tap

Measured no-load loss in KW at rated voltage and rated frequency Maximum total losses(in Watt) at 100% load Maximum total losses(in Watt) at 50% load

continuous ambient temperature at which ratings apply in 0C

top oil and winding temperature rise at rated load in 0C

winding connection diagram Total weight in kg with complete oil filled. total weight of the transformer without oil Volume of oil in litres. weight of core and windings in kg; and name of the purchaser SOUTHCO, DESI, PHULBANI, GoO. 10.5 Fittings (As per clause no.20 of IS 1180(Part-1)2014) :

The fittings on the transformers shall be as under:

1 Rating and diagram plate 1no.

2. Earthing terminals with lugs 2 no.

3. Lifting lugs 2 nos

4. Oil filling hole with cap (on cover) 1 no.

5. Thermometer pocket with cap 1 no.

6. mounting arrangement 2 no.

7. Arching Horn for HT bushing As required

8. Oil level gauge indicating 3 positions 1 no.

of oil marked as below : (on side wall)

44

Minimum (-) 50 C.

Normal 300 C

Maximum 980 C

9. HT & LT bushing & connectors

2 HT & 2 LT bushings. Each bushing

(HV

& LV) should be provided with 3 nos. of

brass nuts and 2 plain brass washers &

with bimetallic connectors of suitable

size.

10. Any other required fittings as per

above said IS for Single phase sealed

type transformer.

10.6 Transformer Oil

The transformers shall be supplied complete with first filling of transformer oil upto maximum

permissible level. The quantity of oil required for the first filling of the transformer and its full

specification shall be stated in the bid. The complete first filling shall be of new oil free from

inhibitors and additives up to maximum permissible level for the supplied Transformer. The

bidder shall quote the price of transformer including the cost of Transformer Oil required for

initial filling.

The insulating oil for the transformer shall be of EHV grade, generally conforming to IEC: 296/

BS: 148/ REC: 39/ 1993 or latest version of IS: 335/ 1983 whichever is more stringent. No

inhibitors shall be used in the oil. The dielectric strength of the oil shall not be less than 60 KV

at 2.5 mm. gap when tested in accordance with IS: 6792/ 1972. If an anti-oxidant inhibitor is

recommended, its use shall be subject to the purchaser‟s approval.

The design and materials used in the construction of the transformer shall be such as to reduce

the risk of the development of acidity in the oil.

The contractor shall warrant that oil furnished is in accordance with the following specifications.

Sl.No Characteristic Requirement Method of Test

01 Appearance The oil shall be clear & A representative sample of oil shall

transparent & free from be examined in a 100 mm thick

suspended matter or layer at ambient temp.

sediment

02 Density at 200C 0.89 g/cm

3 Max. IS:1448

03 Kinematic Viscosity at 27 CST IS:1448

45

27 deg. C Max

04 Interfacial tension at 0.03 N/m IS:6104

27deg.C Min.

05

Flash

Point 136 0C IS:1448

06 Pour Point Max. -6 0C IS:1448

07 Naturalization Value 0.03 mg KOH/gm IS:335

(Total Acidity) Max.

08 Electric strength 72.5 KV IS:6792

Breakdown (voltage)

Min.

09 Dielectric dissipation 0.03 Max IS:6262

factor tan delta at 900 C

10 Min specific resistance 35X1012

ohm cm (min.) IS:6103 (resistively) at 90 deg.C

11 Oxidation stability

12 Neutralization value 0.40mg KOH/g

after oxidation

13 Total sludge after 0.10% by weight max.

oxidation

14 Presence of oxidation The oil shall not contain anti- IS:335

Inhibitor oxidant Additives.

15 Water content Max: Less than 25ppm IS:2362

11.0 Test and Inspection:-

11.1 Testing facility

The bidder should have adequate testing facility for all routine and acceptance tests and also

arrangement for measurement of losses, resistance, etc. details of which will be enumerated in the

tender.

The inspector of the purchaser will witness routine, Acceptance & type tests. In order to facilitate

this, the manufacturer shall give a 15 days notice that the material is ready for inspection & testing.

The material shall be dispatched only after approval of such test reports and issue of Dispatch

clearances by the purchaser. However the purchaser reserves the right to retest the

transformers after delivery at any NABL Accredited Testing Laboratory in case of any

disputes regarding guaranteed specifications of supplied transformers at a later date during

guarantee period. The cost of such retesting shall be borne by the supplier.

11.2 Routine & Acceptance Tests:- 46

11.2.1 All transformers shall be subjected to the following tests at the manufacturer‟s works. The tests are

to be carried out in accordance with the details specified in IS 2026 or as agreed upon between the

purchaser and the manufacturer.

A) Measurement of winding resistance.

B) Ratio, polarity and phase relationship.

C) Impedance voltage. D) Load losses at 75⁰ C. E) No-load losses and No-load current. F) Insulation resistance. G) Induced over voltage withstand.

H) Separate source voltages withstand. I) Pressure and Oil leakage test. J)Maximum total losses at 50% load.

K) Maximum total losses at 100% load. 11.2.2 All the routine tests shall be conducted in the suppliers‟ laboratory at their cost.

11.2.3 Heat run test shall be arranged free of cost on the unit selected from the 1st

lot by Authorized Representative.

11.2.4 The calculations to confirm the thermal ability as per Clause no. 9.1 of latest IS: 2026 Part-I or

equivalent International Standard shall be submitted to our representative. 11.3 Type Tests :

The bidder should submit the report of following tests carried out in a NABL accredited laboratory:-

a) Temperature Rise Test

b) Short Circuit Test containing the measured no load loss and load loss. c) Impulse Test d) Pressure test

The balance type tests as stated below should be carried at the manufacturer‟s works invariably in

the presence of representative of the purchaser at the time of inspection from the first lot.

a. Temperature Rise Test.

b. Air pressure test as per clause no.21.5 of IS: 1180 (Part-I)/2014. c. Unbalanced current test.

47

In respect of the successful bidder, the purchaser reserves the right to demand repetition of some or

all the above tests in presence of the purchaser‟s representative. In case the unit fails in the type

tests or routine tests, the complete lot offered shall be rejected. 11.4 Submission Routine Test Certificate

The successful bidder shall submit the routine test certificate along with documentary evidence for

having paid the Excise Duty for the following raw materials viz. Oil, Aluminum, copper for

conductors, insulating materials, core materials, bushings at the time of routine testing of the fully

assembled transformer. 11.5 Stage Inspection

11.5.1 Supplier shall give 15 days‟ advance intimation to the purchaser to organize stage inspection in which assembly of core, windings and other core materials etc. would be inspected. In respect of raw materials such as core stamping, winding conductor, oil etc. successful bidder shall use these materials manufactured/supplied by the standard manufacturers and furnish the manufacturer‟s test certificates, as well as, proof of purchase from those manufacturers documentary evidence for having paid the excise duty for the information of the department. Purchaser will depute his representative at the time of stage inspection.

11.5.2 All the transformers from the offered lot will be tested for acceptance tests at factory, in the

presence of purchaser‟s representative before dispatch.

11.5.3 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 representatives at a reasonable time when the work is in progress. Inspection and acceptance of any equipment under this specification by the purchaser shall not relieve the supplier of his obligation of furnishing equipment in accordance with the specifications and shall not prevent subsequent rejection if the equipment is found to be defective.

11.5.4 The purchaser may at its option, open a transformer supplied to the Stores, in presence of supplier

at site or at Stores. If any of the technical particulars are seen to be in variance than the guaranteed technical particulars, the whole lot of transformer will be rejected without any liability on purchaser.

11.5.5 Testing of all Distribution Transformers for no load and full load losses.

After inspection of new transformers at factory for acceptance of the lot, all distribution

transformers from the lot will be tested for no load and full load losses at all stores. Bidder has the

liberty to be present at the time of testing.

11.5.6 Inspection & testing of Transformer Oil :

48

The bidder shall make arrangements for testing of transformer oil to be used in the transformers testing will be done in presence of purchaser‟s representative.

To ascertain quality of transformer oil, original manufacturer‟s test report should be furnished to (Testing) at the time of factory inspection for acceptance of the lot.

11.6 Rejection:-

Apart from rejection due to failure of the transformer to meet the specified test requirements the

transformer shall be liable for rejection on any one of the following reasons.

(i). Losses exceed the specified values mentioned in specification.

(ii). Impedance voltage value exceeds the guaranteed value plus tolerances as per

specification.

(iii). Type test are not carried out as per the specification.

(iv). Drawings are not submitted as per the specification.

(v). GTP not submitted as per the specification.

(vi). Heat dissipation calculation sheet are not submitted as per the specification. 11.7 Quality Assurance

a) The bidder shall invariably furnish Test certificates and information as following along with the

offer failing to which the offer will be rejected.

(i). Aluminum and copper conductor.

(ii). Transformer oil.

(iii). Core

(iv). Insulating paper

(v). Porcelain Bushings

(vi). Steel Plate used for Tank.

(vii). List of testing & measuring equipments indicating the make, type, year of manufacture,

Last date of Calibration, Name of the agency carried out the calibration etc. Purchaser

reserves the right to visit the works of manufacturer to ensure the available testing facility

prior to placement of order.

b) Names of the supplier for the raw materials, list of standard accordingly to which the raw materials

are tested, list of test normally carried out on raw materials in presence of bidder‟s representatives,

copies of type test certificates.

c) Information and copies of test certificate as in (i) above respect of bought out accessories including

terminal connectors.

49

d) List of manufacturing facilities available. In this list the bidder shall specifically mention whether

lapping machine, vacuum drying plant, air conditioned dust free room with positive air pressure for

provision of provision of insulation and winding etc. are available with him.

e) Level of automation achieved and list of areas where manual processing still exists.

f) List of areas in manufacturing process where stage inspection are normally carried out for quality

control and details of such tests and inspections.

g) Special features provided in the equipments to make it maintenance free.

h) List of testing equipment available with the bidder for final testing of transformers and test plant

limitation, if any, vis-à-vis the type, special acceptance and routine tests specified in the relevant

standards and the present specification.

11.8 Drawings:- A set of following drawings with all dimensions shall be submitted by the Bidder along with the offer :

a) General Dimensional drawing.

b) Core Assembly drawing. c) Internal Construction Drawing. d) Rating & Diagram Plate Drawing. e) HV/LV Bushings indicating measurement of creep age distances. f) Operation and Maintenance Manual.

The drawings shall be of A-3 (420x297mm) size only. The bidder should also supply along with his

offer the pamphlet / literatures etc. for fittings/accessories.

The bidder should not change design once offered as per A/T, Approved drawings and Type Test

Reports.

The successful Bidders shall submit complete set of Drawings of transformer in triplicate indicating

dimensions for approval and get approved it before offering 1st

stage inspection.

11.9 Performance Guarantee:

All transformers supplied against this specification shall be guaranteed for a period of 30 months

from the date of receipt at the consignee‟s Stores Center or 24 months from the date of

commissioning, whichever is earlier. However, any engineering error, omission, working

provisions, etc. which do not have any effect on the time period, shall be attended to as and when

observed / pointed out without any price implication.

50

12.0 COST DATA SHEET:-

The bidders shall submit the cost data sheets indicating the break up prices and quantity of each

raw material and components along with the unit rates required for manufacture the offered

transformers along with the offer. The cost data sheet format is enclosed herewith. If the rates

quoted are not justified with the cost data sheets, the offer shall not be considered for evaluation

and placement of the order.

13.0 NON COMPLIANCE SCHEDULE

On this schedule the bidder shall provide a list of non compliance with this specification, documenting the effects that such non compliance is likely to have on the equipment's life and operating characteristics. Each Non Compliance shall refer to the relevant clause of the specification.

Where there are no deviations from specifications, the bidder shall so indicate by stating "No deviations" in this schedule.

Clause No. Non Compliance

14.0 Type Test Certificates Schedule

14.1 On this schedule a list of the test certificates included with the bid shall be provided. Each certificate listed shall be referred to the relevant specification clause and item of equipment to which the test applies.

Sl. Particular Type Test Certificate Year of Test

No. of Test Ref

14.2 In case of any doubt in the Type test reports submitted by the bidder, the Purchaser reserves the

right to verify the original Type Test Reports, as well as to refer to the concerned laboratory directly without recourse to be bidder.

TECHNICAL SPECIFICATION FOR 16 KVA, 25 KVA, 63 KVA, 100 KVA 11/0.433 KV, STAR RATED DISTRIBUTION TRANSFORMER

PART 1: GENERAL

1. SCOPE 1.1 The specification covers the design, engineering, manufacture, stage inspection, testing, pre-delivery

inspection, supply, delivery, loading, unloading and performance requirements of 11/0.433 KV non-sealed

type aluminum wound BIS Energy Efficiency Level-2 & BEE Star-1 Distribution Transformers for outdoor use in the networks of SOUTHCO. The transformers shall be double wound, three phase, CRGO M3 Grade (0.23mm) or better, oil immersed with ONAN cooling with Oil filled up to maximum permissible level. The ratings required under this specification are 16 KVA,25 KVA, 63 KVA & 100

KVA with Aluminum windings.

1.2 The equipment offered should have been successfully type tested within five years from date of tender and the designs should have been in satisfactory operation for a period not less than three years as on the date of bid opening. Compliance shall be demonstrated by submitting with the bid, (i) authenticated copies of the type test reports and (ii) performance certificates from the users, specifically from Central Govt./ State Govt. or their undertakings.

1.3 The scope of supply should also include the provision of type test. Purchaser reserves the right to

waive type tests as indicated in the section on Quality Assurance, Inspection and Testing in this specification.

1.4 The transformer shall conform in all respects to highest standards of engineering, design, workmanship, this specification and the latest revisions of relevant standards at the time of offer and the Purchaser shall have the power to reject any work or material, which, in his judgment, is not in full accordance therewith.

2. CODES & STANDARDS 2.1 Except where modified by this specification, the transformers shall be designed, manufactured

and tested in accordance with the latest editions of the following standards. The Bidder may propose alternative standards, provided it is demonstrated that they give a degree of quality and performance equivalent to or better than the referenced standards. Whether to accept or reject any alternative standard shall be adjudged by the Purchaser. The Bidder shall furnish a copy of the alternative standard proposed along with the bid. If the alternative standard is in a language other than English, an English translation shall be submitted with the standard. In the case of conflict the order of precedence shall be 1) IEC or ISO Standards, 2) Indian Standards, 3) other alternative standards.

IEC/ISO Indian Standard Subject

IEC 71 Insulation Coordination

IEC 76 IS 2026 Power Transformers.

IS 1180(Part 1) Outdoor Three Phase Distribution Transformers up to 500 KVA, 11/ 0.4 KV, Non- Sealed Type.

IEC 137 IS 2099 Bushing for Alternating Voltages above 1000V.

IEC 156 Method of determining Electric Strength of Insulating Oils.

27 IEC 296 IS 335 Specification for Unused Mineral Insulating Oils for

Transformers and Switchgear.

IS 6792 Method of determination of electric strength of insulating oils. IEC 354 IS 6600 Loading Guide for oil immersed Transformers

IEC 437 Radio Influence Voltage Measurement.

IEC 551 Determination of Transformer and Reactor Sound Levels.

IEC 616 Terminal and Tapping markings for power transformers.

IEC 722 Guide to the Lightning and Switching impulse testing of Power Transformers and Reactors.

ISO 1460/BS 729 Galvanizing

This list is not to be considered exhaustive and reference to a particular standard or recommendation in this specification does not relieve the Supplier of the necessity of providing the goods complying with other relevant standards or recommendations.

3. SERVICE CONDITIONS


maximum altitude above sea level 1,000m

maximum ambient air temperature 50° C

maximum daily average ambient air temperature 40° C

minimum ambient air temperature -5° C

maximum temperature attainable by an object exposed to the sun 60 ° C

maximum yearly weighted average ambient temperature 32° C

maximum relative humidity 100%

average number of thunderstorm days per annum (isokeraunic level) 70

average number of rainy days per annum 120

average annual rainfall 1500 mm

maximum wind pressure 260Kg / m2

Environmentally, the region where the equipment will be installed includes coastal areas, subject to high relative humidity, which can give rise to condensation. Onshore winds will frequently be salt laden. On occasions, the combination of salt and condensation may create pollution conditions for outdoor insulators.

Therefore, outdoor material and equipment shall be designed and protected for use in exposed, heavily polluted, salty, corrosive, tropical and humid coastal atmosphere.

4. SYSTEM CONDITIONS:

The equipment shall be suitable for installation in supply systems of the following characteristics.

Frequency 50 Hz ± 5%

Nominal system voltages 11 KV System 11 KV

LV System 433/250 V

Maximum system voltages 11 KV System 12 KV

28

LV System 476 V

Minimum LV voltage (NEC) 392 V

Nominal short circuit apparent power of 11 KV System 500 MVA (IS: 2026)

the system

Insulation levels :

1.2/50 µ sec impulse withstand 11 KV System 95 KV peak (As Per

BEE, Clause No.10 )

Power frequency one minute withstand 11 KV System 28 KV (rms)

(wet and dry)

LV System 3 KV (rms)

Neutral earthing arrangements : LV System Solidly earthed 29

PART 2: TECHNICAL SPECIFIC TECHNICAL REQUIREMENTS 1 Rated KVA (ONAN rating) 2 No. of phases 3 Type of installation 4 Frequency 5 Cooling medium 6 Type of mounting 7 Rated voltage

a) High voltage winding b) Low voltage winding

8 Highest continuous system voltage a) Maximum system voltage ratio (HV / LV ) b) Rated voltage ratio (HV / LV )

9 No. of windings 10 Type of cooling 11 KVA Rating corresponding to

ONAN cooling system 12 Method of

connection: HV: LV:

13 Connection symbol 14 System earthing 15 Percentage impedance voltage on normal

tap and KVA base at 750 C corresponding

to HV/ LV rating and applicable tolerances :

16 Intended regular cyclic overloading

of windings 17 a) Anticipated unbalanced loading

b) Anticipated continuous loading of windings (HV / LV)

18 a) Type of tap changer

b) Range of taping 19 Neutral terminal to be brought out 20 Over Voltage operating capability

and duration 21 Maximum Flux Density in any part of the

core and yoke at rated KVA, rated voltage i.e 11 KV / 0.433 KV and system frequency of 50 HZ

22 Insulation levels for windings :-

16 KVA,25KVA. 63 KVA, 100 KVA

11/0.433 KV 3 Outdoor

50 Hz (± 5% ) Insulating Oil (ONAN)

On Channels.

11 KV 0.433 KV

12 KV / 0.476 KV 11 KV / 0.433 KV

Two winding Transformers

ONAN ( Oil natural / Air natural ) 100%

Delta Star

Dyn 11 Neutral of LV side to be solidly earthed.

28.3 Impedance + Tolerance %

+ 10% (No negative tolerance will be allowed)

As per IEC –76-1, Clause 4.2

Around 10%

110 % of rated current

NA

No Tap

On LV side only

112.5 % of rated voltage ( continuous )

1.5 Tesla

30

a) 1.2 / 50 microsecond wave shape Impulse withstand (KVP)

b) Power frequency voltage withstand

(KV-rms) 23 Type of winding insulation

a) HV winding

b) LV winding 24 Withstand time for three phase short circuit 25 Noise level at rated voltage and frequency 26 Permissible Temperature Rise over

ambient temperature of 500C

a) Of top oil measured by thermometer.

b) Of winding measured by resistance. 27 Minimum HV clearances in air (mm) :-

a) Phase to Phase

b) Phase to ground 28 Bushings & Terminals

a) HV winding line end

b) LV winding

29 Insulation level of bushing

a) Lightning Impulse withstand (KVP)

b) 1 Minute Power Frequency withstand voltage (KV –rms )

c) Creepage distance (mm) (minimum)

30 Material of HV & LV Conductor 31 Maximum current density for HV and

LV winding for rated current

32 Polarisation index i.e. ratio of megger

values at 600 sec. to 60 sec for HV to earth, L.V to earth and HV to LV.

33 Core Assembly

34 Transformer Max. Losses at 50%

rating load (Watts).

a) 25 KVA 190

b) 63 KVA 340

c) 100 KVA 475

d)

6. 16 KVA 135

TYPE OF TRANSFORMER

HV: 95 LV: N.A.

HV: 28 LV: 03

Uniform

Uniform

2 Seconds

As per NEMA Publication No. TR-1.

350C

400 C

280

140

12 KV oil filled porcelain communicating

type of bushings ( Antifog type )

0.4 KV porcelain type of bushing (Antifog type)

HV LV

95 Not applicable

28 3

25 mm/ KV

EC grade Aluminum

1.6 Amp/ mm2.

Shall be greater than or equal to 1.5, but less than or equal to „5‟.

Boltless type

Max. Losses at 100%

load (Watts).

635

1140

1650

440

31

6.1 The transformers shall be of core type construction, double wound, three phase,

oil immersed, 11/0.433KV, 50 Hz with natural oil and air cooling (ONAN) to

be used as step down transformers for out door use. The design of the tank,

fittings, bushings, etc shall be such that it will not be necessary to keep the

transformer energised to prevent deterioration as the transformers may be held

in reserve, outdoors, for many years.

7. PERFORMANCE , CAPACITY AND SHORT CIRCUIT RATINGS

7.1 The following ratings are covered under this specification

16 KVA,11/0.433KV,Aluminium wound

25 KVA,11/0.433 KV, Aluminum wound



7.2 The transformer shall be capable of supplying a continuous load equal to its

KVA rating, under the following conditions :

continuous steady load;

design at maximum ambient air temperature of 500C;

400 C average winding temperature rise and 35

0C top oil temperature rise

for conventional breathing transformers.

7.3 The transformer may be overloaded during emergency up to 150% of its

continuous rating in accordance with IEC Publication 354 or IS: 6600. Bushings

and other current-carrying parts shall also be designed for this condition.

7.4 The transformer shall be capable of withstanding for two seconds without

damage to any external short circuit, with the short circuit MVA available at the

terminals of either winding with rated voltage on the other winding. If short

circuit tests have been carried out on the particular design of transformer

7.5 offered, the test results shall be supplied with the bid.

7.6 The thermal ability to withstand short circuit shall be demonstrated by

calculation.

The transformer shall be capable of withstanding the thermal and dynamic

7.7 effects of short circuits, as specified in IEC 76-5 or IS: 2026: Ability to

withstand short circuits.

32

The maximum flux density in any part of the core and yoke at rated KVA,

Voltage and frequency shall not exceed 1.5 Tesla.

8. VOLTAGE RATIO & TAPPING RANGE

8.1 The transformers shall have the following ratio :-

the nominal voltage ratio shall be 11,000/ 433 V for 16 KVA 25 KVA, 63

KVA, 100

KVA 11/0.4KV transformers;

Tolerance on the voltage ratio shall be ± 0.5%.

for transformers up to 100 KVA, 11/0.4 KV no tap changer is required.

8.2 The bidder shall state in the technical schedule, the percentage regulation at full

load, power factor 1.0 and at full load, power factor 0.85 lagging.

Transformers shall be suitable for parallel operation with each other.

9. PERCENTAGE IMPEDANCE

9.1

The Percentage of Impedance at 75 0 C shall be 4.5 % for 16 KVA,25 KVA,63

KVA &

100 KVA transformers. No negative tolerance on percentage Impedance is

allowed.

10 LOSSES

The load losses shall not exceed the values given

below:-

KVA Rating Maximum losses at Maximum losses at

50% loading (Watts) 100% loading (Watts)

25 KVA 190 635

63 KVA 340 1140

100 KVA 475 1650

16 KVA 135 440 4.1 The above losses are maximum allowable and there should not be any positive

tolerance.

4.2 The offered transformer(s) should have been type-tested at CPRI/ NABL

Accredited laboratory. The bid shall be accompanied with type-test reports

(short circuit test and Impulse test) conducted at Central Power Research

Institute / NABL Accredited laboratory for the offered transformers within five

years from date of tender. The short circuit test report(s) must contain the

measured no load loss and load loss, determined by CPRI/ NABL Accredited

laboratory.

In case of any doubts, SOUTHCO reserves the right to verify the original type

test reports of CPRI/ NABL Accredited laboratory or ask the supplier to

conduct the type tests at CPRI/ NABL Accredited laboratory at his

(supplier‟s) cost for re-confirmation of the test results particularly no load

losses, load losses and percentage impedance.

5.1 If the bidder quotes lower values of losses than the CPRI‟s measured losses, he

has to prove the same by conducting the Impulse & short Circuit tests at CPRI/

NABL Accredited laboratory along with measurement of no load losses and

load losses at his own cost in presence of Purchaser‟ s authorized representative

without any financial liability to Purchaser.

5.2 However, if the loss figures will exceed the stipulated values as per

specification, the transformer(s) shall be out rightly rejected.

11. VECTOR GROUP

11.1 The transformers shall be connected delta-star, in accordance with vector group

reference Dyn11 of IEC - 76/ IS - 2026.

11.2 The LV neutral shall be brought out to a terminal bushing, which shall be

identical to the phase bushings in all respects.

12. LOSSES

12.1 Transformers would be out rightly rejected if losses exceed the values indicated

at clause-10 above.

13. FLUX DENSITY

The flux density at rated voltage & rated frequency shall not exceed. 1.5 Tesla. The

transformer must be capable of operating at 10% over voltage and at frequency of 48.5

Hz without saturation.

vii) INSULATION LEVELS

The insulation levels as defined in IEC 76-C/ IS: 2026 Insulation levels and dielectric

test shall apply as per Table 2:

Table 2 : Transformer insulation level

HV Winding LV Winding

Basic Impulse voltage Level (Kvp) (1.2/50 micro. sec. 95 Not

Wave ) Applicable

Power Frequency voltage withstand level, Wet and Dry 28 3

(KV)

Bushings and terminals shall be adequate for the winding insulation tests and shall flash

over externally before puncture or internal failure can occur.

2 NOISE LEVEL

The average noise level of the transformers shall not exceed 51db. The measurement

shall be carried out in accordance with IEC 551 at a distance of 300mm from the

envelope of the transformer.

3 RADIO INFLUENCE VOLTAGE

The maximum radio influence voltage shall be 250µ V, measured as specified in IEC

437.

17 CORE AND WINDINGS

17.1 Core

17.1.1 Stage level inspection for core construction shall be carried out by the owner.

Each lamination shall be insulated such that it will not deteriorate due to mechanical pressure 17.1.2 and the action of hot transformer oil.

17.1.3 The core shall be constructed from high grade, non-ageing, Cold Rolled Grain

Oriented (CRGO) silicon steel of M3 Grade (0.23mm) or HIB grade laminations

only. No other core materials shall be entertained. Bidders are requested to note that

35

only PRIME CORE M3 Grade (0.23mm) materials HIB grade are to be used. In no

case, second grade core material is to be used. The purchaser at his discretion, may

select samples from the core laminations and get the same tested in CPRI/ NABL

Accredited laboratory to prove the quality of the core material.

17.1.4 For the above purpose, the supplier shall have to offer every batch of core laminations

received from his Sub-Vendor along with Invoice of the sub-vendor, Mills test

certificate, packing list, Bill of landing, Bill of entry certificate to customs etc. towards

proof of prime core materials for verification by the Purchaser‟s representative without

any cost to the Purchaser. Besides, the contractor must mention in his bid about the type

of CRGO / Amorphous laminations to be utilized for the offered transformers along

with a copy of the specific core loss curve at different flux densities.

17.1.5 Core materials should be directly procured either from the manufacturer or through their

accredited marketing organization of repute, but not through any agent.

The core and winding shall be capable of withstanding shocks during transport,

installation and service. Provision shall be made to prevent movement of the core and

windings relative to the tank during these conditions and also during short circuits.

17.1.6 The design shall avoid the presence of pockets which would prevent the complete

emptying of the tank through the drain valve. The core material offered in the tender to

be checked for its correctness before core coil assembly. For this, the tendered must ask

for core and coil inspection before its tanking.

17.1.7 The laminations shall be free of all burrs and sharp projections. Each sheet shall have an

insulting coating resistant to the action of hot oil.

17.1.8

The insulation structure for the core to bolts and core to clamp plates shall be such as to withstand 2000 V DC voltage for one minute.

17.1.9 The completed core and coil shall be so assembled that the axis and the plane of the outer surface of the core

assemble shall not deviate from the vertical plane by more than 25mm.

17.1.10 All steel sections used for supporting the core shall be thoroughly shot or sand blasted, after cutting, drilling and welding.

17.1.11 The finally assembled core with all the clamping structures shall be free from deformation and shall not vibrate

during operation.

17.1.12 The core clamping structure shall be designed to minimize eddy current loss.

17.1.13 The framework and clamping arrangements shall be securely earthed.

36

17.1.14 The core shall be carefully assembled and rigidly clamped to ensure adequate mechanical strength.

17.1.15 Oil ducts shall be provided, where necessary, to ensure adequate cooling inside the core. The welding structure and

major insulation shall not obstruct the free flow of oil through such ducts.

17.1.16 The design of magnetic circuit shall be such as to avoid static discharges, development of short circuit paths within itself or to the earth clamping structure and production of flux component at right angle to the plane of the lamination, which may cause local heating. The supporting framework of the cores shall be so designed as to avoid the presence of pockets, which would prevent complete emptying of the tank through the drain valve or cause trapping of air during filling.

The construction is to be of boltless core type. The core shall be provided with lugs

17.1.17 suitable for lifting the complete core and coil assembly. The core and coil assembly

shall be so fixed in the tank that shifting will not occur during transport or short circuits.

17.2 INTERNAL EARTHING

All internal metal parts of the transformer, with the exception of individual laminations 17.2.1

and their individual clamping plates shall be earthed.

The top clamping structure shall be connected to the tank by a copper strap. The bottom 17.2.2

clamping structure shall be earthed by one or more the following methods:

17.2.3

17.2.4

a) By connection through vertical tie-rods to the top structure.

b) By direct metal to metal contact with the tank base. c) By a connection to the structure on the same side of the core as the main earth

connection to the tank.

The magnetic circuit shall be connected to the clamping structure at one point only and

this shall be brought out of the top cover of the transformer tank through a suitably rated

insulator. A disconnecting link shall be provided on transformer tank to facilitate

disconnections from ground for IR measurement purpose.

Coil clamping rings of metal at earth potential shall be connected to the adjacent core

clamping structure on the same side as the main earth connections.

17.3 Windings

17.3.1 Winding shall be subjected to a shrinking and seasoning process, so that no further shrinkage

occurs during service. Adjustable devices shall be provided for taking up possible shrinkage in service.

17.3.2 All low voltage windings for use in the circular coil concentric winding shall be wound

37

on a performed insulating cylinder for mechanical protection of the winding in handling

and placing around the core. 17.3.3

Winding shall not contain sharp bends which might damage the insulation or produce

high dielectric stresses. No strip conductor wound on edge shall have width exceeding

six times the thickness. 17.3.4

The winding insulation shall be free from insulating compounds which are liable to

soften, ooze out, shrink or collapse. It shall be non catalytic and chemically inert in hot

transformer oil during normal service. 17.3.5

The stacks of windings are to receive adequate shrinkage treatment. 17.3.6

The windings and connections are to be braced to withstand shocks during transport,

switching, short circuit or other transient conditions. 17.3.7 Permanent current carrying joints in the windings and leads shall be welded or brazed.

17.3.8 Clamping bolts for current carrying parts inside oil shall be made of oil resistant material which

shall not be affected by acidity in the oil steel bolts, if used, shall be suitably treated.

Terminals of all windings shall be brought out of the tank through bushings for external

17.3.9 connections.

The windings shall be uniformly insulated and the L.V neutral points shall be insulated

17.3.10 for full voltage.

The completed core and coil assemble shall be dried in vacuum at not more than 0.5mm of

mercury absolute pressure and shall be immediately impregnated with oil after the drying

process to ensure the elimination of air and moisture within the insulation. Vacuum may be

applied in either vacuum over or in the transformer tank.

17.3.11 The winding shall be so designed that all coil assembles of identical voltage ratings

shall be interchangeable and field repairs to the winding can be made readily without

special equipment. The coils shall have high dielectric strength.

17.3.12 Coils shall be made of continuous smooth high grade electrolytic copper or aluminium

conductor, shaped and braced to provide for expansion and contraction due to temperature

changes.

Adequate barriers shall be provided between coils and core and between high and low voltage

17.3.13 coil. End turn shall have additional protection against abnormal line disturbances.

The insulation of winding shall be designed to withstand voltage stress arising from

17.3.14 surge in transmission lines due to atmospheric or transient conditions caused by

switching etc 17.3.15 Tapping shall not be brought out from inside the coil or from intermediate turns and

shall be so arranged as to preserve as far as possible magnetic balance of transformer at

all voltage ratios.

17.3.16 Magnitude of impulse surges transferred from HV to LV windings by electro magnetic

induction and capacitance coupling shall be limited to BIL of LV winding.

17.3.17 The winding conductor shall be of Aluminum. The current density shall not exceed 1.6

Amp/ mm2 for aluminium at normal full load current.

6.7.2 BUSHINGS AND TERMINATIONS

6.7.5 Bushings

18.1.1 Bushings shall be of the outdoor type and easily replaceable. Cemented in types will not

be accepted. They shall be sufficiently robust to withstand normal transport and erection

hazards and shall confirm to IEC 137 /IS 3347 and 2099.

18.1.2 All bushings shall have a minimum creepage distance of 25 mm /KV and shall have a

continuous rating of 200% of the transformer rating. The protected creepage distance

shall not be less than 50% of the total.

The following minimum 11 KV clearance shall be provided:

External (Air) for 11 KV

Phase to phase 255 mm

Phase to earth 140 mm

18.1.3 The 11 KV bushings of transformers shall be provided with a bi-metallic terminal

connector or suitable device to receive 35 –100 mm2 AAAC or ACSR conductor

directly without any bi-metallic action. The dia of HT bushing stud should not be less

than 12.5 mm. 18.1.4

The secondary bushings of transformers shall be fitted with non ferrous threaded

terminals of dia not less than 20 mm. With the exception of brass the terminals shall be

protected from atmospheric deterioration by suitable tinning or by some other approved

coating. 18.1.5 The terminals are to be supplied with one 16mm bolt, one conic spring washer, one

matching flat washer, one nut and one lock nut for each hole in the terminal plate.

18.2 Bushing Labels

18.2.1 The HV bushings shall be labeled U, V and W and the LV bushing u, v, w and n.

Marking letters shall be at least 12 mm high. The means of marking shall be either,

engraved metal plate; or

etched anodized aluminum.

Phase identification by adhesive stickers shall not be acceptable. 18.2.2 If labeling is to be carried out on the tank, it is preferred that one plate be used rather

than individual markings for each phase, in order to prevent incorrect phase markings.

Labels shall conform to the requirements of the section on labels in this specification.

18.3 Earthing Terminals

All transformers shall be provided with two earthing terminals conforming to relevant

Standards and M12 ISO metric bolt and nut which shall be non ferrous. It shall include a

spring washer and lock washer.

18.4 LIGHTNING ARRESTORS

9 KV, 5KA metal oxide lightning arresters of reputed make conforming to IS-3070

Part-III, one number per phase shall be provided.(Under the HV bushing with GI

earth strip 25x4 mm connected to the body of the transformer with robust

clamping arrangement). Lightening arrestors with polymer insulators in

conformance with relevant IEC can also be used. 19 TANK FABRICATION

19.1 All transformer sizes, the tank shall be of bolted type construction in accordance with IS

1180 (Part 2).

The tank shall be at atmospheric pressure at an internal temperature of 100 C;

The tank shall be designed for an internal pressure of 100 Kg/ m2 at 50

0 C

ambient conditions. It shall be capable of withstanding an unlimited number of 24 hours cyclic variations of internal pressure from atmospheric to this value.

The tendered shall state the top oil temperature at which the tank internal

pressure shall reach the value of 100 kN/ m2 and the value of steady load which

will result in this top oil temperature with an ambient temperature of 450 C.

Adequate space shall be provided at the bottom of the tank for collection of sediments.

19.2 Transformer tanks of all types shall be designed so that the completed transformer can

be lifted and transported without permanent deformation or oil leakage. Stiffeners

provided on all the four side walls for rigidity should be so designed that there is no

accumulation of water.

19.3 The Tank shall be of rectangular shape with round edges fabricated from tested quality

mild steel plates with minimum thickness of 3.15 mm. for the side walls while top cover

and the bottom plate of the tank shall have a minimum thickness of 5 mm. The

transformer tank and the top cover shall be designed in such a manner as to leave no

external pockets in which water can log, or any internal pocket where air/ gas can

accumulate.

Edge of Top cover should be bend downwards so as to avoid water through cover plate

gasket. The width of the bend plate shall be 25mm minimum.

19.4 All sealing washers / gaskets shall be made of oil and heat resistant neoprene rubber or

neoprene bonded cork seals suitable for temperature as stipulated in this specification.

Surfaces at gasketted joints shall be such that an even face is presented to gasket,

thereby eliminating the necessity for the gasket to take up surface irregularities.

19.5 All pipes, radiators, stiffeners or corrugations which are welded to the tank wall shall be

welded externally and shall be double welded wherever possible. All welds shall be

stress relieved. 19.6 The transformer tank shall be complete with all accessories, lifting lugs etc. and shall be

designed to allow the complete transformer filled with oil to be lifted by crane or jacks

without risk of any damage and can be transported by Rail/ Road without straining any

joints and without causing any leakage of oil. 19.7 Provision of Cable End Box with suitable gland. 19.8 The height of the tank shall be such that minimum vertical clearance up to the top cover

plate of 80mm is achieved from the top of the yoke.

20 PRESSURE RELIEF DEVICE

Transformers shall be fitted with a pressure relief device in the form of explosion vent.

The tendered shall state the pressure at which it is designed to operate. 21 OIL LEVEL GAUGE

A suitable oil level gauge (Magnetic type of dia 100 mm) shall be fitted on the

transformers and so located that it can be easily read from ground level. The gauge fitted

with the conservator shall be graduated for temperatures of 50 C, 30

0 C and +98

0 C.

22 CONSERVATORS AND BREATHERS

All the transformers shall be provided with a conservator tank. 8.7.6 The conservator tank shall be so designed and located as to eliminate any trapping of air

in the transformer or pipe work. It shall be inclined at an angle of about 5 degrees to the

horizontal towards the drain plug and the pipe connecting the main tank to the

conservator should project about 20 mm above the bottom of the conservator so as to

create a sump for the collection of impurities. Minimum oil level corresponding to 50 C

shall be well above the sump level. 22.2

All transformers shall be fitted with a silica gel breather of weatherproof design at a

convenient height with oil seal at the bottom, draw in plug and filling holes with covers

to isolate the silica gel from the atmosphere. The breather pipe should be connected at

top of the conservator tank with two bends at right angles. The cover of the main tank

and bushings turrets shall be provided with air release plug to enable the trapped air to

be released.

23 FITTINGS AND ACCESSORIES 8.9 The following standard fittings and accessories shall be provided :

Rating, diagram and terminal marking plate. Two earthing terminals. Lifting lugs/ platform lugs.

Pressure relief device or explosion vent. Silica gel breather.

A magnetic oil level gauge 100 mm dia for all transformers indicating three position

( 3) of oil - minimum. 5 0 C, 30

0 C and 98

0 C.

Top filter valve with locking arrangement. Bottom filter valve with locking arrangement. Air release plugs at transformer top cover, bushing turrets etc.

Set of Radiators. Conservator Tank

Bi-metallic terminals on the bushings for connection with over head ACSR/ AAAC

conductor. The Specification and brief details of the salient features of these terminals

should be stated. 25 TRANSFORMER OIL

The transformers shall be supplied complete with first filling of transformer oil upto

maximum permissible level. The quantity of oil required for the first filling of the

transformer and its full specification shall be stated in the bid. The complete first filling

shall be of new oil free from inhibitors and additives up to maximum permissible level

for the supplied Transformer. The bidder shall quote the price of transformer including

the cost of Transformer Oil required for initial filling.

The insulating oil for the transformer shall be of EHV grade, generally conforming to

IEC: 296/ BS: 148/ REC: 39/ 1993 or latest version of IS: 335/ 1983 whichever is more

stringent. No inhibitors shall be used in the oil. The dielectric strength of the oil shall

not be less than 60 KV at 2.5 mm. gap when tested in accordance with IS: 6792/ 1972.

If an anti-oxidant inhibitor is recommended, its use shall be subject to the purchaser‟s

approval.

The design and materials used in the construction of the transformer shall be such as to reduce the risk of the development of acidity in the oil.

The contractor shall warrant that oil furnished is in accordance with the following

specifications.

S.No Characteristic Requirement Method of Test

01 Appearance The oil shall be clear & A representative sample of oil transparent&freefrom shall be examined in a 100 mm suspended matter or sediment thick layer at ambient temp.

02 Density at 200C 0.89 g/cm

3 Max. IS:1448

03 Kinematic Viscosity at 27 27 CST IS:1448 deg. C Max

04 Interfacial tension at 0.03 N/m IS:6104 27deg.C Min.

05 Flash Point 136 0C IS:1448

06 Pour Point Max. -6 0C IS:1448

07 Naturalization Value 0.03 mg KOH/gm IS:335 (Total Acidity) Max.

08 Electric strength 72.5 KV IS:6792 Breakdown (voltage) Min.

09 Dielectric dissipation 0.03 Max IS:6262 factor tan delta at 90

0 C

10 Min specific resistance 35X1012

ohm cm (min.) IS:6103 (resistively) at 90 deg.C

11 Oxidation stability

12 Neutralization value after 0.40mg KOH/g

oxidation

13 Total sludge after 0.10% by weight max.

oxidation

14 Presence of oxidation The oil shall not contain anti- IS:335 Inhibitor oxidant Additives.

15 Water content Max: Less than 25ppm IS:2362

26 RATING AND CONNECTION PLATE

Each transformer shall be provided with a rating plate of weatherproof material showing

the following items indelibly marked :

type of transformer

standard to which it is manufactured (preferably IEC 76)

manufacturer‟s name

transformer serial number

year of manufacture

rated frequency in Hz (50)

rated voltages in KV (11/0.433)

number of phases (3)

rated power in KVA

type of cooling (ONAN)

rated currents in A

vector group symbol (Dyn11)

1.2/50µs wave impulse voltage withstand level in KVp

power frequency withstand voltage in KV

impedance voltage at rated current and frequency in percentage at 75 0 C at normal

tap

Measured load loss in KW at rated current and at 75 0 C at normal tap

Measured no-load loss in KW at rated voltage and rated frequency

continuous ambient temperature at which ratings apply in 0C

top oil and winding temperature rise at rated load in 0C

winding connection diagram

Total weight in kg with complete oil filled.

total weight of the transformer with out oil

Volume of oil in litres.

weight of core and windings in kg; and

name of the purchaser

DISCOM, GoO, CAPEX Programme.

The rating plate shall conform to the requirements of the section of Labels in this

specification.

27. BASE MOUNTING ARRANGEMENT

The under base of all transformers up to 100 KVA capacity shall be provided with two

75x40 mm channels, 460 mm long with holes of 14 mm dia at a centre to centre distance

of 415 mm to make them suitable for fixing on a platform or plinth.

27 (a) PUNCHINGS: Non-erasable Punching and embossing of Volume of oil in litres, name of

the Purchaser- WESCO & SOUTHCO, Orissa, Name of the Supplier – M/s ------------

-------------------, Year of Manufacture, Guarantee Period ( i.e. 2 years from the date of

installation ) and Sl. No. of each transformer is to be made on top core channel, top

cover, side walls and name plates of transformers.

27 (b) 3 STAR LEVEL: In addition to above, the supplied Distribution Transformers must

contain 3 Star Level with style and information provided by the Bureu of Energy

Efficiency (B.E.E), Ministry of Power, Government of India.

28. PAINTING

10.2 All paints shall be applied in accordance with the paint manufacturer‟s recommendations. Particular attention shall be paid to the following:

10.3 a) Proper storage to avoid exposure as well as extremes of temperature.

Surface preparation prior to painting.

Mixing and thinning Application of paints and the recommended limit on time intervals between coats.

Shelf life for storage.

28.3 All paints, when applied in normal full coat, shall be free from runs, sags, wrinkles, patchiness, brush marks or other defects.

28.3.1 All primers shall be well marked into the surface, particularly in areas where painting is evident,

and the first priming coat shall be applied as soon as possible after cleaning. The paint shall be applied by airless spray according to the manufacturer‟s recommendations. However, wherever airless spray is not possible, conventional spray be used with prior approval of purchaser.

28.3.2 The supplier shall, prior to painting protect nameplates, lettering gauges, sight glasses, light

fittings and similar such items. 28.4 Cleaning and Surface Preparation 28.4.1 After all machining, forming and welding has been completed, all steel work surfaces shall be

thoroughly cleaned of rust, scale, welding slag or spatter and other contamination prior to any painting.

28.4.2 Steel surfaces shall be prepared by Sand/Shot blast cleaning or Chemical cleaning by Seven tank

process including Phosphating to the appropriate quality.

28.4.3 The pressure and Volume of the compressed air supply for the blast cleaning shall meet the work

requirements and shall be sufficiently free from all water contamination prior to any painting. 28.4.4 Chipping, scraping and steel wire brushing using manual or power driven tools cannot remove

firmly adherent mill-scale and shall only be used where blast cleaning is impractical. 28.5 Protective Coating

28.5.1 As soon as all items have been cleaned and within four hours of the subsequent drying, they shall

be given suitable anticorrosion protection. 10.5 Paint Material

Followings are the type of paints that may be suitably used for the items to be painted at shop and supply of matching paint to site:

i Heat resistant paint (Hot oil proof) for inside surface.

ii For external surfaces one coat of Thermo Setting Paint or 2 coats of Zinc chromate followed by 2

coats of P.U (Poly-urethene) paint. The color of the finishing coats shall be dark admiral gray.

10.6 Painting Procedure

All painting shall be carried out in conformity with both specifications and with the paint

manufacture‟s recommendations. All paints in any one particular system. Whether shop or site applied, shall originate from one paint manufacturer.

Particular attention shall be paid to the manufacture‟s instructions on storage, mixing, thinning

and pot life. The paint shall only be applied in the manner detailed by the manufacturer e.g. brush, roller, conventional or airless spray and shall be applied under the manufacturer‟s recommended conditions. Minimum and maximum time intervals between coats shall be closely followed.

All prepared steel surfaces should be primed before visible re-rusting occurs or within 4 hours

whichever is sooner. Chemical treated steel surfaces shall be primed as soon as the surface is dry and while the surface is warm.

46

Where the quality of film is impaired by excess film thickness, (wrinkling, mud cracking or general softness) the supplier shall remove the unsatisfactory paint coatings and apply another. As a general rule, dry film thickness should not exceed the specified minimum dry film thickness by more than 25%. In all instances, where two or more coats of the same paints are specifies, such coatings may or may not be of contrasting colors.

Paint applied to items that are not be painted, shall be removed at supplier‟s expense, leaving the

surface clean, un-stained and undamaged. 10.6 Damages to Paints Work

Any damage occurring to any part of the painting scheme shall be made good to the same standard of corrosion protection and appearance as that originally employed.

Any damaged paint work shall be made as follows:

The damaged area, together with an area extending 25mm around its boundary, shall be cleaned down to bare metal.

A priming coat shall immediately applied, followed by a full paint finish equal to that originally applied and extending 50mm around the perimeter of the originally damaged.

The repainted surface shall present a smooth surface. This shall be obtained by carefully chamfering the paint edges before & after priming.

28.9 Dry Film Thickness

To the maximum extent practicable, the coats shall be applied as a continuous film of uniform thickness and free of pores. Over-spray, skips, runs, sags and drips should be avoided. The different coats may or may not be same color.

Each coat of paint shall be allowed to harden before the next is applied as per manufacture‟s recommendations. Particular attention must be paid to full film thickness at edges.

The requirement for the dry film thickness(DFT) of paint and the material to be used shall be as given below:

Sl. Paint Type Area to be No of Total Dry film No painted Coats thickness(Min) 1. Liquid paint

a) Zinc Chromate Out side 01 30 micron (Primer)

b) P.U. Paint (Finish Out side 02 45 each Coat)

c) Hot Oil paint inside 01 35/10 micron

The colour of the finishing coat shall be Sky Blue/ Dark Admiral Gray/ Deep Green or

any other colour as decided by the Purchaser 29 SEALING GASKETS

All sealing washers / gaskets shall be made of oil and heat-resistant Nitrile/ Neoprene rubber/

synthetic rubber bonded cork type RC-70C gaskets. Gaskets made of natural rubber or cork

sheet are not permissible.

30 SUPRESSION OF HARMONICS 47

The transformer shall be designed with attention to the suppression of harmonic voltage,

especially the third and fifth. 31 TESTS 31.1 Routine Tests

Routine tests shall be carried out on all transformers and the tests shall be conducted in

accordance with relevant National/ International Standards. No sampling is allowed. In

addition, tank tests in accordance with IS: 1180 shall be carried out.

The following routine measurements and tests shall be carried out in presence of Purchaser‟s

authorized representative(s):

a) Measurement of winding resistance.

b) Voltage ratio measurement and check of polarity and vector group. Bushing positions

shall have permanent markings at this stage of production;

c) measurement of impedance voltages/ short circuit impedance at rated current and

frequency

d) measurement of load loss at full load and 750C;

e) measurement of neutral unbalance current;

f) Temperature rise test on one transformer of each rating and measurement of hot

resistance.

g) measurement of no-load loss and no-load currents at full, 50%, 75%, 90%, 110%, 112.5%

and 120% of rated voltages;

h) induced over voltage withstand test at 22KV for 60 sec on the HV windings;

i) power frequency voltage withstand tests on HV and LV windings;

j) magnetic balance test

k) Polarization Index test P.I. value shall be not less than 1.5. P.I. = IR at 600 sec / IR at 60

sec.

l) oil leakage test : The criterion of leakage shall be discoloration by oil of whitewash

applied externally to suspected parts at an oil temperature of 900C or other method, as

approved by the Purchaser;

m) Pressure test on transformer tank on one unit for each rating.

Bushings and oil shall be subject to the following routine

tests. n) bushing routine test: in accordance with IEC 137/IS 3347;

48

o) Oil dielectric and moisture content test: conforming to IEC 156 or IS 335.

Routine test certificates shall include in addition to the test results, the purchaser‟s order

number, the transformer serial number, outline drawing number and transformer KVA rating.

Any other applicable tests shall be conducted at the discretion of the Purchaser without any

extra cost to Purchaser.

31.2 Type Tests 31.2.1 The measurements and tests should be carried out in accordance with the standard specified in

each case as indicated in the following table if the same tests were not conducted earlier at

CPRI or any NABL accredited Laboratory on the transformers of the offered design.

Table 6: Transformer type tests

Type Test Standard

Temperature Rise Test IEC 76/IS

2026/IS6600

Impulse Voltage Withstand Test, including Full Waves and IEC 76/IS 2026 Chopped Waves as listed below

Noise Level Measurement IEC 551

Short Circuit Test IEC 76 / IS 2026

In accordance with IEC 76-3 the following sequence of impulses should have been/

should be applied;

one full wave at 50% BIL; one full wave at 100% BIL; one chopped wave at 50% BIL

two chopped waves at 100% BIL and two full waves at 100% BIL.

31.2.2 If the type test report(s) submitted by the bidder do not fulfill the criteria, as stipulated

in this technical specification/ Bidder‟s offer, the relevant type test(s) has/ have to be

conducted by the Bidder at his own cost in CPRI/ NABL accredited laboratory in the

presence of purchasers representative(s) without any financial liability to purchaser in

the event of order placed on him.

11.4 Even if the Type test report(s) confirm(s) the Purchaser‟s specification, the Purchaser at

his discretion may ask the Supplier to repeat any or all specified type tests at CPRI/

NABL accredited laboratory on sample(s), selected at random by the purchaser‟s

representative(s) out of the offered quantity (first lot i.e. minimum one third of the total

ordered quantity). The type test(s) are to be test-witnessed by the Purchaser‟s

representative(s). For such type of repetition of type tests, the Bidder may quote Type

Test Charges in the enclosed Price Schedule or conduct the tests free of cost. 11.5 The supplier shall furnish calculations in accordance with IS: 2026 to demonstrate the

Thermal ability of the transformers to withstand Short Circuit forces.

31.3 CHALLENGE TESTING:

The manufacturer can also request challenge testing for any test based on the

specification and measurement of no load losses, load losses & impedance at 750C. The

challenger would request for testing with testing fees. The challenge test fees are

proposed to be at least three times the cost of testing. This is likely to deter unnecessary

challenges. The challenger would have the opportunity to select the sample from the

store and any such challenge should be made within the guarantee period. The party

challenged, challenger and the utility could witness the challenge testing.

The challenge testing would cover the following tests:

1. Measurement of magnetizing current & No Load losses at rated voltage & frequency.

2. Load Losses at more than 50% loading to determine the Full Load losses &

percentage impedance at 750C and neutral unbalance current.

3. Temperature Rise Test.

The challenge test could be conducted at NABL Laboratory like ERDA and CPRI. If the

values are within the limits the product gets confirmed else not confirmed. No positive

tolerances in losses are permitted. If the product is not confirmed the manufacturer

would pay the challenge fee and the challenger would get the fee refunded. However as

a redressal system the challenged would be allowed to ask for fresh testing of two or

more samples from the store and the same be tested in NABL Laboratory or CPRI in

presence of the party challenged, challenger and the utility.

If any one of the above two samples does not confirm the test, then the product is said to

have failed the test. In such cases the manufacturer will be declared as unsuccessful

manufacturer for the said product with wide publicity and would not be allowed to

compete in tenders of the purchaser for a period of at least three years and heavy penalty

would be imposed.

31.4 TEST VOLTAGE

Transformers shall be capable of withstanding the Power frequency and Impulse test

voltage as described below:

Nominal Highest Impulse Test Power frequency test

system voltage System voltage voltage voltage

433 V (rms) 3 KV (rms)

11 KV (rms) 12 KV (rms) 95 KV (Peak) 28 KV (rms)

32 COMPLIANCE WITH SPECIFICATION

The transformers shall comply in all respects with the requirements of this specification.

However, any minor departure from the provisions of the specification shall be disclosed

at the time of tendering in the Non Compliance Schedule as in Annexure-3, Section- V of

this document.

33 COMPLIANCE WITH REGULATIONS

All the equipment shall comply in all respects with the Indian Regulations and acts in

force.

The equipment and connections shall be designed and arranged to minimize the risk of

fire and any damage which might be caused in the event of fire.

34 INSPECTION AND TESTING 34.1 The Purchaser shall have free entry at all times, while work on the contract is being

performed, to all parts of the manufacturer‟s works which concern the processing of the

equipment ordered. The manufacturer shall afford the Purchaser without charge, all

reasonable facilities to assure that the equipment being furnished is in accordance with

this specification. After approval of Drawings by the Purchaser, the manufacture shall

manufacture a Prototype Model as per the Approved Drawing and offer the same for

inspection. The Inspection of the Prototype Model shall be carried out as per the Format

prescribed at Clause 41, Section-IV of our Tender Specification. The Supplier shall offer

the core, windings and tanks of each transformer for inspection by the Purchaser‟s

representative(s). During stage inspection of the Prototype Model, all the measurements

like diameter, window, height, leg centre, stack width, stack thickness, thickness of

laminations etc for core assembly, conductor size, insulation thickness, I.D., O.D.,

Winding height, major and minor insulations for both HV and LV windings, length,

breadth, height and thickness of plates of transformer tanks, the quality of fittings and

accessories will be taken/ determined.

The Inspection Report for the Tests conducted by our Authorized Inspectors in

presence of the manufacturer‟s representative, for the Prototype Model offered for

inspection with suggested modifications, if any shall be submitted to the undersigned for

approval.

After Inspection, the Prototype Model shall be kept sealed, in the premises of the

manufacturer till the completion of delivery of final consignment, for future reference

during subsequent Inspections.

The Supplier can offer for final inspection of the transformers subject to clearance of the

stage inspection report by the Purchaser.

34.2 The equipment shall successfully pass all the type tests and routine tests mentioned in the

above Clauses and those listed in the most recent edition of the standards given in Clause

2, of this specification.

34.3 The Purchaser reserves the right to reject an item of equipment if the test results do not

comply with the values specified or with the data given in the technical data schedule.

34.4 Routine tests shall be carried out by the Supplier at no extra charge at their works.

Adequate facility with calibrated testing equipment must be provided by the

manufacturer free of cost to carry out the tests. Type test certificates must be furnished

along with the tender for reference of the Purchaser.

34.5 The Purchaser will witness all required tests. In order to facilitate this, the Supplier shall

give the Purchaser a minimum of two weeks notice as mentioned in clause-7(ii) of

General Terms and Condition of Contract (GTCC) that the materials are ready for

testing. If the Purchaser does not indicate his intention to participate in the testing, the

manufacturer may proceed with the tests only after receipt of written confirmation to this

effect from the Purchaser and shall furnish the results thereof to the Purchaser

consequent upon such testing.

34.6 Full details of the proposed methods of testing, including connection diagrams, shall be

submitted to the Purchaser by the Supplier for approval, at least one month before

testing.

All costs in connection with the testing, including any necessary re-testing, shall be

borne by the Supplier who shall provide the Purchaser with all the test facilities which

the latter may require, free of charge. The Purchaser shall have the right to select the

samples for test and shall also have the right to assure that the testing apparatus is duly

calibrated and correct. Measuring apparatus for routine tests shall be calibrated at the

expense of the Supplier at an approved laboratory and shall be approved by the

Purchaser.

34.7 The supplier shall submit to the Purchaser five signed copies of the test certificates,

giving the results of the tests as required. No materials shall be dispatched until the test

certificates have been received by the Purchaser and the Supplier has been informed that

they are acceptable.

The test certificates must show the actual values obtained from the tests, in the units used

in this specification, and not merely confirm that the requirements have been met.

In the case of components for which specific type tests or routine tests are not given in

this specification or in the quoted standards in Clause 2, of this specification, The

Supplier shall include a list of the tests normally required for these components. All

materials used in the Contract shall withstand and shall be certified to have satisfactorily

passed such tests.

34.8 The Purchaser at his discretion may re-confirm the Routine Test Results, particularly no

load losses, load losses and percentage impedance in his own laboratory or laboratory of

his choice.

No inspection or lack of inspection or passing by the Purchaser‟s Representative of

equipment or materials whether supplied by the Supplier or sub-supplier, shall relieve the

Supplier from his liability to complete the contract works in accordance with the contract

or exonerate him from any of his guarantees.

However in case of future discrepancy, if any, after acceptance of equipments,

observed at any stage during guarantee period, the matter may be referred to

Bureau of Energy Efficiency (B.E.E) for random testing of equipments supplied. In

such cases the observation of B.E.E shall be binding to both parties.

d) GUARANTEE

The supplier shall guarantee the following:

Quality and strength of materials used;

Satisfactory operation during the guarantee period of two years (24 months) from the

date of commissioning, or 30 months from the date of acceptance of the equipment

by the Purchaser following delivery, whichever is earlier;

Performance figures as supplied by the tendered in the schedule of guaranteed particulars; The offered surface treatment shall protect the treated metal from corrosion for a

period of not less than five years from the date of delivery. e) PACKING AND SHIPPING i) Packing

The equipment and any supporting structures are to be transported adequately sealed

against water ingress. All accessories and spares shall be packed and securely clamped

against movement in robust, wooden, non returnable packing cases to ensure safe transit

in rough terrain, cross country road conditions and in heavy rains from the

manufacturer‟s works to the work sites/ earmarked destinations.

11.9 All accessories shall be carefully packed so that they are fully protected during transport

and handling operations and in storage. Internal surfaces of loose accessories shall be

sealed by means of gaskets and blanking off plates. All parts liable to rust shall receive

an anti-rusting coat and shall be suitably protected. It shall be the responsibility of the

Supplier to make good any damage caused through insufficient packing.

Each packing case shall be indelibly marked, on two adjacent sides and on the top, with

the following:

Individual serial number; Purchaser‟s name; Contract number; Destination; A colour coded marking to indicate destination; Supplier‟s name; Name and address of supplier‟s agent in Orissa; Description and numbers of contents; Manufacturer‟s name; Country of origin; Case measurements; Gross and net weight in kilograms: and All necessary slinging and stacking instructions.

g) Each crate or container shall be marked clearly on the outside of the case to show TOP

and BOTTOM positions with appropriate signs to indicate where the mass is bearing and

the correct positions for slings. All component parts which are separately transported

shall have permanent identification marks to facilitate correct matching and assembly at

site. Welded parts shall be marked before welding. Six copies of each packing list shall

be sent to the Purchaser prior to dispatching the equipment.

11.10 Transportation

The Supplier shall be responsible for the transport of all plant and equipment supplied by

them and for the transport of all goods to the various specified destinations including all

road clearance, offloading, warehousing and insurance.

The Supplier shall inform himself fully as to all relevant transport facilities and

requirements and loading gauges and ensure that the equipment as packed for transport

conform to these limitations. The Supplier shall also be responsible for verifying the

access facilities specified.

The Supplier shall be responsible for the transportation of all loads associated with the

contract works and shall take all reasonable steps to prevent any highways or bridges

from being damaged by his traffic and shall select routes, choose and use vehicles and

restrict and distribute loads so that the risk of damage shall be avoided. The Supplier

shall immediately report to the Purchaser any claims made against the Supplier arising

out of alleged damage to a highway or bridge.

All transport accessories, such as riding lugs, jacking pads or blanking off plates shall

become the property of the Purchaser.

All items of equipment shall be securely clamped against movement to ensure safe

transit from the manufacturer‟s facilities to the specified destinations.

The Supplier shall advice the storage requirements for any plant and equipment that may

be delivered to the Purchaser‟s stores. The Supplier shall be required to accept

responsibility for the advice given in so far as these arrangements may have a bearing on

the behavior of the equipment in subsequent service.

12.1 Hazardous substances

The Supplier shall submit safety data sheets for all hazardous substances used with the

equipment. The Supplier shall give an assurance that there are no other substances

classified as hazardous in the equipment supplied. No oil shall be supplied or used at any

stage of manufacture or test without a certificate acceptable to the Purchaser that it has a

PCB content of less than 2 mg/ kg. The Supplier shall accept responsibility for the

disposal of such hazardous substances, should any be found.

The Supplier shall also be responsible for any injuries resulting from hazardous

substances due to non compliance with these requirements.

12.2 SUBMITTALS

13.1 Submittals required with the bid

The following shall be required with each copy of the bid :

o Completed technical data schedule;

o Descriptive literature giving full technical details of equipment offered;

14.2 Outline dimensions drawing for each major component, general arrangement drawing showing component layout and general schematic diagram;

14.3 Type test certificates ( short circuit withstand test and impulse test ) of the offered transformers conducted at CPRI/ or any NABL Accredited laboratory without which tender will be out rightly rejected.

56

1. Sample routine test reports;

Detailed reference list of customers already using equipment offered along with

performance certificates of such equipment, during the last 3 (three) years with

particular emphasis on units of similar design and rating;

1.1 Details of manufacturer‟s quality assurance standards and programme and

ISO

9000 series or equivalent national certification;

1.3 Deviations from this specification. Only deviations approved in writing before award of contract shall be accepted;

List of recommended spare parts and consumable items for five year of operation with prices and spare parts catalogue with price list for future requirements.

38.2 Submittals required after contract award

38.2.1 Programme

Five copies of the programme for production and testing

38.2.2 Technical Particulars

Within 30 days of contract award five bound folders with records of the technical

particulars relating to the equipment. Each folder shall contain the following information:

General description of the equipment and all components, including brochures;

Technical data schedule, with approved revision;

Calculations to substantiate choice of electrical, structural, mechanical component

size/ ratings;

Detailed dimension drawing for all components, general arrangement drawing

showing detailed component layout and detailed schematic and wiring drawings for

all components; along with core-coil assembly drawings, showing details of core

such as grade, thickness, window height, leg centre, diameter, step width, step

thickness and details of windings such as I.D., O.D , thickness , Conductor size, No.

of turns, major and minor insulations, winding height etc.

Detailed loading drawing to enable the Purchaser to design and construct foundations

for the transformer;

Statement drawing attention to all exposed points in the equipment at which copper /

aluminum or aluminum alloy parts are in contact with or in close proximity to other

metals and stating clearly what protection is employed to prevent corrosion at each

point;

Detailed installation and commissioning instructions;

At the final hold point for Purchaser approval prior to delivery of the equipment the

following shall be submitted ;

Inspection and test reports carried out in the manufacturer‟s works;

Operation and maintenance instructions as well as trouble shooting charts. 38.2.3 Operation and Maintenance Instructions

A copy of installation and commissioning instructions and of the operation and

maintenance instructions and trouble shooting charts shall be supplied with each

transformer.

38.3 Drawings 38.3.1 Within 15 days of award of contract, the Supplier shall submit 4 complete sets of

drawings as detailed below describing equipment in details. These drawings would be

duly approved by the Purchaser after due securitization and approval will be

communicated within 15 days of receipt of these drawings. After the drawings are

approved and communicated to the supplier, he would supply ten complete sets of final

drawings.

38.3.2 All detail drawings submitted for approval shall be to scale not less than 1:20. All

important dimensions shall be given and the material of which each part is to be

constructed shall be indicated on the drawings. All documents and drawings shall be

submitted in accordance with the provisions of this specification and shall become the

property of the Purchaser. % All drawings and calculations, submitted to the Purchaser, shall be on international

standard size paper, either A0, A1, A2, A3 or A4. All such drawings and calculations

shall be provided with a contract title block, which shall include the name of the

Purchaser and shall be assigned an unique project drawing number; the contract title

block and project numbering system shall be agreed with the Purchaser.

% Script sizes and thickness of scripts and lines be selected so that if reduced by two stages

the alphanumeric characters and lines are still perfectly legible so as to facilitate

microfilming.

% For presentation of design drawings and circuit documents IEC Publication 617 or

equivalent standards for graphical symbols are to be followed. The drawing approval will

be communicated within 15 days from the receipt of drawings from the Bidder and for

any delay in furnishing the drawings, if delivery period will be delayed, no extension of

delivery time will be granted due to this.

% The following drawings for each item are to be submitted as part of this Contract.

4.5 Out line dimensional drawings of transformers and accessories

4.6 Assembly drawings and weights of main component parts.

4.7 Transportation drawings showing dimensions and weights of each package.

4.8 Drawings giving the weights for foundations each .

4.9 Drawing showing details such as clamping arrangements of core, core assembly showing oil duct section of HT and LT coils with conductor size showing insulation arrangements of windings and their reinforcement to withstand short circuit stresses, in side tank dimensions showing core assembly. Details of core and windings, as enumerated at Cl. No. 33.2.2 of this part of Specification shall be indicated in the above drawings.

4.10 Schematic diagram showing the flow of oil in the cooling system as well as each limb and winding. Longitudinal and cross- sectional views showing the duct sizes, cooling pipe etc. for transformer/ heat exchanger, drawn to scale shall be furnished.

4.11 Large Scale drawings of high and low tension winding of the transformers showing the nature and arrangements of insulation and terminal connection.

19 Name plate drawing showing details as per Cl. 23 of Part-2 of Technical

Specification.

20 Test Reports

39 FASTENERS 39.1 All bolts, studs, screw threads, pipe threads, bolt heads and nuts shall comply with the

appropriate Indian Standards for metric threads, or the technical equivalent.

39.2 Bolts or studs shall not be less than 6 mm in diameter except when used for small wiring

terminals. All nuts and pins shall be adequately locked. 39.3 Wherever possible, bolts shall be fitted in such a manner that in the event of failure of

locking resulting in the nuts working loose and falling off, the bolt will remain in

position. 39.4 All ferrous bolts, nuts and washers placed in outdoor positions shall be of anti-corrosive

materials except high tensile steel bolts and spring washers which shall be electro-

galvanized to service condition stated elsewhere in the Specification. Appropriate

precautions shall be taken to prevent electrolytic action between dissimilar metals where

bolts are used on external horizontal surfaces and where water can collect, methods of

preventing the ingress of moisture to the threads shall be provided. Each bolt or stud

shall project at least one thread but not more than three threads through the nut, except

when otherwise approved for terminal board studs or relay stems. If bolts nuts are

placed so that they are inaccessible by means of ordinary spanners, special spanners

shall be provided. The length of the screwed portion of the bolts shall be such that no

screw thread may form part of a shear place between members. Taper washers shall be

provided where necessary. Protective washers of suitable material shall be provided

front and back on the securing screws.

40. LABELS

All apparatus shall be clearly labelled indicating, where necessary, its purpose and 40.1 service positions. The material of all labels and plates, their dimensions, legend and the

method of printing shall be subject to approval of the Purchaser. The surfaces of all

labels and plates shall have a mat or satin finish to avoid dazzle from reflected light.

Colours shall be permanent and free from fading. Labels mounted on black surfaces

shall have white lettering. Danger plates shall have white lettering on a red background.

All labels and plates for outdoor use shall be of in-corrodible material. Where the use of

enameled iron plates is approved, the whole surface including the back and edges, shall

be properly covered and resistant to corrosion. They shall be engraved in English. Name

plates shall be white with black engraved lettering and shall carry all the applicable

information specified in the applicable items of the Standards. No scratching,

corrections or changes will be allowed on name plates.

40.2 Name plates shall be provided of white background with black engraved lettering

carrying all the applicable information specified in the standards and other details as

required by the Purchaser. The name plate inscription and the size and lettering shall be

submitted to the Purchaser for approval.

41. PROFORMA FOR STAGE INSPECTION OF DISTRIBUTION TRANSFORMERS

(A) GENERAL INFORMATION:

1. Name of Firm :

2. Order No and Date :

3. Rating –wise quantity offered :

4. Details of offer

(a) Rating

(b) Quantity

(c) Serial Numbers

5. Details of last stage inspected lot :

(a) Total quantity inspected

(b) Serial Numbers

(c) Date of stage inspection

(d) Quantity offered for final inspection of

8. (A) Inspection of BEE 3 Star Level/ Embossing / Punching requirement: whether satisfies the Specification:

deviation if any to be mentioned: 6

(B) AVAILABILITY OF MATERIAL FOR OFFERED QUANTITY:

Details to be filled in

(C) POSITION OF MANUFACTURING STAGE OF THE OFFERED

QUANTITY :

(a) Complete tanked assembly

(b) Core and coil assembly ready 61

9. Core assembled

10. Coils ready for assembly

9.1 HV Coils

9.2 LV Coils

NOTE:

10 A quantity if more than 100 no‟s shall not be entertained for stage inspection

11 The stage inspection shall be carried out in case:-

10.1 At Least 25% quantity offered has been tanked and

10.2 Core coil assembly of further at least 30% of the quantity offered has been completed.

10.3 Quantity offered for stage inspection should be offered for final inspection within 15 days from the date of

issuance of clearance for stage inspection, otherwise stage inspection already cleared shall be liable for

cancellation.

Sl.No Particulars As Offered As observed Deviation and Remarks

D INSPECTION OF CORE 11. Core material

11.1

Manufacturer's Characteristic Certificate in respect of grade of lamination used. (Please furnish test certificate)

11.2 Remarks regarding Rusting and smoothness of core

11.3

Whether laminations used for top and bottom yoke are in one piece.

12. Core Construction: 1 No of steps 2 Dimension of Steps

Step No. 1 2 3 4 5 6 7 8 9 10 11 12

As Offered

W mm

T mm

As found

W mm

T mm

3 Core Dia (mm)

4 Total Cross Section area of

core

5 Effective cross Sectional

area of core

6 Clamping arrangement

(i) Channel Size

(ii) Bolt size and No (iii) Tie Rods (iv) Painting (a) Channels (b) Tie Rods ( c) Bolts 7 Whether top yoke is cut for

LV connection

8 If yes, at 7 above, whether Reinforcement is done

9 Size of support Channels provided for Core base and bottom yoke (Single Piece of channels are only acceptable)

10 Thickness of insulation

provided between core base and support channel

11 Core length (leg center to

leg centre) 12 Window height 13 Core height 14

Core weight only (without channel etc.)

(E) INSPECTION OF

WINDING (I)

Winding material

1 Material used for

(a) HV Winding

(b) LV Winding 2 Grade of material for

(a) HV Winding

(b) LV Winding

3 Test certificate of

manufacturer (enclosed copy) for winding material of :

(a) HV (b) LV CONSTRUCTIONAL

(II) DETAILS 1 Size of Cross Sectional

area of conductor for:

(a) HV Winding

(b) LV Winding 2 Type of insulation for

conductor

(a) HV Winding

(b) LV Winding Diameter of wire used for

17.3.8 delta formation (mm) 17.3.9 Diameter of coils

in: a LV Winding 17.3.10 Internal dia (mm) (ii) Outer dia (mm) 17.3.13 HV

Winding Internal

dia (mm)

Outer dia (mm) 17.3.15 Current Density

of winding material uised for HV LV

17.3.16 Whether neutral

formation on top 17.3.17 HV Coils/ Phase a) Number b) Turns/ coil c) Total turns 8 LV Coils/ Phase

a) Number b) Turns/coil c) Total turns 9 Method of HV Coil Joints

10 Total weight of coils of

(a) HV Winding (Kg)

(b) LV Winding (Kg) F INSULATION

MATERIALS: (I) MATERIAL 1 Craft paper

a) Make b) Thickness (mm) c) Test certificate of

manufacturer (enclosed copy)

2 Press Board

a) Make Thickness

(mm)

Test certificate of manufacturer (enclosed copy)

3 Material used for top and bottom yoke and insulation

II Type and thickness of material used: (mm)

a) Between core and LV b) Spacers c) Interlayer d) Between HV &

LV winding e) Between phases f) End insulation

G CLEARANCES 21 Related to core and

winding 22.1 LV to Core (Radial)

22.2 Between HV and

LV (Radial) 22.3 (i) Phase to phase

between HV Conductor

Whether two Nos Press Board each of minimum 1 mm ;thick provided to cover the tie rods

22.4 Thickness of locking spacers between LV coils

(mm) 5 Axial wedges between

HV and LV coils / phase (Nos)

6 No. of radial spacers per phase between HV coils

7 Size of duct between LV

and HV winding (mm) (II) Between core-coil

assembly and tank: (mm)

1 Between winding and body a) Tank lengthwise

b) Tank breadth wise

2 Clearance between top

cover and top yoke upto 100 KVA and between top cover and top most live part of tap changing switch for 200 KVA and above.

H TANK 1 Constructional details:

1) Rectangular shape

65

2) Thickness of side wall (mm)

3) Thickness of top and bottom place (mm)

4) Provision of slopping top cover towards HV bushing 5) Tank internal dimensions(mm) (a) Length

(b) Breadt

h ( c)

Height

(i) On LV side

On LV side (II) General Details

1) Inside painted by varnish/ oil corrosion resistant paint (please specify which type of coating done)

2) Gasket between top cover and tank (i) Material

(ii) Thickness(mm)

(iii) Joint over laps (mm)

3) Reinforcement of welded angle (Specify size and No. of angle povided) on side walls of tank 4) Provisionof lifting lugs:

a) Numbers

b) Whether lugs of 8 mm thick MS plate provided

c) Whether reinforced by welded plates edge wise below the lug up to re-enforcing angle of the tank done

5) Pulling lug of MS Plate

a) Nos

b) Thickness (mm).

c) Whether provided on breadth side or length side 6) Provision of air release plug

7) Provision of galvanized GI Nuts Bolts with 1 No Plain and 1 No spring washer

8) Deformation of length wise side wall of tank when subject to:

a) Vaccume of (-) 0.7 Kg/sq cm for 30 minutes

b) Pressure of 0.8 Kg/sq cm for 30 minutes

(I) RADIATORS

1. Fin radiators of 1.25 mm thick sheet

a) Dimension of each fin (L x B x T) b) Fins per radiators

c) Total No. of radiators

Verification of manufacturer’s test certificate regarding Heat dissipation (excluding Top and Bottom) in w/sq m

Verification of position of radiator with respect to bushing

(J) CONSERVATOR

1. Dimensions ( L x D) (in mm) 2. Volume (m3)

3.Inside dia of Conservator tank

4. Whether conservator outlet pipe is projected approx.20 mm inside the conservator tank

5Whether arrangement made so that oil does not fall on the active parts

6. Whether die cast metal oil level gauge indicator having three positions at ( -5˚ C, 30˚ C and 98 ˚ C is provided.

7. Whether drain plug and filling hole with cover is provided

8. Inner side of the conservator tank painted with.

(K) BREATHER

1.Whether Die cast Aluminum body breather for silica gel provided

2. Make

3. Capacity

67

34.1 TERMINALS 34.2 Material whether of Brass

Rods/ Tinned Copper HV

LV

34.3 Size (dia in mm)

HV

LV

34.4 Method of Star

connection formed on LV side of 6mm thick (Should use Al./ Cu. Flat bolted/ brazed with crimped lugs on winding alternatively for 63 and 100 KVA rating brazed is done covered with tubular sleeve duly crimped) Please state dimensions of Al/Cu flat or tubular sleeve used (mm)

34.5 Method of Connection of

LV of winding to LV bushing (end od winding should be crimped with lugs(Al/Cu) and bolted with bushing stud)

34.6 Method of Connection of

HV winding to HV bushing (Copper joint should be done by using silver brazing alloy and for Aluminum, brazing rod or with tubular connector crimped at three spots).

34.7 Whether SRB P tube/

insulated paper used for formation of Delta on HV

34.8 Whether Empire sleeves

used on the portion of HV winding joining to HV bushing

34.9 Whether neutral formation

is covered with cotton tape

(M) BUSHING 1 Whether HV bushing

mounted on side walls. 2 Whether sheet metal

pocket used for mounting bushing (pipe are not acceptable)

a) HV b) LV

68

3 Whether arrangement for studs for fitting of HV bushing are in diamond shape ( so that Arcing Horns are placed vertically) 4. Position of mounting of LV bushing

5. Bushing Clearance: (mm) a) LV to Earth

b) HV to Earth

c) Between LV Bushings

d) Between HV Bushings

(N) TANK BASE

CHANNEL/ROLLERS: 36.2 Size of channels(mm)

36.3 Whether channels

welded across the length of the tank

36.4 Size and type of roller

(mm) 37 OIL 38.1 Name of Supplier

38.2 Break down voltage of

oil:(KV)

i) Filled in tanked Transformers

In storage tank ( to be tested by Inspecting Officer).

Supplier's test certificate (Enclosed)

(P) ENGRAVING

/ PUNCHINGS 1. Engaraving of Sl. No and name of firm

i) On bottom of clamping channel of core-coil assembly

ii) On side wall and top cover of tank along with date of dispatch. / Guarantee Period iii) 3 Star Level: Whether contains 3 Star Level with style prescribed by the B.E.E.

o i) MS plate of size 125 x 125 mm welded on width side of stiffener

Following details engraved (as per approved GTP)

69

(a) Serial Number

(b) Name of Firm

( c) Order No. and Date

(d) Rating

(e) Name of Inspecting Officer (f) Designation

(g) Date of dispatch

( R) NAME PLATE DETAILS

Whether Name Plate is as per approved drawing

38.2.2 Colour of Transformer

Tank body with light blue colour

Conservator with

white colour 38.2.3 CHECKING OF

TESTING FACILITIES

(Calibration certificate also to be checked for its validity)

TESTS

No Load Current

No Load Loss

% Impedance

Load Losses

Insulation

Resistance Test

Vector Group Test (phase relationship)

Ratio and Polarity test

relationship

Transformer oil Test (Break down Voltage)

Magnetic Balance

Measurement of winding resistance (HV and LV both)

Induced over voltage

withstand test ( Double voltage and Double frequency)

Separate source

power frequency withstand test at 28 KV for HV and 3 KV for LV (one minute)

Air Pressure/ Oil leakage Test

70

14. Vacuum Test

15. Unbalanced current

test

16. Temperature

rise(Heat Run) test

(U) We have specifically

checked the following and

found the same as per

G.T.P./ deviations

observed as mentioned

against each.

i) Rustlessness of CRGO

laminations used

ii) Core Steps

iii) Core Area

iv) Core Weight

v) Winding cross section

area

a) LV

b) HV

vi) Weight of windings

vii) Clearance between

winding and wall of tank

(mm)

a) Length-wise

b) Breadth- wise

viii) Clearance between

top of yoke top most live

part of tap changer to

tank cover

ix) Details of Neutral

formation

x) Connections to

bushings

a) LV

b) HV

xi) Slope of tank top

xii) Position of mounting

of bushings

COMPANY INSPECTING OFFICER FIRMS

REPRESENTATIVE DATE OF INSPECTION

. 71

GUARANTEED TECHNICAL PARTICULARS FOR 25KVA,11/0.4KV, 3-PHASE STAR RATED DISTRIBUTION TRANSFORMERS

(To be furnished by the Manufacturer) Sl.

No Description As Specified Bidder's Offer 1 Make

2 Name of the Manufacturer

3 Place of Manufacture

3 (a) Type of B.E.E Specified Star Level to be fixed near

Name Plate. BIS ENERGY EFFICIENCY LEVEL-2 & BEE STAR-1

4 Voltage Ratio 11000/433V

5 Rating in KVA 25

6 Core Material used and Grade: CRGO and M3 or Better

a) Flux density 1.5 Tesla (Max.)

b) Over fluxing without saturation (Curve to be

furnished by the Manufacturer in support of his

claim)

7 Maximum temperature rise of:

400C over an ambient of

a) windings by resistance method 500C


b) Oil by thermometer 500C

8 Magnetizing (no-load) current

at: a) 90% Voltage

b) 100% Voltage 3% (Max.)

c) 112.5% Voltage 6% (Max.) 9 Core loss in watts:

a) Normal voltage

b) Maximum voltage

(a) Resistance of windings at 200C (with 5%

tolerance) HV Winding (ohms)

LV Winding (ohms)

(b) Full load losses (watts) at 75

0C

12 Total losses at 100% load at 75 0 C 695 Watts (Max.)


14 Current density used for : (Ampere/ Sq mm)

a) HV Winding 1.6(Max.)

b) LV Winding 1.6(Max.)

15 Clearances : (mm)

a) Core and LV

b) LV and HV

c) HV Phase to Phase

78

d) End insulation clearance to earth

e) Any point of winding to tank

16 Efficiency at 75 0 C:

a) Unity P. F. and

b) 0.8 P.F

1) 125% load

2) 100% load

3) 75% load

4) 50% load

5) 25% load

17 Regulation at:

a) Unity P.F.

b) 0.8 P.F. at 750C

18 % Impedance at 750C

4.5+10%(No negative

tolerance)

19 Separate Source Voltage withstand Test:

(I) HV 28kV/50 HZ for 1 minute Yes

(ii) LV 3kV/50 HZ for 1 minute Yes

22KV for HV winding by

20 applying 0.866 KV on LV

Induced Over Voltage withstand Test (Double at 100Hz for the duration

Voltage and Double frequency for 1 minute) of 1 minute.

21 Impulse test HV-95KV peak, LV- NA

22 Mass of : (kg)

a) Core lamination (minimum)

b) Windings (minimum)

c) Tank and fittings

d) Oil

e) Oil quantity (minimum) (litre)

f) Total weight

23 Oil Data:

1. Quantity for first filling (minimum) (litre)

2. Grade of oil used

3. Maker's name

4. BDV at the time of filling (kV)

24 Transformer:

1) Overall length x breadth x height (mmx mmx

mm)

2) Tank length x breadth x height

3) Thickness of plates for

a) Side plate (min) 3.15mm

b) Top and bottom plate (min) 5mm

4) Conservator Dimensions.

25 Radiation

1) Heat dissipation by tank walls excluding top and

bottom

2) Heat dissipation by cooling tube.

3) Diameter and thickness of cooling tube.

4) Whether calculation sheet for selecting cooling

area to ensure that the transformer is capable of

giving continuous rated output without exceeding

temperature rise is enclosed.

26 Inter layer insulation provided in design for:

1) Top and bottom layer Epoxy Dotted Kraft Paper

2) In between all layer Epoxy Dotted Kraft Paper

3) Details of end insulation. Press Board

4) Whether wedges are provided at 50% turns of

the HV coil

27 Insulation materials provided

a) For conductors

(1) HV DPC

(2) LV DPC

b) For Core Carlite

28 Material and Size of the wire used.

1) HV Dia (mm) (SWG)

2) LV

a) Strip size

b) No. of Conductors in parallel

c) Total area of cross section (sq mm)

29 Whether the name plate gives all particulars as

required in Tender

Yes

30 Particulars of bushings HV/LV

1) Maker's name

2) Type IS-3347/ IS-2099/ IS- 7421

3) Rating as per IS

4) Dry power frequency voltage withstand test HV-28KV, LV-3KV

5) Wet power frequency voltage withstand test HV-28KV, LV-3KV

Note:

The following shall be specifically confirmed:

Whether the offer conforms to the limits of

1) impedance mentioned in the specification.


2) temperature rise mentioned in the specification.

Whether the losses of the transformers offered are

3) within the limits specified.

Whether the transformer offered is already type

4) tested for the design and test reports enclosed.

GUARANTEED TECHNICAL PARTICULARS FOR 16 KVA,11/0.4KV, 3-PHASE STAR RATED DISTRIBUTION TRANSFORMERS








5 Rating in KVA 16





claim)






9 Magnetizing (no-load) current

at: a) 90% Voltage


c) 112.5% Voltage 6% (Max.) 10

Core loss in watts:

a) Normal voltage

b) Maximum voltage

(c) Resistance of windings at 200C (with 5%


LV Winding (ohms)

(d) Full load losses (watts) at 75

0C







a) Core and LV

b) LV and HV


78




a) Unity P. F. and

b) 0.8 P.F

1) 125% load

2) 100% load

3) 75% load

4) 50% load

5) 25% load

17 Regulation at:

a) Unity P.F.

b) 0.8 P.F. at 750C


4.5+10%(No negative

tolerance)









22 Mass of : (kg)




d) Oil


f) Total weight

23 Oil Data:



3. Maker's name


24 Transformer:


mm)






25 Radiation


bottom












the HV coil


a) For conductors

(1) HV DPC

(2) LV DPC

b) For Core Carlite



2) LV

a) Strip size




required in Tender

Yes


1) Maker's name

2) Type IS-3347/ IS-2099/ IS- 7421

3) Rating as per IS



Note:


















5 Rating in KVA 63





claim)






10

Magnetizing (no-load) current at: a) 90% Voltage


c) 112.5% Voltage 6% (Max.) 11

Core loss in watts:

a) Normal voltage

b) Maximum voltage

(e) Resistance of windings at 200C (with 5%


LV Winding (ohms)

(f) Full load losses (watts) at 75

0C







a) Core and LV

b) LV and HV


78




a) Unity P. F. and

b) 0.8 P.F

1) 125% load

2) 100% load

3) 75% load

4) 50% load

5) 25% load

17 Regulation at:

a) Unity P.F.

b) 0.8 P.F. at 750C


4.5+10%(No negative

tolerance)









22 Mass of : (kg)




d) Oil


f) Total weight

23 Oil Data:



3. Maker's name


24 Transformer:


mm)






25 Radiation


bottom












the HV coil


a) For conductors

(1) HV DPC

(2) LV DPC

b) For Core Carlite



2) LV

a) Strip size




required in Tender

Yes


1) Maker's name

2) Type IS-3347/ IS-2099/ IS- 7421

3) Rating as per IS



Note:












No Description As Specified Bidder's Offer 10

Make






5 Rating in KVA 100





claim)






11

Magnetizing (no-load) current at: a) 90% Voltage


c) 112.5% Voltage 6% (Max.) 12

Core loss in watts:

a) Normal voltage

b) Maximum voltage

(g) Resistance of windings at 200C (with 5%


LV Winding (ohms)

(h) Full load losses (watts) at 75

0C







a) Core and LV

b) LV and HV


78




a) Unity P. F. and

b) 0.8 P.F

1) 125% load

2) 100% load

3) 75% load

4) 50% load

5) 25% load

17 Regulation at:

a) Unity P.F.

b) 0.8 P.F. at 750C


4.5+10%(No negative

tolerance)









22 Mass of : (kg)




d) Oil


f) Total weight

23 Oil Data:



3. Maker's name


24 Transformer:


mm)






25 Radiation


bottom












the HV coil


a) For conductors

(1) HV DPC

(2) LV DPC

b) For Core Carlite



2) LV

a) Strip size




required in Tender

Yes


1) Maker's name

2) Type IS-3347/ IS-2099/ IS- 7421

3) Rating as per IS



Note:










14.0 FASTENERS: Bolts, Nuts & Washers

22. All bolts and nuts shall conform to IS-6639 – 1972. All bolts and nuts shall be

galvanized. All bolts and nuts shall have hexagonal heads, the heads being

truly concentric, and square with the shank, which must be perfectly straight.

b) Bolts upto M16 and having length upto ten times the diameter of the bolt

should be manufactured by cold forging and thread rolling process to obtain

good and reliable mechanical properties and effective dimensional control.

The shear strength of bolt for 5.6 grade should be 310 Mpa minimum as per

IS-12427. Bolts should be provided with washer face in accordance with IS-

1363 Part-I to ensure proper bearing.

c) Fully threaded bolts shall not be used. The length of the bolt shall be such

that the threaded portion shall not extend into the place of contact of the

component parts.

d) All bolts shall be threaded to take the full depth of the nuts and threaded

enough to permit the firm gripping of the component parts but not further. It

shall be ensured that the threaded portion of the bolt protrudes not less than 3

mm and not more than 8 mm when fully tightened. All nuts shall fit and be

tight to the point where shank of the bolt connects to the head.

e) Flat washers and spring washers shall be provided wherever necessary and

shall be of positive lock type. Spring washers shall be electro-galvanized. The

thickness of washers shall conform to IS-2016-1967.

f) The bidder shall furnish bolt schedules giving thickness of components

connected, the nut and the washer and the length of shank and the threaded

portion of the bolts and size of holes and any other special details of this

nature.

g) To obviate bending stress in bolt, it shall not connect aggregate thickness

more than three time its diameter.

h) Bolts at the joints shall be so staggered that nuts may be tightened with

spanners without fouling.

i) Fasteners of grade higher than 8.8 are not to be used and minimum grade for

bolts shall be 5.6.

GENERAL TECHNICAL SPECIFICATION OF MATERIALS

A. TECHNICAL SPECIFICATION FOR ALL ALUMINIUM ALLOY

CONDUCTOR (AAAC)

1. SCOPE

This specification covers design, Engineering, Manufacture, Testing, Inspection

before dispatch, forwarding, packing, transportation to sites, Insurance (both during

transit & storage ), storage, erection, supervision testing & commissioning of all

sizes of All Aluminium Alloy Conductors of the Aluminium – magnesium- silicon

type for use in the distribution overhead power lines of SOUTHCO ,Orissa.

The material offered shall have been successfully type testes and the design shall

have been satisfactory operation for a period not less than two years on the date of

bid opening. Compliance shall be demonstrated by submitting with the bid, (i)

authenticated copies of the type test reports and (ii) performance certificates from

the users.

The scope of supply includes the provision of type test, Rates of type tests shall be

given in the appropriate price schedule of the bidding document and will be

considered for evaluation. The Purchaser reserves the right to waive type tests as

indicated in the section on Quality Assurance, Inspection and Testing in the

specification.

The Aluminium Alloy Conductor shall conform in all respects to highest standards

of engineering, design, workmanship, this specification and the latest revisions of

relevant standards at the time of offer and the Purchaser shall have the power to

reject any work or materials, which, in his judgment, is not in full accordance

therewith.

STANDARDS

Except where modified by the specification, the Aluminium Alloy Conductor shall

be designed, manufactured and tested in accordance with latest editions of the

following standards.

IEC :1089 Round wire concentric lay overhead

electrical standard conductors

IS 398 Aluminium Alloy Stranded Conductors

IS 9997 Aluminium Alloy redraw rods for

electrical purposes

IEC 502 : 1994 Extruded solid dielectric insulated power

cables for rated voltages 1.0 KV up to 30

KV

IEC 104 Aluminium Magnesium Silicon alloy wire

for overhead line conductors

IS 1778 Reels and drums of bare conductor.

BS : 6485-1971 PVC covered conductors for overhead

power lines.

This list is not to be considered exhaustive and reference to a particular standard or

recommendation in this specification does not relieve the contractor of the necessity of

providing the goods complying with other relevant standards or recommendations.

3. GENERAL

The wires shall be of heat treated Aluminium, magnesium silicon alloy containing

approximately silcon-0.5 to 0.9 %. magnesium-0.6 % to 0.9%,Fe-0.5% (maximum) ,

Copper- 0.1% (max ), mn- 0.03% , Cr-0.03%, Zn-0.1%, B-0.06%, and having the

mechanical and electrical properties specified in the table and be smooth and free

from all imperfections, such as, spills, splits and scratches.

Neutral grease shall be applied between the layers of wires. The drop point

temperature of the grease shall not be less than 1200 ˚C.

3.1 Mechanical and Electrical Characteristics of Aluminium Alloy Wires used

in the Construction of Stranded Aluminium Alloy Conductors

Nominal

Diameter

Minimu

m

Diameter

Max.

Diameter

Cross

Sectional

Area

Mass Minimum Breaking

Load

Maximu

m

Resistan

ce at 200

C

Before

stranding

After

stranding

mm mm mm mm2 Kg/k

m

KN KN ohms/km

4.26 4.22 4.30 14.25 38.48 4.40 4.18 2.345

Maximum resistance values given in column 8 have been calculated from the

maximum values of the resistively as specified and the cross sectional area based on

the minimum diameter. The minimum breaking load is calculated on nominal diameter

at ultimate tensile strength of 0.309 KN / mm² for wire before stranding and 95% of the

ultimate tensile strength after stranding.

4. PHYSICAL CONSTANTS FOR ALUMINIUM ALLOY

WIRES

4.1 Resistively :

For the purpose of this specification, the standard value of resistively of Aluminium

alloy wire which shall be used for calculation is to be taken as 0.0325 ohm mm² /m

at 200 ˚C. the maximum value of resistively of any single wire shall not , however,

exceed 0.0328 ohm. mm²/m at 20˚ C.

4.2 Density :

At a temperature of 200 ˚C, the density of aluminium alloy wire is to be taken as

2700 kg/m3.

4.3 Temperature Coefficient of Linear Expansion :

The temperature coefficient of linear expansion of aluminium alloy wire is to be

taken as

(23 x10-6

) per ˚C .

4.4 Constant – Mass Temperature Coefficient

At a Temperature of 200 ˚C, the constant – mass temperature coefficient of

resistance of Aluminium alloy wires, measured between two potential points

rigidly fixed to the wire, is taken as 0.00360/˚C

5. STANDARD SIZES

5.1 Nominal Sizes of Wires

The Aluminium alloy wires for standard constructions covered by this specification

shall have the diameters as specified in the table and a tolerance of ±1% shall be

permitted on the nominal diameter.

5.2 Standard Conductors

The sizes, resistance and masses (excluding the mass of grease ) of stranded

Aluminium alloy conductors shall be as given in table.

Sl. No. Actual

Area

Strandin

g and

Wire

Dia

Approx.

Overall

Dia

Approx.

Mass

Calculated

Maximum

Resistance

at 200 C

Approx

Calculated

Breaking

Load

1 2 3 4 5 6 7

mm² mm mm Kg/Km Ohm/Km KN

1 100 7/4.26 12.78 272.86 0.3390 29.26

5.3.1 Increase in Length due to Stranding When straightened out, each wire in any particular layer of a stranded conductor,

except the central wire, is longer than the stranded conductor by an amount

depending on the lay ratio of that layer.

5.3.2 Resistance and Mass of Conductor

The resistance of any length of stranded conductor is the resistance of the same

length of any one wire multiplied by a constant as set out in the table below.

The mass of each wire in any particular layer of the stranded conductor, except the

central wire, will be greater than that of an equal length of straight wire by an

amount depending on the lay ratio of that layer. The total mass of any length of an

Aluminium stranded conductor is, therefore, obtained by multiplying the mass of an

equal length of straight wire by an appropriate constant as mentioned below. In

calculating the stranding constants as mentioned in the table below, the mean lay

ratio, that is the arithmetic mean of the relevant minimum and maximum values in

table for lay ratio has been assumed for each layer.

5.3.3 Calculated Breaking Load of Conductor

For a conductor containing not more than 37 wires, 95% of the sum of strength of

the individual wires calculated from the values of the minimum breaking load given

in this specification.

For a conductor containing more than 37 wires, 90% of the sum of the strengths of

the individual wire calculated from the values of the minimum breaking load given

in this specification.

5.3.4 Calculated Area and Maximum Resistance of Conductor

The actual area of a stranded conductor has been taken as the sum of the cross-

sectional areas of the individual wires of nominal diameter.

Maximum resistance values of stranded conductor have been calculated on the basis

of maximum resistivity and the cross-sectional area based on the minimum diameter

of wires.

5.4 Stranding Constants

Number of Wires in

Conductor

Stranding Constants

Mass Electrical Resistance

7 7.091 0.1447

6. JOINTS IN WIRES

6.1 Conductor containing seven wires

There shall be no joint in any wire of a stranded conductor containing seven wires,

except those made in the base rod or wire before final drawing.

6.2 Conductors containing more than seven wires

In stranded conductors containing more than seven wires, joints in individual wires

are permitted in any layer except the outermost layer ( in addition to those made in

the base rod or wire before final drawing ) but no two such joints shall be less than

15 m apart in the complete stranded conductor. Such joints shall be made by cold

pressure butt welding. They are not required to fulfill the mechanical requirements

for unjointed wires.

7. STRANDING

The wire used in the construction of a stranded conductor shall, before and after

stranding, satisfy all the relevant requirements of this standard.

The lay ratio of the different layers shall be within the limits given in the table for

lay ratio.

In all constructions, the successive layers shall have opposite directions of lay, the

outermost layer being righ-handed. The wires in each layer shall be evenly and

closely stranded.

In Aluminium alloy stranded conductors having multiple layers of wires, the lay

ratio of any layer shall not be greater than the lay ratio of the layer immediately

beneath it.

7.1 Lay Ratios for Aluminium Alloy Stranded

Conductors

Number of Wires in Conductor Lay Ratios

7 Min-10 Max-14

NOTE: For the purpose of calculation the mean lay ratio shall be taken as the

arithmetic mean of the relevant minimum and maximum values given in this table.

8. LENGTHS AND VARIATIONS IN LENGTHS :

Unless otherwise agreed between the Employer and the Contractor, stranded

aluminium alloy conductors shall be supplied in the manufacturer’s usual

production lengths to be indicated in the bid Schedule. The Employer reserves

the right to specify particular lengths of conductor such that certain drum

lengths will be shorter than others. There will in both cases be a permitted

variation of –0 + 5% in the length of any one conductor length.

9. TESTS

9.1 Type Tests

The following tests shall be carried out as per relevant ISS once on samples of

completed line conductor during each production run of up to 500 kms of the

conductor from each manufacturing facility.

9.1.1 Ultimate Tensile Strength Test

This test is intended to confirm not only the breaking strength of the finished

conductor but also that the conductor has been uniformly stranded.

A conductor sample of minimum 5 m length fitted with compression dead end clamps

at either end shall be mounted in a suitable tensile test machine. Circles perpendicular

to the axis of the conductor shall be marked at two places on its surface. Tension on

the conductor sample shall be increased at a steady rate upto 50% of the minimum

UTS specified and held for one minute. The circles drawn shall not be distorted due to

relative movement of the individual strands. Thereafter the load shall be increased at a

steady rate to the specified minimum UTS and held at that load for one minute. The

conductor sample shall not fail during this period. The applied load shall then be

increased until the failing load is reached and the value recorded.

9.1.2 D.C Resistance Test

On a conductor sample of minimum 5 m length two contact clamps shall be fitted

with a pre-determined bolt torque. The resistance between the clamps shall be

measured using a Kelvin double bridge by initially placing the clamps at zero

separation and subsequently one meter apart. The test shall be repeated at least five

times and the average value recorded. The value obtained shall be corrected to the

value at 200 C, which shall conform to the requirements of this specification.

9.2 Routine Tests

Measurement of Physical Dimensions :

The samples should meet the desired dimensional requirements before conducting

following Routine Tests as per relevant ISS.

9.2.1 Selection of Test Samples

Samples for the tests specified in this specification shall be taken by the manufacturer

before stranding, from not less than 10% of the individual lengths of aluminium alloy

wire included in any one final heat-treatment batch and which will be included in any

one consignment of the stranded conductors to be supplied.

Alternatively, if desired by SOUTHCO at the time of placing an order, that the tests

be made in the presence of his representative, samples of wire shall be taken from

length of stranded conductor.

Samples shall then be obtained by cutting 1.2 meters from the outer end of the

finished conductor from not more than 10% of the finished reels or drums.

Tests for electrical and mechanical properties of Aluminium alloy wire shall

ordinarily be made before stranding since wires unlaid from conductors may have

different physical properties from those of the wire prior to stranding because of the

deformation brought about by stranding and by straightening for test.

Spools offered for inspection shall be divided into equal lots, the number of lots being

equal to the number of samples to be selected, a fraction of a lot being counted as s

complete lot. One sample spool shall be selected at random from each lot.

The following test shall be carried out once on samples of completed line conductor

during each production run of up to 500 kms of the conductor from each

manufacturing facility.

9.2.2 Breaking Load Test

The breaking load of one specimen, cut from each of the samples taken shall be

determined by means of a suitable tensile testing machine. The load shall be applied

gradually and the rate of separation of the jaws of the testing machine shall be not less

than 25 mm / min and not greater than 100mm /min.

9.2.3 Elongation Test

The elongation of one specimen cut from each of the samples taken shall be

determined as follows:

The specimen shall be straightened by hand and an original gauge length of 200 mm

shall be marked on the wire. A tensile load shall be applied as described above and

the elongation shall be measured after the fractured ends have been fitted together. If

the fracture occurs outside the gauge marks, or within 25 mm of either mark, and the

required elongation is not obtained, the test shall be disregarded and another test

should be made.

When tested before and after stranding, the elongation shall not be less than 4% on a

gauge length of 200 mm.

9.2.4 D.C Resistance Test

The electrical resistance test of one specimen cut from each of the samples taken shall

be measured at ambient temperature. The measured resistance shall be corrected to

the value at 20 ˚C by means of the formula :

R20 = RT [1/{1+α (T-20)}]

where ,

R20 = resistance corrected at 20˚ C

RT = resistance measured T˚ C

α= constant – mass temperature coefficient of resistance, 0.0036,

and T = ambient temperature during measurement.

The resistance corrected at 20 ˚ C shall not be more than the maximum values

specified.

9.2.5 Chemical Analysis of Aluminium Alloy

Samples taken from the alloy coils / strands shall be chemically / spectrographically

analyzed. The results shall conform to the requirements stated in this specification.

The contractor shall make available material analyses, control documents and

certificates from each batch as and when required by the Purchaser.

Test should be conducted at the independent test house by the purchaser in the case of

absence Of facility at manufacturer. However the cost of such testing shall be borne

by the manufacturer.

9.2.6 Dimensional and Lay Length Check

The individual strands of the conductors shall be dimensionally checked and the lay

lengths checked to ensure that they conform to the requirements of this specification.

Ten percent drums from each lot shall be rewound in the presence of the Purchaser or

his representative to allow visual checking of the conductor for joints, scratches or

other surface imperfections and to ensure that the conductor generally conforms to the

requirements this specification. The length of conductor wound on the drum shall be

re-measured by means of an approved counter / meter during the rewinding process.

9.2.7 Visual and dimensional Checks on the Conductor Drums.

The drums shall be visually and dimensionally checked to ensure that they conform to

the requirements of this specification and of IS 1778: Specification for reels and

drums of bare conductors. For wooden drums, a suitable barrel batten strength test

procedure is required. The Bidder shall state in his bid the tests to be carried out on

the drums and shall include those tests in the Quality Assurance Programme.

9.2.8 Acceptance Tests : All tests required to confirm enclosed Guaranteed Technical

Particulars (GTP) requirements of this specification needs to be conducted as

Acceptance Tests.

10. REJECTION AND RETESTS

10.1 Type Tests

Should the conductor fail any of the type tests specified above, the Purchaser will not

accept any conductor manufactured from the material, nor conductor made by the

manufacturing methods used for the conductor which failed the test.

The manufacturer shall propose suitable modifications to his materials and techniques

in order that he can produce conductor which will satisfactorily pass the type test

requirements.

10.2 Routine Tests

.

Should any one of the test pieces first selected fail the requirements of the tests, two

further samples from the same batch shall be selected for testings, one of which shall

be from the length from which the original test sample was taken unless that length

has been withdrawn by the manufacturer.

Should the test pieces from both these additional samples satisfy the requirements of

the tests, the batch represented by these samples shall be deemed to comply with the

standard. Should the test pieces from either of the two additional samples fail, the

batch represented shall be deemed not to comply with the standard.

If checks on individual strand diameters, conductor lay lengths and conductor surface

condition indicate non-compliance with the requirements of the specification, the

particular drum will be rejected. Inspection will then be carried out on two further

drums within the same batch. If the conductor on either of the drums is non-

complaint, the complete batch will be rejected.

10.3 Delivery Extension due to Rejection of Conductor

The rejection of conductor due to its failure to pass either type or routine tests shall

not permit the Contractor to apply for any extension to the time period within which

he has contracted to complete the project.

Description Requirement Details

furnished by

the bidder 55 Sq.mm

1. Stranding and diameter of Aluminum

Alloy Strand

7/3.15 mm

2. Over all diameter of conductor in mm 9.45

3. Standard nominal Aluminium Alloy

area

in Sq.mm

55

4. Calculated Aluminium alloy area in

Sq.mm

54.55

5. Minimum ultimate tensile strength of

Aluminium Wire strand in Kg/mm2

31.57

Kgs./Sq.mm

6. Guaranteed ultimate tensile strength of

conductor in Kg/mm2

1634 Kgs

7. Minimum breaking load in Kg. For

a) AluminiumAlloy Strand

b)Aluminium Alloy Conductor

2.29 KN

16.03 KN

8. Maximum working tension of

conductor

70% of UTS

9. Weight in Kg. Per KM of Aluminium

Alloy conductor

149.20 Kgs

approx.

10. Resistance in Ohm per KM at 20 C 0.621 max.

11. a) Continuous maximum current

rating

of conductor in still air at 450C ambient

temperature (A)

b) Temperature rise for the above current

(deg.C)

173 Amps

300C

12. Modulus of Elasticity of Aluminium

Alloy conductor Kg/Sq.mm

0.6320X106

13. Co-efficient of linear expansion per

degree centigrade for

a) Aluminium Alloy Strand/0C

b) Alloy conductor/0C

23X10-6

23X10-6

14. Standard length of each piece in KM 1.70 and above

15. Dimension of the reel in Cms. 135X50X71

16. Gross weight of the reel including

weight of the conductor Kg.

Max. 1500

17. Standard according to which the

conductor will be manufactured and

tested

IS : 398 (Part-4)

– 1994

18. Other particulars

TECHNICAL SPECIFICATION OF G.I EARTH PIPE

1. SCOPE: The Specification provides for the manufacture, testing at manufacturer‟s

works before supply of G.I Earth Pipes.

2. STANDARDS: The G.I Earth Pipes shall confirm in all respects to the Indian Standard

IS-1239 (Part-I)/ 1990.

3. GENERAL REQUIREMENTS: The G.I Earth Pipes shall be 40mm bore and 3.25mm

wall thickness as per IS-1239 (Part-I), 1990 length 2.5 meters as per specification.

4. TESTS AND TEST CERTIFICATES: All the tests shall be carried out as per the

IS-1239 (Part-i), 1990.

5. MARKING: The G.I Earth Pipes shall be legibly and indelibly marked as mentioned.

a). Name of Trademark of the manufacture.

b). Month and Year of manufacture and

c). Country of manufacture.

Sl. No Description Parameters Expected Value

1 Makers Name

2. Standard to which the earthing pipe confirm REC Standard-J 2

3. Size of the pipe 40 mm nominal Bore as per

ISS(Medium

gauge)1239/Part-I/1979

4. Length of the pipe 2.5mtrs

5. Thickness of the pipe 3.25mm

6. Outer diameter of the pipe 48.8 mm maximum

47.9 mm minimum

7. Standard for processing of Galvanising and testing for

uniformity and mass of Zinc coating of the pipe

IS:2620/1985 IS:2629/1986

SI:6745/1972

8. G.I Clamp for earthing pipe 40mmX6mm

9. G.I Bolts Size 5/8”X1 &1/2”

(K). TECHNICAL SPECIFICATION OF ALUMINIUM BINDING WIRE:

1.0 SCOPE:

Scope covers manufacture, testing and supply of 3.53 mm dia Aluminium Binding Wire as per IS

398.

2.0 MATERIALS:

The material comprising the wire shall have the following chemical composition: Aluminium 99.5%

minimum Copper, silicon and iron 0.5% maximum The surface of the wire shall be smooth and free

from all irregularities and imperfections. Its cross sections shall closely approximate that of true

circle.

Diameter of wire Cross sectional area

of nominal dia. Wires

(mm²)

Weight of

wire

kg/km

Breaking

Load

(kN) Minimum Nominal Maximum

3.15 3.53 3.55 9.787 26.45 1.57

Inspection and Tests

The following routine checks and tests shall be carried out on 10% of the coils of aluminium binding

wire. If anyone sample fails to pass any one of the test nominated for that wire, then samples shall be

taken from every coil in the consignment and any coil from which a sample proves defective shall be

rejected. On no account shall any rejected material be presented for test again unless with the written

approval of, and under conditions determined by the Purchaser.

Physical properties

The surface of the finished wires shall be checked to ensure that it is smooth , free from all

irregularities, imperfections and inclusions and that its cross section approximates closely that of true

circle. The wire shall be checked to ensure that its diameter and weight are within the values given in

the table above for characteristic of a aluminium binding wire.

Ultimate tensile strength

When tested on a standard tensile testing machine, the value obtained for the ultimate tensile stress

shall not be less than 1.57kN

Wrapping test

The wire shall withstand one cycle of a wrapping test as follows: The wire shall be closely wrapped

round a wire of its own diameter form a close helix of eight turns. Six turns shall then be unwrapped

and again closely rewrapped in the same direction as the first wrapping. The wire shall not break or

crack when subjected to this test.

Packing & Delivery

The aluminum binding wire shall be delivered in 30m coils, with a permitted tolerance of

+5%.Random or non standard lengths shall not be permitted. Each coil shall be adequately guarded

against damage due to transportation and handling and shall have an outer layer of tightly wound

polythene tape or be contained in a suitable, transparent plastic bag. The internal diameter of the

wound coil shall not be such as to result in a permanent set in the conductor.

The coils shall be contained in non returnable wooden cases, with a gross weight not in excess of 300

kg. The number of coils contained shall be marked on the outside of each case.

GUARANTEED TECHNICAL PARTICULARS

Sl.No. Description Bidder’s offer

1 Manufacturer Address

2 Indian Standard No. IS 398 (Part-4) 1994

3 Material of Binding Wire

4 Dia. Of Wire

5 Maximum D.C. resistance at 20 degree centigrade

6 Individual Aluminium Alloy Strands

A Tensile breaking stress

B Elongation on 200 mm length in breaking

7 Particulars of Raw Materials

7.1 Aluminium

a) Minimum Purity of aluminimum

7.2 Aluminium Alloy

a) Aluminium redraw rod conforming to element

(a) Si

(b) Cu

( c) Other Element (If any)

8 Linear mass of Wire

9 Modulus of Elasticity

10 Coefficent of Linear Expansion (per deg. Cent.)

DESIGN OF SPIKES

1. G.I. Plate 325 mm x 325 mm x 6 mm ( Wt. in Kg.= 5 kg.)

2. (i) Wt. of 2 No. plate =2 x 5 Kg =10 Kg.

(ii) Wt. of 40 mm x 4 mm thickness x 3 mtr length GI Pile= 85 Kg.

(iii) Wt of support pipe 50 mm x 4.5 mm x 100 mm = 5 Kg.

________

Total = 100 Kg

CONCRETING OF PSC POLES

N.B:- (1) After welding of channel and angles, the mass concreting has to be

done with minimum coverage of 75 mm.

(2) Concreting should be 1 : 2 : 4 (mix).

(3) Height of cooping above the ground should be 750 mm in cultivated land.

AB Cable Accessories

EYE HOOK DETAILS OF (AB Cable)

(One bolt in case of Dead End clamp & two bolts for fitting stay)

DEAD END BACK CLAMP

Suspension Back Clamp

Approx. wt.of 4.5 Kg.

Transformer Foundation for 250 KVA and above

ELEVATION

PLAN

DRAWINGS

Documents

1. GENERAL 1.1 GUARANTEED TECHNICAL PARTICULARS 1.2 … · 2.0.1 Road Crossings:-At all road crossings, the poles shall be fitted with strain type insulators. The ground clearance