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Agenda for the 76th
Meeting of PCSC scheduled to be held on 26th
July, 2018 Page 1
SOUTHERN REGIONAL POWER COMMITTEE BENGALURU
Agenda for the 76th Meeting of Protection Coordination Sub-Committee of SRPC to be held on 26th July, 2018
1. Introduction
2. Confirmation of Minutes of last PCSC meeting
Confirmation of minutes of 75th Protection Coordination Sub-Committee meeting held on 28.06.2018.
3. Grid Occurrences
3.1 Grid Disturbances (GD), Grid Incidences (GI), and trippings due to failure of Auto-
reclosing (A/R), and mal-operation of PLCC equipment that occurred during the period June, 2018 given at Annexure-I would be discussed in the PCSC meeting.
Constituents are requested to furnish the following information in respect of the above grid occurrences to have fruitful discussions.
(a) Single line diagram of the station with switching devices, CT, PT and relay details. (b) Cause of the tripping & Remedial Action taken (c) Relay setting details
Constituents are requested to bring/ furnish full particulars of the tripping events pertaining to their system.
3.2 In compliance of Regulations 5.2 (r) of IEGC, the Constituents are required to furnish
the following information in respect of Grid Occurrences within 24 hrs of occurrence of the same to SRLDC/ SRPC: (a) First Information Report (FIR) (b) Event Logger (EL) output (c) Disturbance Recorder (DR) output (d) Trip event analysis report (with pre and post fault system conditions) Non-furnishing of tripping details (FIR/DR/EL/TR) for the period 01.06.2018 – 30.06.2018 had been brought to Constituents’ notice vide letters (i) No. SRPC/ SE-III/ PCSC/ 2018/ 3937 - 46 dated 20.06.2018, (ii) No. SRPC/ SE-III/ PCSC/ 2018/ 4536- 54 dated 13.07.2018. Non-compliance in this regard would be discussed in the meeting.
4. Submission of Reports/ Compliance by Constituents
4.1 Status of implementation of pending Protection Coordination
Sub-Committee (PCSC) Recommendations
The status of implementation of pending PCSC recommendations (up to 74th PCSC meeting) is given at Annexure-II. The latest status on the same may please be sent latest by 20.07.2018.
Agenda for the 76th
Meeting of PCSC scheduled to be held on 26th
July, 2018 Page 2
4.2 Remedial measures for "Transmission Elements under Forced Outage"
The Constituents are requested to furnish the remedial measures/ action taken by them for the tripping events as circulated vide our emails. (Annexure-III)
The tripping events are based on the daily reports at SRLDC website http://srldc.in/Reports.aspx under the menu: Reports->Daily-> "TL under Forced Outage")
4.3 Certificate for Healthiness of Batteries
As per the MoP direction given in pursuant to recommendations of the Enquiry Committee (NEW grid disturbance on 30th & 31st July, 2012), RPC’s are required to obtain from their respective Constituents the monthly certificate for healthiness of batteries, installed at 220 KV and above voltage level Substations (for power supply to Relays, RTUs and PLCC equipment) and furnish the same to CEA/ MoP.
With reference to above, the Constituents have been requested to submit the certificate on healthiness of batteries on monthly basis (i.e. status for a month shall be sent by the 7th day of the following month) to SRPC Secretariat.
The sought status for the months of June, 2018 is awaited from the following SR-Constituents:
KPTCL, TANGEDCO, TANTRANSCO, Puducherry ED, PGCIL (SR-I) & NTPC (Ramagundam)
5. Review of Compliance of Recommendations given in the Special Meeting on HVDC
Gajuwaka Pole Trippings held on 02.04.2018
A Special Meeting was held on 02nd April, 2018 at RHQ POWERGRID (SRTS-I), Hyderabad to deliberate on all outstanding issues involved in the recent HVDC Gajuwaka Pole trippings. The minutes of the meeting were issued vide SRPC letter no: SRPC/ SE-III/ SPM/ 2018/ 2015-19 dated 11.04.2018. Since it is proposed to review the status of implementation of the recommendations given in the meeting (present status enclosed at Annexure-IV), PGCIL (SR-I) is requested to furnish the updated status latest by 20.07.2018 for discussion during the meeting.
6. Auto-Reclosure Implementation (with Carrier Communication) on all 220 kV &
above Transmission Lines of Southern Region
It is common knowledge that majority of the faults that occur on transmission lines are of transient nature; hence provision of Auto-Reclosure certainly helps not only in preventing forced outage of the subject transmission line, but also in averting cascade trippings, in some cases, of adjacent transmission lines due to consequent over-loading. Further, the provision for Auto-Reclosure is also mandated by Regulation 43 (4) (c) of CEA Technical Standards for Construction of Electrical Plants and Electric Lines, 2010, which has force of law. Therefore, it is in the interest of grid security that all Constituents implement auto-reclosure feature on all 220 kV & above transmission lines in their respective control areas. Any exceptions to this needed to be properly justified. In this connection, the status furnished by SR-Constituents w.r.t. implementation status of A/R on their 220 kV & above transmission lines in SR-grid and the action plan furnished for
Agenda for the 76th
Meeting of PCSC scheduled to be held on 26th
July, 2018 Page 3
implementing A/R where it is presently not in service is enclosed at Annexure-V for kind reference. The latest status of A/R implementation by SR-Constituents on their 220 kV & above transmission lines in SR-grid and the action plan proposed for implementing A/R where it is presently not in service (present status) is proposed to be reviewed in the meeting. Since it is proposed to review A/R implementation in SR in the meeting, all concerned Constituents [APGENCO (Hydro), APGENCO (Thermal), APTRANSCO, TSGENCO (Thermal), TSGENCO (Hydro), TSTRANSCO, KPCL, KPTCL, KSEBL, TANGEDCO, TANTRANSCO, NPCIL (KKNPP), NPCIL (MAPS), NLCIL, UPCL & JSWEL] are requested to furnish (i) latest status of A/R implementation on their lines, and (ii) revised timelines, if any, latest by 20.07.2018 for discussion during the meeting. It may also be noted that the same status would be put up for discussion during the forthcoming TCC – 33 & SRPC-34 meetings.
7. Review of Compliance Status of New Protection Audit Recommendations
As part of GSC (Task-II) under Package-A, protection audit check of 15 stations was carried out byM/s Tractebel Engineering (TE) in the southern region during the period, December, 2015– July, 2016, when certain recommendations were also given for each of these stations for compliance. Subsequently, protection audit of various stations in SR has also been regularly conducted by SRPC teams in line with CERC Order dated 27.04.2015 in respect of APTRANSCO Petition No.95/MP/2015 dated 09.04.2015. So far, protection audit of 11 stations was carried out during the period December, 2016 – July, 2018, when certain recommendations were also given for each of these stations for compliance. The list of Stations audited & compliance % of the recommendations given is given below for kind reference:
Sl. No. Name of the Station Period of Protection Audit Compliance %
APTRANSCO 30.65
1 400/ 220 kV Narnoor SS 16–18 February, 2016 61.29
2 400/ 220 kV Uravakonda SS 5-6 April, 2018 0.00
TSGENCO (Thermal) 58.50
1 (i) 220 kV KTPS (O&M) 14-16 March, 2016 50.00
1 (ii) 220 kV KTPS (Stage-V) 14-16 March, 2016 40.90
1 (iii) 220 kV KTPS (Stage-VI) 14-16 March, 2016 84.67
TSTRANSCO 72.72
1 400/ 220 kV Shankarapally SS 20-21 March, 2017 72.72
KPCL 30.34
1 400 kV & 220 kV Raichur TPS 8-10 June, 2016 36.58
2 220 kV Nagjheri PH 14-16 July, 2016 41.93
3 220kV Sharavathy GS 30-31 October, 2017 12.50
KPTCL 51.13
1 400/ 220 kV Guttur SS 4-6 May, 2016 65.12
2 400/ 220 kV Nelamangala SS 8–10 February, 2016 37.14
KSEBL 27.91
1 220 kV Edamon SS 18-20 January, 2016 27.91
TANTRANSCO 17.07
Agenda for the 76th
Meeting of PCSC scheduled to be held on 26th
July, 2018 Page 4
1 400/ 230 kV Alamathy SS 4-6 January, 2016 38.71
2 230 kV Alundur SS 17 December, 2016 12.50
3 400/ 230 – 110 kV Palavadi SS 14-15 May, 2018 0.00
Puducherry ED 10.10
1 230/ 110 kV Villianur SS 10 July, 2017 9.67
2 230/ 110 kV Bahour SS 11 July, 2017 10.52
PGCIL (SR-I) 40.00
1 400 kV & HVDC Gazuwaka SS 28-30 December, 2015 50.00
2 400/ 220 kV Gooty SS 12th,13th and 15th February, 2016 50.00
3 765/ 400 kV Nellore PS 19-20 June, 2017 60.00
4 765/ 400 kV Maheshwaram SS 8-9 February, 2018 0.00
PGCIL (SR-II) 43.75
1 400 kVHosur SS of PGCIL (SR-II) 9-11 December, 2015 25.00
2 400 kV Tirunelveli SS 8th, ,9th and 11th January, 2016 50.00
3 400 kV Alundur SS 16 December, 2016 100.00
4 400/ 220 kV Kozhikode SS 21-22 December, 2017 0.00
NTPC 85.00
1 400 kV Ramagundam STPS 18-20 February, 2016 85.00
NPCIL 33.33
1 220 kV Kaiga GS 4-6 April, 2016 33.33
NLCIL 50.00
1 400 kV NLC TPS-II Station 8–10 February, 2016 50.00
The status of compliance of recommendations given for the above stations is circulated vide SRPC mail dated 12.06.2018 (Copy enclosed at Annexure-V). Since it is proposed to review compliance of these new protection audit recommendations in the meeting, all concerned Constituents [APTRANSCO, TSGENCO, TSTRANSCO, KPCL, KPTCL, KSEBL, TANTRANSCO, Puducherry ED, NTPC (RSTPS), NPCIL (KGS), NLCIL, PGCIL (SR-I) & PGCIL (SR-II)] are requested to furnish latest status in this regard to us latest by 20.07.2018 for discussion during the meeting. It may also be noted that the same status would be put up for discussion during the forthcoming TCC – 33 & SRPC-34 meetings.
8. Other Protection Issues, if any, with the permission of the Chair
9. Sending Agenda items for the PCSC meetings
As per the Guidelines of CEA/MOP, it has been decided to conduct the PCSC meetings on monthly basis. It is requested that Agenda Items for the PCSC meetings, if any, may please be sent latest by 5th working day of the month to SRPC Secretariat to compile and circulate the same so as to have fruitful discussions in the PCSC meetings.
10. Date of next PCSC meeting
It is informed that the 77th meeting of PCSC will be held on 21st August, 2018 (Tuesday) from 10:30 hrs onwards in the Conference Hall of SRPC Secretariat, Bengaluru.
*****
Grid Occurrences to be discussed in the 76th Meeting of PCSC scheduled to be held on 26th July, 2018 1/4
Grid Occurrences - 76
For all tripping events involving failure of substation equipment, Constituents are requested to kindly furnish the SLD or equivalent pictorial representation showing (i) Location of the fault, and (ii) Bus-bar arrangement/ Configuration of feeders and other connected equipment with proper CB positions (OPEN/ CLOSE) at the time of occurrence of the fault.
I. Details of Grid Disturbances:
Sl. No.
Details of Event Date &Time Reason Remarks Category
1 Complete outage of 230kV Villianur station
15-06-2018 at 7:29 hrs
Triggering incident was failure of B-phase 230KV Current Transformer of HV-I Breaker of 230/110KV 100MVA Auto Transformer-I. Fault was cleared by tripping of source feeders i.e. 230KV Neyveli-Villianur Line breaker at NLC TS-II and 230KV Pondy-Villianur Line Breaker at 400KV Pondy S/S. Fault cleared in 350 ms as observed from PMU data plot.
Load loss - 102 MW
GD-1
2 Complete outage of 220kV Sedam Station
19-06-2018 at 1:41 hrs
Triggering incident was B-phase to ground fault in 220kV Sedam – RTPS line-1. Bus bar protection operated and all connected lines tripped resulting in complete outage of Sedam station.
Load loss - 25 MW
GD-1
II. Details of Grid Incidents:
Sl. No. Details of Event Date &Time Reason Category
1 Tripping of 400/ 220 kV ICT-1 at BTPS
01-06-18 at 00:01 hrs
As per FIR ICT-1 got tripped on operation of backup over-current protection (high set) during R-N fault in 220kV BTPS-LINGAPUR line
GI-2
27-06-18 at 4:17 hrs
ICT-1 at BTPS got tripped during fault in 220KV BTPS-ALLIPUR LINE. Back up O/C & E/F relay at 220KV side of ICT got operated
GI-2
2 Tripping of 400 kV Trichy – Karaikudy line
02-06-18 at 1:33 hrs, Line tripped on operation of over-voltage
stg-1 protection at Karaikudi and direct trip received at Trichy. At Karaikudi, R-phase voltage was higher when compared with Y & B phases
GI-2 04-06-18 at 21:38 hrs,
05-06-18 at 21:01 hrs,
06-06-18 at
Annexure-I
Grid Occurrences to be discussed in the 76th Meeting of PCSC scheduled to be held on 26th July, 2018 2/4
22:50 hrs,
14-06-18 at 4:33 hrs,
19-06-18 at 20:59 hrs
3 Tripping of 400 kV Ghani – Narnoor line- 2
02-Jun-2018 at 05:35 hrs
Line tripped tripped on mal-operation of TIE LBB at Narnoor end and DT receive was received at Ghani.
GI-2
4 Tripping of 400 kV Guttur – Hiriyur line-2
04-06-2018 at 01:31 hrs
Line tripped on operation of over-voltage stg-1 protection at Hiryur and direct trip was received at Guttur end. B-phase voltage is comparatively higher when compared to R & Y phase at Hiryur
GI-2 05-06-2018 at 02:02 hrs
06-06-2018 at 2:00 hrs
5 Tripping of 400 kV Kurnool – Srisailam line
04-06-2018 at 17:03 hrs
Line tripped on operation of over-voltage stg-1 protection at Srisailam and direct trip was received at Kurnool. Voltages difference observed between R, Y & B phase at recorded in Srisailam end
GI-2
21-06-2018 at 23:56 hrs
6 Tripping of 400 kV Gooty-Kurnool (AP)
07-06-18 at 1:37 hrs
Line tripped on operation of over-voltage stg-1 protection at Kurnool(AP) and direct trip was received at Gooty. The Y phase Voltage was higher when compared to R & B phase at Kurnool(AP)
GI-2 14-06-18 at 1:39 hrs
15-06-18 at 00:28 hrs
15-06-18 at 23:46 hrs
28-06-18 at 01:59 hrs
7 Tripping of 400 kV Salem - Udumalpet line-1
08-06-2018 at 08:48 hrs
Line tripped on operation of instantaneous over-voltage during fault in adjacent K.R Thoppur S/S (ICT Rph bushing failure). Line was in service from Udumalpet end.
GI-2
8 Tripping of 765kV Kurnool – Nellore PS line-1
10-06-2018 at 15:53hrs
765kV KURNOOL - NPS line-1 tripped at NPS end only during LA failure in 765kV Kurnool-Thiruvelam line-2.
GI-2
9 Tripping of 230 kV Thiruvelam-Chitoor line
13-06-2018 at 18:55hrs
Y-phase to earth fault occurred in line. At 230KV Tiruvelam end, breaker was under lockout leading to operation of LBB
GI-1
10 400/220 kV ICT-2 at Raichur
17-06-2018 at 03:54 hrs
ICT-2 got tripped on operation of 220KV side over-flux protection.
GI-1
Annexure-I
Grid Occurrences to be discussed in the 76th Meeting of PCSC scheduled to be held on 26th July, 2018 3/4
11 Complete outage of 220kV Hoody SS
17-06-2018 at 3:53 hrs
Triggering incident was R-phase HV side CT flashover of 220/110kV, 100MVA transformer-3 and snapping of R phase jumper of CT connected to 220/110kV transformer-4 at Hoody. 400/220kV, 500MVA ICT-1 and 3 also tripped on operation of earth fault protection.
GI-1
12 Tripping of HVDC Talcher-Kolar pole- 1 and 2
18-Jun-2018 at 17:42 hrs
Trip command was generated from the DC station control system at Talcher end due to tripping of AC filters. ESOF was received at Kolar
13 Tripping of 400kV Veltoor - Uravakonda-1
20-06-2018 at 08:07 hrs
Line tripped on operation of over-voltage protection at Uruvakonda and direct trip was received at Veltoor. DR of Uruvakonda substaiton was not furnished to validate the operation of over-voltage protection
GI-2
14 Tripping of 400 kV Kurnool – Srisailam line
20-06-2018 at 18:52 hrs
Line tripped at Srisailam end and was holding from Kurool. At 20:02 hrs, direct trip was received at Kurnool end.
GI-2
15
400 kV Tiruvelam-Kalivandapattu line-2
21-06-2018 at 04:29 hrs
Line tripped on operation of over-voltage stg-1 protection at Thiruvelam end and DT was received at kalivandapattu. At Thiruvelam end, Y-phase voltage was high when compared to R and B phase.
GI-2
16
Tripping of 400kV Madurai-Tirunelveli-2 & 400kV Kudankulam-Tirunelveli-1
21-06-2018 at 17:37 hrs
400kV Kudankulam-Tirunelveli line-1 got tripped from Tirunelveli end only and line was holding from Kudankulam during R-phase Main bay CT failure occurred in 400kV Madurai-Tirunelveli line-2
GI-2
17
Tripping of 400/110kV PALAVADI-ICT-3 and 400 kV THIRUVALEM - PALAVADI-1
25-Jun-2018 at 17:14 hrs
Triggering incident was failure of B-phase CT of 400/110kV PALAVADI-ICT-3. Bus1 BBP operated. 400 kV THIRUVALEM - PALAVADI-1 tripped at Palavadi end only on actuation of over flux relay.
GI-2
18 Tripping of HVDC Bhadrawati Pole-1&2
25-Jun-2018 at 19:33 hrs
HVDC Pole-1&2 went into standby mode due to tripping of AC filters which in-turn tripped on operation of resistor thermal overload & IDMT earth Fault protection.
19 Tripping of 400kV 400kV JSW-BPS-2 & 400kV YTPS-BPS line-1
27-Jun-2018 at 17:24 hrs
400kV JSW TORANAGALLU BPS-2 tripped at BPS end on direct trip receive. 400kV YTPS-BPS line-1 tripped at YTPS end only. This happened during R- phase to earth fault occurred in 400kV YTPS-BPS-2 line
GI-2
Annexure-I
Grid Occurrences to be discussed in the 76th Meeting of PCSC scheduled to be held on 26th July, 2018 4/4
III. Details of Trippings due to Failure or Non-operation of Auto-Reclose:
Sl. No. Element Date & Time Reason
1 Tripping of 400 kV Khammam – Mamidapally line-1
01-Jun-2018 at 17:57 hrs
Y-phase to earth fault occurred in line. Auto-reclose was successful at Mamidapalli end. At Khammam end Main & Tie breaker got tripped due to operation of DEF.
2
Tripping of 400KV-SURYAPET-K.V.KOTA-1
01-Jun-2018 at 19:17 hrs
R-phase to earth fault occurred in line. Auto-reclose was successful at Suryapet and breakers got tripped at K.V.Kota
3 Tripping of 400kV Yelahanka Neelamangala
02-06-2018 at 19:53 hrs
R-phase to earth fault occurred in line. Auto-reclose was successful at Yelahanka end and breakers got tripped at Nelamnagala.
4 Tripping of 400kV YTPS-BPS line-1
03-Jun-2018 16:03
B-phase to earth fault occurred in 400kV YTPS-BPS line-1. Line did not auto-reclose from both ends.
5 Tripping of 400 kV Warangal – Boopalapalli line-1
21-Jun-2018 21:51:00
R-phase to earth fault occurred in line. Auto-reclose was successful at Kakatiya TPS end. At Warangal end there was Zone-2 trip due to non-receipt of Carrier signal.
IV. Details of Trippings due to PLCC mal-operation:
Sl. No. Element Date & Time Reason
1 Tripping of 400kV JSW-BPS line-1
03-Jun-2018 16:03hrs
B-phase to earth fault occurred in 400kV YTPS-BPS line-1. 400kV JSW-BPS line-1 got tripped due to spurious DT send from JSW end.
2 Tripping of 400 kV Warangal – Boopalapalli line- 2
14-Jun-2018 11:31hrs
Line tripped at Warangal end on DT receive and line was holding from KTPP end.
*****
Annexure-I
Meeting
No /
Index
Details of Event Date & Time Reason PCSC Recommendations Utility
responsible for
Implementation
Status of Implementation of PCSC Recommendations Remarks
34/I/6 400/220 kV ICT-1 & 2 at
Munirabad
As reported directional over current relay of ICT’s
operated due to snapping of line jumper in 220kV
Lingapur line.
1. Bus bar protection shall be provided by asset owner ( i.e
KPTCL).
2. Settings for main distance protection & Overcurrent
protection shall be examined and reviewed.
3. Time synchronization of the Substation shall be ensured.
KPTCL/
PGCIL (SR-I)
Pending
(with KPTCL)
Status of Pending Implementation of PCSC Recommendations as on 13.07.2018 (up to 74th Meeting)
KPTCL Mail dated 27-05-2015:
1. KPTCL has taken action to provide bus bar protection to 220kV buses. --- Pending
2. Over current relay Settings of ICTs to be reviewed by PGCIL.
--- Pending
3. --- Pending
KPTCL Mail dated 29-07-2015:
1. Initial Tendering stage. --- Pending
2. --- Pending
3. --- Pending
KPTCL Mail dated on 23-01-2016:
1. Detailed estimate prepared for taking up the work. CEE, Transmission Zone, Gulbarga will take
up necessary procurement and further execution. --- Pending
2. --- Pending with PGCIL (SR-I).
3. --- Pending
PGCIL (SR-I) Mail dated 14.07.2016:
2. Relay settings of all the stations in SRTS-1 were derived as per Ramakrishna Commettee
recomendations and implemented" --- Completed.
KPTCL Mail dated 16.12.2017:
1) & 3). DPR is approved. Tender is to be called by CEE,TZ Kalaburgi --- Pending
Review Meeting dated 19.12.2017:
1. KPTCL informed that Tenders for providing BBP would be called in Jan-Feb, 2018; Supply of the
same is targeted by September, 2018; Erection & Commissioning is targeted by January, 2019
--- Pending
3. PGCIL (SR-I) informed that time-synchronization of 220 kV side is in place. --- Completed.
16-07-2014
Multi-Utilities
Annexure-II
Page 1 of 47
PGCIL (SR-I) mail dated 20.06.2018:
PGCI(SR1) procuring LDP relays for retrofitting of Main-1&2 distance relays. Tenders are invited
from bidders & tender floated. Technical bid opening in this week.
Pending
[with
PGCIL (SR-I)]
APGENCO/
PGCIL (SR-I)
1. APGENCO to furnish to PCSC forum (i) A3-size Single Line
Diagram of SDSTPS, and (ii) the sequence of events with time
stamp showing the protection that opened Tie-CB (405) at
SDSTPS.
2. APGENCO to review STUB/TEED protection in all dias at
SDSTPS and ensure that they are configured for instantaneous
operation.
3. APGENCO to properly configure the STATE of the tripping
events so that they get recorded appropriately like TRIP/
OPERATED in their corresponding Event Loggers.
4. APGENCO to ensure time sync of all DR’s and EL’s at
SDSTPS.
5. PGCIL (SR-I) to provide line differential protection for 400
kV NPS –Nellore-PG lines 1 & 2.
As per FIR submitted, CT damage observed in Chitoor-
Main bay (404). Main breakers connected to bus-1 (401,
404, 407, 410) got tripped on operation of bus bar
protection. Unit-1 tripped on operation of MFT. Unit-2
was not in service
Complete outage of
Krishnapatnam TPS
08-09-2015
at 18:20 hrs
47/I/2 APGENCO letter dated 18.03.2016:
1.SOE and SLD are attached. The DR of 405 CB is not generated during the incident. Now the
problem is identified and rectified.
--------- Completed
2.All the 3 lines i.e CHTR-2, MNBL-I & II tripped in zone
protection. The fault was in Blind zone i.e P2 side of CT, where it was covered under Bus fault by
the time fault moved on to P1 side when the fault comes under STUB/TEED zone after 330msec
all the feeders expect CHTR-1 tripped in Zone-II and total fault persisted for 500msec before the
405 TIE CB opens and clear the fault. As a remedial the STUB protection operation also checked
and found OK.------- Completed
3.The Time Sync was missed on the day and found there was problem with LAN Timer same was
rectified. Now found OK.
-----------Completed
4.Now the DR Time scale changed to 1 sec for Pre fault and 3 sec for Post fault and STATE of
events are corrected wherever found wrong/or misguiding during analysis.---------Completed.
PGCIL-SR1 RVMD 27-04-2016:
5. Procurement of differential protection for 400kV NPS-NLR D/C and 400kV RCR-RTPS-D/C is
under tendering.
PGCIL-SR1 RVMD 14-07-2016:
5. The proposal for procurement of Line differential Protections for 400kV Raichur - RTPS-1 & 2
and 400kV Nellore - NPS - 1 & 2 lines has been approved and tender is under technical
evaluation
PGCIL (SR-I) Mail dated 15.12.2017:
PGCIL: On 23.11.2017 LDP relays commissioned in place of Main-1 distance relay in 400kV NPS-
Nellore line-2 & In line-1 installation of LDP relay is planned in Dec-2017/Jan-2018.
Review Meeting dated 19.12.2017:
5. PGCIL (SR-I) informed that LDP commissioning on both lines would be completed by February,
2018. In this regard, PCSC made it clear that the recommendation pertains to providing LDP as
both Main-I & Main-II on both the lines, and asked PGCIL (SR-I) to ensure & comply with the
same.
Annexure-II
Page 2 of 47
PGCIL (SR-I) mail received on 27-04-2016:
1. The firmware of REL670 is being upgraded. ------- Completed.
2. The recording of events in msec interval is being taken up with OEM. Henceforth, for analysis
purpose, we will provide larm list which has msec time stamp. -------- Completed.
3. End to end testing of PLCC code transmision and tuning of channels carried out. -------
Completed.
4. Procurement of differential protection for 400kV NPS-NLR D/C and 400kV RCR-RTPS-D/C is
under tendering. The legends modified in Event/alarm list. Provision of diff. relay for all short
lines emanating from NPS is being taken up with our corporate.
----- Pending.
PGCIL(SR-I) RVMD 14-07-2016:
4. The proposal for procurement of Line differential Protections for 400kV Raichur - RTPS-1 & 2
and 400kV Nellore - NPS - 1 & 2 lines has been approved and tender is under technical
evaluation --- Pending
PGCIL (SR-I) Mail dated 15.12.2017:
4. LDP relays procurement is under process. Procurement will be completed by Feb-2018. TPCIL
has to give written confirmation for LDP relay procurement. For want of written confirmation
from TPCIL, PGCIL approving authority has withheld the LDP proposal.
Review Meeting dated 19.12.2017:
4. PGCIL (SR-I) informed that they are waiting for written confirmation from TPCIL to complete
procurement of LDP relays. To this, PCSC forum asked TPCIL to submit written confirmation to
PGCIL (SR-I) by 29.12.2017. PGCIL (SR-I) assured that with receipt of above confirmation from
TPCIL by Dec, 2017, they would be able to complete the work by FEbruary, 2018.
APTRANSCO informed that they would be able to implement LDP from their & APGENCO side by
April, 2018.
In this regard, PCSC forum made it clear that the recommendation is about providing LDP as
both Main-I & Main-II relays on all stated lines in Nellore Complex, ans asked all stakeholders to
ensure & comply with the same.
Pending
Tripping of 220 kV Kadra-Karwar
lines - 1&2 and 220kV Kaiga-
Kadra line
50/I/2 Complete outage of TPCIL power
station
30-12-2015 at
06:02hrs
Running units at Thermal Powertech power Station
tripped due to tripping of 400kV Nellore pooling station
(NPS)-TPCIL line and 400kV Nellore pooling station (NPS)-
NCC line
47/II/7 KPTCL Mail recieved on 25-05-2016:
1. Availability of week end infeed with eco feature to be confirmed by SEE,RTC,Hubli ---
Pending.
NPCIL (KGA) Mail recieved on 03-12-2016:
2. The 200 ms Definite time DEFR element in both Kaiga Kadra and Kaiga Kodasally lines were
disabled. IDMT DEFR is retained. The 200 ms Definite time back up o/c element in both Kaiga
Kadra and Kaiga Kodasally lines were disabled. IDMT is retained. --- Completed.
Status received vide KPCL mail dated 14.06.2017 & 29.11.2017:
1. Since PT blasted (B phase) at Karwar end, resistive over reach occurred. hence Backup
protecion operated at Kadra end (zone-2 not sensed) --- Pending.
2. ---- Completed
3.Newly commissioned micom P444 relay time synchronised with GPS ------ Completed.
KPTCL Mail dated 16.12.2017:
1. Week end infeed logic will be enabled in the new numerical relays supplied to Karwar under
R&U during retrofitting works.
--- Pending
Review Meeting dated 19.12.2017:
1. KPTCL informed that since the line is a double circuit, there may not be need for implementing
Weak Infeed logic with Echo feature at Karwar end. However, the same would be looked into
w.r.t. the newly commissioned NR's at Karwar, and final action taken would be informed by
March, 2018.
Pending
[with KPTCL]
31-07-2015 at
11:44 hrs
KPTCL/ KPCL/
NPCIL (KGS)
1. KPTCL/ KPCL to see the possibility of implementing Weak
Infeed logic with Echo feature enabled by Under
Voltage (27) element on Kadra-Karwar lines 1 &2, and
implement the same if feasible.
2. NPCIL to time-coordinate Kaiga’s DEFR settings with (i)
Zone-2 settings at Kaiga, and (ii) primary protections of the
lines emanating from Kadra and Kodasalli.
3. KPCL to ensure time-sync of EL’s, and healthiness of the
Fault Locators at Kadra.
220kV Kadra-Karwar lines-1&2 tripped
on earth fault in B-phase in zone-2.
Kaiga-Kadra line tripped at Kaiga end
only on operation of directional eath
fault protection.
1.PGCIL (SR-I) to furnish Action Taken Report on the findings
of OEM on relay mal-operation at NPS end on 400 kV NPS –
NCC line to PCSC forum.
2. PGCIL (SR-I) to appropriately configure Station Event Logger
at NPS to record events at msec interval.
3. PGCIL (SR-I) to carry out PLCC end-to-end testing in
coordination with TPCIL for 400 kV NPS –TPCIL line.
4.PGCIL (SR-I), MEPL, SEL, TPCIL & NCC to take steps to
provide line differential protection at their respective ends on
all 400 kV lines (except Gooty line) emanating from Nellore
Pooling Station, and furnish an action plan to implement the
same.
PGCIL (SR-I),
MEPL, SEL, TPCIL,
NCC
Annexure-II
Page 3 of 47
PGCIL (SR-I) mail dated 20.06.2018:
PGCI(SR1) procuring LDP relays for retrofitting of Main-1&2 distance relays. Tenders are invited
from bidders & tender floated. Technical bid opening in this week.
Pending50/I/2 Complete outage of TPCIL power
station
30-12-2015 at
06:02hrs
Running units at Thermal Powertech power Station
tripped due to tripping of 400kV Nellore pooling station
(NPS)-TPCIL line and 400kV Nellore pooling station (NPS)-
NCC line
1.PGCIL (SR-I) to furnish Action Taken Report on the findings
of OEM on relay mal-operation at NPS end on 400 kV NPS –
NCC line to PCSC forum.
2. PGCIL (SR-I) to appropriately configure Station Event Logger
at NPS to record events at msec interval.
3. PGCIL (SR-I) to carry out PLCC end-to-end testing in
coordination with TPCIL for 400 kV NPS –TPCIL line.
4.PGCIL (SR-I), MEPL, SEL, TPCIL & NCC to take steps to
provide line differential protection at their respective ends on
all 400 kV lines (except Gooty line) emanating from Nellore
Pooling Station, and furnish an action plan to implement the
same.
PGCIL (SR-I),
MEPL, SEL, TPCIL,
NCC
Annexure-II
Page 4 of 47
PGCIL mail received on 27-04-2016:
Being pursued with APTRANSCO
APTRANSCO mail dated on 22-06-2016:
AS maintenance being carrired out by PGCIL(SR-1), the required relay replacement
(wiring/programming) may also be carried out by PGCIL(SR-1).
PGCIL RVMD 14.07.2016:
1. The CB problem has been attended by POWERGRID by using OEM M/s BHEL services &
POWERGRID's O&M spares.
------ Completed.
2. Being pursued with APTRANSCO to replace the faulty Event Logger at Vijayawada (Nunna) SS. -
--- Pending
APTRANSCO mail dated on 31-08-2016 & 04.03.2017 & 24.05.2017:
As maintenance being carrired out by PGCIL(SR-1), the required relay replacement
(wiring/programming) may also be carried out by PGCIL(SR-1).
APTRANSCO mail dated 20.10.2017:
May be coordinated with PGCIL
APTRANSCO mail dated 22.11.2017:
PGCIL may be requested to take necessary action
APTRANSCO mail dated 15.12.2017:
2. EL procured and drawn. Configuration to be done by Alstorm company engineer. Will be
configured in four weeks.
---Pending
PGCIL (SR-I) Mail dated 15.12.2017:
2. APTRANSCO is to replace the faulty/outdated relays & POWERGRID has to maintain the relays
after retrofitting.
Review Meeting dated 19.12.2017:
2. APTRANSCO informed that the recommended works would be completed in one-month
period.
APTRANSCO Mail dated 30.01.2018 & 24.05.2018 & 26.06.2018
As per the requirement of PGCIL.Event logger(BCU) with data base is configured and handed
over to PGCIL/Nunna on 27 th dec 17.PGCIL is requested to take action for taking event logger
(BCU) into service.
PGCIL (SR-I) mail dated 20.06.2018:
PGCIL(SR1): New event logger was given by APTRANSCO to be installed & commissioned by
APTRANSCO.
As asset belongs to APTRANSCO & they have to commission the same.
56/I/2 Complete outage of 220kV
Sedam Substation of KPTCL.
19-06-2016 at
15:27hrs
220kV Sedam-Humnabad-2 tripped at Sedam on
Distance protection, Zone-2. Sedam-RTPS-1 &2 lines
tripped at RTPS end only. 220kV Tandoor inter-state line
was hand tripped due to incoming supply failure
KPTCL and TSTRANSCO to take steps to provide A/R feature
on 220 kV Sedam – Tandur inter-state line at their respective
ends at the earliest.
KPTCL/
TSTRANSCO
KPTCL Mail dated 16.12.2017:
Carrier protection is to be restored. B/U OC and EF relay is to be replaced by M-II distance
relay. Required materials like wave trap, M-II distance relay are already supplied. The work will
be taken up on top priority through GE Ltd. --- Pending
Review Meeting dated 19.12.2017:
TSTRANSCO informed that they have kept A/R in service from Tandur end. KPTCL informed that
the works relating to put A/R in service are going on at their Sedam SS, and assured that it would
be put into service by February, 2018.
Pending
[with KPTCL]
Pending
[with PGCIL (SR-I)]
1. PGCIL (SR-I), in co-ordination with APTRANSCO, to address
the problem with CB at the earliest opportune time.
2. APTRANSCO to take steps to replace the faulty Event
Logger at Vijayawada (Nunna) SS.
Line tripped due to operation of over voltage protection
at Vijayawada end and Direct Trip was received at
Sattenapalli end
Tripping of 400kV Sattenapalli-
Vijayawada line
PGCIL (SR-I)/
APTRANSCO
25-12-2015 at 3:01
hrs
51/II/6
Annexure-II
Page 5 of 47
APTRANSCO mail dated on 31-08-2016:
To avoid the unwanted malopeartions due to the external LBB trip initiation from PGCIL, Vide
letter Dt: 04-08-2016, APTRANSCO has requsted the PGCIL to arrange the Master trip relay and
breaker contacts of ICT-1 &2 LV side to enable the internal LBB feature in the Busbar protection
scheme at 220kV Gooty Switching station. Waiting for the PGCIL response.
APTRANSCO mail dated on 15-11-2016:
To avoid the unwanted maloperations due to the external LBB trip initiation from PGCIL, vide
letter Dt: 04-08-2016, ARTRANSCO has requested the PGCIL to arrange the Master trip relay and
breaker contacts of ICT-1&2 LV side to enable the internal LBB feature in the Busbar protection
scheme at 220kV Gooty Switching station. Waiting for the PGCIL response.
APTRANSCO mail dated on 20-12-2016:
Waiting for the PGCIL response.
APTRANSCO mail dated 04.03.2017 & 24.05.2017.
SRPC is requested to coordinate with PGCIL in takind necessary action.
APTRANSCO mail dated 20.09.2017 & 22.11.2017
PGCIL may be requested to take necessary action
APTRANSCO maild ated 15.12.2017:
1. Cable healthiness checked and found ok. But it is proposed to replace the cable with armored
cable. --Completed
2. After replacing the cable contactors will be removed so as to avoid unwarrented delays in
transmitting trigging signal to the central unit . ---Pending
Review Meeting dated 19.12.2017:
APTRANSCO informed that replacement of the existing cable with armoured cable and
subsequent removal of cable contactors would be completed by 31.12.2017. In this regard,
PGCIL (SR-I) also assured that they would render all required help from their side to complete
the stated works in time.
APTRANSCO Mail Dated 30.01.2018:
New armoured cable is laid from 220 kv Gooty (AP) to 400/220 kv Gooty (PGCIL) for replacing
the existing cable connected to ICT-2.PGCIL is requested to provide spare contacts from trip
relays of 315 mva LV-1 and LV-2 for providing internal CB failure in busbar protection scheme.
APTRANSCO Mail Dated 24.04.2018 & 24.05.2018:
As requested by PGCIL the busbar drawings Were submitted for providing spare contacts from
trip relays of 315 mva LV-1 and LV-2 for providing LBB in busbar protection scheme.
PGCIL (SR-I) mail dated 20.06.2018:
220kV CB LBB protection (Stand alone protection) available at PGCIL end is to protect ICT in case
of non tripping of CB. It is opined that stand alone protection is better than new LBB logic
proposed by APTRANSCO in Busbar schme. The reason for mal-operation of 220kV Bus on
24.06.2016 is mainly due to cable issue. The problem shall be solved once we replace, this
suspected cable betweem POWERGRID & APTRANSCO.
24-06-2016 at 16:04
hrs
LBB protection got operated for 400/220kV ICT-2 breaker
which had resulted in tripping of 220kV Bus-2 at 220kV
Gooty Substation
Tripping at 220 kV Gooty
Substation of APTRANSCO
56/II/13 1.APTRANSCO to check the healthiness of the connecting
cable between Gooty (PGCIL) and Gooty (APTRANSCO), and
replace it, if required.
2.APTRANSCO to ensure that the distributed architecture
employed in implementing busbar protection at their Gooty
220 kV SS does not introduce any unwarranted delays in
transmitting the triggering signals to the Central Unit.
Pending [ with
PGCIL (SR-I) ]
APTRANSCO/
PGCIL (SR-I)
Annexure-II
Page 6 of 47
56/III/4 Tripping of 220 kV Sedam-Tandur
line
03-06-2016
at 21:52 hrs
Line tripped on B-phase to earth fault. Auto-reclose is
not enabled for line.
KPTCL and TSTRANSCO to fast-track providing A/R on 220 kV
Sedam – Tandur line, and furnish an action plan of providing
the same by next PCSC meeting (PCSC-57).
KPTCL/
TSTRANSCO
KPTCL Mail dated 16.12.2017:
Carrier protection is to be restored. B/U OC and EF relay is to be replaced by M-II distance
relay. Required materials like wave trap, M-II distance relay are already supplied. The work will
be taken up on top priority through GE Ltd.
Review Meeting dated 19.12.2017:
TSTRANSCO informed that they have kept A/R in service from Tandur end. KPTCL informed that
the works relating to put A/R in service are gonig on at their Sedam SS, and assured that it would
be put into service by February, 2018.
TSTRANSCO MAIL DATED 20.01.2018:
As discussed in the review meeting on 19-12-2017, A/R is kept in service from
Tandur(TSTRANSCO) end.---Pending
TSTRANSCO MAIL DATED 19.03.2018:
Issue is not pending from TSTRANSCO side.
Pending
(With KPTCL)
57/I/1 Complete outage of 220 kV
Karwar Substation of KPTCL
12-07-2017
at 11:36 hrs
Triggering incident was failure of R phase PT in Bus-1 at
220kV Karwar substation. 220kV Kaiga-Kodasalli tripped
during the incident. Also bus shut down occurred at
Kadra and Kodasally stations.
1.NPCIL (KAPS) to disable DefiniteTime O/C relay, and put in
its place by IDMT O/C relay for backup protection on both 220
kV Kaiga – Kadra line and 220 kV Kaiga – Kodasalli line at
Kaiga end.
2.KPTCL to put bus bar protection in service at their 220 kV
Karwar SS at the earliest.
3.KPCL/ KPTCL to implement Weak In-feed Logic with Echo
feature enabled by Under Voltage (27) element on Kadra –
Karwar lines 1 & 2.
4.KPTCL to furnish equipment failure report of the current
incident to PSE&TD Division of CEA with a copy marked to
SRPC.
KPTCL/ KPCL/
NPCIL (KGS)
NPCIL(KGS) mail dated on 03-12-2016 & 29.11.2017:
1.The 200 ms Definite time DEFR element in both Kaiga Kadra and Kaiga Kodasally lines were
disabled. IDMT DEFR is retained. --- Completed
2. --- Pending
3. --- Pending
4. --- Pending
KPTCL Mail dated 16.12.2017:
2) Bus-bar protection panel is supplied under R&U. Replacement work will be taken up after
priority Sub stations.
--- Pending
3] Weak end Infeed logic available in new relays supplied; Will be enabled During R&U works. ---
Pending
4] Equipement failure reports are being sent to CEA regularly.
--- Completed
Review Meeting dated 19.12.2017:
2. KPTCL informed that the works relating to providing BBP are targeted to be completed by
March, 2018.
3. KPTCL informed that since the line is a double circuit, there may not be need for implementing
Weak Infeed logic with Echo feature at Karwar end. However, the same would be looked into
w.r.t. the newly commissioned NR's at Karwar, and final action taken would be informed by
March, 2018.
Pending
[with KPCL &
KPTCL]
Annexure-II
Page 7 of 47
APTRANSCO Mail Dated 24.04.2018:
ABB make LDP relays inspection is completed. SNEIDER make LDP relays inspection yet to be
completed. Delivery of relays expected in the 1st weak of May-2018.
APTRANSCO Mail Dated 24.05.2018:
SNEIDER make LDP relays inspection yet to be completed.Delivery of relays expected in the
month of june 2018.
PGCIL (SR-I) mail dated 20.06.2018:
PGCI(SR1) procuring LDP relays for retrofitting of Main-1&2 distance relays. Tenders are invited
from bidders & tender floated. Technical bid opening in this week.
APTRANSCO Mail Dated 26.06.2018:
ABB make LDP relays are delivered. Schneider make LDP relays inspection to be offered by the
company.
APTRANSCO mail dated on 20-12-2016:
Issue was addressed to the concerned for necessary action.
APTRANSCO mail dated on 24-05-2017:
Meeting was conducted and the relays procurement for all the loctions is under progress.
APTRANSCO mail dated on 20-10-2017 & 22.11.2017:
Relays procurement for all the locations is under progress.
APTRANSCO Mail dated 15.12.2017:
Technical bids opened. PQ evaluation under progress . Price bids expected to open in next
week.
PGCIL (SR-I) Mail dated 15.12.2017:
LDP relays procurement is under process. Procurement will be completed by Feb-2018. TPCIL
has to give written confirmation for LDP relay procurement. For want of written confirmation
from TPCIL, PGCIL approving authority has withheld the LDP proposal.
Review Meeting dated 19.12.2017:
PGCIL (SR-I) informed that they are waiting for written confirmation from TPCIL to complete
procurement of LDP relays. To this, PCSC forum asked TPCIL to submit written confirmation to
PGCIL (SR-I) by 29.12.2017. PGCIL (SR-I) assured that with receipt of above confirmation from
TPCIL by Dec, 2017, they would be able to complete the work by FEbruary, 2018.
APTRANSCO informed that they would be able to implement LDP from their & APGENCO side by
April, 2018.
In this regard, PCSC forum made it clear that the recommendation is about providing LDP as
both Main-I & Main-II relays on all stated lines in Nellore Complex, ans asked all stakeholders to
ensure & comply with the same.
APTRANSCO MAIL DATED 30.01.2018
Technical & financial bids are opened. Tenders will be awarded shortly.
PGCIL (SR-I), TPCIL, MEPL, SEL, SGPL, APTRANSCO, APGENCO
and SDSTPS to implement line differential protection on all
400 kV transmission lines (of length less than 50 km)
emanating from Nellore PS, Nellore (PG) SS, and Nellore (AP)
SS. [It may be noted here that the cut-off length of 50 km has
been specified with a view to exclude only long transmission
lines].
APGENCO/
PGCIL(SR-I)/
TPCIL/MEPL/SEL/
SGPL/ APTRANSCO
Pending57/II/9 Tripping of 400 kV Nellore (PG) -
NPS line-1, 400 kV
Krishnapatnam-Nellore (AP) lines
-1&2 and 400kV NPS - MEPL line
18-07-2016
at 19:05 hrs
Triggering incident was snapping of Y phase conductor in
400kV Nellore (PG) - NPS line-1. Distance relay at
Krishnapatnam end over-reached in Zone-1, and resulted
in tripping of 400kV Krishnapatnam – Nellore (AP) lines -
1&2 from Krishnapatnam end. Distance relay at MEPL
over-reached and resulted in tripping of MEPL-NPS line
from MEPL end.
Annexure-II
Page 8 of 47
63/II/9 Tripping of 400 kV YTPS-BTPS
line and 400 kV BTPS-JSWEL line
14-03-2017 at 19:11
hrs
R-phase to earth had occurred in 400kV BTPS-JSWEL line
and protection issued a 3 phase trip
1. JSWEL to follow file naming terminology provided by
SRPC for various tripping files uploaded in SRLDC’s TMS
portal.
2.JSWEL to furnish reasons for AR-BLOCK observed
during the instant tripping and remedial action taken
by them to keep A/R in service.
3. KPCL to configure DR & EL properly to record OVR
Stage-I & Stage-II protections at their BTPS station.
KPCL/ JSWEL Status received vide mail dated 14.12.2017:
1. JSWEL will follow the file naming terminology provided by SRPC during future uploads -----
Completed
2. Auto-reclosure is in service for JSW BTPS line. The reason for AR-Block was due to carrier fail
signal which was after the fault clearance. As per the attached event list, the fault occurred at
7:11:21:550 PM & the AR block appeared around 7:11:21:586 PM, after the clearance of the
fault at around 7:11:21:583 PM (3PH-TRIP) -----Completed
3. --- Pending with KPCL
Review Meeting dated 19.12.2017:
3. KPCL informed that DR's & EL's had been configured for OVR (Stage-I & Stage-II) protections at
their BTPS sttaion, and the exact date of completion of the same would be intimated soon.
JSWEL Status received vide mail dated 01.03.2018:
1. JSWEL will follow the file naming terminology provided by SRPC during future uploads.
2. Auto-reclosure is in service for JSW BTPS line. The reason for AR-Block was due to carrier fail
signal which was after the fault clearance. As per the attached event list, the fault occurred at
7:11:21:550 PM & the AR block appeared around 7:11:21:586 PM, after the clearance of the
fault at around 7:11:21:583 PM (3PH-TRIP)
Pending
Annexure-II
Page 9 of 47
64/I/1 Complete outage of North
Chennai TPS STG-2
24-04-2017
at 21:02hrs
Tripping of evacuating lines due to fault led to tripping of
Units
64/I/2 Complete outage of North
Chennai TPS STG-2
25-04-2017
at 18:27hrs
Tripping of evacuating lines due to fault led to tripping of
Unit
64/I/3 Complete outage of North
Chennai TPS STG-2
26-03-2017
at 21:09 hrs
Tripping of evacuating lines due to fault led to tripping of
running Unit at NCTPS Stg-2
TANTRANSCO MAIL DATED 22.05.2018:
Existing Porcelain insulators of all other 400kV feeders are being replaced with Polymer
insulators in a phased manner. Timeline: Sep-2018. Detailed plan of action will be submitted.
TANTRANSCO MAIL DATED 08.06.2018:
Existing Porcelain insulators of all other 400kV feeders are being replaced with Polymer
insulators in a phased manner. Timeline: Sep-2018. Detailed plan of action will be submitted.
TANTRANSCO/
PGCIL(SR-II)
TANTRANSCO and PGCIL (SR-II) to take steps to complete
insulator replacement works on the 400 kV lines owned by
them in Chennai area within 3 months.
Pending
[with
TANTRANSCO]
Status received vide TANTRANSCO mail dated 15-06-2017 & 04.08.2017 & 18.09.2017 & 12-12-
2017:
1. All the Porcelain insulators of 400kV NCTPS-II - Vallur feeders-1&2 were replaced with
Polymer insulators by 20.05.2017. -----Completed
2. Existing Porcelain insulators of all other 400kV feeders are being replaced with Polymer
insulators in a phased manner.
--- Pending
PGCIL (SR-II) Mail dated 11-12-2017:
Pertaining to POWERGRID all the porceleing insulators in the polluted streches has been
completed. - Completed.
Review Meeting dated 19.12.2017:
TANTRANSCO informed that a total of 597 insulators ahd alreeady been replaced, and the total
replacement would take another 9-month period.
In this regard, TANTRANSCO was asked to furnish detailed plan of action regarding replacement
of insulators on all 400 kV lines owned by them in Chennai area.
TANTRANSCO MAIL DATED 25.01.2018:
Existing Porcelain insulators of all other 400kV feeders are being replaced with Polymer
insulators in a phased manner. Timeline: Sep-2018. Detailed plan of action will be submitted.
Annexure-II
Page 10 of 47
1. --- Pending with TSGENCO
PGCIL (SR-I) Mail dated 15-12-2017:
2). TOR feature in MiCOM P444 relay enabled for 400kV KMM-KTPS lines at Khammam end. DT
send on TOR trip is not as per protection philosopy. However if SRPC/SRLDC gives separate
instructions exclusively for this line, the same shall be imoplemented after getting our CC
approval. --- Pending
3). At Khammam SS all DR & ELs are time synched. --- Completed.
4). --- Pending
TSGENCO Mail dated 18.12.2017:
1). If the auto reclose function dead time kept same at both ends as 1 sec uniformly. In case of
persistent fault, it leads to feed the fault from both ends and cause the generator breaker
switching on to high fault current and chances of pole slip. To avoid this time differentiated A/R
scheme to be implemented. In KTPS 400KV Line –I & II at KTPS end dead time is 1.2sec and at
KMM end it is 1sec.
In our relay 7SA522 does not have the adaptive dead time function A/R. Hence, it is requested to
send DT in case of on 3-phase trip and A/R unsuccessful at KMM end to avoid reclose attempt
from KTPS end after dead time (1.2Sec) for persistent faults.
We communicated to M/s Siemens to upgrade the firmware version regarding adaptive dead
time.
Hence, it is requested to review these settings to reduce the stress on Generating Station ---
Completed
Review Meeting dated 19.12.2017:
2. It was made clear to PGCIL (SR-I) that this is a specific case of those 400 kV lines where one
one of the ends is a generating station, and the other end is grid-connected substation having
TOR feature in line protection relays. The said recommendation of enabling TOR along with
sending DT to the other end is basically to ensure safety of Generating Units at the other end.
Accordingly, PGCIL (SR-I) was asked to take steps to ensure the same. --- Pending
4. PGCIL (SR-I) informed that shutdown was availed by TSGENCO on 14.12.2017, and all issues
relating to PLCC including end-to-end testing were carried out. --- Completed
PGCIL (SR-I) mail dated 20.06.2018:
2. Please mention clearly which feature to be enaled at KMM end(DT send feature on TOR or DT
send feature while 3-ph trip). SRPC may advise TS TRANSCO for arrangieing OEM (MiCOM p444
relay) service engineer for configuration & implementation of DT send for TOR trip, as the
feature is no where implemented in POWERGRID-SR1.--- Pending
4. 400kV KMM-KTPS-1 line PLCC system checked & End to end code transmission checked on
19.01.2018 & found ok. ---Completed
TSGENCO/
PGCIL (SR-I)
1. TSGENCO to keep uniform A/R dead-time of 1 sec on the
lines emanating from their KPTS station.
2. PGCIL (SR-I) to enable Trip-on-Reclose (TOR) functionality
for Zone-2 faults for Khammam – KTPS lines at Khammam
end, if such a feature is available in the concerned relay, and
to configure it for sending Direct Trip (DT) Command to KTPS
end.
3. PGCIL (SR-I) to set right time-sync issues w.r.t. Khammam
end Event Loggers on Khammam – KTPS lines.
4. For 400 kV Khammam – KTPS line-1, PGCIL (SR-I), in
coordination with TSGENCO, shall carry out the following:
(i) End-to-end communication for DT/ permissive & other
signals may be ensured by testing at both the ends.
(ii) Healthiness of PLCC system components (hardware and
software) at both ends shall be checked and faulty
components shall be repaired/ replaced.
66/ II/ 8 Tripping of 400 kV Khammam –
KTPS lines – 1 & 2
08-06-2017 at 18:32
hrs
Lines – 1 & 2 tripped on B-phase to earth faults Pending
[with
PGCIL (SR-I)]
Annexure-II
Page 11 of 47
66/ II/ 10 Tripping of 400/ 220 kV ICT’s – 3
& 4 at Ramagundam STPS
11-06-2017
at 19:46hrs
Triggering incident was failure of 220 kV
B-phase LA in ICT-3 LV extension feeder (220KV line-2)
at Malayalapalli substation
1. NTPC to disable high-set of DEFR on the 220 kV lines
emanating from their Ramagundam STPS.
2. NTPC/ TSTRANSCO to provide Line Differential Protection
(with or without pilot) on 220 kV Ramagundam –
Malayalapalli lines – 1 & 2 & 3.
NTPC-
Ramagundam/
TSTRANSCO
NTPC mail dated 07.12.2017:
1. High set DEFR on 220 KV lines is disabled ----Completed
2. ---- Pending
Review Meeting dated 19.12.2017:
TSTRANSCO informed that the works are under progress, and are targeted to be completed in 3
months time.
TSTRANSCO MAIL DATED 20.01.2018:
Line Differential Protection will be provided within 3 months i.e., by end of March, 2018.
TSTRANSCO MAIL DATED 20.04.2018:
Line Differential Protection relays are under procurement and will be provided by end of May,
2018.
TSTRANSCO MAIL DATED 17.05.2018:
Line Differential relays will be supplied to site by manufacturer by end of May, 2018 and
erection will be completed by end of June, 2018.
Pending
1. --- Pending
2. --- Pending
3. --- Pending
Status received vide NPCIL mail dated 29-11-2017:
4. The event logger(ESCADA) has inherent time resolution of 10 millisecond for digital inputs. In
future higesht resultion event logger history will be extratced for submission to grid authorities..-
-NPCIL-KAIGA ----Completed
Review Meeting dated 19.12.2017:
1). Kadra-kaiga 220KV line tripped on both end in Zone-1 distance protection. Fault distance is
0.9KM from kadra end. Kodasalli-Kadra 220KV tripped at Kodasalli end only in Zone-1 fault.
Reason for tripping is the both Kadra-kodasalli, kadra-Kaiga line are in same tower, hence same
fault reflected adjuscent line. Because of no Bus source, Kadra end relay stopped to detect,
hence Kadra end breaker was intact.
---- Completed
2). Issue relating to downloading of DRs & Els at Kadra PH rectified. --- Completed
3). KPCL informed that they have planned to take up providing double-bus operation at their 220
kV Kadra PH, 220 kV Gersoppa PH, and 220 kV Raichur TPS through PSDF funding, and DPR for
the same is under preparation. After obtaining approval of the same from their management,
other activities inluding tenders floating, approaching PSDF would be taken up. All these
activites are targeted to be completed within 2 years.
--- Pending
Complete outage of 220 kV
Kadra Power Station of KPCL.
68/I/2 KPCL/ NPCIL (KGS)1. KPCL to investigate the reasons for non-tripping of 220 kV
Kadra – Kodasalli line from Kadra end by any of the Main
protection relays, and opening of only B-ph pole at Kodasalli
end, and furnish an action taken report on the same.
2.KPCL to sort out issues relating to downloading of DR’s &
EL’s at Kadra PH at the earliest.
3. KPCL to use both the 220 kV buses as main buses under
normal operation, and to go for single bus operation only
during emergencies at their Kadra PH.
4. NPCIL (KGS) to configure time resolution of Event Loggers
to milli seconds at their Kaiga GS.
Triggering incident was tripping of 220 kV Kadra-
Kodasalli and 220 kV Kadra-Kaiga line. There was no
generation at Kadra in antecedent condition.
25-09-2017
at 11:41hrs
Pending
[with KPCL]
Annexure-II
Page 12 of 47
69/I/2 Complete outage of 400kV TPCIL
station
30-10-2017 at 21:37
hrs
400kV TPCIL - Nellore line-1 got tripped at TPCIL end
during failure of LA of Station Transformer-2 at TPCIL.
Running Units at TPCIL got tripped due to loss of
evacuating line. 400kV TPCIL - Nellore PS line-2 was
under emergency shutdown
1. TPCIL to configure DEF protection such that it remains in
blocked condition as long as Distance Protection is active, and
becomes active only when distance protection does not
pickup.
2.PGCIL (SR-I) to ensure healthiness of Carrier
communication, and the set PUP mode of carrier aided
scheme operates reliably on TPCIL lines 1 & 2.
TPCIL/
PGCIL (SR-I)
Review Meeting dated 19.12.2017:
PGCIL (SR-I) informed that they are waiting for written confirmation from TPCIL to complete
procurement of LDP relays. To this, PCSC forum asked TPCIL to submit written confirmation to
PGCIL (SR-I) by 29.12.2017. PGCIL (SR-I) assured that with receipt of above confirmation from
TPCIL by Dec, 2017, they would be able to complete the work by February, 2018.
APTRANSCO informed that they would be able to implement LDP from their & APGENCO side by
April, 2018.
In this regard, PCSC forum made it clear that the recommendation is about providing LDP as
both Main-I & Main-II relays on all stated lines in Nellore Complex, ans asked all stakeholders to
ensure & comply with the same.
PGCIL (SR-I) mail dated 20.06.2018:
PGCI(SR1) procuring LDP relays for retrofitting of Main-1&2 distance relays. Tenders are invited
from bidders & tender floated. Technical bid opening in this week.
Pending
69/III/3 Tripping of 400 kV Kurnool(PG) –
Kurnool(AP) line-2
02-10-2017 at 02:03
hrs
Line tripped on B-ph to ground fault. A/R was
unsuccessful at both Kurnool (AP) and Kurnool (PG) ends.
1) PGCIL (SR-I) and APTRANSCO to provide for Line
Differential Protection as both the Main protections on 400 kV
Kurnool (AP) – Kurnool (PG) lines 1 & 2 lines.
2) APTRANSCO to furnish an action taken report w.r.t.
resolving A/R non-operation at Kurnool-AP end for the subject
trippings and configure EL for capturing PDR operation at
their 400 kV Kurnool-AP SS.
APTRANSCO/
PGCIL (SR-I)
APTRANSCO maild ated 30.01.2018:
1. Pending...
2.A/R scheme on 400kV Kurnool (PGCIL) feeder-2 will be checked after getting LC.
APTRANSCO maild ated 24.04.2018 & 24.05.2018 & 26.06.2018:
1. Pending...
2. B Ph auxilary trip relay is found defective. The same is to be replaced by M/S PGCIL. Ii) PD
relay event is configured in the EL as per the recommendation.
PGCIL (SR-I) mail dated 20.06.2018:
1. ---Pending
2. PGCIl(SR-1): B-Ph auxiliary relay problem rectified at Narnoor end by replacing relay contact. ---
Completed
Pending
69/III/7 Tripping of 220 kV Ragulapadu –
Alipura line
12-10-2017 at 01:30
hrs
Line tripped on B-Ph to earth fault. A/R was successful at
Regulapadu and breakers at Alipura end got tripped.
KPTCL and APTRANSCO to sort out issues relating to
incongruence in denoting R, Y, B phases of the electric supply
on their respective sides.
APTRANSCO/
KPTCL
APTRANSCO maild ated 15.12.2017:
APTRANSCO would extend support and requirements if any ,for the rectification proposed by
KPTCL.
Review Meeting dated 19.12.2017:
It was noted that the original Gooty - Lingapur line got LILOed at BTPS, Alipura, and Ragulapadu.
It was also noted that Phase Discrepancy is being observed in Ragulapadu - Alipira section only.
When enquired about the same, KPTCL informed that they would examine the issue in detail,
and would inform the action lan proposed by next PCSC-71 meeting. On this, APTRANSCO was
also asked to render all help required from their side to KPTCL.
APTRANSCO maild dated 30.01.2018:
APTransco world extend required support .
APTRANSCO maild dated 24.04.2018 & 24.05.2018 & 26.06.2018:
AP Transco would extend required support for attending, phase discrepancy issue in ragulapadu-
Alipura line by KPTCL.
Pending [ with
KPTCL ]
Annexure-II
Page 13 of 47
72/II/4 Tripping of 400/ 220 kV Hoody
ICT-3 and 400 kV Kolar-Hoody
line-2
14-01-2014 at 17:42
hrs
Triggering incident was failure of Y-phase lightning
arrestor of 400kV Hoody-Kolar line-2 at Hoody end due
to which 400 kV Kolar – Hoody line-2 tripped on
operation of distance protection. At the same time
400/220 kV, 500 MVA ICT-3 at Hoody also tripped on
earth fault protection.
For the Hoody – Kolar line-2, the following shall be carried out
by KPTCL, in coordination with
PGCIL (SR-II):
(i) End-to-end communication for DT/ permissive & other
signals may be ensured by testing at both the ends.
(ii) Healthiness of PLCC system components (hardware and
software) at both ends shall be checked and faulty
components shall be repaired/ replaced.
KPTCL to keep A/R in service on Hoody – Kolar line-2 after
verifying the healthiness of PLCC communication.
KPTCL / PGCIL (SR-
II)
Yet to be informed Pending
73/II/7 Multiple trippings at 400 kV
Guttur Substation.
17-03-2018 at 08:25
hrs
400 kV Guttur-Kaiga-1 Breaker was in lock-out condition.
It was intended to take Kaiga line-1 on tie CB. While
carrying out this operation bus bar protection operated
at Guttur resulting in tripping of all connected elements.
1) NPCIL (KGS) to take steps to disable sending of DT to
remote ends upon 86X operation for any line protection
operation at its 400 kV KGS.
2) KPTCL to resolve PLCC issues on 400 kV Guttur –Kaiga lines
at the earliest.
KPTCL/
NPCIL [KGS]
KPTCL Mail dated
It is observed that the loop wire(i.e from BCU to CB closing coil)missed for A/R close operation to
CB remote close and it was given on 21.04.2018 in the presence of PGCIL authorities.
NPCIL (KGS) mail dated 25.06.2018:
1) KGS agreed to disable sending of DT to remote ends upon 86X operations for any line
protection operation at its 400kV KGS within one month.
2) KPTCL agreed to resolve the PLCC issues at Guttur SS at the earliest.
Pending
73/IV/3 Tripping of 400 kV Pondicherry-
S.V.Chatram line.
10-03-2018 at 17:58
hrs
Line tripped at SVChatram end only and was holding
from Puducherry. No fault was observed from DR of
S.V.Chatram. Suspected PLCC mal-operation.
For the line under consideration, the following shall be carried
out by PGCIL (SR-II), in coordination with TSTRANSCO:
(i) End-to-end communication for DT/ permissive & other
signals may be ensured by testing at both the ends.
(ii) Healthiness of PLCC system components (hardware and
software) at both ends shall be checked and faulty
components shall be repaired/ replaced.
TANTRANSCO/
PGCIL (SR-II)
TANTRANSCO Mail dated 22.05.2018 & 08.06.2018:
PLCC LINK will be checked on availing LC
Pending
27-03-2018 at 17:17
hrs (Line-1)
73/IV/7 Line-1&2 got tripped on Direct Trip receive at Karamadai
end and the line was in service from Arasur end.
Suspected PLCC mal-operation.
For the line under consideration, the following shall be carried
out by PGCIL (SR-II), in coordination with TANTRANSCO:
(i) End-to-end communication for DT/ permissive & other
signals may be ensured by testing at both the ends.
(ii) Healthiness of PLCC system components (hardware and
software) at both ends shall be checked and faulty
components shall be repaired/ replaced.
TANTRANSCO/
PGCIL(SR-II)
TANTRANSCO Mail dated 22.05.2018 & 08.06.2018:
Protection coupler NSD 570 “input ON Time delay” introduced as 10 msec at Karamadai end
during commissioning Subsequently Arasur end time delay introduced.
Pending
Annexure-II
Page 14 of 47
27-03-2018 at 18:11
hrs (Line-2)
74/I/1 Complete outage of 220 kV
Sedam Substation
01-04-2018 at
19:56hrs
Triggering incident was fault in 220 kV Sedam-Tandur
line. 220 kV Sedam-Shahapur, 220 kV Sedam-RTPS lines -
1&2 and 220 kV Sedam-Tandoor line tripped from RTPS,
Shahpur and Tandoor. Tripping of incoming lines to
Sedam caused shut down at Sedam Sub Station resulting
in complete outage of the station.
KPTCL and TSTRANSCO to establish PLCC link on 220 kV
Sedam – Tandur line, and implement A/R using PLCC carrier
communication.
KPTCL/TSTRANSCO TSTRANSCO mail dated 20.06.2018:
Will coordinate with KPTCL and arrange for procurement of PLCC panel at Tandur end.
pending
52/I/2
(GD)
Complete outage of 220 kV
Yerraguntla substation and
tripping of running Units at
Rayalaseema TPS
21-02-2016 at 10:39
hrs
HV B-Ph Current transformer of 100MVA Power
Transformer -1 failed resulting into a bus fault on 220KV
Bus-1. Unit-1 and Unit-5 at RYTPS tripped during the
fault at Yerraguntla substation
1. APGENCO to check associated logic for lube oil pump for
correct operation under transient low voltage conditions at
Rayalaseema TPS, Unit-1.
2. APGENCO to keep appropriate time delay/ fault ride
through delay (typically 2 sec) in VFD speed sensor relay at all
its generating Units including Rayalaseema TPS Units.
APGENCO Mail received on 27-07-2016:
1.The drop out relays of reducer oil pumps time setting was increased for all mills.So there will
not be any trip under transient low voltage condition.----Complied
2.The recommendation regarding 2 sec time delay will be implemented during unit shut down
and will be intimated immediately after implementation.------Pending
Review Meeting dated 19.12.2017:
It was noted that no APGENCO representative had come to attend the meeting.
Pending
73/IV/7 Line-1&2 got tripped on Direct Trip receive at Karamadai
end and the line was in service from Arasur end.
Suspected PLCC mal-operation.
For the line under consideration, the following shall be carried
out by PGCIL (SR-II), in coordination with TANTRANSCO:
(i) End-to-end communication for DT/ permissive & other
signals may be ensured by testing at both the ends.
(ii) Healthiness of PLCC system components (hardware and
software) at both ends shall be checked and faulty
components shall be repaired/ replaced.
TANTRANSCO/
PGCIL(SR-II)
TANTRANSCO Mail dated 22.05.2018 & 08.06.2018:
Protection coupler NSD 570 “input ON Time delay” introduced as 10 msec at Karamadai end
during commissioning Subsequently Arasur end time delay introduced.
Pending
Andhra Pradesh
Annexure-II
Page 15 of 47
57/II/9 Tripping of 400 kV Nellore (PG) -
NPS line-1, 400 kV
Krishnapatnam-Nellore (AP) lines
-1&2 and 400kV NPS - MEPL line
18-07-2016
at 19:05 hrs
Triggering incident was snapping of Y phase conductor in
400kV Nellore (PG) - NPS line-1. Distance relay at
Krishnapatnam end over-reached in Zone-1, and resulted
in tripping of 400kV Krishnapatnam – Nellore (AP) lines -
1&2 from Krishnapatnam end. Distance relay at MEPL
over-reached and resulted in tripping of MEPL-NPS line
from MEPL end.
APGENCO to furnish a report on the remedial action
implemented w.r.t. overreaching of Krishnapatnam end
distance relays during the tripping of 400 kV Nellore (PG) -
NPS line-1
APGENCO Review Meeting dated 19.12.2017:
It was noted that no APGENCO representative had come to attend the meeting.
APGENCO Mail dated 19.12.2017:
Procurement of relays is under progress
Pending
69/II/1 Multiple trippings at Tripping at
220 kV Srisailam Right Bank
power station
09-10-2017 at 14:39
hrs
220kV Srisailam RB – Markapuram S/C line and 220 kV
Srisailam – Podili S/C line tripped on operation of
distance protection. Srisailam Units - 3, 4, 6 and 7 got
tripped during the incident.
1.APGENCO to furnish compliance report on the
recommendations given by PSAG-9 team that had visited
Srisailam RB PH on 14-15 October, 2014.
2.APGENCO to carry out the following:
(i)Removal of DC earth leakage in station switchyard on
priority basis (latest by 10.12.2017)
(ii)Integration of Station earth-mat and Switchyard earth-
mat.
3. APGENCO to provide for numerical relays (as both Main-I &
Main-II) on all 220 kV feeders emanating from Srisailam RB
PH.
4.APGENCO to put A/R into service on all 220 kV feeders
emanating from Srisailam RB PH.
5.APGENCO to provide for Time Synchronization equipment
at their Srisailam RB PH to synchronize all protection relays
with GPS.
APGENCO APGENCO Mail dated 06.03.2018:
1. Complainance report on PSAG -9 recommendations is enclosed in next sheet.
--Completed
2. i ) Attended and removed the earth leakage. --Completed
2 ii) Procurement of material is under progress. --Pending
3. Material received at site. Work will be completed by April 2018. --Pending
4. Will be provided at the time of commissioning of new protection panels. --Pending
5. i) Time synchronization for Unit-4 both MAin- I & II relays was provided through SNTP.
--Completed
ii) Time synchronization for Unit-1,2 ,3,5,6, & 7 RET- 670 Main -II Relays was provided through
SNTP. --Completed
iii) Time synchronization for Unit -1,2,3,5,6, & 7 REG- 670 Main - I & II Relays was provided
through PPM. --Completed
APGENCO Mail dated 25.06.2018:
2 ii) Procurement of material is under progress.
3. New numerical Relay panels erection nad commissioning work is under progress. It will be
completed within two months for all feeders.
4. Work is under progress and it will be completed within two months for all feeders -Pending
Pending
74/I/5 Complete outage of 400 kV
Kalikiri station
25-04-2018 at 16:55
hrs
Triggering incident was Y-phase to ground fault in 400kV
Kalikiri - RYTPP line-2. 400kV Kalikiri- Chittoor lines - 1&2
got tripped from Chittoor end. This resulted in complete
outage of 400kV Kalikiri station.
APGENCO to furnish tripping files (FIR/DR/EL/TR) of an event
involving their system within 24-hrs of occurrence of the
same to SRLDC and SRPC in line with IEGC Regulation 5.2 (r).
APGENCO Yet to be informed Pending
Annexure-II
Page 16 of 47
74/II/5 Tripping of 400 kV Nellore-AP -
VTPS-IV
04-04-2018 at 15:49
hrs
Spurious trip signal from PRD of NGR of Nellore line
Reactor at VTPS end resulted in Direct Trip send to
Nellore (AP)
APGENCO to take steps to remove the observed DC leakage
at their VTPS-IV switchyard at the earliest.
APGENCO Yet to be informed Pending
74/II/21 Tripping of 400 KV Kalikiri –
RYTPP line-2
29-04-2018 at 19:29
hrs
Line tripped on operation of over-voltage protection at
RYTPP and Direct Trip receipt at Kalikiri. The correct
operation of over-voltage tripping could not be validated
as FIR, DR and EL of RYTPP and DR and EL of Kalikiri were
not furnished.
1). APGENCO to furnish detailed report on the reasons for the
tripping of the line including remedial measures taken.
2). APGENCO to ensure that the OVR-settings implemented at
Rayalaseema TPP are as per the SRPC provided settings issued
vide letter dated 01.05.2018, and confirm the same.
APGENCO Yet to be informed Pending
69/II/7 Tripping of 400 kV Uravakonda –
Jamalamadugu line-1
06-10-2017 at 10:22
hrs
Line tripped on overvoltage at Uravakonda end and
Direct Trip received at Jamalamadugu end. DR & EL of
Uravakonda end not furnished.
APTRANSCO to complete configuration of DR’s & EL’s for all
protections relays at their 400 kV Uravakonda SS, and render
them suitable for extraction/downloading of relevant tripping
records/ events within a month’s time.
APTRANSCO APTRANSCO Mail dated 15.12.2017 & Review Meeting dated 19.12.2017:
Instructions were issued for taking necessary action.
APTRANSCO maild dated 30.01.2018:
Configuration of DR & EL’s in the relays completed configuration of DR & EL at SAS is to be
verified.
APTRANSCO maild dated 24.05.2018:
Informed to M/S .Siemens for rectification.
Pending
72/I/2 Complete outage of 400 kV
Uravakonda Substation of
APTRANSCO
20-01-2018 at 4:48
hrs
400kV Uravakonda- Jammalmadugu line-1 tripped at
4:48hrs due to Y-phase to ground fault at both the ends.
400kV Uravakonda Jammalmadugu line-2,
Mahabubnagar line-1 and 2 were in open condition due
to high voltage. After tripping of 400kV UV Konda-
Jammalmadugu line-1, 400/220kV ICT #1,2,3 and 4 at
400kV UV Konda were hand tripped due to loss of
evacuating lines.
APTRANSCO to get checked Auto-Reclosure scheme
provided on 400 kV & 220 kV lines for correctness of
functionality & healthiness of the logic employed by April,
2018.
APTRANSCO APTRANSCO maild ated 24.05.2018:
Informed to M/S .Siemens for rectification.
Pending
Annexure-II
Page 17 of 47
73/I/7 Complete outage of 220 kV Vizag
(Gazuwaka) switching station
27-03-2018 at 16:14
hrs
Triggering incident was R-ph CT failure Bus-Coupler. This
resulted in tripping of all the connected elements due to
operation of bus bar protection.
1) APTRANSCO to furnish equipment failure report of the
current incident (CT blast) to PSE&TD Division of CEA with a
copy marked to SRPC.
2) APTRANSCO to take steps to provide one more thermo-
vision camera to Vizag division for use exclusively on 400 kV &
220 & 132 kV transmission lines emanating from Kalpaka,
Gajuwaka, VSS, Pendurti and other adjoining substations of
APTRANSCO.
APTRANSCO APTRANSCO Mail Dated 26.06.2018:
i) Vide Lr.No.CE/Tr/SE/Tr/DE/SS/ADE-4/F.No.1/D.No.138/18Dt:20.06.18. Equipment & failure
report communicated to CE(STED),CE/(IC),CEA.
---Complied.
ii) Indent is being processed.---Pending.
Pending
74/II/19 Tripping of 400 kV Maradam -
Kalpaka line-1&2
24-04-2018 at
11:53hrs
400kV Maradam-Kalpaka line-2 - B-phase to earth fault
had occurred in line. Auto-reclose was un-successful due
to persistent fault.
400kV Maradam-Kalpaka line-1 - Line tripped at
Maradam end only on B-N, zone-1. Suspected over-reach
of distance protection from Maradam end.
APTRANSCO to address and correct the A/R issues at
Maradam end on 400 kV Mardam – Kalpaka lines – 1 & 2, and
put the corrected A/R functionality into service.
APTRANSCO Yet to be informed Pending
Annexure-II
Page 18 of 47
61/III/5 Tripping of 400 kV Khammam -
KTPS line-2
24-12-2016 at 10:52
hrs
Line tripped on B-phase to earth fault. First fault was
persistent for 380 ms. Auto-reclose was successful at
Khammam end during 1st fault. 2nd fault occurred
during re-claim time of breaker hence Khammam end
breakers also got tripped.
1. TSGENCO to implement the SRPC agreed philosophy for
Power Swing Blocking in all distance relays on the feeders
emanating from KTPS.
2. For the line under consideration, TSGENCO to consult relays
OEM to migrate to new versions of Firmware (from 4.68.03 to
4.72.01) and Pset (from 4.63.04 to 4.70.02).
TSGENCO TSGENCO mail dated 30.03.2017:
1. According to SRPC phylosphy power swing block settings are changed to ALL ZONES BLOCK
EXCEPT ZONE1.
---------- Completed
2. M/s. Siemens is requested to depute the service Engineer to update the firm ware of existing
SIPROTEC relays in 400KV switch yard. This work will be completed on or before 15.04.2017.
----------- Pending
TSGENCO mail dated 08.12.2017:
1. --- Completed
2. As this KTPS line-II is being LILOed at KTPS, Stage-VII, those relays would be replaced with line
diff relays. --- Pending
Review Meeting dated 19.12.2017:
As recommeded, TSGENCO was asked to migrate to new versions of firmware in consultation
with relays OEM.
------- Pending
Pending
07-11-2017 at 23:02
hrs
09-11-2017 at 21:57
hrs
12-11-2017 at 20:54
hrs
17-11-2017 at 21:19
hrs
11-11-2017 at 22:02
hrs
12-11-2017 at 23:09
hrs
24-11-2017 at 18:46
hrs
11-12-2017 at 18:49
hrs
TSGENCO
TSGENCOTSGENCO to adopt stipulated OVR, Stage-I gradings for the
400 kV lines emanating from their 400 kV Srisailam LB RH, and
furnish an action taken report w.r.t. mitigating observed
voltage difference among R & Y & B phases
Line tripped on operation of Over-Voltage protection at
Srisailam and Direct Trip was received at Kurnool.
Considerable voltage difference was observed between
R, Y & B phases.
Yet to be informed TSGENCO to adopt stipulated OVR, Stage-I gradings for the
400 kV lines emanating from their 400 kV Srisailam LB RH, and
furnish an action taken report w.r.t. mitigating observed
voltage difference among R & Y & B phases.
70/II/2
Tripping of 400 kV Satenapalli-
Srisailam line-1
Yet to be informed Pending
Tripping of 400 kV Narnoor –
Srisailam LB line
Line tripped due to operation of over voltage protection
at Srisailam LB end. Considerable phase difference was
observed between phases at Srisailam end
Tripping of 400kV Kurnool-
Srisailam line
1. TSGENCO to take steps to replace the existing faulty CVT’s
at Srisalam end on 400 kV Srisailam – Narnoor line at the
earliest.
2. TSGENCO to adopt stipulated OVR, Stage-I gradings on all
400 kV transmission lines emanating from Srisaliam LB.
TSGENCO Yet to be informed
Line tripped on operation of over-voltage protection at
Srisailam and Direct Trip was received at Sattenapalli.
Considerable voltage difference was observed between
R, Y & B phases at Srisailam end.
71/II/7
70/II/3
Telangana
Pending
Pending
Annexure-II
Page 19 of 47
18-12-2017 at 19:10
hrs
74/II/2 Tripping of 400 kV Kurnool-
Srisailam line
01-04-2018 at 18:03
hrs
Line tripped on operation of Over Voltage Stg-1
protection at Srisailam and Direct Trip was received at
Kurnool. Considerable difference between Phase
voltages was observed in Srisailam end DR. (Vr-257kV, Vy-
246kV, Vb-239kV)
1). TSGENCO was asked to double—check the faulty CVT’s and
replace them at the earliest.
2). TSGENCO was also asked to implement new OVR gradings
issued vide SRPC letter dated 01.05.2018.
TSGENCO Yet to be informed Pending
74/II/4 Tripping of 400 kV Gajwel -
Shankarapally line-1 and 400kV
Gajwel-Hyderabad line
03-04-2018 at 14:13
hrs
400 kV Gajwel-Shankarapally line-1 tripped due to B-
phase to earth fault (persistent fault). At this instant, 400
kV Gajwel-Hyderabad line also tripped on operation of
over-voltage protection at Gajwel and Direct Trip was
received at Hyderabad.
TSTRANSCO to expedite commissioning of new numerical
relays (with voltage drop-off to pick-up ratio better than 0.97)
on all 400 kV lines at their Gajwel SS and implement OVR
(Stage-I & Stage-II) functionality from the numerical relays.
TSTRANSCO TSTRANSCO mail dated 20.06.2018:
New relays are available at site and will be commissioned by 2nd week of August-2018. Over
Voltage settings will be implemented in the new relays.
Pending
74/II/8 Tripping of 400/220 kV ICT-2 at
Gajwel
11-04-2018 at 5:50
hrs
400/220 kV ICT-2 at Gajwel tripped on mal-operation of
Buchholtz relay.
1). TSTRANSCO was asked to keep the ICT and its mechanical
protections under observation for detecting any slippages.
2). TSTRANSCO was also asked to configure capturing of
mechanical protections of ICT’s in the respective relay’s/
station’s event logger.
TSTRANSCO TSTRANSCO mail dated 20.06.2018:
1. Mechanical protections of ICTs is under observation.
2.New relays are available at site and will be commissioned by 2nd week of August-2018. The
mechanical protection of ICTs will be configured in the new relays.
Pending
The issue was discussed in PCSC-58 meeting held on 18.10.2016, when PCSC forum agreed to de-
link the implementation of the Item from the scope of Protection Audit Recommendations
(PAR), and pursue it as part of PCSC Recommendations.
TSGENCO mail dated 30-05-2017
Procurement of Differential Protection relays is under process and the work will be completed
by the end of November 2017.
TSGENCO mail dated 18-09-2017
Procurement of Line Differential Protection Relays is under process and the work will be
completed by the end of January 2018.
Review Meeting dated 19.12.2017:
TSGENCO informed that they are in constant touch with TSTRANSCO in this regard, and hope to
implement LDP by February, 2018.
TSTRANSCO informed that procurement of LDP relays is under progress, and assured that LDP
would be implemented in 3-months time.
TSTRANSCO MAIL DATED ON 20-01-2018:
The matter is being coordinated with TSGENCO.
TSTRANSCO MAIL DATED ON 05-03-2018:
As a part of implementation of line differential relays for short distance (Jurala PH to Jurala SS)
feeders, procurement of Line Differential Protection Relays are in process and the work will be
completed by the end of June 2018
Tripping of 400 kV Narnoor –
Srisailam LB line
Line tripped due to operation of over voltage protection
at Srisailam LB end. Considerable phase difference was
observed between phases at Srisailam end
PAR/
PCSC-58
Provision of line differential protection for Jurala line 1 & 2 (line length-1.45 KM) feeders at 220 kV Jurala HPS
[Carry-Over from Protection Audit Recommendations]
TSGENCO/
TSTRANSCO
Pending
1. TSGENCO to take steps to replace the existing faulty CVT’s
at Srisalam end on 400 kV Srisailam – Narnoor line at the
earliest.
2. TSGENCO to adopt stipulated OVR, Stage-I gradings on all
400 kV transmission lines emanating from Srisaliam LB.
TSGENCO Yet to be informed71/II/7 Pending
Annexure-II
Page 20 of 47
74/II/18 Tripping of 400 kV Srisailam-
Dindi line-2
24-04-2018 at 17:05
hrs
Line tripped at Srisailam end on operation of distance
protection B-E, Zone-1. There was no tripping at Dindi
end and line was holding from Dindi. B-phase to earth
fault occurred in 400 kV Mamidapally-Dindi line-2 at the
same time.
1) It was noted that tripping of 400 kV Srisailam – Dindi line-2
from Srisailam end for a fault on 400 kV Dindi – Mamidipally
line-2 was a typical case of Zone-1 Over-reach. Accordingly
TSGENCO was asked to review DPR, Zone settings of the
subject line along with checking mutual compensation factor.
TSGENCO was also asked to keep the line under observation
so as to determine the integrity and operation of the distance
protection relay under similar conditions.
2) W.r.t. OVR operation on 400 kV Dindi – Mamidipally line-2
at Dindi end, TSTRANSCO was asked to ensure that they kept
required time delay of 100 msec for OVR, Stage-II operation.
TSGENCO/
TSTRANSCO
TSTRANSCO mail dated 20.06.2018:
1. ---Pending.
2. Stage-2 Over Voltage setting time delay is 100msec on 400 kV Dindi – Mamidipally line-2 at
Dindi end. --- Completed
Pending
[with TSGENCO]
41/I/1 GD-1 at 220kV Kadra power
Station of KPCL
16-02-2015 at 12:56
hrs
Triggering incident was B-phase to earth fault had
occurred in 220kV Kadra-Kodasalli line. Line tripped from
Kodasalli end only. 220kV Kaiga-Kadra tripped in Zone-3
from Kaiga end. Tripping of evacuating lines caused bus
shut down at Kadra hydro station.
1. KPCL to make functional the Main2 (EPAC) relay with the
help of KPTCL at the earliest.
2. KPCL to investigate the reason for DC fuse fail during
transient fault in 220kV Kadra-Kodasalli line including the
testing/ checking of DC supply cables, breaker control cables,
and trip coils.
3. KPCL to ensure supply for Main-1& Main-2 protections,
Trip Coils (TC1, TC2) from separate battery banks.
KPCL Mail received on 28-05-2015:
1. Main-2 relays already installed and commissioned.
2. DC fuses are intact. Till date no such incidence occurred.
3. Possibility of DC-1 & DC-2 arrangement and splitting of DC will be reviewed.
Mail received on 07-07-2015 , 21-10-2015 and 23-11-2015:
1. --- Completed.
2. --- Completed.
3. Possibility of DC-1 & DC-2 arrangement and splitting of DC will be reviewed --- Pending
Status received vide KPCL mail dated 14.06.2017:
3. Providing 2 separate DC sources is under process --- Pending
Status received vide KPCL mail dated 14.12.2017:
3. Work under implementation stage --- Pending
Review Meeting dated 19.12.2017:
3. KPCL informed that for providing 2 separate DC sources with new battery charger, LOA &
Work order were placed on M/s Eltek Power system. The works would be completed in March,
2018. --- Pending
Pending
The issue was discussed in PCSC-58 meeting held on 18.10.2016, when PCSC forum agreed to de-
link the implementation of the Item from the scope of Protection Audit Recommendations
(PAR), and pursue it as part of PCSC Recommendations.
TSGENCO mail dated 30-05-2017
Procurement of Differential Protection relays is under process and the work will be completed
by the end of November 2017.
TSGENCO mail dated 18-09-2017
Procurement of Line Differential Protection Relays is under process and the work will be
completed by the end of January 2018.
Review Meeting dated 19.12.2017:
TSGENCO informed that they are in constant touch with TSTRANSCO in this regard, and hope to
implement LDP by February, 2018.
TSTRANSCO informed that procurement of LDP relays is under progress, and assured that LDP
would be implemented in 3-months time.
TSTRANSCO MAIL DATED ON 20-01-2018:
The matter is being coordinated with TSGENCO.
TSTRANSCO MAIL DATED ON 05-03-2018:
As a part of implementation of line differential relays for short distance (Jurala PH to Jurala SS)
feeders, procurement of Line Differential Protection Relays are in process and the work will be
completed by the end of June 2018
Karnataka
PAR/
PCSC-58
Provision of line differential protection for Jurala line 1 & 2 (line length-1.45 KM) feeders at 220 kV Jurala HPS
[Carry-Over from Protection Audit Recommendations]
TSGENCO/
TSTRANSCO
Pending
Annexure-II
Page 21 of 47
Mail received on 21-10-2015:
1) Anti-pumping contactors of all the nine 220KV Lines are in circuit and tested periodically
during AOH works of lines along with other protections.
2) Completed.
3) Possibility to use both the 220kV buses as main bus under normal operation is under review.
Mail recieved on 23-11-2015:
1) Completed
3) Two bus operation for 220kV buses : In place of existing CT switching relays, High speed
manual heavy duty change over switch of sufficient current capacity will be retrofitted to all
feeders at 220kV station and same will be operated manually during changeover of feeder by
one bus to the other and this arrangement may facilitate to put both buses in service. Time
required for this retrofit is around 90days . However, this work will be taken up only after
retrofitting of electromagnetic relays with numerical relays for Main-2 protection of all 220kV
lines, for which work is in progress.
Status received vide mail dated 10-07-2017:
1) --- Completed.
2) --- Completed. Status received vide KPCL mail dated 14.12.2017:
3) DPR for implementation of Two Bus operation for 220kV bus system has been prepared and
proposal is placed for funds from PSDF. After the approval of the DPR, the work is proposed to
be taken up.
Review Meeting dated 19.12.2017:
3) KPCL informed that DPR for implementation of Two Bus operation for 220kV bus system has
been prepared and proposal is placed for funds from PSDF. After the approval of the DPR, the
work is proposed to be taken up. Time frame requested for is 2 yrs.
54/II/4 Tripping of 400 kV Raichur TPS-
Mahboobnagar line
05-04-2016 at 10:23
hrs
Line tripped on operation of Backup impedance
protection of line reactor. Direct trip was received at
Mahboobnagar end.
KPCL to keep the functioning of the concerned electro-
mechanical back-up impedance protection relay under
observation, and replace it with a spare at the earliest.
KPCL Status received vide KPCL mail dated 10.07.2017:
The electro-mechanical back-up impedance protection relay is in service. However, Budgetary
offer obtained for the retrofitting of Line reactor protection with Numerical relay and is under
process
Status received vide KPCL mail dated 14.12.2017:
Tendering under process
Review Meeting dated 19.12.2017:
KPCL informed that the new numerical relay for backup impedance protection of Line Reactor
would be provided by June, 2018.
KPCL Mail dated 19.01.2018:
E-tender for the retrofitting work of Line Reactor protections will be invited shortly.
Pending
Status received vide KPCL mail dated 10.07.2017:
1. (ii) Hot line water washing stopped and off line water washing is carried out whenever the 400
KV Unit or line is under tripped condition / Shutdown condition. --- Completed
1. (iii) Silicon coating for Unit#8 main & tie breakers carried out in Sep'16 and same is under
observation. Till today in order and good condition. For remaining breakers, since it is big order,
approval for the same is under process. --- Pending
2. Static / Electromechanical relays are existing in all 1 to 7 units. Breaker flash over protection
feature will be enabled (if available) in the numerical relays which will be retrofitted in phased
manner during R&M works.
Status received vide KPCL mail dated 14.12.2017:
1.(i) --- Pending
Tripping of 400kV Raichur TPS
Bus-2
13-04-2016 at 21:12
hrs
1.KPCL to undertake the following remedial measures to
avoid breaker flashovers:
(i) Replacing all porcelain insulators with composite insulators
(ii) Carrying out hot-line water washing of all insulators on
regular basis.
(iii) Applying Room Temperature Vulcanizing (RTV) Silicone
high voltage insulator coatings to all bus-connected ceramic
insulators of equipment like CT, PT, CB, Isolators etc.
2.KPCL to take steps to provide dedicated breaker flashover
protection to all breakers at Raichur TPS at the earliest.
Y-ph Pole of Tie-breaker of Unit-4 at RTPS failed. Unit-4
got tripped on operation of Generator Differential,
Reverse power & LBB protection. Operation of LBB
protection led to tripping of BUS-2 at RTPS
46/II/21
54/II/9
Pending
Pending
07-06-2015 at 01:35
hrs
KPCL
KPCL1. KPCL to check the operation of anti-pumping relay on 220
kV side and keep it in healthy condition.
2. KPCL to provide manual reset to the 220 kV side master trip
relay.
3. KPCL to use both the 220 kV buses as main buses under
normal operation, and should go for single bus operation only
during emergencies.
Trippings at 220kV Raichur TPS
Annexure-II
Page 22 of 47
Review Meeting dated 19.12.2017:
1 (iii) As upgradation of 400kV switchyard equip's to be taken under PSDF funds, Silicon rubber
coating for breakers is deffered till then. --- Pending
2. Replacement by Num relay for Units - 5,6 & 7 completed in the month of Oct-2017. Main-I is
Seimens make and Main-II is ABB make. --- Pending
KPCL mail dated 19.01.2018:
2. Replacement of Numerical relays for Units-5, 6 & 7 have been completed. Referred to OEM for
providing the Breaker flashover protection for all the breakers.
54/II/13 Tripping of Units at 220 kV
Raichur TPS
15-04-2016 at 15:36
hrs
During testing of retrofitted distance protection in 400kV
Raichur-2 feeder, LBB protection trip DC got extended to
Bus trip. This resulted in tripping of 220kV bus at RTPS
and all connected 220 kV elements. Unit-4 which is
connected to 400 kV Bus got tripped due to tripping of
Station Utility Transformer that is connected 220 kV bus
In view of the availability of two buses along with healthy bus-
coupler at 220 kV RTPS, KPCL is recommended to put in
service the double-bus operation at 220 kV RTPS by suitably
distributing loads within 15 days.
KPCL Status received vide KPCL mail dated 10.07.2017 & 14.12.2017:
Two Bus operation for 220kV bus is being carried out whenever required. However scheme for
tripping of one bus during LBB/fault and maintaining the other bus intact by tripping B/C breaker
will be taken up in R&M works.
Review Meeting dated 19.12.2017:
3) KPCL informed that DPR for implementation of Two Bus operation for 220kV bus system has
been prepared and proposal is placed for funds from PSDF. After the approval of the DPR, the
work is proposed to be taken up. Time frame requested is 2 yrs.
Pending
Tripping of 400kV Raichur TPS
Bus-2
13-04-2016 at 21:12
hrs
1.KPCL to undertake the following remedial measures to
avoid breaker flashovers:
(i) Replacing all porcelain insulators with composite insulators
(ii) Carrying out hot-line water washing of all insulators on
regular basis.
(iii) Applying Room Temperature Vulcanizing (RTV) Silicone
high voltage insulator coatings to all bus-connected ceramic
insulators of equipment like CT, PT, CB, Isolators etc.
2.KPCL to take steps to provide dedicated breaker flashover
protection to all breakers at Raichur TPS at the earliest.
Y-ph Pole of Tie-breaker of Unit-4 at RTPS failed. Unit-4
got tripped on operation of Generator Differential,
Reverse power & LBB protection. Operation of LBB
protection led to tripping of BUS-2 at RTPS
54/II/9 PendingKPCL
Annexure-II
Page 23 of 47
58/I/3
(GD)
Complete outage of 220 kV
Kadra power station of KPCL
06-09-2016
at 14:40 hrs
LBB of 220kV Kodasalli breaker at Kadra end got
operated which resulted in tripping of Bus at Kadra and
in turn led to tripping of all elements
1) KPCL to check settings of LBB protection in all relays from
which it was implemented, and ensure that their
configuration, logic, and timing are in order at their 220 kV
Kadra PH.
2) KPCL to furnish details regarding the existing LT auxiliary
supply arrangement at their 220 kV Kadra PH, and take steps
to provide a suitable Auto-Main-Fail (AMF) panel for DG set to
effect its auto-starting in case of failure of LT supply.
3) KPCL to ensure time-sync of all relays (DR’s & EL’s) with GPS
at their 220 kV Kadra PH.
4) KPCL to provide stand-alone Event Logger at their 220 kV
Nagjheri PH.
KPCL Status received vide KPCL mail dated 14.06.2017:
1. All logics checked and found normal. LBB timing checked and found 200msec as per KPTCL
MRT recommendation. - Completed
2. Work Under Progress ---- Pending
3. New GPS System commissioned along with new numerical and synchronised with GPS system -
Complied
4. Work Under Progress ---- Pending
Status received vide mail dated 14.12.2017:
1),3),4) Completed
2. Auto Start of DG set is taken up --- Pending
Review Meeting dated 19.12.2017:
2. KPCL informed that for AMF of DG, Scheme prepared & material procurement under process.
The AMF scheme will be implemented in January 2018. --- Pending
3. The GPS system commissioned on Nov 2016 & all the numarical relay time synchronised with
GPS ---- Completed
Pending
62/I/1 Complete outage of 220 kV
Nagjheri substation of KPCL
21-01-2017
at 00:38 hrs
Triggering event was the fault on 220 kV Nagjheri
–Kodasalli line-2. Both buses of 220 kV Nagjeri power
station of KPCL got
de-energized.
1. KPCL to adopt the following VT fuse-fail logic for all 220 kV
lines emanating from NPH:
“Under VT fuse fail condition, distance protection shall
normally be kept blocked. However, upon detection of a fault
(sensed by negative sequence component), blocking of
distance protection shall give rise to operation of its inherent
Over-Current protection set with a definite time delay of 500
msec”.
2. KPTCL/ KPCL to revise Zone-2, Zone-3 and Zone-4 (reverse)
timings of DPR of all 220 kV lines emanating from Nagjheri PH
in line with Ramakrishna Committee guidelines.
KPCL Status received vide mail dated 14.06.2017:
1. Already settings are discussed with EE(RT), Hubli and soon relays will be tested for VT fuse fail
condition.
2. Timings of Zones were set as per the recommendations of CE(RT) & R&D, KPTCL, Bangalore &
EE(RT), KPTCL, Hubli.Regarding revision of timings will be carried out in co- ordination with
EE(RT), KPTCL, Hubli.
Status received vide mail dated 14.12.2017:
1. As per the recommendations of SRPC and SRLDC, in the event of VT fuse fail, non directional
over current and earth fault feature is enabled in the distance relay with a definite time lag of
600msec on pick up and the same is tested by KPTCL Hubli(RT) and KPCL jointly on 18.05.2017.
--- Completed
2. --- Pending
Review Meeting dated 19.12.2017:
2. KPCL informed that Zone settings of distance relays of all 220 kV lines emanating from
Magjheri SS had been revised in line with Ramakrishna Committee guidelines.. --- Completed.
Pending
69/II/8 Tripping of 220 kV Kaiga- Kadra
line-1
06-10-2017 at 22:22
hrs
While de-synchronising of Unit-2, B-phase pole of GCB
did not open and pole descrepancy relay operated.
Hence all 220KV lines CB hand tripped.
KPCL to take steps to replace the existing static protection
relays for Generator Units and Generating Transformers
(GT’s) with suitable Numerical relays at their 220 kV Kadra PH.
KPCL Yet to be informed Pending
72/I/4 Complete outage of 220kV
Sedam, Shahapur, Shahabad,
Kapanoor, Humnabad and
Halabarga Stations of KPTCL
01-02-2018
at 17:46 hrs
High resistance fault occurred in 110kV Sedam-Chittapur
line near Sedam end. Line DEF operated and backup OC
protection of 100MVA transformer operated at Sedam
end. But line breaker and transformer HV breaker didn’t
open due to problem in trip circuit. This resulted in
cascade tripping of upstream feeders and power supply
was lost to six 220kV stations of KPTCL.
KPCL to disable GFC protection on all lines emanating from
their generating stations.
KPCL Yet to be informed Pending
Annexure-II
Page 24 of 47
73/I/5 Complete outage of 220kV
Varahi power station
15-03-2018 at 22:36
hrs
There was Y-phase to ground fault on 220 kV Varahi -
Shimoga line-2. Consequent to persisting fault in ‘Y’
phase, the breaker failure protection operated resulting
in operation of 220KV bus bar protection at Varahi,
tripping all the connected lines and Varahi running units.
KPCL to take steps to put double-bus operation into service at
their 220 kV Varahi PH.
KPCL Yet to be informed Pending
73/II/6 Multiple trippings at 220 kV
Sharavathy Power station.
15-03-2018
at 22:05 hrs
The incident happened during shifting of Unit-8 from 220
kV North West bus to 220 kV South West Bus. The 220 kV
buses got tied together without synchronizing which
resulted in operation of bus bar protection.
KPCL to take steps to using full-fledged Double Main-Bus
system with four sections instead of the present Single Main-
Bus with two sections at their 220 kV Sharavathy GS.
KPCL Yet to be informed Pending
Mail received on 28-04-2015:
1. In view of operating 220kV Ambewadi SS in split bus mode, action is being taken up by KPTCL.
Problem in the 220kV bus coupler breaker is attended and isolator overhauling work is under
progress. Spilt bus operation at Ambewadi will be made possible at the earliest. --- Pending
2. ICT Protection system at Ambewadi and trippings occured at Supa GS during the instance is
checked up and remedial measures already furnished in this regard.
---- Completed
Mail recieved on 29-07-2015:
1. Action is being taken by KPTCL for operating Ambewadi in split bus mode. Problem in bus
coupler breaker is attended.Isolator overhaulling work is completed.PTs are already provided to
220kV Bus-II. After commissioning of Bus-II PTs, Ambewadi can be operated in split bus mode.
Pending works will be completed within a months time.KPTCL Mail dated 16.12.2017 & Review Meeting dated 19.12.2017:
1. Recommended works at Ambewadi have not been taken up due to various problems faced
due to poor response from the turn key agency M/s ERL. A site meeting is planned during this
month to discuss about further plan of action for attending SRPC recommendations pertaining to
the Sub station.
The issue was discussed in the review meeting. Considering the importance of the substation
and delay in executing the works, it was decided to escalate all pending issues relating to
Ambewadi SS to KPTCL top Management for early completion.
GD-1 at 220kV Ambewadi Station
of KPTCL
Triggering incident was B-phase to earth fault in 220kV
Ambewadi- Nagzari line-1. B-pole of breaker did not
open at Ambewadi end. LBB protection not available at
Ambewadi end. All elements tripped on Zone-2 from
remote ends.
22-12-2014 at 21:22
hrs
1. Till the completion of R&M works for bus bar and LBB
protection, KPTCL shall explore the possibility of having split
bus operation at Ambewadi and submit the details of the
same to PCSC forum.
2. KPTCL shall provide the details of the tripping of Supa hydro
station connected downstream from 110 kV bus.
PendingKPTCL40/I/1
Annexure-II
Page 25 of 47
Mail received on 28-04-2015:
Procurement of Bus bar and LBB protection is in the final tendering stage. 2. Action is being
taken to restore the carrier protection for 220kV Sedam-Tandoor line. AR will be enabled.
Mail received on 29-07-2015:
1. Procurement of Bus bar and LBB protection is in the final tendering stage.
2. Action is being taken to restore the carrier protection for 220kV Sedam-Tandoor line. AR will
be enabled after restoration of PLCC.
KPTCL mail received on 23-01-2016:
1. Bus bar protection panels pocured and erected at Sedam. Wiring , testing ,commissioning is
being taken up.Planned to complete by April 2016.
2. Action is being taken to restore the carrier protection for 220kV Sedam-Tandoor line. AR will KPTCL Mail dated 16.12.2017:
1 & 2) Replacement of Bus Bar Protection is included under R&U project. Awarded to M/s GE Ltd.
Panels have alredy been supplied by the Agency. The work will be taken up on top priority.
Review Meeting dated 19.12.2017:
KPTCL informed that the works relating to put A/R in service are going on at their Sedam SS, and
assured that it would be put into service by February, 2018.
KPTCLKPTCL was requested to explore the possibility of providing
A/R feature to this line and submit the remedial measures to
the PCSC forum.
Complete outage at 220kV
Sedam Substation of KPTCL (GD-
1)
KPTCL 1. KPTCL to provide Bus bar and LBB protections for 220 kV
bus at Sedam S/s.
2. KPTCL to implement A/R feature on 220 kV Sedam-Tandur
inter-state line.
R-Phase to ground fault occurred on 220kV Sedam-
Shahpur line. Fault not cleared from Sedam end due to
stuck-breaker condition. While the Sedam- Sahapur line
tripped from Shahapur end in Zone-1, the other 220 kv
lines from Sedam tripped at remote ends in Zone-2. This
caused complete outage of 220kV Sedam substation.
27-01-2015 at 8.00
hrs
220kV Sedam-
Tandur line
Mail recieved on 29-07-2015:
Carrier protection is being restored for 220kV Sedam-Tandoor line at Sedam end. After restoring
the carrier protection , AR will be enabled.
KPTCL mail recieved on 23-01-2016:
Carrier protection is being restored for 220kV Sedam-Tandoor line at Sedam end. After restoring
the carrier protection , AR will be enabled.
KPTCL mail recieved on 25-05-2016:
SEE,SCADA to update the latest status
KPTCL mail recieved on 28-06-2016:
Action is being taken to restore carrier protection.AR will be enabled once carrier signal is
restored.
KPTCL Mail Recieved dated 22-11-2017:
The Wave traps required are supplied under R&U project and the same is to be commisioned at
Sedam end for restoration of PLCC. Also,M-II distance relays have already been supplied by GE
Ltd.
KPTCL Mail dated 16.12.2017:
Carrier protection is to be restored. B/U OC and EF relay is to be replaced by M-II distance
relay. Required materials like wave trap, M-II distance relay are already supplied. The work will
be taken up on top priority through GE Ltd.
Review Meeting dated 19.12.2017:
KPTCL informed that the works relating to put A/R in service are going on at their Sedam SS, and
assured that it would be put into service by February, 2018.
40/IV/1 20-12-2014
at 22:20 hrs
Line tripped on Yphase to earth fault from both the ends Pending
Pending41/I/4
Annexure-II
Page 26 of 47
42/I/1 Complete outage of 220kV
Sedam substation of KPTCL
15-02-2015
at 14:24 hrs
Fault occurred in 220kV Sedam-Shahpur line 1. KPTCL to provide Bus Bar protection and LBB protection at
Sedam S/s and furnish the status of their implementation to
PCSC forum.
2. KPTCL to implement A/R feature on 220 kV Sedam-Tandur
inter-state line.
KPTCL Mail received on 27-05-2015:
1. Bus Bar protection will be provded under R&U.
2. A/R yet to be enabled.
Mail received on 29-07-2015:
1. Procurement of Bus bar and LBB protection is in the final tendering stage.
2. Action is being taken to restore the carrier protection for 220kV Sedam-Tandoor line. AR will
be enabled after restoration of PLCC.
KPTCL Mail Recieved dated 22-11-2017:
Bus Bar Protection panel and required Wave traps are supplied under R&U. Wave trap to be
commisioned in Tandoor line and PLCC to be restored.Once PLCC is restored AR will be enabled.
KPTCL Mail dated 16.12.2017:
1. Replacement of Bus Bar Protection is included under R&U project. Awarded to M/s GE Ltd.
Panels have alredy been supplied by the Agency. The work will be taken up on top priority.
2. AR feature will be enabled during retrofitting of Main-2 relays.
Review Meeting dated 19.12.2017:
1 & 2) KPTCL informed that the works are under progress and are targeted to be completed by
February, 2018.
Pending
42/I/2
(GD)
Complete outage of 220 kV
Ambewadi substation of KPTCL
12-03-2015 at 7:51
hrs
Fault in 220kV Ambewadi-Nagjheri line-2 1. KPTCL shall provide A/R feature on Ambewadi – Ponda 220
kV D/C inter-state line.
2. Till the completion of R&M works for bus bar and LBB
protection, KPTCL shall explore the possibility of having split
bus operation at Ambewadi and submit the details of the
same to PCSC forum.
KPTCL Mail received on 29-07-2015:
1. Procurement of Bus bar and LBB protection is in the final tendering stage.
2. Action is being taken to restore the carrier protection for 220kV Sedam-Tandoor line. AR will
be enabled after restoration of PLCC.
KPTCL Mail Recieved dated 22-11-2017 & 16.12.2017:
1.Enabling the AR feature was discussed during PCSC meetings and since Ambewadi-Ponda and
Ambewadi-Xeldom lines are radial lines, it was decided that enabling AR is not required. To clear
the faults in the abovelines early, the timings of the Zone 2 was reduced to 150mS and the Back
Up EFR timings have been reducedto 150mS. --- Completed
2.The planned works as per R&M could not be taken up due to the problem with the vendor and
could not be taken up under R&U project due to administrative reasons. ---- Pending
Review Meeting dated 19.12.2017:
2. The issue was discussed. Considering the importance of the substation and delay in executing
the works, it was decided to escalate all pending issues relating to Ambewadi SS to KPTCL top
Management for early completion.
Pending
Annexure-II
Page 27 of 47
48/I/2 Complete outage of 220kV
Peenya Substation in Karnataka
27-09-2015
at 4:23:17 hrs
All connected 220kV lines and transformers were taken
on 220kV North bus as South bus was under shut down
for conversion of strung bus to rigid bus and isolator
replacement under R&M works. Failure of HV side Y
phase CT of 150MVA Transformer-3 occurred at Peenya
Substation which resulted in operation of Differential
and HV REF protection. The failure of CT also resulted in
a 220kV bus fault in North Bus.
KPTCL to revise distance relay settings at Nelamangala end
for 220 kV Nelamangala – Hebbal - Peenya line – 1 for the
effective line length of 17 km. These new settings can be
appropriately reviewed as and when the tie-arrangement at
Hebbal is done away with.
KPTCL KPTCL mail received on 25-05-2016:
Presentl 220kV Nelamangala -Hoody (i.e. nelamangala-Peenya-Hebbal -Hoody line is made LIILO
at Yelahanka sub station and breaker at Peenya is kept open, necessary modification in distance
relay settings adopted for new configuration.
KPTCL Mail Recieved dated 22-11-2017:
Since usage of this line as an Incoming line at Peenya is required for emrgency purposes, the
settings of this line at Nelamangala end will be reduced to 17KMs and as a special case, to cover
the rest of the length of the line, Zone 2 timing will be reduced to 150 ms.
KPTCL Mail dated 16.12.2017:
The revised settings to be adpopted for this line considering reduced protected line length(
17KMs) is issued as a special case which will be implemened and tested during scheduled
outage.
Review Meeting dated 19.12.2017:
KPTCL informed that the revised setting would be implemented by December, 2017.
KPTCL Mail dated 26.06.2018:
Attended . Revised settings adopted at Nelamangala and connectted sub stations.
Pending
Annexure-II
Page 28 of 47
48/I/3 Outage of 220kV Ambewadi
station in Karnataka
30-09-2015 at 10:41
hrs
220kV Ambewadi-Nagjheri line-2 tripped on B-phase to
earth fault. This resulted in loss of supply to 220kV
Ambewadi bus. 220kV Ambewadi-Ponda line-1&2 were
hand tripped after deenergization of bus at Ambewadi.
KPTCL to fast-track providing A/R on all 220 kV lines
emanating from Ambewadi SS to prevent Station shut-down
on temporary faults.
KPTCL KPTCL mail received on 23-01-2016:
Will be complied in a months time.
KPTCL Mail Recieved dated 22-11-2017:
Enabling the AR feature was discussed during PCSC meetings and since Ambewadi-Ponda and
Ambewadi-Xeldom lines are radial lines, it was decided that enabling AR is not required. To clear
the faults in the abovelines early, the timings of the Zone 2 was reduced to 150mS and the Back
Up EFR timings have been reducedto 150mS.
KPTCL Mail dated 16.12.2017:
Enabling the AR feature was discussed during PCSC meetings and since Ambewadi-Ponda and
Ambewadi-Xeldom lines are radial lines, it was decided that enabling AR is not required. To clear
the faults in the abovelines early, the timings of the Zone 2 was reduced to 150mS and the Back
Up EFR timings have been reduced to 150mS. In view of the above, it is requested to drop the
issue from this list.
Review Meeting dated 19.12.2017:
KPTCL informed that AR would be enabled at Ambewadi end for lines other than Ponda and
Xeldom lines during retrofitting of Back Up protection by Distance protection relay at Ambewadi.
Considering the importance of the substation and delay in executing various works, it was
decided to escalate all pending issues relating to Ambewadi SS to KPTCL top Management for
early completion.
Pending
KPTCL Mail received dated 25-05-2016:
SEE, RTC, Bangalore to update the status
KPTCL Mail received dated 28-06-2016:
Providing numerical bus bar protection to 400kV buses and GPS time synchronising equipment
at Guttur is considered under R&U. Work is awarded to M/s Alstom, execution will be taken up
shortly.
KPTCL Mail received dated 25-04-2017:
GPS and accessories will be supplied during May 2017, expected to complete the work within a
month after supply of materials.
KPTCL Mail dated 16.12.2017:
1). The work of replacing static type 400kV Bus Bar Protection scheme by numerical BBP is
under progress at Guttur.
--- Pending
2). GPS time syncronising device is expected to be supplied before end of December 2017 ---
Pending
Review Meeting dated 19.12.2017:
1) & 2) KPTCL informed that the works are under progress, and are targeted to br completed by
February, 2018.
KPTCL Mail dated 26.06.2018:
GPS time synchronisaionis provided for protection relays under R&U project. Replacement of
400kV BBP by numerical BBP is envisaged under R&U works. Additional quantity of controls
cables required to take up the BBP replacement work. Supply of control cables awaited.
Multiple tripping at 400kV Guttur
SS
1. KPTCL to configure all DR’s and EL’s at 400 kV Guttur SS so
that they will also get triggered for BBP operation.
2. KPTCL to ensure time-synchronization of all DR’s and EL’s
with GPS at their 400 kV Guttur SS.
51/II/21 Failure of Lightning Arrestor of Y-phase Line Reactor of
400kV Guttur-Hiriyur line-1 and line tripped on distance
protection Zone-1. Bus-bar protection of 400kV Bus-2 at
Guttur substation also got operated during the event
sensing this through fault. 400/220 kV ICT-1 & 2 at
Guttur, 400kV Kaiga-Guttur-2, 400kV
Guttur-Narendra-2, 400kV Guttur-Hiriyur-2 and 400kV
Guttur-Munirabad which are on 400kV Bus-2 got tripped
during the incident. 400kV Guttur-Narendra-1 which was
on Bus-1 also tripped at the same time.
17-01-2016 at 18:53
hrs
PendingKPTCL
Annexure-II
Page 29 of 47
52/I/3 Complete outage of 220 kV
Shimoga substation
22-02-2016 at 15:03
hrs
220kV Bus Bar protection operated during failure of R
phase CT in DVG-2 line bay.
KPTCL to operate 220 kV Shimoga on multi-bus operation
under normal conditions, and put it on single-bus operation
only under emergency conditions.
KPTCL KPTCL Mail received dated 25-04-2017:
Replacement of existing BBP by new BBP with 4 zone protection is being taken up under R&U.
KPTCL Mail Recieved dated 22-11-2017:
GE Ltd has already supplied the necessary Bus Bar protection panels for replacement of the
existing static type BBP by new numerical BBP with 4 zone protection under R&U project. The
work of commissioning the same will be taken up shortly.
KPTCL Mail dated 16.12.2017:
Due to operational constraints two/ multi bus operation is not being implemented.
Review Meeting dated 19.12.2017:
It was noted that Shimoga SS is having required configuration for providing double-bus
operation. However, due to large no. of feeders (15 in no) with variable gneration at certain
remote ends like Varahi, the flows on these lines are bound to vary. As such it is necessary to
zero in on appropriate arrangement of feeders on different buses so that bus-isolators of the
feeders are not overloaded.
The issue was discussed. KPTCL was asked to try out multi-bus operation on trial basis to arrive
at suitable arrangement of feeders.
Pending
53/I/1 Complete outage of 220kV
Peenya Substation of KPTCL
16-03-2016 at 11:39
Hrs
220kV Peenya-Nelamangala-3 tripped on B-E fault at
both ends. At the same time, 220kV Peenya-
Nelamangala-4 tripped on R-Y fault only at Nelamangala
end, and was in service from Peenya end. Due to tripping
of these two lines, 220kV Peenya-Nelamangala-2 tripped
on overcurrent protection.
KPTCL to furnish a report on the tripping of 220 kV Peenya-
Nelamangala line-4 Nelamangala detailing the remedial
measures taken including the settings adopted for Z1B (Zone
extension) and Power Swing Block.
KPTCL KPTCL Mail received dated 25-05-2016:
SEE, RTC, Bangalore to update the status
KPTCL Mail Recieved dated 22-11-2017:
Since usage of this line as an Incoming line at Peenya is required for emrgency purposes, the
settings of this line at Nelamangala end will be reduced to 17KMs and as a special case, to cover
the rest of the length of the line, Zone 2 timing will be reduced to 150 ms.
KPTCL Mail dated 16.12.2017:
Considering it as special case, revised settings to be adpopted for this line considering reduced
protected line length( 17KMs) is issued which will be implemened and tested during next
scheduled outage.
Review Meeting dated 19.12.2017:
KPTCL informed that the revised settings would be implemented by December, 2017.
Pending
57/II/1 Tripping of 220 kV Chikkodi-
Mudshingi and 220 kV Chikkodi-
Talandage lines
01-07-2016 at 03:03
hrs
Triggering incident was failure of B-ph PT of 220kV Bus-2
(western bus) at 220KV Chikkodi substation. 220KV
Chikodi- Belgaum-I line tripped on DEFR (Inst), 220KV
Chikkodi-Kudachi line tripped on Distance protection and
also 100MVA transformer-2 tripped on E/F protection.
1.KPTCL to take steps to provide busbar protection at their
220 kV Chikkodi inter-regional substation, and furnish a time-
line for the same.
2.KPTCL to review distance protection settings for 220 kV
Chikkodi – Kudachi line.
3.KPTCL to furnish equipment failure report of the current
incident to PSE&TD Division of CEA with a copy marked to
SRPC.
KPTCL KPTCL Mail Recieved dated 22-11-2017:
1. The necessary Bus Bar protection panels are already supplied to Chikkodi under R&U project.
Presently R&U works at sub stations subjected to audit are taken up. After completion of PAR
works, the baove works are planned.
--- Pending
2. --- Pending
3. --- Pending
KPTCL mail dated 16.12.2017:
1.The necessary Bus Bar protection panels are already supplied to Chikkodi under R&U project.
Control cables have to be supplied. Presently R&U works at sub stations subjected to audit are
taken up. After completion of PAR works at 26 Sub stations, remaining works will be taken up
through M/s GE.
--- Pending.
2. --- Pending
3. --- Pending
Review Meeting dated 19.12.2017:
1. KPTCL informed that BBP would be provided by April, 2018.
---- Pending
2. KPTCL informed that DPR settings had been reviewed.
---- Completed
3. EFR on failure of B-ph PT of 220 kV Bus-2 had been furnished to CEA. ---- Completed
Pending
Annexure-II
Page 30 of 47
62/II/3 Tripping of 220 kV Bus 2 and
connected elements (220kV HAL
#1 and 2, 400/220 kV ICT- 1, 2
and 220/66 kV ICT-2) at 400/220
kV Hoody substation of KPTCL
(Load loss : 590 MW)
09-01-2017
at 23:06 hrs
Failure of R-phase CT of 220/ 66 kV transformer-2 at
220kV Hoody end resulted in a bus fault in 220kV Bus-2.
Fault was cleared by backup protection of ICT's (220kV
lines were being radially operated) due to absence of
busbar protection
1. KPTCL to provide Busbar protection at their 220 kV Hoody
SS at the earliest.
2. KPTCL to furnish an Equipment Failure Report on CT failure
to CEA with a copy marked to SRPC.
KPTCL KPTCL mail received dated 25.04.2017:
Numerical BBP is being provided under R&M works.
KPTCL Mail Recieved dated 22-11-2017:
1. Numerical Bus Bar protection panels have already been supplied as a part of R&M works
awarded to GE Ltd. Due to issue regarding the sectionaliser CTs, the work had stopped. Now the
same is resolved and the the above work will be taken up after supply of sectionaliser CTs. ---
Pending
2. --- Pending
KPTCL Mail dated 16.12.2017:
1. Numerical Bus Bar protection panels have already been supplied as a part of R&M works
awarded to GE Ltd. Due to issue regarding the sectionaliser CTs, the work had stopped. Now the
same is resolved and the the above work will be taken up after supply of sectionaliser CTs. ---
Pending
2. --- Pending
Review Meeting dated 19.12.2017:
1. KPTCL informed that BBP at 220 kV Hoody would be provided by March, 2018.
---- Pending
2. EFR on failure of R-ph CT of 220/ 66 kV Transformer-2 had been furnished to CEA. ----
Completed
Pending
62/II/5 Tripping of 220 kV South Bus and
connected elements (220kV HSR,
220kV Nagnathpura, 220 kV
Harohalli, 220 kV
Subramanyapura, 220 kV
Tataguni, 220 kV Mallur and
400/220kV ICT-2 and 3) at
400/220kV Somanhalli
substation of KPTCL
(Load loss: 850 MW)
20-01-2017 at 14:34
hrs
Triggering incident was fault in 66 kV Somanahalli -
Bannerghatta line and fault was cleared by operation of
Back-up OCR at Somanahalli end.
KPTCL to provide numerical Busbar Protection at their 220 kV
Somanahalli SS at the earliest.
KPTCL KPTCL mail received dated 25.04.2017:
Numerical BBP is being provided under R&M works
KPTCL Mail Recieved dated 22-11-2017:
Tesing & Commissioning of numerical BBP at Somanahalli is under progress. There was some
technical issue wth BBP scheme supplied to Somanahally which is being finalised in consultation
with OEM SIFANG. Numerical BBP will be commissioned at Somanahally within a month's time.
KPTCL Mail dated 16.12.2017:
Numerical Bus Bar protection Scheme will be commissioned at Somanahally before end of
December 2017
Pending
69/III/5 Tripping of 220 kV Sedam-Tandur
line
10-10-2017 at 00:50
hrs &
10-10-2017 at 17:27
hrs
Tripped on Y-Phase to ground fault due to distance
protection operation. Auto reclosure could not be
validated from the submitted DR/EL.
KPTCL to enable and put A/R into service from Sedam end on
220 kV Sedam – Tandur S/C line.
KPTCL Review Meeting dated 19.12.2017:
KPTCL informed that the works relating to put A/R in service are going on at their Sedam SS, and
assured that it would be put into service by February, 2018.
Pending
72/I/3 Complete outage of 220kV TK
Halli, Kadakola,
Chamarajanagara and
Maduvinahally substation of
KPTCL
27-01-2018
at 12:41 hrs
Snapping of B-phase Jumper in 220 kV Bastipura -
Kadakola line-1 resulted in tripping of the line. 220kV
Bastipura-Kadakola line-2 also got tripped during fault in
line-1. Due to tripping of above lines bus shutdown
occurred at TK Halli, Madhuvanahally, Chamarajanagara
and Kadakola stations due to overloading of connected
lines.
1. KPTCL to provide the detailed logics of SPS proposed in
Hotagally – Bastipura – Kadakola area, and take steps to
implement the same at the earliest.
2. KPTCL to take steps to put A/R into service on 220 kV
Bastipura – Kadakola lines at the earliest.
KPTCL KPTCL Mail dated 26.06.2018:
1. ---Pending.
2. Auto Reclosure enabled for 220kV Bastipura Lines at Kadakola end. Power Grid has been
requested to enable AR for Kadakola lines at Bastipura Sub Station. ---Completed.
Pending
Annexure-II
Page 31 of 47
74/I/1 Complete outage of 220 kV
Sedam Substation
01-04-2018 at
19:56hrs
Triggering incident was fault in 220 kV Sedam-Tandur
line. 220 kV Sedam-Shahapur, 220 kV Sedam-RTPS lines -
1&2 and 220 kV Sedam-Tandoor line tripped from RTPS,
Shahpur and Tandoor. Tripping of incoming lines to
Sedam caused shut down at Sedam Sub Station resulting
in complete outage of the station.
KPTCL to adopt the following VT fuse-fail logic for all 220 kV
lines emanating from Sedam:
“Under VT fuse fail condition, distance protection shall
normally be kept blocked. However, upon detection of a fault
(sensed by negative sequence component), blocking of
distance protection shall give rise to operation of its inherent
Over-Current protection set with a definite time delay of say,
500 msec”.
KPTCL KPTCL Mail dated 26.06.2018:
Attended in all 220kV bays at Sedam.
Pending
74/I/2 Complete outage of 220 kV
Ambewadi station
02-04-2018 at
13:46hrs
Loss of supply occurred to 220 kV Ambewadi station due
to tripping of 220kV Nagzhari-Ambewadi line-2 (Source)
from Nagzhari power station. After bus dead, Ambewadi-
Ponda lines – 1 & 2 were hand-tripped. In antecedent
conditions, 220kV Ambewadi - Nagjheri ckt-1, 220kV
Ambewadi-Narendra Ckt-1 &2 were out of service.
1). KPTCL to review operation of SPS at NPH for proper
functionality and changed network conditions (reduction of
generation with tripping of evacuating lines) and put it into
service at the earliest.
2). KPTCL to furnish equipment failure report of the current
incident (R-phase CT in Nagjheri – 1 bay at Ambewadi SS) to
PSE&TD Division of CEA with a copy marked to SRPC.
KPTCL Yet to be informed Pending
74/II15 Multiple Trippings at 400/220kV
Guttur station
21-04-2018 at 12:50
hrs
Triggering incident was fault in 220 kV Davanagare -
Shimoga line. Bus bar protection operated at Guttur
resulting in tripping of all the connected elements. 220
kV Guttur was on single bus operation due to CVT
problem in Bus-2.
KPTCL to put double-bus operation at their 220 kV Guttur
substations by attending to Bus-2 CVT problem.
KPTCL Yet to be informed Pending
21-04-2018 at 12:55
hrs
21-04-2018 at 13:33
hrs
yet to be informed PendingTripping of 400 kV Nelamangala-
Bidadi line-1&2 and 400/220 kV
ICT-3 at Nelamangala
Mal-functioning of LBB relay provided on the 400 kV side
of ICT-3 resulted in Bus-B tripping at Nelamangala
KPTCL to furnish a detailed action taken report for the subject
trippings including remedial measures taken.
KPTCL74/II/16
Annexure-II
Page 32 of 47
49/I/3 Complete outage of 220kV
Ambewadi Substation of KPTCL
29.10.2015 at 14:34
hrs
220kV Nagjheri-Ambewadi line-1 tripped at 13:33 hrs
due to B phase to earth fault. Ambewadi was radially fed
from Nagjheri power station through 220kV Nagjheri-
Ambewadi line-2. Tripping of this line caused 220kV Bus
shut down at Ambewadi and remaining lines and
transformers were hand tripped
1. KPCL to provide A/R on all 220 kV lines emanating from
Nagjheri PH.
2. KPTCL to provide A/R on all 220 kV lines emanating from
Ambewadi SS.
KPCL/ KPTCL KPTCL Mail Recieved dated 22-11-2017:
1. coordination of KPCL has been requested for enabling AR lines terminated to Nagajari.
2. AR will be enabled at Ambewadi end for lines other than Ponda and Xeldom lines during
retrofitting of Back Up protection by Distance protection relay at Ambewadi.
KPTCL Mail dadted 16.12.2017 & Review Meeting dated 19.12.2017:
1. KPTCL informed that Coordination of KPCL has been requested for enabling AR lines
terminated to Nagajari.
--- Pending
2. KPTCL informed that AR would be enabled at Ambewadi end for lines other than Ponda and
Xeldom lines during retrofitting of Back Up protection by Distance protection relay at Ambewadi.
-- Pending
Pending
Status informed during Special Meeting held on 03.06.2016:
1. KPTCL informed that the matter had been taken up with concerned Line Operation and
Maintenance wing to carry out corridor clearance and maintenance as per schedule to avoid
frequent line faults in this corridor. A letter had also been addressed to Chief Engineer,
Bhagalkot zone, to ensure lines in & around Kali complex are maintained in healthy condition. ---
Completed
2. KPTCL assurd that the final modified SPS would be implemented at Nagjheri PH at the earliest.
------ Pending
3. KPCL informed that Nagjhari- Kodasalli Lines 1 & 2 had been kept in service since 23.05.2016
@ 08.06hrs.
--- Completed
KPTCL Mail received dated 28-06-2016:KPTCL Mail dated 16.12.2017:
1) & 3). --- Completed.
2). Proposed revision in existing SPS scheme is already submitted to SRLDC/SRPC., yet to be
discussed and approved by the SRPC forum --- Pending
Review Meeting dated 19.12.2017:
2. The SPS proposed by KPTCL was discussed and the PCSC forum suggested certain changes for
suitable incorporation. KPTCL agreed to look into the same and assured that the modified SPS
would be furnished by January, 2018.
Complete outage of 220 kV
Nagjheri power station and 220
kV Ambewadi substation of
KPTCL
Pending 1. To avoid tripping of transmission lines on transient faults,
KPCL/ KPTCL is recommended to carry out periodic patrolling
of lines, and ensure their proper maintenance by carrying out
jungle/ bushing clearance and trimming of tree branches
within the RoW of transmission lines as per the SRPC
transmission line patrolling guidelines (available under the
menu item "All Uploads/ Operation/ Miscellaneous/
Transmission Line Patrolling Protocol / Guidelines for
Southern Region" on SRPC website).
2. KPCL/ KPTCL to review operation of SPS at NPH for
functionality (reduction of generation with tripping of
evacuating lines) and healthiness.
3. KPCL to put 220 kV Kodasalli - Nagjheri D/C lines into
service if more than 200 MW generation from Kali Complex
(with Nagheri Contribution not less than 50 MW) is ensured
on sustained basis.
51/I/3 220kV lines from Nagjheri power house started tripping
from 11:00 hrs due to fault in lines. The sequence of
tripping is shown in SOE list. At 12:33 hrs, 220kV
Narendra-Ambewadi lines-1&2 got tripped which
resulted in loss of evacuation path to Nagjheri station
resulting in tripping of running Units and complete
outage at Nagjhheri power station. 220kV Ambewadi
station also got de-energized due to tripping of source
feeders i.e. 220kV Narendra-Ambewadi-1&2 and 220kV
Nagjheri-Ambewadi-1&2.
22-02-2016 at 12:36
hrs
KPCL/ KPTCL
Annexure-II
Page 33 of 47
Ambewadi Narendra line-2 tripped on fault and 220kV
ambewadi Narendra line-1 tripped due to over-loading.
Running Units at Nagjheri also tripped during the event
due to tripping of evacuating lines
1. KPCL to furnish a report on the reasons for Unit-6 tripping
at Nagjheri PH.
2. KPCL/ KPTCL to modify suitably the SPS at Nagjheri Power
House such that it would also factor in the over loading of
Ambewadi-Narendra lines.
3. KPCL to put 220 kV Kodasalli - Nagjheri D/C lines into
service if more than 200 MW generation from Kali Complex
(with Nagheri Contribution not less than 50 MW) is ensured
on sustained basis.
TANGEDCO mail dated 15.04.2017:
1) New Relay is tested and ready for replacement.Now all 5 units are in service.The relay will be
replaced when lesser units are in service. --- Pending
2.a)Steps are taken to renovate & mordernization of all the control panel into Numerical based
control panels. --- Pending
2.b) Since 230 KV indoor switchyard has no spare space providing dual CT`s is not fessible. --
Completed
3) Procurement of EL & DR is under progress. --- Pending
TANGEDCO mail dated 26.04.2017:
1) Check zone New Relay is replaced on 17.04.2017 -- Completed.
2. --- Pending
3. --- Pending
TANGEDCO mail dated 13.12.2017:
2).P & C wing gives clearance to TTPS to procure the Bus bar protection relays and protection
relays and SER / DR system vide Lr.CE/P&C/SE/D/EEPC4/AEE3/F.TECH/D.27/17 Dated:
05.10.2017. To get administrative approval budgetary offer has bar protection relay from various
companies ----Pending
3). SRPC vide Lr: SRPC/SE- III/CEA/2017/6450/DT:27.10.2017 gives features of SER/DR.
Budgetary offer will be called for SER / DR having above features. ---Penidng
Review Meeting dated 19.12.2017:
2) & 3) The issue was discussed and TANGEDCO was asked to provide time-line for implementing
the recommendations.
Mail dated 29.01.2018:
Procurement work is under progress and will be completed by December 2018.
PendingKPCL/ KPTCL18-03-2016 at 14:40
hrs
Failure of Bus Section-I Y-ph CT resulted in operation of
bus-bar protection for Bus Sections -I & II. Running
Units#1, 4 and 5, 230 kV Kayathar, 230kV Kudankulam,
230kV Sterlite, Station Transformer-1, 2 & 3 got tripped
during the incident. Unit – 2 & 3 were not in service.
TANGEDCO1. TANGEDCO to replace existing Check-Zone relay with a new
one possessing required performance.
2. TANGEDCO to take steps to provide numerical busbar
protection at their 220 kV Tuticorin TPS. TANGEDCO may also
explore providing dual CT’s (on either side) for all B/S
breaakers at the time of commissioning of numerical BBP, if
there were no space constraints.
3. TANGEDCO to take steps to provide for standalone Event
Logger (EL) and standalone Disturbance Recorder (DR) with
automatic downloading facility to a centralized server.
Tamil Nadu
25-01-2017 at 22:36
hrs
Tripping of running Units &
230kV feeders at Tuticorin TPS of
TANGEDCO
(Gen Loss: 640 MW)
53/I/3
62/II/7
KPTCL Mail received dated 28-06-2016:
Modifications to be carried in Nagzari SPS logic is submitted to SRLDC/SRPC for verification and
approval
Status received vide KPCL mail dated 14.06.2017:
1. Tripped since there was evacuation problem and there were only two lines NA-1 and NA-2 ----
Completed
2. Will be reviewed in consultation with EE(RT), KPTCL, Hubli. --- Pending
3. Both the lines are in charged condition. --- Completed.
KPTCL Mail Recieved dated 22-11-2017:
2. Proposed revision in existing SPS scheme is already submitted to SRLDC/SRPC., yet to be
discussed and approved by the SRPC forum. --- Pending
KPTCL Mail dated 16.12.2017:
Pending
Complete outage of 220kV
Ambewadi station of KPTCL and
220kV Nagjheri of KPCL
Annexure-II
Page 34 of 47
TANTRANSCO MAIL DATED 22.05.2018 & 08.06.2018:
230kV Othakalmandapam - Myvadi feeder replacement of kundha conductor with Zebra and
tower replacement work has been sanctioned. Work will be taken up. Timeline: June-2018.
TANTRANSCO Mail received on 19-02-2016 and 24-03-2016:
Revision of Bus Bar Protection setting was carried out. The stabilizing voltage setting was raised
from 410 to 450 volts. After completing the necessary test, the bus bar protection put in to
service on 29.12.2015.
Mail Received on 27-04-2016 ,16-06-2016,25-07-2016 & 24-09-2016:
Revision of Bus Bar Protection setting was carried out. After completing the necessary test, the
bus bar protection put in to service on 29.12.2015.
Mail received on 10-11-2016 & 20.12.2016:
Provision of Bus Coupler bay arrangement was included in the Upgradation works proposed and
the same was sanctioned by MoP through PSDF.
Numerical relay allotted and being commissioned.
Mail received on 20-02-2017:
Numerical BBP relay was commissioned on 02.02.2017
Status received vide mail dated 12.04.2017 & 01.06.2017 & 15-06-2017:
Numerical BBP relay was commissioned on 02.02.2017.
Provision of Bus Coupler bay arrangement was included in the Upgradation works proposed and
the same was sanctioned by MoP through PSDF.
Status received vide mail dated 04.08.2017:
05-09-2015 at 14:04
hrs
Complete outage of 230kV Palladam, 230 kV
Othakalmandapam S/s, 230 kV Coimbatore S/s, 230 kV
Thudialur and 230 kV Sadayapalayam S/s
TANTRANSCO to take suitable measures like installing more
stub-towers along 230 kV OK Mandapam – Myvady line to
avoid excessive sag due to over-loading.
Busbar protection got operated for a fault in 230kV
Mywadi-Anaikadavu line
TANTRANSCO Mail received on 19-02-2016, 24-03-2016 and 27-04-2016:
230kV Othakalmandapam - Myvadi feeder will be made LILO at Kongal Nagar. Line restringing
will be carried out along with the above proposal.
Mail Received on 20-05-2016 ,16-06-2016,25-07-2016 & 24-09-2016:
230kV Othakalmandapam - Myvadi feeder will be made LILO at Kongal Nagar. Line restringing
will be carried out along with the above proposal.
Status received vide mails received on 10-11-2016 & 20.12.2016 & 12.04.2017 & 01.06.2017 &
15-06-2017 & 04.08.2017:
230kV Othakalmandapam - Myvadi feeder will be made LILO at Kongal Nagar. Line restringing
will be carried out along with the above proposal.
TANTRANSCO mail dated 18-09-2017 & 31-10-2017:
Othakalmandapam - Myvadi feeder will be made LILO at Kongal Nagar. Line restringing will be
carried out along with the above proposal.
Status received vid email dated 12-12-2017:
Othakalmandapam - Myvadi feeder replacement of kundha conductor with Zebra and tower
replacement work has been sanctioned. Work will be taken up.
Review Meeting dated 19.12.2017:
TANTRANSCO informed that 230 kV OK Mandapam - Myvady feeer was LILOed at Anaikadavu on
06.11.2017. Further replacement of the existing Kundah condductor with Zebra has also been
taken up, and is targeted to be completed by June, 2018.
TANTRANSCO mail dated 25-01-2018:
230kV Othakalmandapam - Myvadi feeder replacement of kundha conductor with Zebra and
tower replacement work has been sanctioned. Work will be taken up. Timeline: June-2018.
TANTRANSCO PendingTANTRANSCO to examine the feasibility of providing two
main-zone operation for bus bar protection by exploring
various alternatives like replacing existing bus-coupler CB
with a hybrid bus-coupler CB that comes with inbuilt CT,
replacing existing BBP relay with another suitable relay that
supports two main-zone operation, and implement the same.
Complete outage of 230kV
Mywadi station of TANTRANSCO
48/I/1 PendingDisturbance in 220kV Tamilnadu
system
TANTRANSCO
21-12-2015 at 6:28
hrs
50/I/3
Annexure-II
Page 35 of 47
Status received vide mail dated 18-09-2017 & 31-20-2017:
Numerical BBP relay was commissioned on 02.02.2017. Provision of CT in Bus Coupler bay is
arranged and zone segregation will be provided.
Status received vid email dated 12-12-2017:
Numerical BBP relay was commissioned on 02.02.2017. Provision of CT in Bus Coupler bay has
been allotted. Zone segregation will be provided after commissioning of CT.
Review Meeting dated 19.12.2017:
TANTRANSCO informed that the recommendation would be complied with by March, 2018.
TANTRANSCO Mail received on 25-01-2018:
Provision of CT in Bus Coupler bay is arranged and zone segregation will be provided. Timeline:
March-2018.
TANTRANSCO MAIL DATED 22.05.2018 & 08.06.2018:
Bus coupler bay equipments allotted will be commissioned by Aug 2018
Busbar protection got operated for a fault in 230kV
Mywadi-Anaikadavu line
TANTRANSCO PendingTANTRANSCO to examine the feasibility of providing two
main-zone operation for bus bar protection by exploring
various alternatives like replacing existing bus-coupler CB
with a hybrid bus-coupler CB that comes with inbuilt CT,
replacing existing BBP relay with another suitable relay that
supports two main-zone operation, and implement the same.
Complete outage of 230kV
Mywadi station of TANTRANSCO
21-12-2015 at 6:28
hrs
50/I/3
Annexure-II
Page 36 of 47
TANTRANSCO mail received on 25-01-2018:
1) Commissioning of Bus Coupler CT, Extended Bus with Additional Bus Coupler is under
progress. Timeline: June-2018.
2) Numerical BBP commissioned on 29.08.2017 to enable Bus seggregation.
3) Providing Re-Trip feature for LBB will be studied.
TANTRANSCO MAIL DATED 22.05.2018 & 08.06.2018:
Providing new Bus coupler bay involes bay shifting work.work awarded and under progress.
Time line. Dec2018.
Mail recieved on 25-07-2016 & 24-09-2016:
TANTRANSCO: Auto Transformer-2 HV side Bus isolator 'C'-phase support insulator of 230kV
Southern Bus was replaced and Bus Bar Protection scheme was restored on 12.05.2016.
Status received vide mails received on 10-11-2016 & 20.12.2016 & 12.04.2017 & 01.06.2017 &
15-06-2017 & 04.08.2017 & 18.09.2017:
CT is not available in the Bus Coupler bay for zone segregation. CT latch relay is to be provided
for all bays for zone segregation.
Status received vide mails received on 31-10-2017 & 12-12-2017:
Numerical Bus bar protection panel allotted and will be commissioned with zone segregation..
Review Meeting dated 19.12.2017:
TANTRANSCO informed that Numerical BBP would be commissioned by March, 2018.
TANTRANSCO mail received on 25-01-2018:
Commissioning of Numerical Bus bar protection is under progress. Zone segregation will be
ensured. Timeline: March-2018.
TANTRANSCO mail received on 24-03-2016:
CMR relay for extending LBB protection was released and LBB extended from Distance
Protection relay directly. CT is not available in the Bus Coupler bay for zone segregation.
However, during commissioning of third ICT, Bus section Breaker will be provided for zone
segregation. Numerical BBP relay will be provided.
Status received vide mails recieved on 27-04-2016 and 20-05-2016 ,16-06-2016, 25-07-2016, 24-
09-2016,10-11-2016 & 20.12.2016 & 12.04.2017 & 01.06.2017 & 15-06-2017:
1 & 2) CT is not available in the Bus Coupler bay for zone segregation. However, during
commissioning of third ICT, Bus section Breaker will be provided for zone segregation. Numerical
BBP relay will be provided.
Status received vide mail dated 04.08.2017:
1 & 2) Contract awarded for providing third ICT & Bus modification works to accomodate bus
coupler bay. Numerical BBP relay has been provided and tesing under progress.
Status received vide mail dated 18.09.2017:
1 & 2) Contract awarded for providing third ICT & Bus modification works to accomodate bus
coupler bay. Numerical BBP relay has been provided and tesing under progress.
Status received vide mail dated 01.11.2017:
1 & 2) Contract awarded for providing third ICT & Bus modification works to accomodate bus
coupler bay.
55/I/1
(GD)
Complete outage of 230 kV
Gummidipoondi Station of
TANTRANSCO
12-05-2016 at 12:15
hrs
Flashover of Auto Transformer- 2 HV
B-phase Isolator supporting insulator of 230kV Southern
Bus occurred at Gummidipoondi station. At the time of
fault, Bus bar protection relay was not in service for pre-
commissioning testing of Auto Transformer-2. All
feeders got tripped due to operation of zone-2
protection from remote ends.
TANTRANSCO to take steps to provide double-bus operation
at their 230 kV Gummidipoondi SS.
TANTRANSCO Pending
51/I/1
(GD)
PendingTANTRANSCO 1. TANTRANSCO to provide split-bus operation with bus
sectionalizer CB for their 230 kV Madurai (Chekanurani) SS.
2. TANTRANSCO to provide two main-zone operation for the
numerical BBP that is being commissioned.
3. TANTRANSCO to examine the feasibility of providing Re-
Trip feature for the LBB protection, and accordingly take steps
for implementing the same.
Fault had occurred in 230kV Madurai-Sembatty line. Trip
from distance relay was not extended to breaker due to
protection DC fail. LBB protection got operated resulting
in a busbar trip at 230kV Madurai substation. All
elements got tripped as there is a single bus operation at
230kV Madurai S/s
19-01-2016
at 11:56 hrs
Complete outage of 230kV
Madurai S/s (Chekanaurani) of
TANTRANSCO
Annexure-II
Page 37 of 47
TANTRANSCO MAIL DATED 22.05.2018 & 08.06.2018:
Numerical Busbar protection relay commissioned on 14.05.2018
55/I/1
(GD)
Complete outage of 230 kV
Gummidipoondi Station of
TANTRANSCO
12-05-2016 at 12:15
hrs
Flashover of Auto Transformer- 2 HV
B-phase Isolator supporting insulator of 230kV Southern
Bus occurred at Gummidipoondi station. At the time of
fault, Bus bar protection relay was not in service for pre-
commissioning testing of Auto Transformer-2. All
feeders got tripped due to operation of zone-2
protection from remote ends.
TANTRANSCO to take steps to provide double-bus operation
at their 230 kV Gummidipoondi SS.
TANTRANSCO Pending
Annexure-II
Page 38 of 47
The issue was discussed in PCSC-58 meeting held on 18.10.2016, when PCSC forum agreed to de-
link the implementation of the Item from the scope of Protection Audit Recommendations
(PAR), and pursue it as part of PCSC Recommendations.
Status received vide mails dated 10.01.2017 & 12.04.2017 & 01.06.2017 &15-06-2017 &
04.08.2017 & 18.09.2017 & 31-10-2017& 12-12-2017:
Different make Relays will be provided for Main-I & II relays at Sunguvarchatram end in a phased
manner.
Review Meeting dated 19.12.2017:
TANTRANSCO informed that the recommended works of providing different make Relays for
Main-I & Main-II are targeted to be completed by September, 2018.
TANTRANSCO mail received on 25-01-2018:
Different make Relays will be provided for Main-I & II relays at Sunguvarchatram end in a phased
manner. Timeline: September-2018.
TANTRANSCO MAIL DATED 22.05.2018:
TANTRANSCO informed that the recommended works of providing different make Relays for
Main-I & Main-II are targeted to be completed by September, 2018.
TANTRANSCO MAIL DATED 08.06.2018:
provision of Different make Relays for Main-I & Main-II will be completed by September, 2018.
14-09-2016 at
11:13Hrs
Bus Bar Protection (Zone-2) of 230 kV Bus-B got operated
at Alamathy Station during fault in 230 kV Alamathy-
Korattur feeder.
15-09-2016 at 22:14
hrs
Bus Bar Protection (Zone1) of 230kV Bus-A got operated
at Alamathy Station during fault in 230 kV Alamathy-OPG-
1 feeder.
58/II/17 Multiple tripping at 230 kV
Alamathy Station
1. TANTRANSCO to check the healthiness of BBP relay by
conducting stability test, and take appropriate remedial
action like increasing voltage settings, ensuring the
healthiness of CT’s, using CT’s with similar characteristics
(equal saturation effects & equal winding resistances) etc. at
their 230 kV Alamathy SS.
2. TANTRANSCO to replace the existing high-impedance BBP
relay with its low-impedance/ numerical variant so as to
accommodate variation in CT characteristics at their 230 kV
Alamathy SS.
Mail received on 10-11-2016 & 20.12.2016:
1. The Bus Bar Protection scheme will be tested for healthiness including the CT circuits.
2. High impedance BBP relay will be replaced by Numerical relay.
Status received vide mails dated 10.01.2017 & 12.04.2017 & 01.06.2017 & 15-06-2017:
1. The Bus Bar Protection scheme was tested for healthiness including the CT circuits. AREVA
make CTs in Alamathy SS are having different kneepoint voltage for the cores. CT cores of higher
knee point voltage has been choosen for BBP in 230kV Korattur, 230kV OPG-1 & 230kV OPG-2
feeders on 29.11.2016. ---- Completed.
2. High impedance BBP relay will be replaced by Numerical relay. --- Pending,
Status received vide mails dated 04.08.2017 & 18.09.2017 & 31-10-2017 & 12-12-2017.
1. ---- Completed
2. High impedance BBP relay will be replaced by Numerical relay. --- Pending
Review Meeting dated 19.12.2017:
2) TANTRANSCO informed that Numerical BBP would be provided by April, 2018 --- Pending
TANTRANSCO mail received on 25-01-2018:
1. --- Complied.
2. High impedance BBP relay will be replaced by Numerical relay. Timeline: April-2018.
TANTRANSCO MAIL DATED 22.05.2018 & 08.06.2018:
2.Numerical BBP relay will be provided. Timeline: Sep-2018.
TANTRANSCO Pending
58 Different type and Make of distance protection relays to be provided for Main-I & Main-II protection for 230kV feeders at 400 kV Sunguvarchathiram & 230 kV
Sunguvarchathiram Substation [Carry-Over from Protection Audit Recommendations]
TANTRANSCO Pending
Annexure-II
Page 39 of 47
64/1/4 Complete outage of North
Chennai TPS STG-1
26-03-2017
at 23:14hrs
Tripping of evacuating lines due to fault led to tripping of
running Unit at NCTPS Stg-1
1. TANTRANSCO to take steps to complete insulator
replacement works on the 230 kV lines owned by them in
NCTPS area within 6 months.
2. TANTRANSCO to take steps to implement A/R on all 230 kV
lines emanating from NCTPS-I at the earliest.
TANTRANSCO Status received vide mails dated 04.08.2017 & 18.09.2017 & 31-10-2017:
1. All the Porcelain insulators were replaced with Polymer insulators in 230kV NCTPS-I -
Tondiarpet feeders - 1 & 2.
---- Completed
2. AR will be implemented on all 230kV lines emanating from NCTPS-I. --- Pending
Status received vid email dated 12-12-2017:
1. Completed
2. The scheme needs modification to enable AR, since AR was not envisaged for this station
during commissioning. AR will be implemented on all 230kV lines emanating from NCTPS-I
within six months. --- Pending
Review Meeting dated 19.12.2017:
2) TANTRANSCO informed that A/R would be implemented on all 230 kV lines emanating from
NCTPS-I by June, 2018.
TANTRANSCO mail received on 25-01-2018:
1. Complied.
2. The scheme needs modification to enable AR, since AR was not envisaged for this station
during commissioning. AR will be implemented on all 230kV lines emanating from NCTPS-I
within six months. Timeline:June-2018.
Pending
TANTRANSCO MAIL DATED 22.05.2018:
2. The scheme needs modification to enable AR, since AR was not envisaged for this station
during commissioning. AR will be implemented on all 230kV lines emanating from NCTPS-I
Timeline:Sep -2018.
TANTRANSCO mail received on 08-06-2018:
1. Complied.
2. The scheme needs modification to enable AR, since AR was not envisaged for this station
during commissioning. AR will be implemented on all 230kV lines emanating from NCTPS-I
Timeline:Sep -2018.
73/I/6 Complete outage of 400 kV
Sriperumbudur station
24-03-2018 at 18:01
hrs
There was HV side Y-phase CT failure of 400/ 230 kV ICT-
2 at Sriperumbudur. This resulted in tripping of all
connected feeders and ICTs.
1) TANTRANSCO to ensure healthiness of 400 kV side CB of
ICT-3 (CB-1752) and integrity of its LBB protection.
2) TANTRANSCO to furnish equipment failure report of the
current incident (CT blast) to PSE&TD Division of CEA with a
copy marked to SRPC.
3) TANTRANSCO to refer the instant case of PRV operation of
ICT-1 to its OEM, and take appropriate action based on their
advice.
TANTRANSCO TANTRANSCO MAIL DATED 22.05.2018 & 08-06-2018:
1. 96 relay operation checked and scheme operation ensured.
----Complied
2. Failure Report will be sent to CEA
----Pending
3.Issue will be refered with OEM and appropriate action will be taken
----Pending
Pending
Annexure-II
Page 40 of 47
Kerala
Annexure-II
Page 41 of 47
KSEB Mail received vide dated 17.01.2017:
1. 110 kV bus bar protection progressing ----Pending
2. Connection of 220kV earth mat and 110 kV plate earthing system completed.---- Completed
3. Redundancy of 110V DC system in progress. Complete independent redundancy is not
practical for the time being. 48 V DC redundancy was already there. ----Pending
4. Instead of stand alone event logger, SCADA system of 110 kV feeder is expected to be
completed by the end of 2017. SCADA system of 220kV side will be taken up after that ----
Pending
KSEB Mail received vide dated 18.09.2017:Status received vide mail dated 12-12-2017:
1. Detailed engineering of the scheme has been completed. Material procurement is in progress.
---Pending
2.,3. ---- Completed
68/II/12 Tripping of 400 kV NPS – Nellore-
PG D/C line
08-10-2017
at 18:58 hrs
Lines tripped during a fault on 400 kV Nellore-PG –
Vijayawada line-2
1. For the 400 kV Nellore-PG – Vijayawada line, PGCIL (SR-I) to
investigate the reasons for 3-ph tripping of Main-CB upon
detection of the fault without trying for A/R and operation of
Stub/ Tee protection at the time of Tie-CB A/R attempt at
Vijayawada end during instant trippings, and furnish remedial
measures taken to address the issues involved.
2. PGCIL (SR-I) to test the recently commissioned CSD’s at
their 400 kV Nellore-PG SS at the earliest and ensure their
correct operation.
3. PGCIL (SR-I) to configure DR’s and EL’s of Distance
Protection Relays at Nellore-PG with suitable LEGENDs for
indicating operation of type of protections (like Zone-1, Zone-
2, Zone-3, DEFR, OVR-I, OVR-II, etc.).
PGCIL (SR-I) PGCIL-SR1 Mail dated 15.12.2017 & Review Meeting dated 19.12.2017:
1. --- Pending.
2. Due to CSD contractor problem CB Y-pole reclosed & defective contactors replaced & wiring
problem in CSD rectified on next day --- Completed.
3. NPS end DR & EL configured as suggested. --- Completed.
PGCIL (SR-I) mail dated 20.06.2018:
1. Line A/R scheme checked at VJA end during the S/D on and A/R scheme is operating correctly
for both Main & Tie CBs, A/R sucessful at both ends during the trippings on 03.05.2018. At VJA
end Stub protection checked & found relay faulty & the same was replaced with spare relay on
22.03.2018 during line S/D.
Pending
74/III/4Tripping of 400 kV
Maheshwaram - Narnoor line
03-04-2018 at 12:28
hrs
B-phase to earth fault occurred in line. Auto-reclose was
successful at Maheshwaram and Auto reclose was not
attempted at Kurnool (AP).
PGCIL (SR-I) to furnish a detailed report on the reasons for
the tripping of the line including remedial measures taken. PGCIL (SR-I)
PGCIL (SR-I) mail dated 20.06.2018:
The protection operation at Maheshwaram (POWERGRID) end is in order. Ony permissive PLCC
code was transmitted from POWERGRID end.
At Narnoor (APTRANSCO) en, NO DT signal receive was recorded in DR (from DR & Eluploaded by
AP in SRLDC trip portal. The EL list uploaded by AP is BCU internal events. The BCU was recently
commissioned by APTRANSCO under SAS upgradation. The spurious DT signal high in BCU might
be wrong wiring/configuration of BCU.
Pending
74/III/11Tripping of Ramagundam -
Hyderabad line-4
08-04-2018 at
05:16hrs
Y-phase to earth fault. Auto-reclose was successful at
Ghanapur end. Ramagundam end did not attempt auto-
reclose as there was operation of distance protection
Zone-2 leading to tripping of breaker.
For the line under consideration, the following shall be
carried out by NTPC-Ramagundam, in coordination with PGCIL
(SR-I):
(i) End-to-end communication for DT/ permissive & other
signals may be ensured by testing at both the ends.
(ii) Healthiness of PLCC system components (hardware and
software) at both ends shall be checked and faulty
components shall be repaired/ replaced.
PGCIL (SR-I)
PGCIL (SR-I) mail dated 20.06.2018:
PLCC end to end testing, Relay testing completed & verified and found ok- on 21.02.2018 during
line S/D. However same will be checked during the next shutdown.
Pending
73/II/8 Tripping of 400 kV Pavagada-
Tumkur line-1, 400/ 220 kV ICT-
1&2 at 400 kV Pavagada SS
16-03-2018 at 14:18
Hrs
Multiple trippings occurred during charging of 400 kV
Pavagada-Tumkur line-2.
1) PGCIL (SR-II) to review SOTF settings at Tumkur end on
Tumkur – Pavagada lines considering the least expected fault
current levels.
PGCIL (SR-II) Yet to be Informed Pending
PendingKSEB to take steps to provide the following at their 220/ 110
kV Kalamassery SS:
1. Busbar protection at 110 kV level
2. Connecting 220 kV and 110 kV sides on to a common
earthmat
3. Redundant DC supply for both protection (220 V) and
communication (48 V) applications
4. Stand-alone Event Logger
23-08-2016
at 11:20 hrs
KSEBComplete outage of 220 kV
Kalamassery Substation
58/I/1
(GD)
Triggering incident was conductor snapping in 110 kV
Kalamassery- Kaloor feeder
PGCIL (SR-I) & PGCIL (SR-II)
Annexure-II
Page 42 of 47
73/II/9 Tripping of HVDC Talcher-Kolar
Pole-1.
17-03-2018 at 15:12
hrs
Talcher – Kolar Pole-1 tripped due to mal operation of
DC protection system at Talcher end and Emergency
Switch OFF (ESOF) signal received at Kolar end.
PGCIL (SR-II) to furnish a detailed report on the instant
tripping explaining clearly the reasons for repeated voltage
recovery sequences, reasons for Pole-2 going into ground
return mode while attempting Pole-1 de-block around 20:28
hrs, and non-operation of SPS
(i) at around 15:12 hrs when the Pole-1 was blocked, and
(ii) at around 20:28 hrs when Pole-2 went into ground return
mode.
PGCIL (SR-II) Yet to be Informed Pending
73/III/4 Tripping of 400 kV ILFS-
Nagapattinam PS line-1.
28-03-2018 at 10:32
Hrs
R-phase to earth fault had occurred in line. Auto-reclose
attempt could not be validated with submitted DR of
Nagapattinam end.
PGCIL (SR-II) to furnish a report on the reasons for A/R non-
operation, and the remedial action taken to rectify the same.
PGCIL (SR-II) Yet to be Informed Pending
74/II/20 Tripping of 400/ 220 kV ICT-2 at
Somanahalli
25-04-2018 at
15:23hrs
ICT-2 got tripped due to mal-operation of Buchholtz’s
relay.
1). PGCIL (SR-II) to take steps to replace the faulty PNRV’s of
the ICT’s with the proposed reverse flow blocking devices at
the earliest at their Bidadi, Somanahalli, and Pavagada
stations.
2). PGCIL (SR-II) to configure Event Loggers (EL’s) to capture
events msec level at their Somanahalli SS.
PGCIL (SR-II) Yet to be Informed Pending
Annexure-II
Page 43 of 47
Others
PendingNPCIL (MAPS)B-phase CT failure occurred in 230 kV S.P.Koil - MAPS
line-1. Busbar protection got operated at SP.Koil station.
All elements except 230kV Oragadam and 230kV
Kalivandapattu got tripped at 230kV S.P.Koil station. ‘Y’
phase CT and support insulators also got damaged.
1.MAPS to furnish a detailed report on the tripping of SP Koil
– MAPS lines 1 & 2 at MAPS end with focus on the correctness
of the settings of Main-I & Main-II relays (for primary & back-
up protections) on both the lines.
2.MAPS to take steps to provide down-loading facility for DR
& EL from Main-I & Main-II relays on all 230 kV lines
emanating from MAPS.
3.MAPS, in co-ordination with SP Koil, to carry out PLCC end-
to-end testing, on SP Koil – MAPS lines 1 & 2, and ensure
healthiness of PLCC communication & carrier-aided
protection.
4.MAPS to put in service Auto-Reclosure feature on all four
230 kV lines emanating from MAPS by June, 2016.
54/I/1 02-04-2016 at 17:08
hrs
Status revided vide MAPS mail dated 06.12.2016;
1. The settings given by M/s TANTRANSCO were adopted for Main –I & Main- II relays for both
the lines. The same settings were verified to be same. Subsequently calibrated was done and
no drift was observed. --- Completed
2. From May 2016 onwards, the DR, EL and trip report are being sent by mail to SRLDC,
Bengaluru by MAPS. --- Completed
3. Monthly maintenance of PLCC equipments is being done by M/s TANTRANSCO. At present
PLCC telephone is not working, it is being followed up. --- Completed
4. CVTs are planned to be procured from M/s TANTRANSCO by the end of February 2017 and
A/R will be implemented for all the lines emanating from MAPS by July-2017 as discussed in the
current SRPC meeting on 25/11/2016. --- Pending
Status received vide MAPS mail dated 06.12.2016 & Review Meeting dated 19.12.2017;
The CVTs procurement is in progress and the scheme (A/R) would be implemented before 31-03-
2018.
Complete outage of 230 kV
S.P.Koil Station of TANTRANSCO
Annexure-II
Page 44 of 47
62/III/2 Tripping of 400 kV Kaiga-Guttur
line-1
06-02-2017
at 05:01 hrs
B-phase to earth fault. Line did not auto-reclose at Kaiga
end.
1. KGS to properly configure all relays DR’s time scale for a
post-triggering period of 2 sec to capture events such as
complete A/R operation.
2. KGS to ensure time-synchronization of all protection relays
with GPS in their 400 kV switchyard.
NPCIL (KGS) Status received vide mail dated 29.11.2017 & Review Meeting dated 19.12.2017:
1. All 400kv transmisisonlines relays DR time scale for a post-triggering period of 2 sec is
implemented. ----Completed
2.Time-synchronization for all lines protection relays (M1 &M2) with GPS in their 400 kV
switchyard is being implemeneted. Scheme design is in process. ECD-April-2018 ---- Pending
NPCIL (KGS) Reply during Special Meeting at Kaiga dated 22.06.2018:
2. KGS agreed to ensure time-synchronization of all protection relays with GPS in their 400kV
swithcyard by Dec 2018. --- Pending
Pending
68/II/11 Tripping of 400 kV
K V KOTA - HNPCL lines – 1 & 2
29-09-2017 at 22:36
hrs
Line-1 tripped on R-E Zone-1 fault, and the Line-2 tripped
on Direct Trip receipt at KV Kota end
1. HNPCL to ensure time sync of all of their protection relays
with GPS, and to configure corresponding DR’s for post
triggering time of 2 sec.HNPCL to configure DEF operation
only when Distance relay does not sense the fault.
2.HNPCL to ensure healthiness of A/R scheme implemented
on all 400 kV lines at their station.
3.HNPCL to provide priority A/R scheme for 400 kV Tie-CB’s
with s suitable dead-time of say 2 sec.
4.HNPCL to revise PDR timing as 1.5 sec till implementation of
A/R for Tie-CB’s after which it shall be further revised to 2.5
sec.
5.HNPCL to implement following OVR-I gradings for the 400
kV lines emanating from their station:
Kalpaka Line-1 7.35 A 111%, 10 sec
Kalpaka Line-2 7.35 D 110%, 8 sec
KV Kota Line-1 246 B 111%, 9 sec
HNPCL HNPCL Mail dated 11.01.2018:
1. Time synchronization of protection relays and BCU's with GPS completed. As per APTRANSCO
recommendations DEF has been switched off in line protection relays.
--- Pending
2. --- Pending
3. Line Tie CBs Priority closing has been implemented for all the lines. --- Pending
4. --- Pending
5. --- Completed
HNPCL Mail dated 12.05.2018:
CB close interlock gone to “self-check Fault” state during the AR cycle. Due to that AR gone to
lockout state. Breaker open state CB close interlock should be satisfied condition.Accordingly
the logic has been modiified.
Pending
69/I/1 Complete outage of 400kV TPCIL
station
25-10-2017 at 19:33
hrs
400 kV TPCIL-Nellore PS line-1 got tripped from TPCIL
end during fault in 400kV Nellore-Nellore PS line-2.
Running units at TPCIL got tripped due to loss of
evacuating line. 400kV Nellore PG - Nellore PS line-2 and
400kV TPCIL - Nellore PS line-1 were under shutdown.
TPCIL to configure DEF protection such that it remains in
blocked condition as long as Distance Protection is active, and
becomes active only when distance protection does not
pickup.
TPCIL Yet to be informed Pending
Annexure-II
Page 45 of 47
NLCIL Mail dated 18.01.2018:
1. Shut down was taken on 400kV Neyveli TS-II to Pugalur feeder on 18-01-18 to check the end-
to-end communication for DT/ permissive & other signals by testing at both the ends and to
check the healthiness of the PLCC system components.
The system was thoroughly checked and the missing loops in the relay circuit (Carrier send in
Main1 relay and Carrier receive in Main2 relay) were provided.NLCIL Mail dated 24.04.2018:
1. Completed.
2. The tripping of Pugalur feeder on 10-10-2017 at 23:54 hrs as per PCSC recommendation, the
Defective relay P437 was replaced with spare P437 relay and the settings were checked.The
spare relay replacement work carried out on 26& 27th March at the time shut down of Pugalur
feeder.
71/III/1 Tripping of 400 kV HNPCL- KV
Kota line-2
26-12-2017 at 12:34
hrs
R-phase to earth fault had occurred in line. Breakers at
HNPCL got tripped due to auto-reclose lockout and auto-
reclose was successful at KV Kota end.
HNPCL to furnish a report detailing the reasons for A/R non-
operation in the instant tripping, and remedial measures
taken to set right them.
HNPCL HNPCL Mail dated 12.05.2018:
CB close interlock gone to “self-check Fault” state during the AR cycle. Due to that AR gone to
lockout state. Breaker open state CB close interlock should be satisfied condition.Accordingly
the logic has been modiified.
Pending
72/III/5 Tripping of 400 kV HNPCL - K.V.
Kota line
02-02-2018 at 11:46
hrs
Tripped due to R-phase to ground fault. Line did not
reclose at HNPCL.
1. HNPCL to configure DEF protection such that it remains in
blocked condition as long as Distance Protection is active, and
becomes active only when distance protection does not
pickup.
2. HNPCL to ensure healthiness of A/R scheme implemented
on all 400 kV lines at their station.
HNPCL APTRANSCO maild ated 24.04.2018 & 24.05.2018:
To be attended by HNPCL
HNPCL maild ated 12.05.2018:
1....Pending
2.CB close interlock gone to “self-check Fault” state during the AR cycle. Due to that AR gone to
lockout state. Breaker open state CB close interlock should be satisfied condition.Accordingly
the logic has been modiified.
Pending
73/I/3 Complete outage of following
220kV stations of KPTCL
Narendra (KPTCL), Bidnal, SRS
Hubballi, Ambewadi Haveri,
Karwar, Belgaum, Chikkodi,
Soudatti, ML Pura, Athani,
Kudachi, Ghataprabha, MK Hubli,
NPH, Kodasalli and Kadra
08-03-2018 at 10:01
hrs
220kV Kaiga-kadra and 220kV Kadra-Kodasalli lines
tripped on backup over-rcurrent protection. 400/220kV
Narendra ICT tripped on over load protection. Running
units at Nagjhari and Kodasalli tripped due to non-
availability of evacuation lines. Cascaded tripping
occurred due to overloading of 220 kV network and
there was complete outage of several stations of KPTCL.
1). NPCIL (KGS) to use stipulated formats for furnishing FIR
and TR.
2). NPCIL (KGS) to configure DR’s & EL’s of all protection
relays at their 400 kV & 220 kV Kaiga GS for recording all
mandated protections.
NPCIL (KGS) NPCIL(KGS) Reply during Special Meeting at Kaiga dated 22.06.2018:
1.KGS agreed to use stipulated formats for furnishing FIR and TR
---- Completed
2.KGS agreed to include line backup protections in Main-I & Main-II within 2 months and
configure DR's and EL's of Main -I & II for recording all mandated protections --- Pending
Pending
73/I/4 Complete outage of 220kV
Kemar, MSEZ Bajpe, Kavoor,
Netlamandur (Puttur) and 400/
220 kV ICT-2 at UPCL
14-03-2018 at 18:45
hrs
Fault in 220 kV Kemar – Bajpe line-2 led to tripping of
220kV UPCL-Kemar Line-2 due to faulty LBB operation.
Subsequently, lnie faults on 220 kV Varahi – Kemar lines
and UPCL – Kemar line-1 led to complete outage of
220kV Kemar, MSEZ Bajpe, Kavoor, Netlamandur
(Puttur).
UPCL to provide re-trip feature for LBB protection of all
breakers at their 220 kV Udupi power plant.
UPCL Yet to be informed Pending
69/II/9 Tripping of 400 kV Neyvelli TS2 –
Pugalur and 400 kV Neyvelli TS2
(exp) – Pugalur line
10-10-2017 at 23:54
hrs
Protection at NLCTS-2 & NLCTS-2 Exp has sensed as R-Y-E
fault and given a 3 phase trip. At Pugalur end protection
has sensed fault as Y-N and B-N fault in 400kV Neyveli
TS2-Pugalur line & 400kV Neyveli TS2 EXP-Pugalur line
respectively. Breaker at Pugalur got tripped due to Direct
Trip receipt.
1.For the tripping of 400 kV NLC TS2 – Pugalur line, NLCIL to
investigate the reasons for sending of DT to Pugalur end, and
furnish an action taken report including remedial action taken
and setting right various LEGEND issues in DR & EL of
protection relays to PCSC forum.
2. For the tripping of 400 kV NLC TS2Exp – Pugalur line, NLCIL
to investigate the reasons for 3-ph tripping (detection of the
fault as Y-B-E) of the line from NLC TS2Exp end including
verifying pertinent settings of P437 relay (reference may be
made to explanation given by TPCIL in GD - I.1/ GD - I.2), and
furnish an action taken report including remedial action taken
and setting right various LEGEND issues in DR & EL of
protection relays to PCSC forum.
NLCIL Pending
Annexure-II
Page 46 of 47
73/III/3 Tripping of 400kV Kaiga-
Narendra line-2
18-03-2018 at 13:25
hrs
Narendra end auto reclose could not be attempted due
to direct trip receive from Kaiga. From EL of Kaiga, R-
phase Zone-1 trip and A/R lock out were observed.
NPCIL (KGS) to take steps to disable sending of DT to remote
ends upon 86X operation for any line protection operation at
its 400 kV KGS.
NPCIL (KGS) NPCIL (KGS) Reply during Special Meeting at Kaiga dated 22.06.2018:
KGS agreed to disable sending of DT to remote ends upon 86X operations for any line protection
operation at its 400kV KGS within one month. --- Pending
Pending
74/II/12 Tripping of 400 kV Bellary PS -
JSWEL line
16-04-2018 at 16:16
hrs
Main#2 (ABB REL 670) relay’s SOTF protection mal-
operated at JSWEL. DT sent to BTPS
1). It was noted from DR that there was an R-E fault at the
time of occurrence of above tripping, which might have
(wrongly) led to SOTF initiation; hence logic employed for
SOTF protection operation needed to be checked.
2). JSWEL was asked to check whether interlock with CB OPEN
status has been properly incorporated in SOTF logic.
JSWEL Yet to be Informed Pending
74/II/17 Tripping of 400 kV
Kalavindapattu - Vallur line- 1
23-04-2018 at 10:22
hrs
At Vallur station, tracking was observed in stack of CVT
while carrying out hot-line water washing of CVT in B
phase. This was suspected to have caused Over-voltage
in CVT secondary circuit. Direct trip was sent to
Kalavindapattu end.
• In this regard, NTECL-Vallur was asked to ensure that they
have kept time setting for OVR operation as 100 msec.
NTECL
(Vallur)
Yet to be Informed Pending
Annexure-II
Page 47 of 47
Sl.No. Element Name Outage date/time Revival date/time Reason for outage Sender/ Receiver Remedial Measures/ Actions taken
1 400KV-NARNOOR-SRISAILAM_LEFT_BANK-1 20-03-2018/17:53:00 20-03-2018/20:31:00
Ground Time Over
Current operated at
Srisailam
APTRANSCO/TSGENCO
TSGENCO:
Direct trip send wiring was done for the
ground time over current faults
APTRANSCO:
Feeder not tripped at Narnoor End.
2 400KV/220KV KOZHIKODE-ICT-3 01-04-2018/10:46:00 01-04-2018/14:18:00DIFFERENTIAL
PROTECTION ACTEDPGCIL (SR-II)
PGCIL (SR-II):
3 220KV-YERRAANDAHALLI-HOSUR_TN-1 19-04-2018/12:45:00 19-04-2018/12:57:00TRIPPED DUE TO B-N
LINE FAULTKPTCL/ TANTRASNCO
TANTRANSCO:
No visible fault
KPTCL:
4 220KV-AMBEWADI-XELDEM 21-04-2018/14:15:00 21-04-2018/17:43:00B PHASE TO GROUND
FAULTKPTCL/ GED
KPTCL:
5 220KV-YERRAANDAHALLI-HOSUR_TN-1 24-04-2018/13:10:00 24-04-2018/13:25:00tripped at hosur end
onlyKPTCL/ TANTRANSCO
TANTRANSCO:
No visible fault
KPTCL:
Radially fed from Hosur
6 400KV-HINDUJA-KV_KOTA-1 01-05-2018/10:12:00 01-05-2018/11:24:00 TRIPPED ON B-N FAULT HNPCL/ APTRANSCO
APTRANSCO:
Patrolling was done.No visible fault found.
Tree cutting done.
HNPCL:
7 400KV-JINDAL-BPS-2 03-05-2018/19:56:00 03-05-2018/21:53:00 BREAKER AIR LOCK OUT JSWEL/ KPCL
JSWEL:
KPCL:
8 400KV-NARNOOR-JAMMALAMADUGU-1 03-05-2018/17:29:00LINE TO GROUND
FAULTAPTRANSCO
APTRANSCO:
Feeder tripped at both ends. At that time
Heavy rain ,wind and thunders were
reported.
9 400KV-RTPS-BTPS-1 04-05-2018/14:14:00 04-05-2018/19:26:00 TRIPPED ON B-N FAULT KPCLKPCL:
10 400KV-RTPS-BTPS-1 05-05-2018/12:54:00 05-05-2018/17:57:00TRIPPED DUE TO B-N
LINE FAULTKPCL
KPCL:
Pending Remedial Measures/ Actions taken
for the Critical Tripping Incidents (as on 12.07.2018)
Annexure-III
Page 1 of 8
11 220KV-YERRAANDAHALLI-HOSUR_TN-1 10-05-2018/11:50:00 10-05-2018/12:18:00 C-N fault KPTCL/ TANTRANSCOTANTRANSCO:
Passing fault
12 220KV-UDUMALPET_TN-IDDUKKI-1 11-05-2018/15:44:00 11-05-2018/16:58:00 TRIPPED ON R-N FAULT TANTRANSCO/ KSEBL
TANTRANSCO:
Passing fault
KSEBL:
Tripped on Ph to Ph fault in Z1, Carrier send,
A/R Lock out
13 400KV-UPCL-HASSAN-1 11-05-2018/20:41:00 Tripped on Y-B Fault UPCL/ PGCIL (SR-II)KPTCL:
Stood OK after test charging.
14 400KV-NARENDRA-GUTTUR-1 14-05-2018/23:39:00H /T TO CONTAIN OVER
VOLTAGRKPTCL
KPTCL:
15 400KV-NEYVELI_TS_II-SALEM-1 14-05-2018/12:37:00 14-05-2018/17:28:00LINE TO GROUND
FAULTNLCIL/ PGCIL (SR-II)
NLCIL :
The feeder got tripped on line to ground
fault . The feeder got auto reclosed at
Neyveli TS2 end but it again got tripped on
sustained fault. The feeder was charged
from Salem end but it got tripped again .
Requested to PGCIL for patrolling of the
line.
PGCIL (SR-II):
16 400KV-PAVAGADA-TUMKUR-3 14-05-2018/23:43:00H /T TO CONTAIN OVER
VOLTAGRPGCIL (SR-II)
PGCIL (SR-II):
17 400KV-NEYVELI_TS_II-SALEM-1 15-05-2018/11:16:00 15-05-2018/20:59:00TRIPPED ON Y PHASE
FAULTNLCIL/ PGCIL (SR-II)
NLCIL :
The feeder got tripped on line to ground
fault . The feeder got auto reclosed at
Neyveli TS2 end but it again got tripped on
sustained fault. The feeder was charged
from Salem end but it got tripped again .
Requested to PGCIL for patrolling of the
line.
PGCIL (SR-II):
18 400KV-KUDGI_PG-KHOLAPUR_PG-1 17-05-2018/16:27:00 17-05-2018/16:59:00 TRIPPED ON R-N FAULT PGCIL (SR-II)PGCIL (SR-II):
19 400KV-RTPS-BTPS-1 21-05-2018/21:15:00 21-05-2018/22:17:00 DISTANCE PROTECTION KPCL/ KPTCL
KPCL:
KPTCL:
20 400KV-BTPS-HIRIYUR-2 21-05-2018/20:48:00 R-Y FAULT KPCL/ PGCIL (SR-II)
KPCL:
PGCIL (SR-II):
Annexure-III
Page 2 of 8
21 400KV-TUMKUR-KUDGI_PG-2 23-05-2018/18:52:00 23-05-2018/20:03:00 TRIPPED ON R-N FAULT PGCIL (SR-II)PGCIL (SR-II):
22 400KV-MYSORE-KOZHIKODE-2 23-05-2018/15:07:00 23-05-2018/15:16:00 TRIPPED ON B-N FAULT PGCIL (SR-II)PGCIL (SR-II):
23 400KV-BTPS-HIRIYUR-2 24-05-2018/10:36:00 24-05-2018/15:29:00 Triiped on R-B Fault KPCL/ PGCIL (SR-II)
KPCL:
PGCIL (SR-II):
24 400KV-TUMKUR-KUDGI_PG-2 24-05-2018/22:24:00 TRIPPED ON Y-N FAULT PGCIL (SR-II)PGCIL (SR-II):
25 400KV/230KV UDUMALPET-ICT-1 27-05-2018/16:10:00 27-05-2018/17:18:00 MAL-OPERATION PGCIL (SR-II)
PGCIL (SR-II):
26 400KV-NAGAPATTNAM_PS-NEYVELI_TS_II 28-05-2018/13:17:00 28-05-2018/13:48:00TRIPPED ON SINGLE
PHASE TO GND FAULTPGCIL (SR-II)/ NLCIL
NLCIL :
The feeder got tripped on Zone 2 distance
protection due to a fault in NPS- ILFS feeder.
PGCIL (SR-II):
27 400KV-MEPL-NPS-1 29-05-2018/12:33:00 R-Y FAULT MEPL/ PGCIL (SR-I)
PGCIL(SR1): Line tripped on R-Y fault. At
NPS: Main-I: Dist. 22.53km, FC: 13.11kA,
Main-II: Dist: 22.80km, FC: 13.10kA.
Fault jurisdiction comes into MEPL section.
MEPL:
28 230KV-PUDUCHERRY-VILLIANUR-1 30-05-2018/08:40:00R-pH CT BLAST at
VILIANURPED
PED:
29 400KV-GUTTUR-HIRIYUR-2 01-06-2018/15:38:00B phase light arrester
flashoverKPTCL/ PGCIL (SR-II)
To-be-discussed
30 400KV/220KV GUTTUR-ICT-1 01-06-2018/19:01:00 01-06-2018/19:34:00 RELAY MALOPERATION KPTCLTo-be-discussed
Annexure-III
Page 3 of 8
31 400KV-KTPS_VII-KHAMMAM-1 01-06-2018/21:25:00BUS BAR PROTECTION
OPERATEDTSGENCO/ PGCIL (SR-I)
PGCIL(SR1):
Khammam-KTPS-1 line tripped on R-N fault
in 1st attempt & Y-B persisting fault. It is
reported that CT blasted at KTPS end.
TSGENCO:
At 21:25 hrs R ph CT blasted in TIE-1(b/w
KTPS-VI to KTPS-VII line and KTPS-VI to
KHAMMAM PGCL line). At that time Line
Khammam-KTPS-1 line tripped on R-N fault
in 1st attempt & Y-B persisting fault.
32 400KV-MAMIDAPALLI-KHAMMAM-1 01-06-2018/17:57:00 01-06-2018/18:10:00 RELAY MALOPERATION TSTRANSCO/ PGCIL (SR-I)
PGCIL (SR-I):
Khammam-Mamidipally-1 line tripped at
KMM end only. At Mpally end A/R sucessful
but Khammam end A/R not attempted due
to operation of DEF protection at KMM.
From DR & EL it is clearly observed that fault
is directional & persisted long time which
caused the operation of DEF protection.
Relay operation is in order.
TSTRANSCO:
A/R operated and successful at Suryapet
end.
33 400KV-GUTTUR-HIRIYUR-1 01-06-2018/13:10:00 DT RECEIVED KPTCL/ PGCIL (SR-II)To-be-discussed
34 400KV-SURYAPET-KV_KOTA-1 01-06-2018/19:17:00 01-06-2018/19:44:00 TRIPPED ON R-N FAULT TSTRANSCO
TSTRANSCO:
A/R operated and successful at Suryapet
end.
35 400KV/220KV BTPS-ICT-1 01-06-2018/00:01:00 01-06-2018/01:10:00R-pH OVER CURRENT
RELAY OPERATEDKPCL
To-be-discussed
36 400KV-KTPS_VI-KTPS_VII-1 01-06-2018/21:25:00BUS BAR PROTECTION
OPERATEDTSGENCO
TSGENCO:
At 21:25 hrs R ph CT blasted in TIE-1(b/w
KTPS-VI to KTPS-VII line and KTPS-VI to
KHAMMAM PGCL line). At that time Line
tripped on R-ph differential trip at both
ends.
Annexure-III
Page 4 of 8
37 400KV-NELLORE_PG-THIRUVALAM-1 02-06-2018/19:24:00 02-06-2018/19:35:00 TRIPPED ON Y-N FAULT PGCIL (SR-I)/ PGCIL (SR-II)
PGCIL (SR1):
Line tripped on Y-N fault. A/R attempted
sucessfully and line tripped on persisitng Y-
N fault. From NLR distance: M1:138.3 kms,
FC: 3.5kA & M2: distance 139.3kms,
FC:3.1kA. From TVLM end distance M1
distance 46.5 kms, FC: 7.5kA & M2 distance
46.2 kms, FC: 7.45 kA.
Fault distance comes under SR-2 TLM
Jurisdiction.
PGCIL (SR-II):
38 400KV-YELHANKA-NELAMANGALA-1 02-06-2018/19:53:00 02-06-2018/20:00:00 TRIPPED ON R-N FAULT PGCIL (SR-II)/ KPTCLTo-be-discussed
39 400KV-JINDAL-BPS-1 03-06-2018/16:04:00 03-06-2018/19:05:00 DISTANCE PROTECTION JSWEL/ KPTCLTo-be-discussed
40 400KV-BPS-YTPS-1 03-06-2018/16:03:00 03-06-2018/18:52:00 DISTANCE PROTECTION KPTCL/ KPCLTo-be-discussed
41 400KV-SALEM-UDUMALPET-1 08-06-2018/08:48:00 08-06-2018/09:10:00
TRIPPED DUE TO R -
PHASE WINDING OF ICT
4 BURNOUT AT
SALEM(TN)
PGCIL (SR-II)
To-be-discussed
42 220KV-AMBEWADI-PONDA-1 10-06-2018/09:29:00 10-06-2018/09:50:00 TRIPPED ON B-N FAULT KPTCLTo-be-discussed
43 400KV-HINDUJA-KV_KOTA-2 10-06-2018/12:01:00 TRIPPED ON Y-N FAULT HNPCL/ APTRANSCO
APTRANSCO:
A/R successful at K.kota end but again
tripped on DT Receive pulse from HNPCL
end.
HNPCL:
44 400KV/220KV GOOTY-ICT-2 14-06-2018/17:04:00 14-06-2018/21:17:00 RELAY MALOPERATION PGCIL (SR-I)To-be-discussed
45 400KV-BHOOPALAPALLY-WARANGAL-2 14-06-2018/11:31:00 14-06-2018/17:36:00 PLCC MAL OPERATION TSGENCO/ PGCIL (SR-I)To-be-discussed
46 230KV-PUDUCHERRY-VILLIANUR-1 15-06-2018/07:29:00 15-06-2018/09:12:00
Burst of B phase CT HV
side of Auto
Transformer - I
PUDUCHERRY ED/ PGCIL
(SR-II)
To-be-discussed
47 400KV-HOODY-NELAMANGALA-1 15-06-2018/12:12:00 15-06-2018/13:03:00 PLCC MAL OPERATION KPTCLTo-be-discussed
48 400KV-BIDADI-TUMKUR-2 15-06-2018/16:20:00 15-06-2018/17:03:00R Phase distance
protection operatedPGCIL (SR-II)
To-be-discussed
49 400KV-VIJAYAWADA-NELLORE_AP-2 15-06-2018/18:08:00 15-06-2018/18:20:00TRIPPED ON B PHASE
FAULTPGCIL (SR-I)/ APTRANSCO
APTRANSO:
Line belongs to PGCIL.
Annexure-III
Page 5 of 8
50 765KV-KURNOOL_PG-THIRUVALAM-2 15-06-2018/22:10:00 15-06-2018/23:51:00 TRIPPED ON Y-N FAULT PGCIL (SR-I)/PGCIL (SR-II)To-be-discussed
51 230KV-NEYVELI_TS_II-VILLIANUR-1 15-06-2018/07:29:00 15-06-2018/08:45:00
Burst of B phase CT HV
side of Auto
Transformer - I
NLCIL/ PUDUCHERRY ED
To-be-discussed
52 400KV/220KV HOODY-ICT-3 17-06-2018/03:53:00CT FLASH OVER at 220
kV SIDEKPTCL
To-be-discussed
53 400KV/220KV HOODY-ICT-1 17-06-2018/03:53:00TRIPPED ON OCR
OPERATEDKPTCL
To-be-discussed
54 400KV/220KV RAICHUR_KA-ICT-2 17-06-2018/03:54:00
OVER FLUX
PROTECTION RELAY
OPERATED
KPCL
To-be-discussed
55 HVDC 500KV KOLAR_DC Pole 1 18-06-2018/17:42:00 18-06-2018/18:02:00esof received from
talcherPGCIL (SR-II)
To-be-discussed
56 HVDC 500KV KOLAR_DC Pole 2 18-06-2018/17:42:00 18-06-2018/18:03:00esof received from
talcherPGCIL (SR-II)
To-be-discussed
57 HVDC500KV-TALCHER-KOLAR_DC-2 18-06-2018/17:42:00 18-06-2018/18:03:00esof received from
talcherPGCIL (SR-II)
To-be-discussed
58 HVDC500KV-TALCHER-KOLAR_DC-1 18-06-2018/17:42:00 18-06-2018/18:02:00esof received from
talcherPGCIL (SR-II)
To-be-discussed
59 220KV-SEDAM-TANDUR-1 19-06-2018/01:44:00 19-06-2018/03:10:00
BUSBAR PROTECTION
OPERATED AT SADEM
END
KPTCL/ TSTRANSCO
TSTRANSCO:
The fault was high resistance fault and Earth
fault protection operated at Tandur end.
60 400KV-NARNOOR-SRISAILAM_LEFT_BANK-1 20-06-2018/18:51:00DT RECEIVED AT
SRISAILAMAPTRANSCO/ TSGENCO
APTRNSCO:
Feeder not tripped at Narnoor end.
61 400KV-URAVAKONDA-MEHBOOBNAGAR-1 20-06-2018/08:07:00 20-06-2018/08:26:00 DT RECEIVED APTRANSCO/ TSTRANSCO
APTRANSCO: Feeder tripped on over
voltage at Uravakonda end.
TSTRANSCO:
Tripped on Direct Trip received indications
at Veltoor end.
62 400KV-NARNOOR-SRISAILAM_LEFT_BANK-1 21-06-2018/23:56:00 DISTANCE PROTECTION APTRANSCO/ TSGENCOTo-be-discussed
63 400KV-BHOOPALAPALLY-WARANGAL-1 21-06-2018/21:51:00 21-06-2018/22:26:00 TRIPPED ON Y-N FAULT TSGENCO/ PGCIL (SR-I)To-be-discussed
64 400KV-KUDANKULAM-TIRUNELVELI-1 21-06-2018/17:37:00 21-06-2018/18:11:00 CT FAILEDNPCIL (KKNPP)/ PGCIL (SR-
II)
To-be-discussed
65 400KV-MADURAI-TIRUNELVELI-1 21-06-2018/17:37:00 21-06-2018/18:55:00 CT FAILED PGCIL (SR-II) To-be-discussed
66 400KV-HINDUJA-KV_KOTA-2 22-06-2018/22:18:00 22-06-2018/22:40:00 TRIPPED ON R-N FAULT HNPCL/ APTRANSCOTo-be-discussed
67 400KV-GUTTUR-JINDAL-1 22-06-2018/06:05:00 TRIPPED ON R-N FAULT KPTCL/ JSWELTo-be-discussed
68 400KV/220KV DINDI-ICT-1 22-06-2018/06:29:00 22-06-2018/18:33:00 RELAY MALOPERATION TSTRANSCOTo-be-discussed
Annexure-III
Page 6 of 8
69 400KV-BHADRAVATHI-RAMAGUNDAM-1 25-06-2018/20:34:00 25-06-2018/21:08:00DT RECEIVED FROM
BHADRAVATHIPGCIL (SR-I)/ NTPC
To-be-discussed
70 400KV/110KV PALAVADI-ICT-3 25-06-2018/17:14:00ICT-3 B-Ph CT blast at
PalvadiTANTRANSCO
To-be-discussed
71 400KV-PALAVADI-TIRUVALAM_TN-1 25-06-2018/17:14:00ICT-3 B-Ph CT blast at
PalvadiTANTRANSCO
To-be-discussed
72 400KV-BHADRAVATHI-RAMAGUNDAM-2 25-06-2018/19:20:00 25-06-2018/21:12:00To take line reactor into
servicePGCIL (SR-I)/ NTPC
To-be-discussed
73 400KV/220KV BTPS-ICT-1 26-06-2018/04:17:00 Evacuation of Feeders KPCLTo-be-discussed
74 400KV-BPS-YTPS-2 27-06-2018/17:24:00 27-06-2018/18:41:00 TRIPPED ON R-N FAULT KPTCL/ KPCLTo-be-discussed
75 220KV-AMBEWADI-PONDA-2 28-06-2018/00:56:00 DISTANCE PROTECTION KPTCL/ GEDTo-be-discussed
76 400KV-HASSAN-MYSORE-1 28-06-2018/01:44:00H /T TO CONTAIN OVER
VOLTAGRPGCIL (SR-II)
To-be-discussed
77 400KV-KUDGI_PG-NARENDRA-2 28-06-2018/02:12:00H /T TO CONTAIN OVER
VOLTAGRPGCIL (SR-II)/ KPTCL
To-be-discussed
78 400KV/110KV SALEM_TN-ICT-3 29-06-2018/20:07:00TRIPPED ON BUCCHOLZ
RELAY OPERATIONTANTRANSCO
To-be-discussed
79 400KV-RASIPALYAM-ANAIKADAVU-2 29-06-2018/07:30:00 R-Y FAULT TANTRANSCO To-be-discussed
80 220KV-AMBEWADI-PONDA-1 01-07-2018/10:57:00 01-07-2018/12:01:00 DISTANCE PROTECTION KPTCL/ GEDTo-be-discussed
81 400KV/110KV SUNGAVARACHATRAM-ICT-3 02-07-2018/19:53:00 02-07-2018/23:15:00Tripped on LV side Y-Ph
LA blastTANTRANSCO
To-be-discussed
82 400KV-KTPS_VI-KHAMMAM-1 02-07-2018/13:38:00 02-07-2018/17:31:00 TRIPPED ON B-N FAULT TSGENCO/ PGCIL (SR-I)To-be-discussed
83 400KV-CEPL-TUTICORIN_PS-2 02-07-2018/16:38:00 02-07-2018/17:28:00 TRIPPED ON R-N FAULT CEPL/ PGCIL (SR-II)To-be-discussed
84 400KV/230KV KAMUDHI-ICT-1 03-07-2018/13:40:00 03-07-2018/20:25:00TRIPPED ON BUCCHOLZ
RELAY OPERATIONTANTRANSCO
To-be-discussed
85 400KV-GHANAPUR-RAMAGUNDAM-3 06-07-2018/14:40:00 07-07-2018/03:04:00 TRIPPED ON Y-N FAULT PGCIL (SR-I)/ NTPCTo-be-discussed
86 400KV-BPS-YTPS-1 06-07-2018/19:12:00 TRIPPED ON LA BLAST KPTCL/ KPCLTo-be-discussed
87 220KV-UDUMALPET_TN-IDDUKKI-1 08-07-2018/16:01:00 TRIPPED ON B-N FAULT TANTRANSCO/ KSEBTo-be-discussed
88 400KV-JINDAL-BPS-4 08-07-2018/20:10:00 08-07-2018/20:56:00DT RECEIVED AT JINDAL
ENDJSWL/ KPTCL
To-be-discussed
89 400KV-KARAIKUDI-KAYATHAR-2 08-07-2018/09:48:00 08-07-2018/10:10:00DT RECEIVED AT
KARIKUDI ENDPGCIL (SR-II)/ TANTRANSCO
To-be-discussed
90 400KV-PAVAGADA-TUMKUR-3 08-07-2018/20:10:00TRIPPED ON Y PHASE
FAULTPGCIL (SR-II)
To-be-discussed
91 400KV-CUDDAPAH-CHITTOOR-1 10-07-2018/17:15:00 10-07-2018/17:25:00 DT RECEIVED PGCIL (SR-I)/ APTRANSCOTo-be-discussed
Annexure-III
Page 7 of 8
92 400KV-HINDUJA-KV_KOTA-1 10-07-2018/11:29:00 TRIPPED ON R-N FAULT HNPCL/ APTRANSCOTo-be-discussed
93 400KV-HINDUJA-KV_KOTA-2 10-07-2018/11:29:00 DT RECEIVED HNPCL/ APTRANSCO To-be-discussed
94 400KV/230KV SHOLINGANALLUR-ICT-1 11-07-2018/19:04:00OLTC Surge Relay
operatedTANTRANSCO
To-be-discussed
95 220KV-AMBEWADI-PONDA-1 11-07-2018/06:15:00 11-07-2018/17:14:00LINE TO GROUND
FAULTKPTCL
To-be-discussed
Annexure-III
Page 8 of 8
Compliance Status of the Recommendations given in the Special Meeting on HVDC Gajuwaka Pole Trippings held on 02.04.2018
Sl. No. Recommendation given Status of Implementation Remarks
1 POWERGRID to see the feasibility of providing suitable Circuit Breaker on the tertiary (33 kV) side of ICT-2, and implement the same, if feasible.
Status furnished vide PGCIL (SR-I) mail dated 23.05.2018: 33kV CBs are available for both Tertiaries of ICT-1 & 2 in downstreams at Pole-1 & Pole-2.
Pending
2 It was agreed to keep LT side (415 V bus connected) CB’s and fuses under observation to ascertain whether they operate with required time discrimination.
Status furnished vide PGCIL (SR-I) mail dated 23.05.2018: Fuse discrimination available in 415V LT side
Complied
3 POWERGRID to look into the correctness of the settings employed on the 220 kV side of ICT-1 and revise them if necessary and provide a copy the settings employed to SRPC Secretariat.
Status furnished vide PGCIL (SR-I) mail dated 23.05.2018: The settings are as per POWERGRID standard settings. The copy of settings shared with SRPC.
Pending
4 Arrangement for ensuring full-fledged redundancy for Pole-1 (ICT-1 tertiary + ICT-2 tertiary + its DG), replacement of LT side Circuit Breakers and commissioning of PLC based AMF panel forPole-1 would be completed well before 28.04.2019.
Status furnished vide PGCIL (SR-I) mail dated 23.05.2018: All LT CB's pertaining to Pole -1 have been replaced on shutdown on dated 28.04.2018 and 29.04.2018. The new PLC has also been installed and commissioned.
Complied
5 (i) Verification of various logics in effecting AC supply auto-changeover from ICT-1 tertiary to ICT-2 tertiary to DG set for Pole-1 would be tested and completed by availing shut down on 28th & 29th April, 2018. During this period, mock-exercise would also be conducted for verification of proper functioning / sequence of operation of new PLC. POWERGRID would give the procedure & detailed schedule of testing in the OCC meeting of April, 2018.
Status furnished vide PGCIL (SR-I) mail dated 23.05.2018: The same has been checked during installation and commissioning of PLC on shutdown on dated 28.04.2018 and 29.04.2018.
Complied
6 As a short-term measure for avoiding pole trippings under ferro-resonance conditions, immediate disconnection of FSC would be effected by ensuring fool-proof communication of the ferro-resonance carrier signal from Gajuwaka to Jeypore. To achieve this, it was agreed that the existing PLCC based carrier communication would be replaced by fibre-
Status furnished vide PGCIL (SR-I) mail dated 23.05.2018: The station level checks of the code transmission path was carried out at both Vizag and Jeypore ends. The FSC detection code transmission was successful in both instances of detection of
Pending
Annexure-IV
Page 1 of 2
optic communication by installing Digital Tele-Protection Couplers (DTPCs) at both ends within 2 months (i.e., by May, 2018). It was also agreed that dual communication channels would be provided to ensure reliable bypassing of FSCs.
ferro-resonance on 04.04.2018 and 17.04.2018 and there was no Pole 2 tripping. The New DTPC's are expected to receive by June 2018. The same shall be commissioned by availing shgutdown of 400kV Jeypore-Gajuwaka - 1 & 2 lines (one by one) in Jul/Aug'2018.
7 As a medium-term measure for avoiding pole trippings under ferro-resonance conditions, it was agreed that POWERGRID would expedite commissioning of the proposed STATCOM at Jeypore end to improve general voltage profile under disturbance/ fault conditions.
Status furnished vide PGCIL (SR-I) mail dated 23.05.2018: Under progress in Odisha Projects
Pending
8 It was also agreed to study the effect of the proposed STATCOM on improving the voltage profile under transient conditions, to establish its efficacy in arresting ferro-resonance kind of phenomena, and based on the study results to devise a scheme to effect auto-bypassing of FSC for low power order (say 400 MW) in Jeypore – Gajuwaka lines.
Status furnished vide PGCIL (SR-I) mail dated 23.05.2018: Shall be done after commissioning of STATCOM at Jeypore end
Pending
9 As a long-term measure for avoiding pole trippings under ferro-resonance conditions, it was agreed that POWERGRID would carry out necessary refurbishment works of controller protections at Jeypore end for detecting ferro-resonance locally at FSC location (Jeypore end) and effect automatic by-passing of FSCs by putting necessary infrastructure in place at Jeypore end. POWERGRID was requested to furnish a concrete proposal with suitable time-lines in this regard.
Status furnished vide PGCIL (SR-I) mail dated 23.05.2018: To be decided/approved in SRPC / Standing committee meetings
Pending
Annexure-IV
Page 2 of 2
Auto-Reclosure Implementation on all 220 kV & above transmission lines of Southern
Region
The status of implementation of A/R (excluding Tie-lines & Radial feeders & Cables) as
furnished by SR-Constituents is as follows:
Sl.
No. Name of the Constituent
220 kV
400 kV 765 kV
Total no. of lines
No. of lines where A/R is in service
Total no. of lines
No. of lines where A/R is in service
Total no. of lines
No. of lines where A/R is in service
1 APGENCO (Hydro)
19
(Tie-lines: 8)
Nil --- --- --- ---
2 APGENCO (Thermal)
25 Nil 6 6 --- ---
3 APTRANSCO 215 63 54 54 --- ---
4 TSGENCO (Hydro)
15 Nil 5 Nil --- ---
For the 5 no. of 400 kV lines, A/R has been kept disabled since they are of composite type (consist of Cable of length 1 km).
5 TSGENCO (Thermal)
15
(Tie lines:4)
Nil 6 6 --- ---
6 TSTRANSCO 241 10 50 50 --- ---
7 KPCL 44
(Tie-lines: 8)
8 11
(Tie-lines: 4)
7 --- ---
8 KPTCL 241 9 29 29 --- ---
9 TANGEDCO & TANTRANSCO
215
139 32 32 --- ---
10 KSEB 61 56 --- --- --- ---
11 PED 6 6 --- --- --- ---
12 PGCIL (SR-I) --- --- 68 68 14 14
13 PGCIL (SR-II) 15 15 92 92 2 2
14 NTPC
NTPC-Simhadri --- --- 8 8 --- ---
NTPC-Kudgi --- --- 4 4 --- ---
NTPC-
Ramagundam
4 Nil 10 10 --- ---
On 220 kV lines, A/R has not been provided as they are of very short length (1 km).
NTPC-
Kayamkulam
6 6 --- --- --- ---
15 NPCIL
MAPS 4 Nil --- --- --- ---
Annexure-V
Page 1 of 10
KGS 2 Nil 4 4 --- ---
A/R on 220 kV lines has not been provided since they are between two generating stations
KKNPP 2 Nil 4 4 --- ---
16 BHAVINI 4 Nil --- --- --- ---
17 NLCIL 10
(Tie-lines: 3)
2 9
(Tie-lines: 2)
7 --- ---
18 JSWEL 2 Nil 2 2 --- ---
19 UPCL 2 Nil 2 2 --- ---
20 NTECL-Vallur --- --- 6
(Tie-lines: 2)
4 --- ---
21 TPCIL --- --- 2 2 --- ---
22 CEPL --- --- 2 2 --- ---
23 HNPCL --- --- 2 2 --- ---
24 IL&FS --- --- 2 2 --- ---
25 Lanco KPL 2 Nil 2 2 --- ---
For the 220 kV lines, since the distance between Kondapally and VTPS Stage IV is only one
span (350 mtrs), A/R has been kept blocked from both the ends.
26 NTPL --- --- 2 2 --- ---
27 MEPL --- --- 2 (Tie-line: 1)
1 --- ---
28 SEL --- --- 2 2 --- ---
Annexure-V
Page 2 of 10
Action plan furnished by SR-Constituents for implementing A/R on the 220 kV & above
transmission lines, where it is presently not in service:
Sl. No.
Constituent Action plan for implementing A/R
1 APGENCO (Hydro)
At 220 kV level, there are total 19 feeders, out of which 8 lines are tie-lines. Action plan for the remaining 11 lines is as given below:
Sl. No.
Name of the Station
Name of the Feeder Action plan for implementing of Auto-reclosure
1
Srisailam Right Bank Power House
SSLM- Dindi- I
Auto-reclosure scheme for all 220kV is available but not commissioned since inception
A/R scheme will be implemented while commissioning of new protection panels, whose inspection is complete and about to dispatch. Protection Couplers are commissionedfor all the feeders except Dindi – I & II and Nagarjunasagar feeders. Expected to be completed by March, 2018.
2 SSLM- Dindi-II
3 SSLM-Tallapalli-l
4 SSLM- Tallapalli-II
5 SSLM- Podili
6 SSLM- Markapuram
7 SSLM- Mydukur
8 SSLM- BilakalaGuduru
9 SSLM-Somayajulapalli
10 SSLM-Nagarjunasagar
Between Generating Stations (Optional)
Not willing to provide being feeder between two generating stations
11
Lower Sileru Power House (LS)
L - Bommuru
Auto-reclosure scheme is available but not commissioned since inception
A/R scheme will be implemented while commissioning of new protection panels for which tender evaluation is in progress. Protection Coupler was commissioned and work is expected to be completed by August 2018.
12 LS-Donkarayi Between Generating Stations (Optional)
Not willing to provide being feeders between two generating stations
13 LS-Kothagudem- I
14 I.S-Kothagude rn-Il
15
Upper Sileru Power House (US)
US - Pendurthy Auto-reclosure scheme is available but not commissioned since inception
A/R scheme will be implemented while commissioning of new protection panels for which tender evaluation is in progress. Protection Coupler was commissioned and work is expected to be completed by August 2018.
16 US-Donkarayi Between Generating Stations (Optional)
Not willing to provide being feeders between two generating stations 17 US-Balimela
18 Donakari Canal Power House DCPH
DCPH-Upper Sileru Between Generating Stations (Optional)
Not willing to provide being feeders between two generating stations
19 DCPH- Lower Sileru
Annexure-V
Page 3 of 10
2 APGENCO (Thermal)
W.r.t. existing 400 kV lines, A/R is in service on all 6 lines.
At 220 kV level, there are two plants under APGENCO (Thermal) viz. Dr. NTTPS (VTPS) and Rayalaseema TPP (RyTPP). The action plan furnished for implementing A/R is as follows:
VTPS: A/R scheme is available for 9 feeders out of the total 15 feeders, but not commissioned since inception. For remaining 6 feeders, Static relays have to be replaced with Numerical relays to facilitate Auto-Reclose. An action plan for replacement of existing static relays of the feeders with numerical relays under PSDF funds was initiated. The time-line proposed for implementing on all 15 feeders is as follows:
Sl. No.
Name of 220 kV feeder
Whether A/R Enabled
Action plan
1. VTS-PODILI No Implemented by 16.03.2018
2. VTS-Gunadala No Implemented by 16.03.2018
3. VTS-Nunna No Implemented by 16.03.2018
4. VTS-K'Kota No Implemented by 16.03.2018
5. VTS-Tadikonda·1 No Implemented by 16.03.2018
6. VTS-Tadikonda·2 No Implemented by 16.03.2018
7. VTS-Tallapalli No Implemented by 16.03.2018
8. VTS-Tallapalli-3 No Implemented by 16.03.2018
9. VTS-Tallapalli·4 No Implemented by 16.03.2018
10. VTS-Narasa Rao Pet No Implemented by 16.09.2018
11. VTS-Chillakallu- l No Implementation of A/R for these feeders deferred, since they are of composite type (consist of Cable of length 1.5 km above the ground) implemented by 16.09.2018
12. VTS-Chillakallu-2 No
13. VTS-Konadapalli -l No
14. VTS-Konadapalli -2 No
15. VTS-Renatachintala No Implemented by 16.09.2018
As per above schedule, the implementation of A/R scheme will be completed at NTTPS by 16.09.2018.
RyTPP: Action plan for implementing A/R scheme includes procurement of necessary auxiliary relays, scheme checking/modification, testing and commissioning for the following 10 no. of 220 kV Transmission lines:
Sl. No. Name of 220kV Feeder Date of Completion of A/R scheme
1 RTPP – Chinakampalli -1 17.09.2018
2 RTPP – Chinakampalli -2 18.09.2018
3 RTPP – Chinakampalli -3 19.09.2018
4 RTPP – Chinakampalli -4 20.09.2018
5 RTPP – Yerraguntla -1 22.09.2018
6 RTPP – Yerraguntla -2 24.09.2018
7 RTPP – Pulivendula -1 25.09.2018
8 RTPP – Pulivendula -2 27.09.2018
9 RTPP – Thimmapuram -1 29.09.2018
10 RTPP – Thimmapuram -2 30.09.2018
As per above schedule, the implementation of A/R scheme will be completed at RyTPP by 30.09.2018.
Annexure-V
Page 4 of 10
3 APTRANSCO A/R scheme is implemented in all 400 kV network, and will be implemented for the latest & upcoming future 220 kV & above lines in APTRANSCO.
W.r.t. existing 400 kV lines, A/R has been proposed for 54 lines out of the total 59 lines, and is in service on all 54 lines.
W.r.t. existing 220 kV lines, A/R has been proposed for 215 lines out of the total 258 lines. Of these 215 lines, A/R is in service on 63 lines. For the remaining 186 lines, action plan for implementing A/R is as follows:
Category of feeders
No. of 220 kV Feeders
Time-line for A/R Implementation
Remarks
Feeders on which A/R is proposed to be implemented in Phase-I
19 3 months from July, 2017
Completed
Feeders on which A/R is proposed to be implemented in Phase-II
23 6 months from July, 2017
A/R implemented on 11 lines
Feeders on which A/R is proposed to be implemented in Phase-III
40 12 months from July, 2017
---
Feeders on which A/R is proposed to be implemented in Phase-IV
104 15 months from July, 2017
---
4 TSGENCO (Hydro) At 400 kV level, there are total 5 no. of lines. However, A/R has been kept disabled on them since they are of composite type (consist of Cables of length 1 km).
The action plan for the existing 15 no. of 220 kV lines is as follows:
Sl. No.
Name of the Plant
Total no. of 220 kV lines
Action Plan
NSHES (220 kV) 5 Will be implemented by 30.04.2018
PJHEP (220 kV) 4 Will be implemented by 31.05.2018
LJHEP (220 kV) 4 Will be implemented by 31.05.2018
PCHES (220 kV) 2 Will be implemented by 30.06.2018
5 TSGENCO (Thermal) Out of the existing 15 no. of 220 kV lines, 4 are tie-lines. Action plan for the remaining 11 lines is given below:
Annexure-V
Page 5 of 10
Sl. No.
Name of the Plant
No. of Feeders
Action plan for implementing A/R
1 KPTS/ O&M 6 (i) Miryalaguda (ii) Shapurnagar (iii)Lower Sileru-I (iv)Nunna (v) Manuguru-I (vi) Manuguru-II
A/R feature for all 220 kV feeders will be completed by June, 2018as the material procurement is under progress
2 KTPS/ Stage-V 3 (i) Budidampadu-I (ii) Budidampadu-II (iii) Lower Sileru-II
For these feeders, A/R scheme is configured and ready to be enabled. Once the other end substations complete the implementation process, A/R can be put into service. Presently, negotiations are on with the OEM's of Relays suppliers for testing of the scheme.
3 KTPS/ Stage-V 2 Sitaramapuram – I & II As per SRPC recommendation, it is decided to implement Line Differential Protection Scheme on these Lines (having Line length less than 10 kms). For this, the existing distance Relays would be replaced with Differential Relays. Presently, procurement of LDP relays is in progress. A/R would be implemented in the new LDP relays. In the existing distance Relays, A/R has been configured, and ready to be enabled. However, the same would be put into service after implementation of the same from the remote end station.
4 KTPS/ O&M 2 Tie Lines I & II As these lines are connecting between generating stations, it is decided to not implement A/R scheme on these lines as per reference minutes of the 62nd meeting of PCSC held on 15.03.2017.
5 KPTS/ Stage-V 2 Tie Lines I & II
6 TSTRANSCO For all the upcoming 220 kV & above feeders, the concerned wings have been requested to ensure A/R function and its implementation in the field.
W.r.t. existing 400 kV lines, A/R has been proposed for 50 lines out of the total 52 lines, and is in service on all 50 lines.
W.r.t. existing 220 kV lines, A/R has been proposed for 241 lines out of the total 269 lines. Of these 241 lines, A/R is in service on 10 lines. For the remaining 231 lines, action plan for implementing A/R is as follows:
Annexure-V
Page 6 of 10
Category of feeders
No. of 220 kV
Feeders Time-line for A/R Implementation
Feeders on which A/R is proposed to be implemented in Phase-I (immediately)
171 31.08.2018
Feeders on which A/R is proposed to be implemented in Phase-II (with minor modifications)
32 31.12.2018
Feeders on which A/R is proposed to be implemented in Phase-III (with major modifications)
28 30.06.2019
5 KPCL Out of the total 44 no. of 220 kV lines, there are 8 no. of tie-lines. Out of the remaining 36 lines, A/R is in service on 8 no. of lines. Action plan for implementing A/R on the remaining 28 no. of lines is as follows:
On 9 no. of lines emanating from RTPS, A/R function is Ready at RTPS end. M/s. KPTCL informed that A/R function will be enabled only after R&M works of Numerical Protection system and R&M works are under progress.
On 9 no. of lines emanating from Sharavathy GS, A/R function will be kept 'ON' only after completion of Earth Mat augmentation works, which will be completed by March – 2018.
On 2 no. of lines emanating from Gerusoppa PH, 220kV Line Breakers are having problems. Proposed for replacement under PSDF. After replacement of Breakers Auto reclosure feature will be enabled - Time required 24-30 Months approximately.
On 2 no. feeders emanating from Kadra, settings for Auto reclosure feature completed at Kadra. Clearance from M/s. KPTCL is awaited.
On 6 no. of feeders emanating from Nagjheri, Auto-reclose scheme is ready at NPH end and will be enabled in all the six lines (Nagjhari - Hubli-1, Nagjhari - Hubli-2, Nagjhari - Hubli-3, Nagjhari -Bidnal, Nagjhari - Ambewadi-1, Nagjhari -Ambewadi-2) once clearance from respective receiving end is obtained.
6 KPTCL W.r.t. existing 400 kV lines, A/R is in service on all 29 lines.
W.r.t. existing 220 kV lines, A/R has been proposed on 241 lines out of the total 279 lines. Of these 241 lines, A/R is in service on 9 lines. Action plan for the remaining lines is given below: AR scheme tested and it is ready to be enabled at Sharavathy &
STRP lines (10 in no.) at 220kV Substations Shimoga,Talaguppa, Shiralakoppa and BTPS. It is communicated to KPCL to confirm regarding readiness at their end.
Retrofitting of Main-2 distance scheme in place of back up OC and EF relays of 220kV lines is being carried out under R&U project awarded to M/s GE T&D India Limited. Works at 26 No.s of audited sub stations are taken up on priority and M-II retrofitting work is completed at many sub stations. Along with M-II retrofitting works, AR Scheme testing is also completed at one end of the line for about 25 no.s of 220kV lines. Other end belongs to KPCL/Power Grid/ KPTCL where M-II retrofitting is yet to be taken up. Readiness from our end is already communicated to KPCL
Annexure-V
Page 7 of 10
regarding 220kV lines emanating from Talaguppa, Shimoga and Shiralakopa and Lingapur connecting to Sharavathy, STRP, and BTPS Genarating Stations. Confirmation awaited from their end. Also, AR scheme is ready for enabing for 220 kV PGCIL connected lines at Kadakola, Tubinkere and Gowribidanur Sub Stations. Communication will be sent to Power Grid shortly.
Providing auto reclosure for 220kV lines connected to Generating stations, POWERGRID stations and ISTS is planned to be completed by end of March 2018. Remaining lines will be taken up along with commissioning of M-II scheme and will be completed before end of December 2018.
7 TANGEDCO &
TANTRANSCO
W.r.t. existing 400 kV lines, A/R is in service on all the existing 32 no. of feeders.
W.r.t. existing 230 kV lines, A/R has been proposed for 215 lines out of the total 239 lines. Of these 215 lines, A/R is in service on 139 lines. Action plan for the remaining 76 lines is given below:
Category of feeders
No. of Feeders
Time-line for A/R Implementation
Generation connected feeders (excluding tie-lines)
66 CVT supplied. AR will be enabled by June-2018
Communication network to be provided
8 Communication network established for 6 feeders. Control cable to be provided for AR implementation. Timeline requested: March-2018.
Breaker problem 1 Procurement of Breaker is under progress by availing PSDF. AR will be enabled by June-2018.
Inter-State feeder 1 AR to be provided at Chittoor end in 230kV Thiruvalam-Chittoor feeder
8
KSEB Details of 220 kV feeders where A/R was not implemented are as follows:
Sl. No.
Feeder Name Status of A/R facility
Remarks
1 220 kV Kozhikode-PG – Areacode line-1 Short lines; Current Differential Protection provided; so A/R not provided. 2 220 kV Kozhikode-PG – Areacode line-2
3 220 kV Kozhikode-PG – Areacode line-3
4 220 kV Shornur – Areakode NIL Optical fibre link work is Completed, SDH equipment work is awarded, Protection coupler is under tendering process. Expected to be commissioned during June, 2018.
5 220 kV New Pallom – Pallom line Very short line; Pilot wire protection implemented; auto-reclosing facility not provided.
Annexure-V
Page 8 of 10
10 NPCIL (Kudankulam NPP)
A/R has not been kept in service on the TTPS bound 230 kV line as TTPS is a generating station.
A/R on SR Pudur bound 230 kV line is proposed to be put in service by April, 2018.
11 NPCIL (MAPS) A/R on all four 230 kV lines would be put into service by September, 2018. P.O. was placed on M/s Crompton Greaves limited for CVTs on 22.12.2017. The expected delivery period is six months i.e. on or before 20-06-2018. Implementation would take about another three months. Thus, A/R implementation would be completed by 30.09.2018.
12
NLCIL There are total 10 no. of 220 kV lines. Out of these, 3 are tie-lines, and A/R is in service on 2 no. of lines (Villianur & Bahour). For the remaining 5 lines, action plan for implementing is as follows: For the 3 no. of lines emanating from NLC TS-I, the issue of
implementing A/R was discussed in PCSC-71 meeting held on 31.01.2018. The time-line for implementing A/R has been fixed as June, 2018.
For the 2 no. of lines emanating from NLC TS-II (Kadalangudi, Ulundurpet), the issue of implementing A/R was discussed in PCSC-71 meeting held on 31.01.2018. The time-line for implementing A/R has been fixed as June, 2018.
13 UPCL The A/R in 220 kV lines at UPCL end has already been configured and scheme is ready.
On completion of A/R readiness at opposite end (Kemar) the A/R can be put in service.
14 JSWEL A/R logic being uploaded in both the line relays. Trial would be taken after getting confirmation from 220 kV Lingasugur (KPTCL) end. Planned to be completed by 15.02.2018.
In this regard, the time-line committed by various SR-Constituents for implementing A/R on their 220 kV & above transmission lines is given below:
Sl. No.
Name of the Constituent
Time-frame for implementing A/R on 220 kV lines
Time-frame for implementing A/R on 400 kV
lines
Time-frame for
implementing A/R on 765
kV lines
1 APGENCO (Hydro) August, 2018 N/A ---
2 APGENCO (Thermal) September, 2018 Implemented ---
3 APTRANSCO October, 2017 – October, 2018 Implemented ---
4 TSGENCO (Hydro) June, 2018 N/A ---
5 TSGENCO (Thermal) June, 2018 Implemented ---
6 TSTRANSCO August, 2018 – June, 2019 Implemented ---
7 KPCL March, 2018 – June, 2020 Implemented ---
Annexure-V
Page 9 of 10
8 KPTCL March, 2018 – December, 2018 Implemented ---
9 TANGEDCO & TANTRANSCO
June, 2018 Implemented ---
10 KSEB June, 2018 N/A ---
11 PED Implemented N/A ---
12 PGCIL (SR-I) N/A Implemented Implemented
13 PGCIL (SR-II) Implemented Implemented Implemented
14 NTPC
NTPC-Simhadri N/A Implemented ---
NTPC-Kudgi N/A Implemented ---
NTPC-Ramagundam N/A Implemented ---
NTPC-Kayamkulam Implemented N/A ---
15 NPCIL
MAPS September, 2018 N/A ---
KGS N/A Implemented ---
KKNPP April, 2018 Implemented ---
16 BHAVINI Not furnished N/A ---
17 NLCIL June, 2018 Implemented ---
18 JSWEL February, 2018 Implemented ---
19 UPCL Not furnished Implemented ---
20 NTECL-Vallur N/A Implemented ---
21 TPCIL N/A Implemented ---
22 CEPL N/A Implemented ---
23 HNPCL N/A Implemented ---
24 IL&FS N/A Implemented ---
25 Lanco KPL N/A Implemented ---
26 NTPL N/A Implemented ---
27 MEPL N/A Implemented ---
28 SEL N/A Implemented ---
*****
Annexure-V
Page 10 of 10
Sl. No. Bay name/Bus Voltage Protection/Element/
Equipment/ System
auditated
Remarks/Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
1 Control and
Protection Panels
For 400 KV Busbar protection, one number of main Bus bar protection
scheme is available for each bus; Check Zone protection is available as
inbuilt feature to main relay (Distributed system).Commissioning of new
busbar protection panels with nemerical relay is under progress.
Mail dated 14.02.2018:
New Busbar protection panels with numerical relay
commissioned on 17.12.2016.
Complied
2 On 220 kV side, Only Single Bus bar protection scheme is available (ABB
RADSS) for each of the two buses . No redundant main 2 or Check zone
protection available. CT supervision relays are not provided. Redundant
Bus bar protection or Check zone shall be considerd.
Mail dated 14.02.2018:
New 220KV Busbar protection panel will be commissioned by
May 2018.
Pending
3 Auto-reclose feature is not enabled for 220kV lines. Mail dated 14.02.2018:
Completed. Auto-reclosure feature enabled for all 220KV lines.
Complied
4 Over current protection has been kept enabled on alll 400 kV feeders. Mail dated 14.02.2018:
Normal Over current function is not enabled in MICOM P444
relay. Over current function with SOTF is enabled. During dead
line charging condition it acts as SOTF function and remaining
time it acts as definite time over current function. However
considerable time delay 3 seconds and 200% pick up is adopted.
Pending
5 For all 220 kV feeders [except S.Palli-1 Main-2 feeder (ABBREL670)] all
relays are of static relays.
Mail dated 14.02.2018:
All the static relays were replaced with numerical relays during
retrofitting works. Completed for all 220KV feeders.
Complied
6 400kV Ghanapur line Main -1 is of POTT (SEL 421) scheme and Main-2 is
of PUTT scheme.
Mail dated 14.02.2018:
Main-1 SEL 421 relay which was with POTT was replaced with
7SA522 with PUTT during retrofitting works. 400KV Ghanapur
(now Maheswaram) line Main-1 and Main-2 kept in PUTT
scheme.
Complied
7 Relay Setting Pole discrepency relay time :
- 2.5s for 400kV Power grid transmission line main and tie breakers.
- 1.25s for 400kV AP TRANSCO (Srisailam) transmission line main and
1.5s for tie breakers.
- 0.5s for 220kV transmission lines.
- 0.5s for ICT-1 and Bus Reactor.
- 2.5s for ICT-2.
Mail dated 14.02.2018:
Pole discrepancy relay time provided as per standard. (Line main
breaker:1.5s, Tie breaker:2.5s, Transformer and Reactor
breakers:0.5s) And for all 220KV transmission lines 1.5s
provided.
Complied
Status of Implementation of New Protection Audit Recommendations (as on 12.06.2018)
APTRANSCO
1) 400/ 220 kV Narnoor SS [16–18 February, 2016]
1/70
Annexure-VI
Page 1 of 70
8 PSB was kept blocked for all zones with unblock time delay of 2 sec on
400 kV Srisailam feeder. For all 400 kV PGCIL feeders, PSB was kept
blocked for all zones except zone-1 with unblock time delay of 2 sec.
Mail dated 14.02.2018:
APTRANSCO views on power swing protection philosophy
communicated to SRPC vide
Lr.No.CPS/SP/121/SRPC/D.No.510/15, Dt.14.12.2015. As per
setting provided.
Pending
9 400kV Stub protection current set and time delay set as I> 150% and
100ms against the recommendeed setting of I>250% and time delay of
50ms by M/S Tractebel. APTRANSCO to take action as appropriate.
Mail dated 14.02.2018:
As per APTRANSCO practise Stub protection pick up current
setting 200% and time delay 0 ms is adopted.
Pending
10 Zone resistive reach setting & time setting for all 400kV and 220kV
distance protection are found to be different from the recommanded
setting given by Tractebel based on Ramakrishna committee
recommendations (Task force committee guidelines). APTRANSCO to
take action as appropriate.
Mail dated 14.02.2018:
The existing resistive reach settings are found to be OK for
distance protection resistive reaches.
Complied
11 DEF is enabled in main-1 and disabled in main-2 distance relay in 400kV
srisailam line . Due to this, DEF will not be available in the event of
outage of Main-1 distance relay. DEFR timing on 400 kV feeders was
found to be kept at different settings (308 msec, 470 msec.)
Mail dated 14.02.2018:
DEF is enabled in Main-1 and Main-2 distance relay in 400KV
Srisailam line. (New relays for Main-2 provided with 7SA522.)
Complied
12 SOTF funtion disabled in all 220 kV feeders except Somayajulapalli line-1
(main-2) and Brahmanakotkur line (Main-1 & 2).
Mail dated 14.02.2018:
SOTF function enabled for all 220KV feeders.
Complied
13 The distance protection for all 200 kV feeders was configured for three
(forward) zones only. There was no reverse-zone available for the
distance protection provided on 220 kV feeders. In 220kV B. Kotkur
feeder, distance protection was configured with 5 zones (forward - zone -
1 to 4); however, zone-5 was kept off.
Mail dated 14.02.2018:
The distance protection for all 220KV feeders configured for four
(forward) and one (reverse) zone.
Complied
14 Over current and directional earth fault protections are not provided on
any of the 220kV lines.
Mail dated 14.02.2018:
In old realys these functions are not available.Over current and
directional earth fault protections provided for all 220KV lines
during retrofitting works (Numerical relays).
Complied
15 High set unit was not provided for over flux protection of ICT’s. Mail dated 14.02.2018:
Inverse charactaristic is selected for over flux protection.
Complied
16 GPS is not available. Mail dated 14.02.2018:
GPS provided.
Complied
17 Stand alone DR with automatic downlaoding facility to centralized PC is
not availble. Stand-alone EL though available, is not in working condition.
APTRANSCO informed that manual downloading from relay specific DR's
and EL's is being done as and when fault occurred for 400kV lines.
Mail dated 14.02.2018:
Centralised EWS is provided for downloading EL and DR
automatically.
Complied
18 DR is not available for 400kV/220kV bus bar protection and for all 220kV
lines .
Mail dated 14.02.2018:
1. Completed for 400KV Busbar protection DR can be download.
2. Completed for 220KV lines DR can be downloaded.
3. Pending for 220KV Busbar protection panel; will be
commissioned by May 2018.
Pending
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Annexure-VI
Page 2 of 70
19 AC Distribution Auto Changeover is not available in ACDB for 415V Auxiliary supply 1 & 2
and DG set. Auto Main FAilure (AMF) panel in DG set is not in service.
Supply Change over operation is carried out manually.
Mail dated 14.02.2018:
Auto changeover operation is not possible in ACDB for 415V
Auxilary supply 1&2 and DG set as with the existing older
version of LT AC scheme, where the necessary protection
scheme for changeover operation is not available and hence the
supply change over operation is being carried out manually.
Pending
20 For ACDB, there is only one AC source from 33kV/11kV Narnoor SS;
however, the same is being fed to various switchyard auxiliaries through
two parallel transformers.
Mail dated 14.02.2018:
It was requested the APSPDCL authorities for the alternate 11KV
supply source and the same will be completed by May 2018.
Pending
21 DC Distribution For 220kV and 400kV bus bar protection panel, 2 DC sources are
available with selector switch only. Automatic changeover is not provided.
Mail dated 14.02.2018:
Completed:-For 400KV busbar protection panel (new panel
commissioned), 2 DC sources are available and automatic
changeover provided. Pending:-
220KV Busbar protection panels will be commissioned by May
2018.
Pending
22 Communication
system
In Communication panels (except Ghanapur, Gooty and AP Carbides 1 &
2 feeders as per shceme), each panel has been supplied with dual DC
source.
Mail dated 14.02.2018:
There is no provision of dual DC source for PLCC equipments.
Complied
23 The communication with the only numerical relay (ABB REL670) available
on S.Palli line-1 (Main-2) feeder, was found to be unhealthy.
Mail dated 14.02.2018:
The communication with the only numerical relay (ABB REL670)
available on S.Palli line-1 (Main-2) feeder is rectified and found
healthy. Main-1 also provided with numerical relay.
Complied
24 Walkie-talkie system for communicating with Control room personnel is
not provided.
Mail dated 14.02.2018:
Walkie takie will be provided by May 2018.
Pending
25 400kV/
220kV
Switchyard Field
Equipments
Even though the designed 220 kV busbar arrangement has bus-1 & bus-2
& transfer bus, the transfer bus was kept out of service, and the transfer
bus coupler is being used as line-CB. With this arrangement, breaker
maintenance cannot be undertaken without availing line shutdown
Mail dated 14.02.2018:
The rectification/modification works will be attended in the due
course duly entrusting the works either in the existing contacts (
if any) or in forth coming tenders/orders.
Pending
26 Lightning protection (LA's) Earthing is not done as per standards/ NFPA
in the most of 220kV and 400kV bays. LA's (system) earthing is
connected to earth electrodes directly as well as through equipment
earthing.
Mail dated 14.02.2018:
Attended & Rectified as per the directions given by the
protection audit team by isolating the surge counters from the
erected structures of 220KV and 400KV lightening arrestors with
insulating media.
Complied
27 400kV Bus reactor has not been equipped with cooling fans. Mail dated 14.02.2018:
Attended & Rectified by arranging cooling fans to 63MVAR
400KV Bus reactor.
Complied
28 Door earthing not done for some of marshalling boxes iin 400kV and
220kV bays; PVC conduits for cable entries to the marshalling boxes
found to be kept unsealed in some of the 400kV and 220kV bays.
Mail dated 14.02.2018:
Attended & Rectified by arranging door earthing to all the
marshalling boxes in the 400KV and 220KV bays as well as seal
the PVC conduits to the marshalling boxes.
Complied
3/70
Annexure-VI
Page 3 of 70
29 220 V Battery Units and Battery chargers were housed in the same room
along with other relay panels. 48 V Battery Units and Battery chargers
were housed in the same room along with other PLCC panels
Mail dated 14.02.2018:
The 220V Battery units and Battery chargers were housed in the
same room along with other relay panels and 48V Battery units
and Battery chargers were housed in the same room along with
other PLCC panels at the time of commissioning of the Sub-
station by the Construction wing as per the approved plan &
design.
Pending
30 General It is observed that the existing test-kits are of obsolete models and not in
working condition. The following test kits shall be generally required for
proper maintenance of 400 kV Narnoor SS:
1. Digital Earth resistance Tester
2. 12 kV Capacitance and Tan Delta Kit
3. Digital Multi Meter Model:287
4. Digital Low Range Tong Tester
5. Energey Meter Testing Kit
6. Dynamic Contact Resistance Measurement Test Kit
7. Transformer Winding Resistance Measurement Test Kit
8. Transformer Turns Ratio Kit
9. Insulation Resistance test-kit with induction compensator
Mail dated 14.02.2018:
Items Nos 2 & 7 are provided. The remaining kits will be
arranged by July 2018.
Pending
31 It is observed that no Laptop with latest features for downloading the
disturbance data and relay settings is available.
Mail dated 14.02.2018:
Received laptop during retrofitting works.
Complied
Sl. No. Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
1 Yet to be informed
2 Yet to be informed
3 Yet to be informed
4 Yet to be informed
5 Yet to be informed
6 Yet to be informed
7 Yet to be informed
2) 400/ 220 kV Uravakonda SS [5–6 April, 2018]
Deficiences/Nonconformity observed
Substation is well maintained.
The following have been found to be satisfactory:
(i) Operation of various electrical & mechanical interlocks
(ii) Remote operation of Isolators from work-station
(iii) Earth-mat resistance is around mandated limits (Measured value - 0.51 ohms)
Protection Philosophy being followed by APTRANSCO for various transmission elements (Lines/ ICT's/ Reactors/ Busbar/ etc.) shall
be furnished.
In 400 kV lines, distance protection timings for Zone-2, Zone-3, Zone-4 and Zone-5 (reverse) shall be reviewed in line with
Ramakrishna Committee guidelines.
The existing Power Swing Philosophy (with all Zones blocked for unblocked time delay) for 220 kV & 400 kV transmission lines to
be reviewed to adopt either of the following two approaches:
(i) Zone-1 --> Trip; Highers Zones --> Block for a delay of unblocking time delay (2 sec) & then Trip.
(ii) Block all Zones with Out-of-Step tripping enabled at electrical zero locations by carrying out required system studies.
In view of the short length of the 220 Amidyala lines 1 & 2 (9. 45 km), Line Differential Protection may be provided in place of the
existing distance protection.
Auto-Reclosure feature provided on 400 kV & 220 kV lines may be got checked for correctness of functionality & healthiness of the
logic employed.
4/70
Annexure-VI
Page 4 of 70
8 Yet to be informed
9 Yet to be informed
10 Yet to be informed
11 Yet to be informed
12 Yet to be informed
13 Yet to be informed
14 Yet to be informed
15 Yet to be informed
16 Yet to be informed
17 Yet to be informed
18 Yet to be informed
19 Yet to be informed
20 Yet to be informed
21 Yet to be informed
22 Yet to be informed
23 Yet to be informedAC Supply Changeover Scheme for the Substation may be provided
Door-to-Panel earthing may be provided in various control & marshalling boxes
Visual display indicating bay-element names may be suitably provided for all 400 kV & 220 kV bays.
Cable trenches in the switchyard should be covered properly. Control Cables & Power Cables may be properly segregated in
different trays provided in the cable trenches.
It is observed that Substation is not having Internet connectivity. Steps may be taken to provide the same to enable substation
personnel to discharge their official duties effectively.
It is observed that some of the relays not communicating with SAS Work Station, which may be rectified.
Walkie-talkie system for yard communication is not available, which may be provided.
It is observed that earth-resistance for various identified Points of station earth-mat have been measured in 2016. It is
recommedned to measure these earth resistances on yearly basis, and maintain relevant records with suitable earth lay-out
diagrams.
It is obsereved that metal spreading has not been provided in HV & LV side bays of ICT-3 and ICT-4. Since these bays have
already been kept in operation, it is recommended to take up this job on priority basis so as to ensure safety for the working
personnel by maintaining touch & step potentials within limits.
Smoke detection systems have been found to be either not installed or not in working condition in 220 kV kiosks. It is recommeded
to rectify the same, and put them into operation at the earliest.
It is observed that Pole Discrepancy time delay has not been set uniformly. It is recommended to keep PDR gtime delays as
follows:
(i) For all line Main-CB's and Tie-CB's where Aut-Reclosure with priority has been employed with dead-times of 1 sec & 2 se
respectively, PDR time delay shall be kept as 1.5 sec and 2.5 sec respectively.
(ii) For all other elements, PDR time delay shall be kept as the minimum avaiable in the relay, but not less than 100 msec. This
may be preferably kept as 0.5 sec.
For the 400/ 220 kV ICT's, O/C & E/F protections high-set operation may be provided with time delay of 50 msec.
O/C Protection (high-set & IDMT) may be provided on 220 kV sides of the 400/ 220 kV ICT's.
Group-A Protections and Group-B Protections for 400/ 220 kV ICT's shall be arranged to be fed from different DC Supplies.
Re-Trip feature time delay for the circuit breakers shall be revised from the existing 200 msec to 100 msec.
Automatic supply changeover from AC auxiliary supply to DG set may be provided. Also remote starting of DG set may be provided
from control room SCADA
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Page 5 of 70
Sl. No. Bay name/Bus Voltage Protection/Element/
Equipment/ System
auditated
Remarks/Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
1 Control and
Protection Panels
Main 1 & Main 2 distance relay are of same make, Type & model in
Miryalaguda and Shapoornagar feeders .
Mail dated 30.01.2018:
Main –I & Main-II different make/model of Miryalaguda and
Shapoornagar feeders relays were procured and it will be
replaced whenever LC is available by deputing the service
engineer
Pending
2 DC supervision relays are not availble for all feeders. Mail dated 30.01.2018
DC supervision relays for all the feeders were commissioned.
Complied
3 For 220 KV Busbar protection,one number of main distributed Bus bar
protection scheme and inbuilt Check Zone protection is available. CT
supervision relays are not seperately provided.
Mail dated 30.01.2018
220 KV Bus bar Protection Scheme through differential current
Alarm CT supervision was provided.
Complied
4 220 kV Tie line-2 main-1 relays is of static relays (ABB RADSL). Mail dated 30.01.2018
220 kV Tie line-2 main- I relays were replaced with new RED-
670 relays
Complied
5 For 220kV Main 1& Main 2 distance protection same CT core is used. Mail dated 30.01.2018
Due to Phasing out of the Units in 2019, it will not be possible to
procure the new CTs with two protection cores.
Pending
6 Remote indication of WTI and OTI of IBT-3&4 not provided in control
room.
Mail dated 30.01.2018
As per the existing OT&WT gauges it is not possible to provide
the remote indication at control room
Pending
7 Smoke detection system is not available in control room building. Mail dated 30.01.2018
Due to Phasing out of the Units in 2019 it will not possible to
implement smoke detection system
Pending
8 Relay Setting Auto-reclose feature is not enabled for 220kV lines. Mail dated 30.01.2018
Auto-reclose feature for all 220kV lines will be enabled soon.
Pending
9 Zone time setting & Resistive reach setting for distance protection are
found to be different from the recommanded setting given by Tractebel
based on Ramakrishna committee recommendations (Task force
committee guidelines).
Mail dated 30.01.2018
All the feeder settings were followed by as per the CE/
PowerSystems/TSTransco Recommendations only.
Pending
10 PSB was kept blocked for all zones. Mail dated 30.01.2018
Followed as per the CE/PowerSystems /TSTransco
Recommendations
Pending
11 All distance protection zones are set as forward Direction and Reverse
zone is not provided in distance relay (Main-1 & Main-2) for
Nunna,Manuguru-1&2,Tie line-1&2 feeders.
Mail dated 30.01.2018
followed as per the CE/PowerSystems /TSTransco
Recommendations
Pending
TSGENCO
1 (i) 220 kV KTPS (O&M) [14-16 March, 2016]
6/70
Annexure-VI
Page 6 of 70
12 For 220kV Tie line-1&2, STUB function is in activated condition in Main-2
distance relay (REL-100)
Mail dated 30.01.2018
Tie line 1&2 REL-100 relays were replaced with RED-670 &
MICOM P442 relays.
Pending
13 Carrier aided protection is available only in Nunna feeder and is not
provided for any of the 220kV feeder due to non-availability of PLCC/
Wave trap.
Mail dated 30.01.2018
Carrier aided protection for all Feeders panels were
commissioned and relay mapping will be done by deputing
service Engineer.
Pending
14 AC Distribution Auto Changeover is not available in ACDB for 415V Auxiliary supply 1 & 2. Mail dated 30.01.2018
As per the existing scheme AC change over was not available
Pending
15 DG set is not available to cater to substation loads.TSGENCO informed
that procurement of DG is under progress.
Mail dated 30.01.2018
From the existing DG set one source was connected to
emergency loads of 220 KV switch Yard.
Pending
16 DC Distribution One source of 110V DC supply only available for substation loads and one
DC source only used for Trip coil 1 & 2.,
Mail dated 30.01.2018
As per the existing scheme only one 110 V DC source was
available.
Pending
17 Earth leakage is observed in KTPS(O&M)-A station.The measured values
at battery is as below:
P-N:114.6V ; P-E:110V ;N-E:1.3V;
Mail dated 30.01.2018
Earth leakage of KTPS –‘A’ station was identified in 220KV Bus
coupler Bay and it was isolated.
Complied
18 Acid leakageand bulging of batteries is observed in KTPS(O&M)-C station
220V batteries.
Mail dated 30.01.2018
Failed batteries in KTPS(O&M)-C station were replaced with new
batteries.
Complied
19 Communication
system
Common PC with auto downloading facility for relays DRs is not available. Mail dated 30.01.2018
As per the existing scheme it was not provided.
Pending
20 GPS is not available. Mail dated 30.01.2018
GPS was commissioned and it was time synchronized with the
numerical relays.
Complied
21 Stand alone EL is not availble. Mail dated 30.01.2018
EL was not available in the existing scheme.
Pending
22 DR is not available for 220kV Tie line ckt-1 & 2. Mail dated 30.01.2018
220 KV Tie-1&2 old RADSL relays were replaced with new RED-
670 & Micom P442 relays and now they are provided with DR.
Complied
23 Redundancy not maintained in Fibre optic termination equipment. Mail dated 30.01.2018
Fiber optic termination equipment redundancy was provided.
Complied
24 PLCC protection couplers are not availbale for 220kV lines except Nunna
feeder.
Mail dated 30.01.2018
For all 220KV feeders PLCC protection Couplers were provided.
Complied
25 220kV Switchyard Field
Equipments
Wave trap is available only in Nunna feeder. Mail dated 30.01.2018
Wave traps are available for all the feeders except Miryalaguda
feeder.
Pending
7/70
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Page 7 of 70
26 Lightning Arrestor Earthing is not done as per standards/ NFPA in the
most of 220kV bays. LA's (system) earthing is connected to earth
electrodes directly as well as through equipment earthing. Healthiness
checking (leakage current measurement) of Lightrning Arrestor is not
being done.
Mail dated 30.01.2018
As per the standards LA Earthing is provided directly.
Complied
27 In most of the 220kV bays, LA surge counters and monitors (Nunna,IBT3
& 4,Tie line,Miryalaguda) are not in working condition.
Mail dated 30.01.2018
LA surge counters and monitors were replaced with new ones.
Complied
28 In 220kV Nunna line Y phase CVT is not available. Mail dated 30.01.2018
220 KV Nunna line Y-Phase CVT will be replaced
soon.
Pending
29 In 220kV Bus Coupler-II Y phase CT is not available. Mail dated 30.01.2018
220 KV Bus Coupler-II Y-Phase CT will be replaced soon.
Pending
30 Walkie-talkie system for yard communication is not avalable. Mail dated 30.01.2018
Walkie-talkie system for yard communication was provided.
Complied
31 Lot of Grasses and other weeds are found over the Gravels in the 220kV
KTPS-A & C yard.
Mail dated 30.01.2018
Grasses and other weeds were removed over the grounds in 220
KV KTPS-A & C yards.
Complied
32 Air pressure low alarm checking was done for Buscoupler bay breaker. CB
trouble/ air pressure low alarm did not get activated in controlroom.
Mail dated 30.01.2018
CB trouble/Air pressure low alarm card was replaced with new
one and it is found OK.
Complied
33 It is observed that line CVT structures corroded in Miryalayaguda bay.
Action may be taken to rectify the same.
Mail dated 30.01.2018
Line CVT corroded structures were cleaned and painted.
Complied
34 For few 220kV bays, it is observed that the Marshalling box and indication
window of circuit breakers are not visible.
Mail dated 30.01.2018
Marshalling Box and Indication window of circuit breakers were
provided.
Complied
35 Bay identification codes/name and phase identification are not visible. Mail dated 30.01.2018
Bay identification codes/names and phase identification were
provided
Complied
36 Oil leakage was observed in 220kV IBT 3 & 4 bushing turrets and oil inlet
pipes.
Mail dated 30.01.2018
Oil leakage was arrested for IBT-3&4 and also IBT-3 transformer
was replaced with 100MVA transformer from TSTRANSCO.
Complied
Sl. No. Bay name/Bus Voltage Protection/Element/
Equipment/ System
auditated
Remarks/Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
1 (ii) 220 kV KTPS (Stage-V) [14-16 March, 2016]
8/70
Annexure-VI
Page 8 of 70
1 Control and
Protection Panels
On 220 kV side, Only Single Bus bar protection scheme is available (High
impedance Static type - ABB RADSS) for each of the two buses . No
redundant main 2 or Check zone protection available. CT supervision
provided as inbuilt feature. No DR is available.
Mail dated 30.01.2018
Planning to replace total 220kv bus bar protection panels in the
upcoming R&M at KTPS-V 220 KV switchyard.
Pending
2 Relay Setting Auto-reclose feature is not enabled for 220kV lines. Mail dated 30.01.2018
Tie Lines-I&II: As these lines are connecting between
generating sub stations, we are not implementing Auto
Reclosure scheme on these lines as per reference minutes of the
62nd meeting of PCSC held on 15.03.2017.
Budidampadu-I&II and Lower Sileru-II: For these lines the
Auto Reclosure scheme is configured and ready to enable in our
substation. Once the other end substations complete the
implementation process we can enable the scheme on our side.
We are also in ther process of negotiation with the OEM's of
Relays for testing of the scheme.
Sitarampatnam-I&II: As per SRPC recommendation it is
decided to implement Line Differential Protection Scheme on
these Lines (having Line length less than 10 KMs). For this we
need to replace the existing distance Relays with Differential
Relays. We are in the process of procuring the Differentioal
Relays. We will implement the A/R scheme in the new
Differential relays. In the existing distance Relays we are
configured A/R feature and to enable in our substation once
other end S/S complete the implementation process.
Pending
3 PSB was kept blocked for all zones. Mail dated 30.01.2018
It is enabled for all zones in our latest Numerical Relays of
220KV feeders in KTPS-V switchyard.
Pending
4 Zone time setting & Resistive reach setting for distance protection are
found to be different from the recommended setting given by Tractebel
based on Ramakrishna committee recommendations
Mail dated 30.01.2018
The settings provided by TSTRANSCO were configured in all our
latest Numerical Relays of 220kv feeders in KTPS-V switchyard.
Pending
5 The distance protection for all 200 kV feeders (except for REL670) was
configured with 3 zones (forward) zones only. There was no reverse-zone
available for the distance protection provided on 220 kV feeders.
Mail dated 30.01.2018
Four forward and one reverse Zones were configured in our
latest Numerical relays of 220KV feeders in KTPS-V switchyard ,
which are provided by TSTRANSCO.
Complied
6 For Budidampadu line-1 and Lower sileru line-2 , STUB function is in
activated condition in Main-1 distance relay (REL-100) and binary output
is not configured.
Mail dated 30.01.2018:
In KTPS-V 220KV swichyard , Budidampadu line-1 and lower
sileru line-2 STUB function is in deactivated condition in Main-1
distance relay which are replaced with REL-670 Numerical
relays.
Complied
7 Carrier aided protection is available only in Budidampadu feeder-2 and is
not provided for any of the 220kV feeder due to non-availabilyi of PLCC/
Wave trap.
Mail dated 30.01.2018:
New PLCC panels for all 7 No.220KV feeders at KTPS-V stage
swichyard were installed, But commissioning is under progress
and it is in scope of TSTRANSCO.
Pending
8 DEF protection not available in Budidampadu-1 feeder. Mail dated 30.01.2018:
It is configured in latest Numerical relays of all 7 No.220KV
feeders at KTPS-V stage swichyard.
Complied
9/70
Annexure-VI
Page 9 of 70
9 Main-2 distance relay (Make ABB, Type - REZOA) is of static type in 220
kV Sitaramapatnam-1&2, Budidampadu-1&2 and Lower sileru-2 feeders.
Relay does not have DR feature, cannot be time synchronized with GPS
and there is no provision for additional features in these relays
Mail dated 30.01.2018:
In 220KV feeders of KTPS-V SWITCHYARD, Main-2 distance
relay (Make ALSTOM make MICOM P442) is in service for
Sitaramapatnam-1&2, Budidampadu-1&2 and Lower sileru-2
feeders which has DR feature and can be time synchronised
with GPS and there is provisions for additional features in these
relays.
Complied
10 AC Distribution DG set not available to cater substation loads.TSGENCO informed that
entension of supply from generating station DG will be planned shortly.
Mail dated 30.01.2018:
Indent for DG set is raised at KTPS-V 220KV swichyardand it is
in procurement stage.
Pending
11 DC Distribution One source of 48V DC system is available.TSGENCO informer that
commisioning of second source of 48V DC system is under progress.
Mail dated 30.01.2018:
In KTPS-V 220KV stage swichyard Second 48V battery bank also
available with same charger. Second charger procurement is
under process.
Pending
12 Communication
system
Common PC with auto downloading facility for relays DRs is not available. Mail dated 30.01.2018:
For all KTPS-V stage swichyard, Separate Laptop is maintaining
for Relay configuration,retreiving DRs and Els
Pending
13 GPS is not available. Mail dated 30.01.2018:
For KTPS-V 220KV swichyard, Indent is raised and it is in
procurement stage.
Pending
14 Stand alone EL is not availble. Mail dated 30.01.2018:
For all 220KV feeders of KTPS-V swichyard, Stand alone EL is
available with latest Numerical Relays.
Complied
15 The communication with the only numerical relay (ABB REL670/RED670)
is available. Interfacing cables for relay setting and DR extraction is not
availble for REL 511 relays.
Mail dated 30.01.2018:
In KTPS-V Switchyard, 220KV Feeder REL511 Relays were
retrofitted with ALSTOM make MiCOM P442 Numerical Relays.
Complied
16 Redundancy not maintained in Fibre optic termination equipment. Mail dated 30.01.2018:
In KTPS-V Switchyard, new PLCC equipment installed for all
220KV Feeders which are having redundancy in fibre optic
termination equipment.
Complied
17 PLCC protection couplers are not availbale for 220kV lines except
Budhidampadu feeders.
Mail dated 30.01.2018:
In KTPS-V Switchyard, new PLCC equipment installed for all
220KV feeders it is under commissioning stage and it is in scope
of TSTRANSCO.
Pending
18 220kV Switchyard Field
Equipments
Wave trap available in Sitaramapatnam-1&2 (inter circuit coupling and in
Budidampadu feeder-2. Wave trap is not available in other 220kV
feeders.
Mail dated 30.01.2018:
In KTPS-V 220 KV Switchyard, Wave traps are available for
BDPD-I & II, SRPM-II, LSR-II feeders(SRPM-II has 2 wave
traps), only SRPM-I feeder doesn't have wave-trap.
Pending
19 Even though the designed 220 kV busbar arrangement has bus-1 & bus-2
& transfer bus, the transfer bus was kept out of service due to the low
SF6 pressure in transfer bus circuit breaker.
Mail dated 30.01.2018:
In KTPS-V 220KV Switchyard, the Transfer Bus is in healthy
conditions (all its interlocks also checked). Now breaker is filled
with required SF6 gas pressure.
Complied
10/70
Annexure-VI
Page 10 of 70
20 Lightning Arrestor Earthing is not done as per standards/ NFPA in the
most of 220kV bays. LA's (system) earthing is connected to earth
electrodes directly as well as through equipment earthing. Healthiness
checking (leakage current measurement) of Lightrning Arrestor is not
being done.
Mail dated 30.01.2018:
In KTPS-V 220KV Switchyard, earthing for LA's were provided as
per the standards and leakage current monitoring is recording
every quarterly.
Complied
21 In most of the 220kV bays, LA surge counters and monitors are not in
working condition.
Mail dated 30.01.2018:
In KTPS-V 220KV Switchyard, Indent is raised for LA's surge
counters and monitors and it is in procurement stage.
Pending
22 Walkie-talkie system for communicating with Control room personnel is
not provided.
Mail dated 30.01.2018:
In KTPS-V 220KV Switchyard, Walkie-Talkie system will be
procured shortly, presently dedicated Mobile phones are
available location-wise (MCR, UCB)
Pending
Sl. No. Bay name/Bus Voltage Protection/Element/
Equipment/ System
auditated
Remarks/Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
1 Relay Setting Stub protection current set and time delay set as I> 150% and 100ms. Mail dated 30.01.2018:
stub protection current set value and time delay value are
I>150% and 0 ms
Pending
2 Main-1 relays all five zones are looking forward direction.No reverse zone
provided.
In Main-2 relays four zones are kept in forward direction and Zone-5 is of
reverse direction.
Mail dated 30.01.2018:
Reverse Zone protection for main-I provided
Complied
3 AC Distribution DG set is not available to feed substation loads.TSGENCO informed that
extension of supply from generating station DG will be planned shortly.
Mail dated 30.01.2018:
Supply extended from Generating Station DG
Complied
4 DC Distribution 2nos, 220 V DC system each with one Battery chargers , one no of
Battery bank and one DCDB with Bus couplers are available. Each set
will feed Trip circuit 1 and Trip circuit 2 separately. In the event of failure
of one set , Buscoupler will be closed manually to extend supply to the
affected section.
Mail dated 30.01.2018:
Presently existing system with buscoupler will be closed
manually to the affected section.
Complied
5 Communication
system
Common PC with auto downloading facility for relays DRs is not available.
TSGENCO informed that dedicated PC is available but not in working
condition at present.
Mail dated 30.01.2018:
Auto downloding yet to be configured, presently it is manual
download
Pending
6 GPS is not available. TSGENCO informed that PST feeder protection
relays are time synchronised with Generating station GPS.Other feeder
relays are not time synchronised and procurement of GPS is under
progress.
Mail dated 30.01.2018:
GPS Commissioned. All relays are synchronized.
Complied
7 400kV Switchyard Field
Equipments
Lightning protection (LA's) Earthing is not done as per standards/ NFPA
in the most of 400kV bays. LA's (system) earthing is connected to earth
electrodes directly as well as through equipment earthing.
Mail dated 30.01.2018:
LA's Earthing is provided with Earth mats seperately and these
mats are connected to system earth.
Complied
8 Emulsifier system for fire fighting of Phase Shifting Transformer is not in
healthy condition and Local indication are not available.
Mail dated 30.01.2018:
Rectified Emulsifier System.
Complied
1 (iii) 400 kV KTPS (Stage-VI) [14-16 March, 2016]
11/70
Annexure-VI
Page 11 of 70
9 Oil leakage is observed in PST shunt and series transformer inlet pipelines
to tank.
Mail dated 30.01.2018:
Attended and Rectified
Complied
10 Drainage system in switchyard is not properly maintained.Water logging
in cable trenches has been observed and submerged drain pump also not
in working condition.
Mail dated 30.01.2018:
Pumps are working found Normal
Complied
11 PST-Shunt HV side WTI meter is not calibrated. Mail dated 30.01.2018:
Calibrated
Complied
12 Bay identification codes/name and phase identification are not visible. Mail dated 30.01.2018:
Name plate Boards are fixed with new one.
Complied
13 Walkie-talkie system for communicating with Control room personnel is
not provided.
Mail dated 30.01.2018:
Provided Walkie-Talkies
Complied
Sl. No. Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
1 Mail dated 19.03.2018:
Implemented
Complied
2 Mail dated 19.03.2018:
Revised
Complied
3 Mail dated 19.03.2018:
Already ensured.
Complied
4 Mail dated 19.03.2018:
As per ramakrishna committee recommendations, revised to All
zones blocking except zone-1.
Complied 1
5 Mail dated 19.03.2018:
Already ensured.s
Complied
6 Mail dated 19.03.2018:
AR feature implemented for all 220KV Feeders, except 220KV
Pargi-1 &2 . The work is under progress, will be implemented by
Pending
7 Mail dated 19.03.2018:
Auto Change over is provided.
Complied
8 Mail dated 19.03.2018:
Only one BUS Bar C.U. is enough as per the existing philosophy
Complied
9 Mail dated 19.03.2018:
Will be implemented in 15days.
Pending
10 Mail dated 19.03.2018:
Under progress. Will be implemented in coordination with
remote end substations within 2 months.s
Pending
11 Mail dated 19.03.2018:
Already ensured
Complied .
Remarks/Deficiences/Nonconformity observed
KPCL
The existing Power Swing Philosophy (with all Zones blocked for unblocked time delay) to be reviewed to adopt either of the
following two approaches:
(i) Zone-1 --> Trip; Highers Zones --> Block for a delay of unblocking time delay (2 sec) & then Trip
(ii) Block all Zones with Out-of-Step tripping enabled at electrical zero locations by carrying out required system studies.
Load Encroachment feature, though explicitly not available in P444, has been taken care of by maintaining sufficient marign
beween Zone-4 resitive reach and expected load resistance.
Auto-Reclosure feature in 220 kV lines may be provided as decided in SRPC meetings
Provision of auto supply changeover to BBP may be explored
Bus Bar protection at each ovoltage level (220 kV/ 400 kV) for all Zones has been provided in P741 relay
VT Fuse File operation to be made independent of Over Current (67) functionality in Main-I & Main-II relays of all 400 kV & 220 kV
feeders. Case my be referred to OEM, if required.
VT Fuse fail time delay, which has been presently kept at 0.8 sec, may be suitably revised to say 0.5 sec
Drop-Off to Pick-up ratio of Over-Voltage functionality of Main-I & Main-II relays to be ensured at > 0.97.
Provsision for auto-starting of DG set shall be provided
In 400 kV lines, distance protection timings for Zone-2, Zone-3, Zone-4 and Zone-5(reverse) may be reviewed in line with
Ramakrishna Committee guidelines
High-set operation of ICT's may be checked to ensure their non-operation for downstream/ upstream faults
1) 400/220 kV Shankarapally SS [20 - 21 March, 2017]
TSTRANSCO
12/70
Annexure-VI
Page 12 of 70
Sl. No. Bay name/Bus Voltage Protection/Element/
Equipment/ System
auditated
Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
1 Main-1 &
Main-2 Bus
220KV Protection Single Bus operation is being done for 220kV Switchyard. Two main
Buses (1 Working + 1 Standby) to be provided in the 220KV.
Mail dated 21.02.2018:
Time frame is requested for 2 yrs. To carry out 220Kv double
bus operation using Num relay under PSDF funds
Pending
2 All Line Feeders 220KV Protection Carrier Protection was kept off in all 220KV feeders. PLCC provided in
220KV feeders. KPCL informed that retrofitting of new 48V DC system is
under progress.
Mail dated 21.02.2018:
The retrofitting of new 48V DC system was completed during
July-2016. PLCC system in RTPS is monitored and maintained by
KPTCL. At present KPTCL staff are working on the PLCC system.
Pending
3 ICT-2 220KV Earthmat Resistance Earth resistance values of earth pit of lines were observed to be higher. Mail dated 14.02.2018:
M/s CPRI was awarded the work of earth mat adequecy study at
220/400KV switchyard. Their conclusion is as follows. "A detailed
study of earth resistance measurment, checking the adequacy of
existing earthing system and step and touch potential
measurment was made at RTPS. from the measurment results,
the interconnected earth resistance is found to be 0.05ohm
which is less than the standard value of 0.5ohm for a large
earthing system. soil resistiviy at the side near the switchyard is
found to be homogenous with an average value 30.02ohm-m.
step and touch potential were made found ti be within the
tolerable value. Adequacy checks have been made at all the
locations of RTPS"
Complied
4 Lingasugear -3,
Sadam-1&2
220KV Equipment Wave Trap is not available Mail dated 14.02.2018:
Wave traps are normally provided and commissioned by M/s
KPTCL. However the same is being processed by CEED/CETD
under PSD fund.
Mail dated 21.02.2018:
Wave traps are normally provided and commissioned by M/s
KPTCL. However the same is being processed under PSD fund.
Time frame is requested for 2 yrs.
Pending
5 General 400KV &
220KV
Control room Fire alarm/detection system is not working in 400KV & 220KV control
room. KPCL informed that retrofitting is under progress.
Mail dated 14.02.2018 & 21.02.2018:
Action has been taken for retrofitting works.
Pending
6 SHAHAPUR-1&2 220KV Protection Its observed that the Only one Main relay is used in the 220KV Shahapur-
1&2 (ABB REL100 in Shahapur-2 line feeder and ENGLISH ELECTRIC -
QUADRAM40 in Shahapur-1 line feeder). These relays are very old one
and static type. There is no reverse Zone selection in these relays and
Only one DC source is being used
Mail dated 21.02.2018:
The old Distance Protection relays of Shahapur 1&2 lines were
retrofitted with Numerical relays during July-Aug 2016. ABB
REL511 for Main-I and Alstom MiCOM P444 for Main-II distance
protection.
Complied
7 Raichur-1&2,
Lingasuguar-1&2
220KV Protection In Raichur-1&2 and Lingasuguar-1&2 220KV line feeder DEF provided
only in the Main-2 relay.
Mail dated 21.02.2018:
ABB REL511 and MiCOM P444 relays are in service for Raichur-
1&2 and Lingasuguar-1&2 lines as Main-I & Main-II Dist. Protn.
respectively. DEF is provided in the Main-2 relay and the same
will be enabled in the Main-I relay after retrofitting old REL511
relays with latest version numerical relays under PSDF funds.
Time frame is requested for 2 yrs.
Pending
1) 400 Raichur TPS & 220 kV Raichur TPS [8-10 June, 2016]
13/70
Annexure-VI
Page 13 of 70
8 Lingasuguar-3,
Sadam-1&2
220KV Protection DEF not enabled in Main1&2 relay in the Lingasuguar-3, Sadam-1&2 line
feeder. Separate Earth Fault relay (static type) provided.
Mail dated 21.02.2018:
DEF is enabled in MiCOM P444 (Main-II Dist. Protn.) relay and
also separate ABB make E/F relay RAPDK is existing.
Complied
9 Line Feeders 220KV Protection Auto-reclose feature is not enabled for 220kV lines. Mail dated 21.02.2018:
Auto-reclose function is configured and tested for all the nine
lines in Main-II numerical relays. At present, as per the
requirement of KPTCL, Auto-reclose function is disabled.
Pending
10 General 400KV &
220KV
Equipment It was observed that stand alone Disturbance Recorder with automatic
downloading facility to centralized PC not provided for static relays.
Mail dated 14.02.2018 & 21.02.2018:
Tender has been invited for retrofitting work of balance static
relays with Numerical protection relays and will be completed by
June-2018. Budgetary offer obtained for Retrofitting of stand
alone Disturbance recorder and is under process.
Pending
11 General 220KV Equipment No time Synchronisation in the 220KV system, GPS not avilable. Mail dated 21.02.2018:
GPS system was installed during Aug-2016
Complied
12 Bus Bar 400KV Equipment Two Main zones are available for busbar protection of 400kV Bus-1 and
Bus-2. No check zone is available.
Mail dated 14.02.2018 & 21.02.2018:
Action has been taken for Retrofitting of Numerical Bus bar
protection relays and the same will be reviewed and will be
completed by December 2018.
Time frame is requested for 2 yrs.
Pending
13 Raichur PG-1 &2 400KV Protection Resisitive reach is set at a higher value in 400KV Raichur PG-1 & 2
feeder, Load encroachment is not available.
Mail dated 14.02.2018:
As per PGCIL directions, Revised settings for resistive reach and
load encroachment have been uploaded on 24-06-2016.
Complied
14 Raichur PG-1 &2 400KV PLCC Its observed that the channel failure alarm indication in Raichure PG-2
line Chennel-1 & Raichure PG-1 line Channel-1&2.
Mail dated 14.02.2018:
Same has been set-right and both the channels of Raichur PG-1
& 2 are healthy.
Complied
15 ICT Protection Backup over current and earth fault protection of ICT's is kept non-
directional.
Mail dated 14.02.2018:
Settings will be revised in co-ordination with KPTCL & OEM.
Mail dated 21.02.2018:
Settings will be revised in co-ordination with KPTCL & OEM
during annual shut down of respective equipments.
Pending
16 All Line Feeders 400KV Protection Stub protection Kept off in 400KV lines Main-1&2 relays. But Separate
relay (Static type) provided for the same. Stub protection set value as
0.2A and time delay is instantaneous.
Mail dated 14.02.2018 & 21.02.2018:
Tender has been invited for retrofitting work of the balance
static relays with Numerical protection relays in which enabling
of stub protection is included and the will be completed by June-
2018.
Pending
17 Mehaboob nagar &
Munirabad
400KV Protection Auto reclose is not provided for Tie breaker of 400kV Munirabad &
Mehaboob Nagar lines. Pole discrepancy (PD) for Munirabad & Mehaboob
Nagar Tie-CB is kept as 0.1sec.
Mail dated 14.02.2018 & 21.02.2018:
Tender has been invited for retrofitting work of the balance
static relays with Numerical protection relays in which enabling
of Auto reclose of Tie breaker of Munirabad & Mahbubnagar line
is included and will be completed by June-2018.
Pending
14/70
Annexure-VI
Page 14 of 70
18 Distance protection adopted resistive reach setting for Zone-2 & 3 is not
matching with the recommanded setting given by Tractebel based on
Ramakrishna committee recommendations (Task force committee
guidelines).
Mail dated 14.02.2018:
As per PGCIL directions, revised settings for resistive reach of
Zone-2 & 3 have been uploaded on 24-06-2016 for Raichur PG-1
&2 lines--Completed
Complied
19 Zone-3 time delay is kept as 1.5 sec. Mail dated 14.02.2018:
As per PGCIL directions, revised settings for Zone-3 time delay
as 1.5 sec kept on 24-06-2016 for Raichur PG-1 &2 lines--
Completed
Complied
20 Zone-4 time delay is kept as 1.6 sec. Mail dated 14.02.2018:
As per PGCIL directions, revised settings for Zone-4 time delay
as 0.5 sec kept on 24-06-2016 for Raichur PG-1 &2 lines--
Completed
Complied
21 Directionnal Earth Fault setting kept different in Main 1 & Main 2 Relay Mail dated 14.02.2018:
As per PGCIL directions, Revised settings have been uploaded
on 24-06-2016.The settingsof Directional Earth fault kept same
in Main 1 & 2 relays --Completed
Complied
22 YTPS 400KV Protection Zone-4 time delay is kept as 1.0 sec Mail dated 14.02.2018 & 21.02.2018:
Settings will be revised in co-ordination with KPTCL & OEM
during annual shut down of respective equipments.
Pending
23 MEHABOOB NAGAR
& MUNIRABAD
400KV Protection Zone-4 time delay is kept as 1.1 sec. Mail dated 14.02.2018 & 21.02.2018:
Settings will be revised in co-ordination with KPTCL & OEM
during annual shut down of respective equipments.
Pending
24 MEHABOOB
NAGAR,
MUNIRABAD, YTPS
and All 220KV Line
feeder
400KV &
220KV
Protection In distance protection the adopted resistive reach setting for Zone-1,2 &
3 is not matching with the recommanded setting given by Tractebel
based on Ramakrishna committee recommendations (Task force
committee guidelines).
Mail dated 14.02.2018 & 21.02.2018:
For 220kV lines, the settings recommended by CEERT, KPTCL is
adopted. For 400kV lines, Settings will be revised in co-
ordination with KPTCL & OEM during annual shut down of
respective equipments.
Pending
25 Zone 4 reach should be set to cover 50% of shortest line connected in
RTPC SS (existing settings are set to 20% of protected line)
Mail dated 14.02.2018 & 21.02.2018:
For 220kV lines, the settings recommended by CEERT, KPTCL is
adopted. For 400kV lines, Settings will be revised in co-
ordination with KPTCL & OEM during annual shut down of
respective equipments.
Pending
26 Resistive reach of reverse Zone is not Kept identical with Zone 3 resisitive
reach.
Mail dated 14.02.2018 & 21.02.2018:
For 220kV lines, the settings recommended by CEERT, KPTCL is
adopted. For 400kV lines, Settings will be revised in co-
ordination with KPTCL & OEM during annual shut down of
respective equipments.
Pending
27 Zone-4 (Reverse Zone) time delay not match with Zone-2 setting. Mail dated 14.02.2018 & 21.02.2018:
For 220kV lines, the settings recommended by CEERT, KPTCL is
adopted. For 400kV lines, Settings will be revised in co-
ordination with KPTCL & OEM during annual shut down of
respective equipments.
Pending
All Line Feeders 400KV &
220KV
Protection
Raichur-1&2 400KV Protection
15/70
Annexure-VI
Page 15 of 70
28 General - DC system In DC system +ve Earth fault was observed in 220KV switchyard. The
voltage measured values are :
DC-1
+ve to -ve = 234.6V
+ve to earth = 1.217V
-ve to earth = 233.4V
DC-2
+ve to -ve = 235.3V
+ve to earth = 1.580V
-ve to earth = 233.7V
Mail dated 21.02.2018:
Positive dead ground was partially eliminated in Oct-16. The
voltage measured values were:
+ve to -ve = 237.7V
+ve to earth = 154.8V
-ve to earth = 84.3V
The DC grounding problem is being attended as and when it
appears. The DC voltage measured values in Jan-18 are:
+ve to -ve = 237.7V
+ve to earth = 136.8V
-ve to earth = 107.6V
Pending
29 Mahaboob Nagar
Line Reactor
400KV Equipment Oil seepage was observed in the 400 kV system Line Reactor. Mail dated 14.02.2018:
Oil leakage was arrested during AOH works of M.Nagar line Dec
2016.
Complied
30 General 415V ACDB It is observed that manual Changeover arrangement only has been
provided between Incomer -1 & Incomer-2 feeder in ACDB.
Mail dated 14.02.2018 & 21.02.2018:
It has been deliberated and opined that manual changeover is
adequate.
Pending
31 General 415V DG set Generation plant emergency DG set is utlised for 400KV auxiliaries during
main source blackout. Manual changeover arrangement only has been
provided in the ACDB Main source and DG source.
Mail dated 14.02.2018 & 21.02.2018:
It has been deliberated and opined that manual changeover is
adequate.
Pending
32 General 415V DG set No dedicated DG set for 220KV switchyard auxiliaries. Emergency power
source not provided in the 220KV system ACDB during main power
supply blackout.
Mail dated 14.02.2018 & 21.02.2018:
Tender has been floated for the work of extension of AC supply
from DG-1 Bus to 220KV switchyard auxillaries.
Pending
33 General - Equipment Cables laying in 220KV Switchyard ACDB & DCDB room is observed to be
overloaded in cable trays and some of the cables laid haphazardly (not
properly laid in Cable trays)
Pending
34 General - Equipment In ACDB & DCDB, no Indication Lamps were provided. Mail dated 14.02.2018:
Fused out Indicating lamps replaced.
Complied
35 General - DC system It is observed that dedicated one no. 220V DC system provided in the
220 KV DC auxiliaries. For other DC supply, Generation plant DC source is
being used.
Mail dated 21.02.2018:
For protection of 220kV feeders, one dedicated 220V DC system
is provided and arrangement is ready to take either of Unit 1, 2,
3 & 4 station 220V DC as a backup.
Pending
36 General - Equipment Most of the circuit breaker cubicles in 400KV & 220KV feeders have not
been provided with panel lamp. Door switches were also not working
properly.
Mail dated 14.02.2018:
Panel lamps have been provided and are visible from the front
side of the panel. Failed door switches are being replaced.
Complied
37 General - Equipment It is observed that single earthing has been provided for few marshalling
boxes in switchyard. Also Door earthing was not provided for few
marshalling boxes. The dummy gland holes in few marshalling boxes
were not covered.
Mail dated 14.02.2018:
One more earthing has been provided to marshalling boxes
wherever they were not existing. Door earthing works
completed. Dummy gland holes are plugged with M seal and
Putty.
Complied
38 General - Equipment It was observed that most of unused cutouts in ACDB & DCDB (both 400
kV & 220 kV) in control room were not covered.
Mail dated 14.02.2018:
Unsed cut outs covered with dummy fuse carriers.
Complied
39 General - Equipment Drainage system in switchyard is not properly maintained.Water logging
in cable trenches has been observed and submerged drain pump not
available.
Mail dated 14.02.2018:
This has been brought to the notice of EEPCM2/CCET.
Mail dated 21.02.2018:
The problem will be attended in co- ordination with civil
engineers.
Pending
16/70
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40 General - Equipment It is observed that Silicon coating of 400KV bay equipments not provided. Mail dated 14.02.2018 & 21.02.2018:
Silicon coating of two breakers of Unit-8 has been completed.
Other breakers are under consideration and HO approval
awaited.
Pending
41 General Equipment It is observed that REL500 series relays are not having time
synchronisation facility.
Mail dated 21.02.2018:
Proposed to retrofit old REL511 relays with latest version
numerical relays under PSDF funds. Time frame is requested for
2 yrs.
Pending
Sl. No. Bay name/Bus Voltage Protection/Element/
Equipment/ System
auditated
Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
1 Ambewadi-1 Line
Feeder
220KV Equipment Wave Trap is not available. Mail dated 07.02.2018:
Wave traps provided to R & B phases of all the eight lines.
Complied
2 Synchro-check protections not enabled for Line Feeders. KPCL informed
that the CVT erection & commissioning works are in progress & wiring is
completed in Relay panel & synchronizing panel. Will be commissioned at
the earliest. Synchronizing relay is available.
Mail dated 07.02.2018 & 21.02.2018:
CVT erection and commissioning works completed. Preparation
of wiring scheme is under progress.
Pending
3 CVT condition is very old and not in proper condition, only R-ph CVT is
present in all the lines except Ambewadi line#1 which is not having any
CVT. KPCL informed that the CVT replacement works are in progress. Will
be commissioned at the earliest
Mail dated 07.02.2018:
CVT's erected and commissioned for R,Y & B phases and wave
traps for R & B phases of all the eight lines.
Complied
4 Kodasali-1&2 Line
Feeders
220KV Protection It is observed that the ENGLISH ELECTRIC - QUADRAMHO relay is used
in the Kodasali-1&2 Line feeders Main-I. These relays are very old one
and static type. KPCL informed that the same will be replaced with in one
month.
Mail dated 07.02.2018:
Replaced by new Schneider make micom P444 numerical relays
in both Kodasalli lines 1 & 2.
Complied
5 All Line Feeders 220KV Protection Auto-reclose feature is not enabled for all 220kV lines. Mail dated 07.02.2018 & 21.02.2018:
Auto reclose feature is tested at Nagjhari end along with KPTCL
RT, Hubli and is clear for all the six lines (NA-1, NA-2, NH-1, NH-
2, NH-3, NB). Auto reclose function will be enabled after getting
clearance from the receiving end.
Pending
6 All Line Feeders 220KV Protection Pole discrepancy (PD) for all 220KV Line feeders CB is kept as 0.5sec. Mail dated 07.02.2018 & 21.02.2018:
Will be changed after enabling Auto reclose function to 1.7 Sec.
Pending
7 Reverse Zone Not Enabled in the Kodasali-1&2 and Ambewadi-1&2 Line
feeders.
Mail dated 07.02.2018:
Enabled in Kodasalli lines 1 & 2 and Ambewadi lines 1 & 2 as per
the recommended settings of CEE RT & R & D, KPTCL.
Complied
8 Zone-4 time delay is kept as 2.0 sec. Mail dated 07.02.2018 & 21.02.2018:
As per the recommendations of CEE RT & R & D, KPTCL, Zone-4
trip timing is set to 1 second.
Pending
9 Reverse Zone enabled only for alarm not for trip. Mail dated 07.02.2018:
As per the recommendations of CEE RT & R & D, KPTCL, Zone-4
(reverse zone) is enabled for trip also.
Complied
10 Zone-4 time delay is kept as 1.2 sec Mail dated 07.02.2018 & 21.02.2018:
As per the recommendations of CEE RT & R & D, KPTCL, Zone-4
trip timing is set to 1 second.
Pending
Bidnal Line feeder 220KV Protection
2) 220 kV Nagjheri PH [14-16 July, 2016]
All Line Feeders 220KV Protection
Kodasali-1&2 and
Ambewadi-1&2 Line
feeders
220KV Protection
17/70
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Page 17 of 70
11 Line length is confirmed as 65Kmtrs instead of 69Kmtrs. Mail dated 07.02.2018:
As per the recommendations of CEE RT & R & D, KPTCL, length
of the protected line is set to 67.6Km.
Complied
12 Hubli-1,2 & 3 Line
Feeders
220KV Protection Zone-4 time delay is kept as 1.2 sec Mail dated 07.02.2018 & 21.02.2018:
As per the recommendations of CEE RT & R & D, KPTCL, Zone-4
trip timing is set to 1 second.
Pending
13 Distance protection's adopted resistive reach setting for Zone-1,2 & 3 is
not matching with the recommanded setting given by Tractebel based on
Ramakrishna committee recommendations (Task force committee
guidelines).
Mail dated 07.02.2018:
Settings in all the feeders are made as per the recommendations
of CEE RT & R & D, KPTCL.
Complied
14 Zone-3 time delay is kept as 0.52 sec. Mail dated 07.02.2018:
Zone-3 time delay is set as 800msec as recommended by CEE
RT & R & D, KPTCL.
Complied
15 Zone 4 reach should be set to cover 50% of shortest line connected in
Nagjhari SS ( existing settings are set to 20% of protected line)
Mail dated 07.02.2018:
Settings recommended by CEE RT & R & D, KPTCL are such that
reverse zone covers 20% of the protected line or 50% of the
shortest reverse line impedence whichever is less.
Complied
16 Resistive reach of reverse Zone is not kept identical with Zone-3 resisitive
reach.
Mail dated 07.02.2018 & 21.02.2018:
Settings in all the feeders are made as per the recommendations
of CEE RT & R & D, KPTCL.
Pending
17 Bus bar Protection 220KV Protection Bus bar protection main & check relay are connected to same CT core, 4
Cores are available.
Mail dated 07.02.2018 & 21.02.2018:
Procurement of 5 core CT is under process.Time frame is
requested for 2 yrs.
Pending
18 Hubli-3 and
Kodasali-1&2 Line
Feeders
220KV Protection Carrier Protection is not working in Hubli-3 and Kodasali-1&2 Line feeder.
KPTCL informed that due to CVT & Wave Trap problem carrier protection
are not working, New CVT erection & commissioning works are in
progress & wiring is completed in PLCC panel. Will be commissioned at
the earliest.
Mail dated 07.02.2018 & 21.02.2018:
CVT's and wave traps are commissioned and the carrier
protection is working.
Pending
19 All Line Feeder 220KV PLCC There is provision for one PLCC Channel (Protection & Speech) for each
220 kV double circuit lines.
Mail dated 07.02.2018:
Provision available for both speech & protection for each line.
Complied
20 Bus Bar
sectionaliser
Breakers
220KV LBB Protection LBB protection is not provided for the sectionaliser breakers (Two Nos.) Mail dated 07.02.2018 & 21.02.2018:
Will be implemented in future.
Pending
21 All Line feeders
(Except Kodasali-
1&2 Line feeder)
220KV Protection Main-I & Main-II relays found to be of same type & make for all 220 KV
Line feeders except Kodasali-1&2 line feeders. KPCL informed that the
same is replaced with in one month.
Mail dated 07.02.2018:
Main-II distance protection relays in all the lines are replaced
with Schneider make Micom P444 numerical distance protection
relays.
Complied
22 General 220KV Control room Fire alarm/detection system is not provided in the 220KV control room. Mail dated 21.02.2018 & 21.02.2018:
Will be taken up during SCADA implimentation
Pending
23 General 220KV Equipment Time Synchronisation is not working in the 220KV line feeders, due to
GPS failure. KPCL informed that the GPS equipment will be replaced
within one month.
Mail dated 07.02.2018:
New GPS system is already commissioned and all the numerical
relays are time synchronized.
Complied
Bidnal Line feeder 220KV Protection
All Line Feeders 220KV Protection
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24 General - DC system It is observed that, even though two DC system is available in the
generation plant, both the sources are connected to common bus and
single DC power supply distribution to 220KV SS DC auxiliaries (Field
equipments & Relay panels). The Measured DC Voltage (V) (At farthest
point of the yard):
DC Voltage:
+ve to -ve = 253.1V
+ve to earth = 201.0V
-ve to earth = 52.1V
Mail dated 07.02.2018 & 21.02.2018:
OEM has been approached for providing redundancy in already
existing two separate 250 V DC sources.
Pending
25 General 415V ACDB It is observed that Only one Incoming power supply in 415V ACDB. Mail dated 21.02.2018 & 21.02.2018:
Will be taken up shortly.
Pending
26 General 415V DG set Generation plant 415 V emergency DG set is utlised for 220KV SS
emergency auxiliaries during main source blackout. DG set start in
Manual mode. Also, Manual changeover arrangement only has been
provided in the ACDB Main source and DG source.
Mail dated 07.02.2018 & 21.02.2018:
Procurement of AMF panel is under process.
Pending
27 General - 48 V DC system It is observed that even though two 48VDC sources are available in the
generation plant, both the sources are connected to common bus and
single DC power supply distribution to PLCC panel. No redundancy.
Mail dated 07.02.2018 & 21.02.2018:
OEM has been approached for providing redundancy in already
existing two separate 48 V DC sources.
Pending
28 General - Equipment Most of the circuit breaker cubicles in 220KV feeders have not been
provided with panel lamp. Door switches were also not working properly.
Mail dated 21.02.2018:
Will be taken up shortly.
Pending
29 General - Equipment It is observed that single earthing has been provided for most of the
marshalling boxes and few structures in switchyard. Also Door earthing
was not provided in the most of the marshalling boxes. The dummy
gland holes in few marshalling boxes were not covered.
Mail dated 07.02.2018:
Double earthing provided for all MB's and structures.
Complied
30 General - Equipment The following 220KV Line feeders LA meters are not in working condition.
1.Ambewadi-2 (Y&B-Phase)
2.Hubli-1,2&3 (Y&B-Phase)
3.Ambewadi-1 (Y-Phase)
4.Bidnal (Y&B-Phase)
Mail dated 21.02.2018:
Will be taken up shortly.
Pending
31 General - Equipment Due to aging some of the MBs' door gaskets are worn out and panels
rusted leading to coal dust deposition and vermin ingress in 220KV
S/S.It is advised to replace the MBs/ panels with IP 55/ IP6X panels as
soon as possible.
Mail dated 21.02.2018:
Will be taken up shortly.
Pending
Sl. No. Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
3) 220 kV Sharavathy GS [30 - 31 October, 2017]
Deficiences/Nonconformity observed
19/70
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Page 19 of 70
1 Mail dated 07.02.2018 & 21.02.2018:
(i) Vegetation and weeding cleaned - Jelly spreading work will
be taken up after strengthening / modification works of the
Station Earth mat at SGS.
(ii) Covering of cable trenches by checker plates/concrete blocks
is under progress. Dressing of routed cables done
(iii)Work is under progress, almost 70% of work is completed.
(iv)Door to Panel earthing made for all Marshalling boxes
(wherever not provided) - work completed
(v) Equipment labeling work is under progress.
Pending
2 Mail dated 07.02.2018 & 21.02.2018:
Work of Re-enforcement of equipment supporting (RCC)
structures is in progress.
Pending
3 Mail dated 07.02.2018:
The other bus can be used as suggested only when there is no
maintenance on the spare bus /isolators connected with it. Since
there will be maintenance work on the spare bus connected bus
/isolators the suggested scheme cannot be used for safety
reasons.
Complied
4 Mail dated 07.02.2018:
The problem was rectified.
Complied
5 Mail dated 07.02.2018 & 21.02.2018:
Letter written to EE(MRT), KPTCL vide letter No:
EE(controls)J/RT/F10. Awaiting for reply.
Pending
6 Mail dated 07.02.2018 & 21.02.2018:
Letter written to EE(MRT), KPTCL vide letter No:
EE(controls)J/RT/F10. Awaiting for reply.
Pending
7 Mail dated 07.02.2018 & 21.02.2018:
Letter written to EE(MRT), KPTCL vide letter No:
EE(controls)J/RT/F10. Awaiting for reply.
Pending
8 Mail dated 07.02.2018 & 21.02.2018:
Letter written to EE(MRT), KPTCL vide letter No:
EE(controls)J/RT/F10. Awaiting for reply.
Pending
9 Mail dated 07.02.2018 & 21.02.2018:
It has been enabled and checked at the time of
commissioning.It will be enabled immediately after completion of
station Earth Mat strengthening works.
Pending
10 Mail dated 07.02.2018 & 21.02.2018:
It has been communicated to AEE(PLCC) KPTCL,Awaiting for
reply.
Pending
11 Mail dated 07.02.2018 & 21.02.2018:
Proposal raised for replacement of exsisting D.G with new D.G
having the auto mode feature.
Pending
12 Mail dated 07.02.2018 & 21.02.2018:
Protection part has been completed at common
Auxiliary.Transformer and cabling to be done.
Pending
It is observed that some of the existing gantry & equipment supporting (RCC) structures are in dilapidated state. Steps may be
taken to reinforce them suitably.
It is noted that even though the Bus-Configuration for Sharavathy GS has been designed for a full-fledged double-bus operation
with four sections, it is mostly run on single-bus operation with two sections with both the bus-couplers in OPEN condition and the
other bus being used solely as a transfer bus. Steps may be taken to using full-fledged Double Main-Bus system with four
sections instead of the present Single Main-Bus with two sections.
DC earth leakage is observed in both 250 V DC Sources. Steps shall be taken to rectify the same at the earliest.
Time settings and Reactive & Resistive reaches of Z2, Z3, and Z4 (reverse) of distance relays are observed to be not in line with
Ramakrishna Committee guidelines, which may be reviewed appropriately in consultation with KPTCL.
(i) In PSB settings, unblocking time delay for Z2, Z3 may be revised to 2 sec from the present 3 sec.
(ii) VT fuse fail time delay, which has been presently kept as 0.2 sec, may be suitably revised to 0.5 sec.
(i) Vegetation & weeding was observed in switchyard area. Steps may be taken to provide chemically treated PCC flooring, and
then covering it with suitable blue metal spreading in switchyard area. Steps to be taken to maintain proper upkeep of station by
regularly undertaking cutting of weeds, grass & unwanted vegetation growth in the switchyard area.
(ii) Routing of cables for termination in panels in the switchyard should be done systematically employing proper raisers/ trays.
Further, cables & cable trenches in the switchyard should be covered properly.
(iii) Double-earthing to be provided for all metallic structures in switchyard area.
(iv) Door-to-Panel earthing to be provided in various marshalling boxes, whereever not provided.
(v) Equipment labeling for proper phase-sequence may be provided.
Presently, AC auxiliary supply is obtained from Station Aux.Transformers with DG set as back-up. It is also seen that works are
under progress to provide one external AC auxiliary supply (from MUSS, KPTCL, Jog). It is recommended to expedite providing
external AC aux. supply.
Re-Trip feature to be provided for Breaker Failure Protection in Feeders and GT's.
Mode of Carrier-Aided-Scheme for Talaguppa line-3 (of 20 km) may be changed to Permissive Over Reach from the existing
Permissive Under Reach.
It is observed that A/R for all 220 kV lines has been kept out of service due to pending earth-mat strengthening works. Steps shall
be taken to keep A/R in service at the earliest.
It is noted that even though two Channels per Circuit have been provided for PLCC, Card-level redundancy has not been provided
for those channels. Steps shall be taken to provide the same.
It is observed that DG-Set starting is being done manually. Steps shall be taken to provide DG-Set starting in auto-mode.
20/70
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Page 20 of 70
13 Mail dated 21.02.2018:
Measures are taken to maintain records.
Pending
14 Mail dated 21.02.2018:
Will be taken up shortly.
Pending
15 Mail dated 07.02.2018 & 21.02.2018:
Calibration, interfacing with DCS, alarm setting implementation
are in progress.
Pending
16 Mail dated 07.02.2018 & 21.02.2018:
Action is initiated to procure all equipments.
Pending
Sl. No. Bay name/Bus Voltage Protection/Element/
Equipment/ System
auditated
Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
1 Zone-4 time delay is kept as 1 sec. Mail dated 30.01.2018:
Zone-4time delay setting is revised to 0.5 sec
Complied
2 VT supervision time delay is kept as 1 sec. Mail dated 30.01.2018:
VT supervision time delay kept as 5 sec.
Pending
3 Auto-Recloser was kept off. NPCIL Kaiga has raised issues for enabling
Auto-Recloser for these lines.
Mail dated 30.01.2018:
Auto Reclosure is enabled and it is in service
Complied
4 Narendra 1 & 2 400 kv Protection Panel
Main-I relay
STUB time delay is kept as 100 msec Mail dated 30.01.2018:
400kV Narendra-1 &2 bays at Guttur belongs to Power
Grid.Relay settings of these bays are maintained by Power Grid.
Pending
5 JSWEL 400 kV PLCC Observed that Speech panel is out of service. KPTCL is informed restored
by within two months
Mail dated 30.01.2018:
Speech channel is incorporated in PLCC Protection Panel
Complied
6 Protection Panel
Main-I relay
Reverse zone is not available Mail dated 30.01.2018:
ABB make static type Main-I relay is replaced by numerical
distance relay (ALSTOM make ,P442 type) under R&U
project.Reverse zone protection is provided
Complied
7 Protection Panel
Main-II relay
Carrier Protection was kept off Mail dated 30.01.2018:
Carrier protection is restored
Complied
8 Yard Found that No wave Trap is available in this line Mail dated 30.01.2018:
Wave trap is provided
Complied
9 Protection Panel
Main-II relay
DEF function was found off. Mail dated 30.01.2018:
DEF proteection is enabled
Complied
Measurement of earth-resistance values for various earth-pits shall be undertaken periodically as per relevant standards, and
records maintained properly.
In some Units, leakage current indicators of Lightning Arresters on 220KV side are found to be faulty; the same shall be replaced/
rectified.
Vibration monitoring systems of Units with alarm settings to be commissioned fully.
The following equipment shall be purchased for maintenance of various switchyard equipment:
(i) Thermo-vision imaging camera to identify hot spots in yard equipments and transmission lines.
(ii) Dynamic Contact Resistance Meter for Breaker maintenance
(iii) Winding Resistance Meter
(iv) Earth-resitance measuring kit
KPTCL
1) 400/ 220 kV Guttur SS [4-6 May, 2016]
KAIGA-1 400 kV Protection Panel
Main-I relay
Chitradurga 220 kV
Davangaere-2 220 kV
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Page 21 of 70
10 Yard Found that one wave Trap is available in this line. Mail dated 30.01.2018:
Work of providing one more wavetrap is included under R&U
project.
Pending
11 Haveri-1 220 kV Isolator Isolator was not working properly the same has been bypassed.KPTCL
informed the same would be restored with in one month.
Mail dated 30.01.2018:
Faulty isolator has been replaced
Complied
12 Davangaree 1, 2 &
3
220 kv PLCC No separate PLCC Protection panel available for all these 3 lines and
observed that no redundant card available.
Mail dated 30.01.2018:
Carrier protection is availabe for Main-1 relays of all three
lines.One more PLCC panel will be provided during retrofitting of
Main-2 scheme.
Pending
13 Neelagunda 220 kV Yard Found that B phase wave trap is not connected with Line.KPTCL informed
the same would be restored with in one month.
Mail dated 30.01.2018:
Wave trap is connected and normaly is restored.
Complied
14 Protection panel Over Load function was not available. Mail dated 30.01.2018:
Over load protection is provided.
Complied
15 ICT Oil seepage was observed. Mail dated 30.01.2018:
Oil seepage arrested
Complied
16 Bus coupler 220 kV Isolator Found that isolator misalignment in the arcing contacts. KPTCL informed
the same would be be attended with in the one month
Mail dated 30.01.2018:
Misalignment of arcing contacts rectified
Complied
17 Beernahalli-1 400 kV Line reactor Observed DC Voltage (203.6 V) in Isolator marshalling Box. Mail dated 30.01.2018:
Attended. Measured DC Voltage is 218 V in Isolator marshalling
Box.
Complied
18 Bus Reactor 400 kV Protection Panel 5th Harmonic setting is kept as 35% in differential relay. Mail dated 30.01.2018:
5th Harmonic setting is changed to 25% in differential relay.
Complied
19 All 400 kV Lines Auto Reclouser enabled in both Main -1 & 2 of all 400 Kv lines (Expect
Kaiga 1 &2). KPTCL informed presently using inbuilt Auto-Reclouser in
Distance relay itself.
Mail dated 30.01.2018:
Auto Reclosure is enabled in all the 400kV lines. Built in auto
recloser feature is used
Complied
20 Auto Recloser reclaim time delay is kept as 20s. Mail dated 30.01.2018:
Auto Recloser reclaim time delay isrevised to 25 Sec
Complied
21 Zone 4 time delay has been is kept as 1.0 sec except Narendra-1-2 line. Mail dated 30.01.2018:
Zone-4 time delay setting is revised to 0.5 sec
Complied
22 Zone 4 reach setting should be set to cover 50% of shortest line. Mail dated 30.01.2018:
As per KPTCL practice, Zone-4 reach is set to cover 20% of
the protected line or 50% of shortest line reverse whichever is
lower. Z4 reach setting adopted at Guttur is in order
Complied
23 Overvoltage Protection Stage-2 is kept as instantaneous. Mail dated 30.01.2018:
Over voltage function stage -2 time delay set as 100ms
Complied
24 All 220 kV Lines Auto Recloser is not available in all 220 kV Lines Mail dated 30.01.2018:
AR will be enabled during retrofitting of Main-2 distance scheme
under R&U works
Pending
25 Over voltage function is enabled all 220 kV lines. Mail dated 30.01.2018:
Over voltage functionis disabled in all 220kV lines
Complied
ICT-1 & 2 400/
220 kV
Chitradurga 220 kV
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Page 22 of 70
26 No redundant backup distance protection is available in all 200 kV Lines
(Except Chitrdurga and Divanagree-2)
Mail dated 30.01.2018:
Main2 distance protecion is being provided under R&U project.
Required relays are already supplied to the site.
Pending
27 Observed that No redundant DC supply in PLCC panel Mail dated 30.01.2018:
Two set of Batteries and Battery Chargers are available.
Complied
28 All 400 & 220 kV
Lines
All Isolator were working locally electrical and Bypassed (Removed)
electrical interlocks between Circuit Breaker and Isolator.
Mail dated 30.01.2018:
Action will be taken to provide electrical interlock between CB
and isolator in all bays
Pending
29 All 400 & 220 kV
Lines
Fire Fighting is not available in Control Room, Protection Panel Room &
line reactor Yard. KPTCL informed that the same would be installed within
six months.
Mail dated 30.01.2018:
Fire Fighting equipments are available in Control Room and
Protection Panel Room.
Complied
30 Found that redundant Auxiliary Supply is not available Mail dated 30.01.2018:
Two auxillary transformers (1 MVA each ) fed from separate
feeders from different incomers is provided at Guttur
Complied
31 No specific changeover interlock between Normal supply to Emergency
Supply (DG set)
Mail dated 30.01.2018:
Action will be taken to provide interlock during change over
from normal to emergency supply.
Pending
32 Auto changeover facility is not available. Mail dated 30.01.2018:
Action will be taken to provide auto change over facility.
Mail dated 12.02.2018:
In KPTCL system , no LT circuit breaker available for DG set
supply. Onnly switch has been provided.
Pending
33 Walkie-talkie is not available for communication between switchyard and
control room.
Mail dated 30.01.2018:
Dedicated mobile phones are available.
Pending
34 In some of the Marshalling boxes, single point earthing is done. Mail dated 30.01.2018:
Action will be taken to provide one more earthing.
Pending
35 CT/CVT Star grounded done in filed (Expect Kaiga 1 &2) and bus bar
protection done in relay panel.KPTCL informed earthing for Kaiga 1 & 2
to be done filed.
Mail dated 30.01.2018:
Attended. Iall neutral earthing is done at Switchyard.
Attended
36 Most of the BMK's, CB/Isolator MB & gland plates are very old &
corrosion, almost replace condition. Gland plate holes are open in the
most of the MB. KPTCL informed the same would be attended during
R&M
Mail dated 30.01.2018:
R&M scope is yet to be finalised
Pending
37 Few of the MB is door earthing was not done. Mail dated 30.01.2018:
Attended
Complied
38 GPS is not available for Time Synchronisation Mail dated 30.01.2018:
GPS time synchronisation device has been supplied under R&U,
erection and commissioning works will be taken up shortly.
Pending
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39 Ventilation is not sufficient for control & Protection and Battery rooms. Mail dated 30.01.2018:
Exhaust fans are provided in battery room. AC is being provided
to in Control Room.
Complied
40 Salt formation found in Battery Mail dated 30.01.2018:
Salt formation on the battery terminals have been removed.
Also, one battery set has been replaced by new under R&U
work. Replacement ofsecond set of battery bank is under
progess
Complied
41 Main-I & Main-II relays found to be of same type & make for some 400
kV S/S. KPTCL informed that the same would be attended during R&U .
Mail dated 30.01.2018:
M-II relays will be replaced by Seimens make numerical distance
relays. Required relays have been supplied by M/s GE under
R&U. Retrofitting work will be taken up shortly.
Pending
42 DC supervision relay is not available in Control Panel. Mail dated 30.01.2018:
DC supervision relay is available in the relay Panel & DC fail
annunciation has been provided in the control panel.
Complied
43 Measured DC Voltage (V):
DC-1 DC-2
+ to - : 232.2 222
+ to E : 143 132
- to E : 89.1 90
Mail dated 30.01.2018:
Measured DC Voltage (V):
DC-1 DC-2 +
to - : 239.5 236
+ to E : 121.3 120.2
- to E : 117.2 115.4
Complied
Sl. No. Bay name/Bus Voltage Protection/Element/
Equipment/ System
auditated
Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
1 220kV
and
400kV
Control and
Protection Panels
For 400 KV Busbar protection, one main Bus bar protection scheme for
each Bus 1 & Bus 2 available and Check Zone protection is not available
because of static type relay. Redundant Bus bar protection or Check
zone shall be considerd.
Mail dated 30.01.2018:
The work of providing Main-1 and Main-2 Bus Bar protection for
400kV buses is included under R&U project awarded to M/s GE
T&D India Ltd.. Supply of new BBP panels is expected during
February 2018.
Mail dated 12.02.2018:
Main -1 and Main-2 BBP will be commissioned before end of
December 2018.
Pending
2 BFR (LBB) trips and BB protection trip are properly integrated in Trip Bus
(96).
Mail dated 30.01.2018:
In present conditon LBB trip is extended to BB realy thorugh trip
bus sysem
Complied
3 Main 1 & Main 2 relay make and type (Siemens 7SA522) are same in
400kV Hassan, Hiriyur-1 and Hoody-1 lines.
Mail dated 30.01.2018:
Main-1 and Main-2 relays of same make(Seimens) but different
of different type. Main-1 relay is 7SA522 type and main-2 is
7SA513 type.
Complied
4 In Hiriyur-1 line reactor group 2 protection relay (7SA 5101)-Backup
impedance relay is not in service.
Mail dated 30.01.2018:
Procurement of of New Back up Impedence realy is under
process
Pending
2) 400/ 220 kV Nelamangala SS [8–10 February, 2016]
24/70
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5 For 400kV bus bar protection panel, 2 DC sources are available with
selector switch only. Automatic changeover is not provided. KPTCL
informed that the same will be implemented.
Mail dated 30.01.2018:
This observation will be implemented while commissioning of
new 400 kV Bus bar protection system
Pending
6 Auto-reclose feature is not enabled for 220kV lines. Mail dated 30.01.2018:
AR scheme testing is completed at Nelamangala end during M-II
retrofittng work. M-II retrofitting is pending with remote end sub
stations.Upon completion of M-II retrofitting work at remote
end, AR will be enabled.
Pending
7 220kV
and
400kV
Relay Setting Zone setting & Resistive reach setting for distance protection are found
to be different from the recommanded setting given by Tractebel based
on Ramakrishna committee recommendations (Task force committee
guidelines).
Mail dated 30.01.2018:
Zone reach & resistive reach settings are in line with the
protecion practice followed in KPTCL. Other recommendations
regarding Z4 timing, load angle,stub protection will be adopted.
Pending
8 For all 400 kV lines, stub protection current level and time delay kept as
150% IB and 300 ms against recommended settings of current level of
250% IB and time delay of 50 msec.
Mail dated 30.01.2018:
Stub protection settings will be revised as per the
recommendations
Pending
9 For 400 kV Hiriyur line-2 and Hoody line-2 of model 7SA513 (Main-II),
the relay has the provision to provide only 3 Zones for distance scheme.
Reverse zone is available in Main-1 and not present in Main-II.
Mail dated 30.01.2018:
Reverse zone setting is provided in the M-I relay.
Complied
10 400kV lines (Mysore 1&2,Bidadi 1&2 and Gooty) Zone 2 time is setting as
500ms instead of 350ms.
Mail dated 30.01.2018:
These bays and its relay settings are maintained by PGCIL. To
be attended by PGCIL (SR-II)
Pending
11 Load encroachment feature was not available for 400kV Neelamangala-
Talaguppa line. KPTCL informed that the resistive reach of zone-3 is
limited to less than the Minimum load resistance with a margin of 20%.
Also load encroachemnt feature will be enabled in Main-1 relay after
consultion with OEM.
Mail dated 30.01.2018:
Resistive reach of zone-3 is limited to less than the Minimum
load resistance with a margin of 20%.
Pending
12 DEF is available in one main distance relay in 220kV and 400kV lines. DEF
will not be available in the event of outage of Main distance relay in
which function is enabled.
Mail dated 30.01.2018:
Action will be taken to enable DEF protection in both M-I and M-
II relays.
Pending
13 In Mysore-1&2, Bidadi-1&2, lines over-voltage stg-1 was enabled in Main-
1 distance relay and over-voltage stage-2 was provided through a stand
alone relay. In the event of failure or non-availability of Main- distance
relay only over-voltage stage-2 protection will be available.
Mail dated 30.01.2018:
These bays belong to Power Grid. To be attended by PGCIL (SR-
II).
Pending
14 In 220kV feeders few trippings were observed due to power swing trip
feature provided in Siemens Distance relay (7SA522). It was also
observed that there is no provision for blocking time delay for PSB setting
in distance relay provided for 220kV lines. KPTCL informed that the same
will be taken up with OEM to ascertain the correct reason for tripping and
accordingly modify the PSB setting.
Mail dated 30.01.2018:
Power Swing trip has been disabled in all bays.
Pending
15 220kV
and
400kV
Field
Equipments,ICTs &
Reactors
Lot of Grasses and other weeds are found over the Gravels in the 220kV
and 400kV yard.Weed control by chemical spraying is under process.
Mail dated 30.01.2018:
Switchyard is kept Clean free from Weeds Periodically
Complied
16 In ICT -3 bay, cable PVC conduit are not sealed and exposed to
atmosphere .
Mail dated 30.01.2018:
Action taken to fill the openings of PVC pipes by Bitumen
compound
Complied
25/70
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Page 25 of 70
17 Oil leakage was observed in 400 kV Hiriyur-1line reactor Y-Phase bushing
turret.
Mail dated 30.01.2018:
Oil leakage is arrested
Complied
18 Most of the ICT & reactor conservator tank breather silicagel was in pink
colour.Necessary moisture control action has to be done.
Mail dated 30.01.2018:
Silicagel is replaced.
Complied
19 SF6 leakage was frequently observed in 400kV Hassan-40752 (Nel Make)
and 220kV Nitttur-21852 (Nel make) line breakers. Necessary action has
to be taken.
Mail dated 30.01.2018:
Attended.
Complied
20 In some 220kV/ 400 kV bays, LA surge counters are not in working
condition.
Mail dated 30.01.2018:
Faulty surge counters have been replaced.
Complied
21 For 400kV Gooty line reactor, NGR is not provided. Mail dated 30.01.2018:
Bay belongs to PGCIL (SR-II). To be attended by PGCIL (SR-II).
Pending
22 Emulsifier system for fire fighting of ICT/ LR is not in healthy condition.
KPTCL informed that Nitrogen injection system will be provided.
Mail dated 30.01.2018:
All the ICT's and Line Reactors are provided with CTR make
Nitrogen Injection Fire Prevention System
Complied
23 Walky takie is not available for communication between switchyard and
control room.
Mail dated 30.01.2018:
Dedicated mobile phones are available.
Pending
24 Smoke detection system is not in heathy condition for control room
building.
Mail dated 30.01.2018:
Action is being taken to renovate the Smoke detection System
Pending
25 AC Distribution Auto Changeover is not available in ACDB for 415V Auxiliary supply 1 & 2
and DG set. AMF panel in DG set is not in healthy condition. Supply
Change over operation is carried out manually. Remotely switching ON
of DG is not available from ACDB
Mail dated 30.01.2018:
Action is being taken to provide auto change over of DG system
incase of Auxiliary supply failure
Pending
26 It was observed that one 11kV feeder is available for auxilliary supply of
station. It was informed by KPTCL that 2nd 11kV auxilliary supply will be
made available after commissioning of 66/11kV Sondekoppa substation.
It was observed that there is no automatic chaneover available for
auxilliary supply changeover.
Mail dated 30.01.2018:
Matter Persued with BESCOM officials and separate 11 kV UG
cable from 66kV Sondekoppa Sub station to 400 kV RS
Nelamangala is laid. 66kV Sondekoppa SS is yet to be
commissioned.
Pending
27 DC Distribution 2nos, 220 V DC battery banks with two Battery chargers (one is main
and another is standby). main Battery charger feeds both DCDB-1 & 2
with buscoupler closed.When Main fails standby charger will be 'ON'
manually.
Mail dated 30.01.2018:
M/s Caldyne Make Automatic Float and Boost Charger is
provided, with facility of keeping one in float and another in
Trickle maode. Both the Charger could not be taken on Float
simulatneaous
Pending
28 48 V DC system is also redundant similar to 220 V DC system. Mail dated 30.01.2018:
Loads on both the chargers have been bifurcated.
Complied
29 Protection DC-1&2 (220V) for 220kV and 400kV bays was observed to be
linked at DCDB through 220V bus coupler and same was being extended
to protection relays.
Mail dated 30.01.2018:
M/s Caldyne Make Automatic Float and Boost Charger is
provided, with facility of keeping one in float and another in
Trickle maode. Both the Charger could not be taken on Float
simulatneaous
Pending
30 48V DC-1&2 for PLCC was observed to be linked at DCDB through 48V
bus coupler and same was being extended to PLCC panels.
Mail dated 30.01.2018:
Loads on both the chragers have been bifurcated
Complied
26/70
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Page 26 of 70
31 Communication
system
The System for Auto downloading of disturbance recorders from the
relays is not provided, however manual downloading is done as and when
fault occurred.
Mail dated 30.01.2018:
Remote DR/EL collection system supplied under R&U project will
be commissioned shortly.
Pending
32 SEL , ABB REL 521,EPAC 3000,Reyrolle omegha type relays of 400KV
Mysore 1 & 2, bidadi 1 & 2 lines and Busbar protection relays are not
time synchronised with GPS.
Mail dated 30.01.2018:
The existing CRPs of 400kV Mysore-1 &2,Bidadi-1 &2 and Gooty
bays will be replaced by new CRPs mounted in KIOSKs along
with providng 61850 based SAS & GPS time synchronisation.
The work is entrusted to M/s Shree Electricals Limited
Pending
33 Redundancy is not maintained in Fibre optic equipment. Commisioning of
second set of FOTE is under progress.
Mail dated 30.01.2018:
The work is entrusted to M/s Shreem Electric Limited
Pending
34 One no. PLCC protection coupler availbale for 220kV lines. Mail dated 30.01.2018:
Only One PLCC protection coupler is provided as per the
protection practice followed in KPTCL
Complied
35 General DR is not available for 400kV bus bar protection. DR of 220kV and 400kV
lines not getting triggered with operation of LBB/ Bus bar protection.
220kV bus bar relay not time synchronized with GPS. KPTCL informed
that this will be synchronized.
Mail dated 30.01.2018:
For 400kV Buses, Main-1 and Main-2 Numerical BBP is being
provided under R&U project wherein DR/EL will be available.
Supply of new BBP panels expected during February 2018.
Mail dated 30.01.2018:
Main -1 and Main-2 BBP will be commissioned before end of
December 2018.
Pending
Sl. No. Bay name/Bus Voltage Protection/Element/
Equipment/ System
auditated
Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
1 Bus 220KV System Presently two buses are available with a bus coupler breaker for 220kV
switchyard. Bus bar protection is available for both the 220kV buses and
bus-bar protection is available with two main zone and one check zone.
With the present bus arrangement it is not possible to interchange
feeders between both the buses and shutdown has to be taken in the
event of any maintenance on the line breaker. Provision of additional
220kV bus (transfer bus) which is already proposed in earlier protection
audit will rectify the above issues and improve the reliability of Edamon
station. KSEB has informed that Hybrid switch gear/out door GIS is being
planned for SBEM 2&3, EMKD,EMEP and Transformer 1 & 2 Bays and bus
coupler for accommodating the additional 220kV bus. The work is
scheduled to be completed by Dec 2016.
Mail dated 03.02.2018:
3 Hydrid units are erected commissioned namely SBEM#2 & 3
and Transformer bay #1. Hybrid Bus coupler errected and will
be commissioned subject to line permit availability. The works
on balance namely EMEP, EMKD and Transformer #1 are under
progress and scheduled to be commisioned by March 2018.
Pending
KSEBL
1) 220 kV Edamon SS [18-20 January, 2016]
27/70
Annexure-VI
Page 27 of 70
2 Bus 220KV Protection Single CT core has been used for main and check zone is derived from
same core. KSEB had informed that the bus bar protection would be
replaced during provision of additional 220kV bus. It is proposed to use
separate cores for main and check zone and also to have a redundancy
for bus-bar protection relay for each Bus. A redundant scheme for Bus
protection to be included.
Mail dated 03.02.2018:
Seperate CT cores will be used for Main 1 and Main 2 relays of
newly proposed bus bar protection. Zone trip of Main 1relay +
Check zone of Main 2 relay and Zone trip of Main 2 Relay
+Check zone of Main 1 will be used for Busbar trip decision.
Hence Main and chech zone will be from different CT core
Expected date of completion= June 2018.
Pending
3 Bus 110KV Protection Bus bar protection is not available for 110kV bus at Edamon Mail dated 03.02.2018:
This is being considered. As per present standards, Busbar
protection is not mandatory for 110 kV Bus. The 110 kV Bus at
Edamon is very small.
Pending
4 Kundara and
Edappon
220KV Protection It was observed that DEF and Brocken conductor are enabled in Main-2
distance relay and not enabled in Main-1 distance protection (EPAC 3100)
of Kundra and Edappon feeder.
Mail dated 03.02.2018:
These feeders belongs to PGCIL and action pending with PGCIL
(SR-II).
Pending
5 Tirunelveli-1&2 220KV Protection It was observed that the load encroachment blinder was encroaching
inside zone-1 reach for these feeders which needs review.
Mail dated 03.02.2018:
These feeders belongs to PGCIL and action pending with PGCIL
(II).
Pending
6 Tirunelveli-1&2,
Sabarigiri-1,2&3,
Pothencode-1&2
220KV Protection Tirunelveli-1&2, Sabarigiri-1,2&3, Pothencode-1&2 feeders were having
same Make for Main-1& Main-2 relay (ABB , REL-670). It is proposed to
have different makes for Main-1 & Main-2 relays.
Mail dated 03.02.2018:
Pending for want of CEA's reply. In response to the draft report
of CEA's protection philosophy, KSEBL has forwarded favourable
remarks for maintaining same make Main I & II relays. Hence
this replacement work is in hold, waiting CEA's reply.
Pending
7 Tirunelveli-1&2,
Sabarigiri-1,2&3,
Pothencode-1&2
220KV Protection Reverse zone is not provided in Main-2 distance relays (ABB, REL-670) in
Tirunelveli-1&2, Sabarigiri-1,2&3 and Pothencode-1&2. The same is not
available in the terminal of the relay. The application configured by the
manufacture for three zones only.
Mail dated 03.02.2018:
Zone 4 has been provided for Thirunelveli 1&2 feeders .Offer
from Manufacturer for the Firmware upgradation of SBEM1,2&3
and EMPC 1&2 (to enable Zone 4) . Time synchronization of
Thirunelveli 1&2,SBEM 1,2&3 and EMPC1&2 will be taken up
without delay.
Expected date of completion= June 2018.
Pending
8 ICT-1 220KV /
110KV
Protection HV and LV side backup overcurrent and earth fault protection for
220/110kV ICT-1 is non-directional. It was informed that the time of
operation transformer backup earth fault and over current protection has
been co-ordinated with the 110kV and 220kV line directional earth fault
protection.
Mail dated 03.02.2018:
Rectified
Complied
9 Sabarigiri-1 &
Tirunelveli-1&2
220KV Protection Auto reclose function was tested for 220kv Sabarigiri-1 feeder. Same
was found to be in-order. Auto-reclose function was kept in disable
condition in Tirunelveli-1&2 feeders due to OPGW works.
Mail dated 03.02.2018:
Rectified
Complied
10 Sabarigiri-1,2&3 220KV System Both channel-1&2 of PLCC has been provided in a single PLCC panel for
Sabarigiri-2&3, which are fed from a single power supply module
inside the panel.
Mail dated 03.02.2018:
Now Two DC sources are connected to PLCC panel. Rectified.
Pending
11 Sabarigiri-1&3 220KV Protection Electrical interlock between breaker and isolator is not provided for
the 220kV bays. Manual operation of isolator and earth switch is being
done. Mechanical interlock is provided between earth switch and
isolator and same was verified.
Mail dated 03.02.2018:
Rectified.
Complied
28/70
Annexure-VI
Page 28 of 70
12 ICT-1 220KV /
110KV
Equipment Emulsifier and hydrant system to be provided for firefighting of
220/110kV transformers. Fire prevention wall to be provided between
transformer banks.
Mail dated 03.02.2018:
Form type extinguishers and Fire wall are provided now.
Rectified.
Pending
13 Sabarigiri-1,2&3 220KV Equipment It was observed that the SF6 gas pressure in Sabarigiri-1,2&3 breaker
was not uniform for all the breaker poles.
Mail dated 03.02.2018:
Now SBEM#2 and 3 been replaced by Hybrid switch gear and
SBEM#1 by New SF6 Breaker. Rectified.
Complied
14 ICT-2 220KV /
110KV
Equipment ICT-2 is not in working condition. It was informed that spare
transformer of 200VA will be commissioned
Mail dated 03.02.2018:
It is in Procurement stage.
Expected date of completion= June 2019.
Pending
15 ICT-1 & 2 220KV /
110KV
Equipment Oil sump pit for transformer is not available for ICT. Mail dated 03.02.2018:
Now provided. Rectified.
Complied
16 ICT-1 220KV /
110KV
Equipment Lightening arrestor is not provided on 110kV side of 220/110kV
transformer (ICT-1) . RTCC and cooler control cabinet was observed to
be not in working condition. Provided in the 110 KV Bus and it will be
relocated to transformer.
Mail dated 03.02.2018:
LA are now provided on 110 kV side. RTCC are now in working
condition. Rectified.
Complied
17 AC System 415V System Auxilliary supply from 11kV/0.415kV transformer-1&2 is connected to a
common incomer (breaker) in ACDB panel through a manual
changeover switch. It is suggested to implement auto bus transfer
scheme
Mail dated 03.02.2018:
Now incorporated in the new ACDB which will be installed by
February 2018.
Expected date of completion= February 2018.
Pending
18 DG set 415V Equipment Remote start for DG from ACDB room is not available. AMF panel is
not provided for DG set.
Mail dated 03.02.2018:
New ACDB panel with AMF facility has been procured and will
be retrofitted with the old panel shortly.
Expected date of completion= April 2018.
Pending
19 Sabarigiri-1,2&3 220KV Protection Direct transfer trip is not available and suggested to adopt the same for
all Sabarigiri- Edamon (SBEM) feeders.
Mail dated 03.02.2018:
These features are facilitated in the new protection coupler,
which will be energised in June 2018.
Expected date of completion= June 2018.
Pending
20 Tirunelveli-1&2,
Kundara, Edappon
220KV Protection Power swing block enabled for all zones of Kundara, Edappon and
Thirunelveli (PGCIL owned) feeders.
Mail dated 03.02.2018:
These feeders belongs to PGCIL and action pending with PGCIL
Pending
21 Sabarigiri-1 220KV Protection In the control & relay panel following has been observed:
a) Isolator Earthswitch open indication lamp was not working.
b) Ammeter for R&B phase not working
c) Digital Voltmeter for YB phase not working
d) Digital Frequency meter not working
Mail dated 03.02.2018:
Item (a) Rectified and procurement of the balance is underway.
a) done. b,c & d will be completed in June 2018.
Pending
22 Sabarigiri-2 220KV Protection In the control & relay panel Isolator Earthswitch open indication lamp
was not working.
Mail dated 03.02.2018:
Rectified
Complied
23 Pothencode-1&2 220KV Protection In the control & relay panel Isolator close, Earthswitch open indication
lamp was not workng.
Mail dated 03.02.2018:
Rectified
Complied
29/70
Annexure-VI
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24 Edappon 220KV Protection In the control & relay panel following has been observed:
a) Carrier In/out selector switch Handle is not available
b) Isolator open/close handle was broken
c) Isolator close indication lamp was not working.
d) Old name plate Kayamkulam has to be removed.
c) Annunciator not working
Mail dated 03.02.2018:
These feeders belongs to PGCIL(old C&R panels) and action
pending with PGCIL (SR-II).
Pending
25 Kundara 220KV Protection In the control & relay panel following has been observed:
a) Carrier In/out selector switch Handle is not available
b) Isolator open/close handle was broken
c) Isolator close indication lamp was not working.
Mail dated 03.02.2018:
These feeders belongs to PGCIL(old C&R panels) and
action pending with PGCIL (SR-II).
Pending
26 Tirunelveli-1&2
Kundara, Edappon,
Pothencode-1&2
220KV Protection Zone-4 (Reverse zone) setting should cover 50% of shortest line. Mail dated 03.02.2018:
These feeders belongs to PGCIL and action pending with PGCIL
(SR-II).
Pending
27 Pothencode-1&2,
Sabarigiri-1,2&3
220KV Protection Zone-4 (Reverse zone) time delay has been kept as 1.1sec- For these
feeders for reach setting 50% ( Shortest line in the local Bus) and Z3
resistive reach has been taken as per the recommendation of
Ramakrishne committee. With this setting the faults in the line with
resistive reach of Z3 may be seen by the Z4 of other relays in the bus.
Also the lines are going through forest area and frequent trippings
occured of this nature,hence a time setting which is higher than Z3 is
selected.
Mail dated 03.02.2018:
This matter has been already forwarded to SRPC Awaiting final
report from CEA's Protection philosophy.
Pending
28 Tirunelveli-1&2 220KV Protection Zone-4 (Reverse zone) Fault resistive reach setting not same as Zone-3
resistive reach setting
Mail dated 03.02.2018:
These feeders belongs to PGCIL and action pending with PGCIL
(SR-II).
Pending
29 Tirunelveli-2 220KV Protection Upolmin for Tirunelveli-2 Main-1 relay is set at 20% it should be 1% Mail dated 03.02.2018:
Rectified
Complied
30 Tirunelveli-1&2 220KV Protection t1Min and K1 for DEF is set different in Tirunelveli-1&2 Mail dated 03.02.2018:
Rectified
Complied
31 Tirunelveli-1&2,
Kundara, Edappon
220KV Protection For PSB as per PGCIL recommendation all the zones are blocked Mail dated 03.02.2018:
These feeders belongs to PGCIL and action pending with PGCIL
Pending
32 ICT-1 220KV Protection ICT differential slope setting was observed to be different Mail dated 03.02.2018:
Slope settings adopted as per differential slope equation and
relay manufacture recommendation. Expected date of
completion= June 2018.
Pending
33 ICT-1 & Bus 220KV Protection For ICT-1 single DC supply is available. Mail dated 03.02.2018:
Work in progress .control wiring almost done Will be completed
within February 2018.
Pending
34 General 220KV Protection It was observed that an intentional delay of 1.1 Sec is provided for line
Directional earth fault protection. It was proposed that the directional
earth fault protection should get enabled only in the event of distance
function not able to sense the fault and blocked in the event of pickup of
distance function. No intentional delay is desired for DEF.
Mail dated 03.02.2018:
Needs an edit in application configuration. correction work in
progress for KSEB feeders and for PGCIL feeder correction is
pending with PGCIL.
Expected date of completion= June 2018.
Pending
35 General - - Rusting was observed in lattice structure and bay equipment’s in
Pothencode-1&2 bays. It was informed that the bay will be replaced by
Hybrid switch gear system during the construction of double bus. It was
observed that dummy gland holes in marshalling boxes are not covered.
Mail dated 03.02.2018:
All been replaced by new ones. Rectified.
Complied
30/70
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36 General - Equipment Standby air compressor is not available for breakers with pneumatic
operating mechanism. Rusting was observed in compressor provided in
Sabarigiri-3 breaker.
Mail dated 03.02.2018:
Now this pneumatic system has been completely removed from
the sub station. Rectified.
Complied
37 General - - ANSI numbering system for bays is not provided. Phase identification for
bay not properly done.
Mail dated 03.02.2018:
This will be done on completion of Double Bus construction.
Expected date of completion= June 2018.
Pending
38 General - - Smoke detection system to be provided in control room Mail dated 03.02.2018:
Will be provided.
Pending
39 General - - At present there is no communication facility is available between control
room and yard. Walky-talkie system to be provided for communication
between switchyard and control room for facilitating switchyard
operations.
Mail dated 03.02.2018:
Will be provided.
Pending
40 General - - Auto recloser ON/OFF switch shall be provided separately for all feeders. Mail dated 03.02.2018:
At present, the station Engineer put the Auto-reclosure out of
service, through Laptop/ HMI, when ever such requirement
arises. Hence separate switch is not required in the present
condition. It is requested to drop this item.
Pending
41 General - - Considering the better operation practices the following shall be
considered
a) Operation may be done by SCADA system with remote operation
facility
b) Thermo vision survival cameras with remote viewing to be provided
c) 2 Nos BUS coupler may be provided in the proposed double bus
system
Mail dated 03.02.2018:
(a) This will be considered while an upgradatioin work take
place.
(b) Procurement process started. will be completed in June
2018.
(c) Expected to be completed within June 2018.
Pending
42 General - - The present C&R panels for Edappon and Kundara, Bus Coupler and Bus
Bar are observed as old. Main-1 relay (EPAC 3100) does not have
provision for collecting history of operation and DR.
Mail dated 03.02.2018:
These feeders belongs to PGCIL(old C&R panels) and action
pending with PGCIL (SR-II).
Pending
43 General - - As part of good safety practices the followings may be considered
a) Industrial type switches and sockets for control room
b) Fire exit to be in proper direction
c) LED lightings may be provided as the part of energy conversation
Mail dated 03.02.2018:
The corrective action will be taken in a phased manner.
Pending
Sl. No. Bay name/Bus Voltage Protection/Element/
Equipment/ System
auditated
Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
1 Vallur 400 kV CB Pole discrepancy time delay kept as ber below
i. Line-1 main Circuit Breaker - 2.5 sec,
ii. Tie Circuit Breaker- 2.0 sec,
ii. Line-2 main Circuit Breaker-3.0 sec
Mail Dated 29.01.2018
PD Time set uniformaly as 2.5 Seconds.
Complied
1) 400/ 230 kV Alamathy SS [4-6 January, 2016]
TANTRANSCO
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Sl. No. Bay name/Bus Voltage Protection/Element/
Equipment/ System
auditated
Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
2 NCTPS 1 & 2 400 kV CB Tie Breaker bay not yet commissioned Mail Dated 29.01.2018
Will be commissioned by June-2018.
Pending
3 ICT 2,3,4 & 5 400 kV ICT CB Pole discrepancy time delay kept as ber below
i. ICT-5 - 1.0 sec,
ii. ICT Tie - 1.0 sec
iii. ICT-4 - 0.1 Sec
iv. ICT-2&3 - 2.1 Sec
Mail Dated 29.01.2018
PD Time set uniformaly as 0.6 Seconds.
Complied
4 Thiruvalam & SVC 400 kV CB Switchyard isolator electrical interlocks were observerd to be unhealthy
for 400 & 220 kV system.
Mail Dated 29.01.2018
Line clearance is required for checking the isolator interlocks
which involves all bay isolator and earth switch auxillary
contacts. Will be completed by 31.03.2018.
Pending
5 NCTPS 1 & 2 400 kV Main-II It was observed in Main-2 (D60) Relay that there is provision for enabling
one stage of Over voltage protection. Hence O/V stage-2 has been
enabled in main-2 relay. In the event of outage of main-1 relay only O/V
stage-2 protection will be available.
Mail Dated 29.01.2018
The D 60 Relay have provision for only one element for
overvoltage Stage-I due to design limitation. Two stages of O/V
protection is adopted in Main-I (P543) Relay.
Complied
6 SVC-1&2 230 kV Main-1 & 2 It was observed in main-2 (D60) Relay that there is provision for enabling
one stage of Over voltage protection. O/V stage-1 has been enabled in
main-1 relay and O/V stage-2 in main-2 relay. In the event of outage of
any one main relay only one stage of O/V protection will be available.
Mail Dated 29.01.2018
Main 1 D60 relay replaced in SVC-1 & 2 feeders by P442 relay
on 23.01.2018 & 10.01.2018 respectively. The D 60 Relay have
provision for only one element for overvoltage Stage-I due to
design limitation. Two stages of O/V protection is adopted in
Main-I (P442) Relay.
Complied
7 Korattur &
Thiruverkadu
230 kV Relay panel Carrier Protection for the corresponding Lines were observered not
available. However it was informed that Digital Tele-Protection Coupler is
proposed for the corresponding feeders.
Mail Dated 29.01.2018
The Korattur bay name have been changed as Koyembedu
feeder. The carrier scheme will be established for Thiruverkadu
feeder by 31.01.2018. Fibre Optic link will be established for
Koyembedu feeder.
Pending
8 Manlai-1&2 230 kV Relay panel Auto recloser for the corresponding line is not available. It was informed
the frequent permanent fault prone zone due to chemical pollution at
manalai S/S. Hence ARC not enabled.
Mail Dated 29.01.2018
Manali 230kV AIS was upgraded to 400kV GIS Substation. Cable
portion is involved in the line. Hence, Auto Reclosure for 230kV
Manali - 1 & 2 feeders not enabled.
Complied
9 Korattur 230 kV Relay panel Trip circuit supervision for Trip Coil-1 is not in working condition. It was
informed that replacement of faulty relay is under process.
Mail Dated 29.01.2018
Complied.
Complied
10 General Zone-4 time delay is kept as 1.1 sec in 400 kV Line . Mail Dated 29.01.2018
The Zone 4 time is set at 1.1 sec as per approved guidelines.
Pending
11 General Auto recloser not available for the all 400 kV tie breakers. Mail Dated 29.01.2018
Auto Reclosure scheme for Tie CB enabled in SVC Bay. For Vallur
and Thiruvalam bay, the scheme will be checked during next LC.
Pending
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Sl. No. Bay name/Bus Voltage Protection/Element/
Equipment/ System
auditated
Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
12 General STUB protection not available for 400 kV feeders. Mail Dated 29.01.2018
For enabling of STUB Protection, Line Isolator status from
swithyard is being checked for the scheme. Will be completed by
June-2018.
Pending
13 General Load encroachment is not available in 400 & 230 KV feeders. However it
was informed that the resistive reach have been suitably calculated to
take care of the same.
Mail Dated 29.01.2018
Suitable setting adopted to avoid load encrocachment.
Complied
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Sl. No. Bay name/Bus Voltage Protection/Element/
Equipment/ System
auditated
Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
14 General Observed redundant power supply (48V) not available in RTU panel. Pending
15 General Observed redundant data transfer (to LDC) channel is available however
manual change over is being done in the even of failure of main channel.
Pending
16 General Stand alone Event Locker is not available for the station. Pending
17 General Disturbance recorders in 400 & 230 KV feeders are not time synchronised
with GPS.
Pending
18 General Main-1 & Main-2 relays found to be of same make in 400 kV
S.V.Chattiram Line -1&2 and 230 kV Koratur & Manali -1.
Mail Dated 29.01.2018
Main-1 D60 relay replaced in SVC-1 & 2 feeders by P442 relay
on 23.01.2018 & 10.01.2018 respectively.
In 230kV Manali-1 feeder & 230kV Thiruverkadu feeder, Main-2
P442 relay will be replaced with D60 relay (released from SVC-1
& 2 feeders), by February 2018.
Pending
19 General The Emulsifire fire systems are found to be not erected and commisioned
for ICT-2,4 & 5.
Mail Dated 29.01.2018
Estimate submitted for approval.
Pending
20 General Direct Trip not available for 230kV feeders. This may cause delayed fault
clearances from remote end in the event of operation of LBB protection.
Mail Dated 29.01.2018
CTs are on Bus side. Carrier inter trip scheme is available for
remote end trip.
Pending
21 General Non directional Backup Over current provided in HV/LV side of all
Transformers.
Mail Dated 29.01.2018
Numerical relay procurement is under progress for enabling
Directional O/C & E/F protection.
Pending
22 General Fire detection system is not healthy in control room. Mail Dated 29.01.2018
The healthiness of Fire detection system will be checked to bring
back in to service.
Pending
23 General Walkie-talkie is not available for communication between switchyard and
control room.
Mail Dated 29.01.2018
Walkie Talkies provided.
(Complied).
Complied
24 General Auto changeover is not available in ACDB for 0.415 kV Auxiliary supply 1
& 2. DG set was also observed to be operated in manual mode.
Mail Dated 29.01.2018
The feasibility for auto change over will be studied for
implemetation.
Pending
25 General CB On/Off & Spring Charged Mechanical indications in 230 kV CB are not
visible in switchyard.
Mail Dated 29.01.2018
Rectified. (Complied).
Complied
Mail Dated 29.01.2018
Will be implemented in new RTU which is under procurement
stage.
Mail Dated 29.01.2018
Commissioning of DR & EL collection system alongwith GPS is
under progress.
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Sl. No. Bay name/Bus Voltage Protection/Element/
Equipment/ System
auditated
Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
26 General CB ON/Off and spring charged mechanical Indication functions are not
working in 230kV Manali 1 & 2 feeders circuits
Mail Dated 29.01.2018
Rectified. (Complied).
Complied
27 General Name Plate details on bay Marshalling Box of 230 kV Thiruverkadu feeder
circuit is mismatching
Mail Dated 29.01.2018
Rectified. (Complied).
Complied
28 General Corrosion observed in Earth mat risers and CB/Isolator operating
mechanism boxes , junction boxes and oil conservator tanks of ICTS
Mail Dated 29.01.2018
Estimate will be evolved soon.
Pending
29 General Rusting was observed in CB operating mechanism boxes of 230 kV OPG -
1 & 2 feeders.
Mail Dated 29.01.2018
Rectified.
(Complied).
Complied
30 General For 230 kV feeders for OPG-1&2 and NCTPS bypass isolator (Placed in
gantry) Moving contacts were found to be missing.
Procurement work under progress. Pending
31 General Few Indicating meters in control panel were found to be unhealthy. Mail Dated 29.01.2018
Rectified all except ICT3 & 110kV Avadi-2 feeder.
Pending
Sl. No. Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
1 Mail dated 29.01.2018:
Suitable setting adopted to avoid load encrocachment.
Complied
2 Mail dated 29.01.2018:
LAS Erection and Connecting the earth pit gantry take off Tower
to Station Earth mat Works will be completed in July-2018.
Pending
3 Mail dated 29.01.2018:
Materials supplied and will be commissioned.
Pending
4 Mail dated 29.01.2018:
Proposal has been evolved.
Pending
2) 230 kV Alundur SS [4-6 January, 2016]
Deficiences/Nonconformity observed
Load Encroachment has not been enabled as the the estimated load is much higher than Zone-3 resistive reach
Transmisssion line earthwire earthing was done at earth pit gantry take-off tower, which may be reviewed for connection to station
earth-mat
Lightning Arrestors for all 230 kV feedses are to be provided
Fire protection for 100 MVA, 230/ 110 kV Auto Transformers to be provided
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Sl. No. Bay name/Bus Voltage Protection/Element/
Equipment/ System
auditated
Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
5 Mail dated 29.01.2018:
Metal Spreading will be provided for each Bay.
Pending
6 Mail dated 29.01.2018:
Will be completed by February-2018.
Pending
7 Mail dated 29.01.2018:
Will be completed by February-2018.
Pending
8 Mail dated 29.01.2018:
Commissioning of DR & EL collection system alongwith GPS is
under progress.
Pending
9 Mail dated 29.01.2018:
Commissioning of DR & EL collection system alongwith GPS is
under progress.
Pending
10 Mail dated 29.01.2018:
The Zone 4 time is set at 1.1 sec as per approved guidelines.
Reach settings will be revised during Relay testing.
Pending
11 Mail dated 29.01.2018:
Complied.
Complied
12 Mail dated 29.01.2018:
Will be completed by March-2018.
Pending
13 Mail dated 29.01.2018:
Will be completed by March-2018.
Pending
14 Mail dated 29.01.2018:
Programmed during April-2018.
Pending
Mail dated 29.01.2018:
Estimates sanctioned. Procurement of Digital type meters is
under progress and will be replaced by July-2018.
Mail dated 29.01.2018:
Estimate sanctioned and Procurement is under progress.
Mail dated 29.01.2018:
Estimate is evolved and the works will be completed in July-
2018.
15 Pending
a) All analog meters to be replaced by Digital meter
b) D.G. Set with enhancement of 75 kVA Auto/ Manual control from control room itself (remote operation)
c) Isolator position in control panels
Resistive reach settings for Zone-1, Zone-2 & Zone-3 may be reviewed in line with Ramakrishna Commitee recommendations
DR to be triggerred for LBB and BBP operations
Check-synchronizing relay to be provided in Synchronizing trolley.
Station earth mat resitance was measured to be 0.18 ohm on 07.07.2016
TANTRANSCO informed the following had been been included in the propopsed R & M works:
DC Supply selection changeover switch to be provided in BB panels
Provision for DC supply changeover by a separate coupler switch between the two DC sources may be examined for improving the
reliability.
Time synchronization of various protection relays with GPS was not available. TANTRANSCO informed that GPS facility was under
prcurement stage
Stand alone Event Logger not available. TANTRANSCO informed that GPS facility was under prcurement stage
Zone-4 settings (for reactance reach, resistivee reach and time settings) may be reviewed in line with Ramakrishna Commitee
recommendations
Swtichyard area was observed to be covered with cement flooring. Providing metal spreading may be examined for ensuring safe
touch & step potential limits
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Sl. No. Bay name/Bus Voltage Protection/Element/
Equipment/ System
auditated
Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
Mail dated 29.01.2018:
Estimate is evolved and the Civil works will be completed.
Mail dated 29.01.2018:
Complied.
Mail dated 29.01.2018:
Estimate sanctioned. Procurement is under process and Erection
works will be completed by July-2018.
16 Mail dated 29.01.2018:
Materials supplied and will be commissioned.
Pending
Sl. No. Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
1 Yet to be informed
2 Yet to be informed
3 Yet to be informed
4 Yet to be informed
5 Yet to be informed
6 Yet to be informed
7 Yet to be informed
f) Alarm anunciator panel in all 230 kV feeders, Auto HV - I & II, Bus coupler
15 Pending
Line CVT's to be used for feeder protection by commissioning Y-ph & B-ph CVT's in all 230 kV feeders. TANTRANSCO informed
that the related works had already been taken under PSDE funding.
d) Entire gravel filling in 230 kV & 110 kV yard
e) Extension of Battery room and Carrier room for providing panels
3) 400/ 230-110 kV Palavadi SS [16-17 May, 2018]
Deficiences/Nonconformity observed
Substation is well maintained.
All Circuit Breakers are based on spring (Trip) - spring (Close) operating mechanism.
Time settings and Reactive & Resistive reaches of Z2, Z3, and Z4 (reverse) of distance relays for 400 kV and 230 kV feeders are
observed to be not in line with Ramakrishna Committee guidelines, which may be reviewed appropriately to bring in line with
them.
Re-Trip feature to be provided for Breaker Failure Protection for 400 kV & 230 kV circuit breakers.
Auto-reclosure dead-time may be unformly adopted across all 400 kV and 230 kV feeders as 1 sec.
It is observed that Pole Discrepancy time delay has not been set uniformly. It is recommended to keep PDR time delays as follows:
(i) For all line Main-CB's and Tie-CB's where Aut-Reclosure with priority has been employed with dead-times of 1 sec & 2 sec
respectively, PDR time delay shall be kept as 1.5 sec and 2.5 sec respectively.
(ii) For all other elements, PDR time delay shall be kept as the minimum avaiable in the relay, but not less than 100 msec. This
may be preferably kept as 0.5 sec.
It is seen that 110 kV Dharmapuri and 110 kV Pennagaram lines did not have circuit breaker at remote ends. Steps may be taken
provide them to facilitate proper discrimination of faults.
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Sl. No. Bay name/Bus Voltage Protection/Element/
Equipment/ System
auditated
Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
8 Yet to be informed
9 Yet to be informed
10 Yet to be informed
11 Yet to be informed
12 Yet to be informed
13 Yet to be informed
14 Yet to be informed
15 Yet to be informed
16 Yet to be informed
17 Yet to be informed
18 Yet to be informed
It is found that the furnished values of earth-pit resistance (with and without grid-connected) are at variance with the values
displayed in all (400 kV & 230 kV & 110 kV) switchyards, and have not been measured after commissioning of the same in March,
2017. It is recommended to carry out measurement of earth-resistances of all earth pits (400 kV & 230 kV & 110 kV switchyards)
on yearly basis, and keep updated records with the substation along with suitable earth-mat lay-out diagrams. A copy of the same
may also be furnished to SRPC Secretariat.
It is observed that 110 kV feeders earthwire earthing has been done at respective gantry take-off towers, which may be reviewed
for connection to station earth-mat.
It is seen that REF protection has not been provided for 125 MVAR Bus-Reator, which may be provided.
Directional O/C Protection (high-set & IDMT) and Directional E/F protection (high-set & IDMT) shall be provided on both sides of
400/ 230 kV ICT's and 400/ 110 kV ICT's.
It is seen that the philosophy of Group-A & Group-B Protections has not been followed in case of ICT's. It is recommended to
adopt the same with the following model segregation of protections:
Group-A:
Differential, DOCE (HV), Overflux (HV)
Group-B:
REF, DOCE (LV), Overflux (LV)
It is also recommended to arrange supply for these two groups from two different DC supplies.
It is seen that speech channel has not been provided as part of substation communication in any of the 400 kV & 230 kV feeders.
Steps may be taken to provide the same.
It is observed that Protection Channels of Thiruvalam lines 1 & 2 have been implemented from same DTPC. Similarly Protection
channels of Mettur lines 1 & 2 have been implemented from another DTPC. Steps may be taken to implement protection channels
of each line from one/ two dedicated DTPC's.
It is seen that even though two AC auxiliary supplies are being provided from two different sources (33 kV/ 11 kV Adagapady SS,
and 33 kV/ 11 kV Paparapatty SS), since both these supplies have been derived from the same source substation, viz., 110/ 33 kV
Pennagaram SS, the independency of AC auxiliary supplies is not ensured. It is recommended to provide redundant AC auxiliary
supply from another suitable substation in addition to 110/ 33 kV Pennagaram SS.
It is seen that the provided 100 kVA DG set is insufficient for catering to mandated substation loads. It is recommneded to provide
a DG set of suitable (higher) capacity. Steps may also be taken to maintain sufficient fuel stock to take care of unforeseen
emergencies.
It is observed that DG-Set starting and Supply changeover among AC supplies & DG set are being done manually. Steps shall be
taken to provide them in auto-mode.
It is observed that earth-resistance for some of the 400 kV earth-pits (grid-connected) esp. near ICT's are found to be higher than
the mandated limit of 0.5 ohms. (measured values are found to be varying between 0.4 ohms - 20 ohms). It is recommended to
attend to them on priority basis, and take necessary steps to bring them within the mandated limit of 0.5 ohms.
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Sl. No. Bay name/Bus Voltage Protection/Element/
Equipment/ System
auditated
Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
19 Yet to be informed
20 Yet to be informed
21 Yet to be informed
22 Yet to be informed
23 Yet to be informed
Sl. No. Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
1 Mail dated 30.01.2018 & 13.03.2018:
Existing Control & Relay Panels installed with static relays are
proposed to be replaced with new control panels installed with
numerical relays under the project of Upgradation of existing
static relays and replacement of sub-station equipments at
230KV Villianur and Bahour Auto Sub-Station at the cost of
Rs.10,56,16,191/- through PSDF funding. Tendering process for
award of work on labour contract basis for the above said work
is almost over and waiting for the approval of Puducherry
Government to place order at the lowest tenderer.
Pending
Puducherry ED
1) 230/ 110 kV Villianur SS [10 - 12 July, 2017]
Directional O/C & E/F protections to be provided for 230 kV & 110 kV feeders where Main-II is not provided; Directional E/F
protection to be provided for 230 kV & 110 kV feedes where Main-I & Main-II are provided
Deficiences/Nonconformity observed
It is observed that 110 kV switchyard has been provided with only one lighning mast to provide protection from direct lightning
strokes. It is recommended to provide sufficient no. of lightning masts to cover entire 110 kV switchyard.
The following equipment may be purchased/ provided for maintenance of various switchyard equipment:
(i) Tan delta meaurement kit.
(ii) Digital Earth-resitance measuring kit
A suitable lifting device/ aerial work platform may also be provided and maintained with the substation to carry out testing on
various equipment.
It is seen that Palavadi is a SAS station; however no CC cameras have been provided in the switchyards to exert effctive
monitoring. Steps may be taken to provide the same at suitable locations for better security.
Equipment labeling for proper phase-sequence and Bay Element labeling may be provided in all 400 kV & 230 kV & 110 kV
switchyards.
Walkie-talkie system for yard communication is not available, which may also be provided.
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Sl. No. Bay name/Bus Voltage Protection/Element/
Equipment/ System
auditated
Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
2 Mail dated 30.01.2018 & 13.03.2018:
As per the recommendation of Protection Audit Team, a Detailed
Project Report at the cost of Rs.14,85,42,653.21 has been
prepared to replace the existing aged equipments and provide
additional equipments at 230KV Villianur and Bahour Auto Sub-
Station and sent to higher authority to obtain sanction under
PSDF funding. (copy enclosed)
Pending
3 Mail dated 30.01.2018 & 13.03.2018:
Existing aged Two sets of 110Volt Station Batteries have been
replaced with two sets of new 110Volt Station Batteries. Further,
in addition to the existing one set of 48Volt PLCC battery, one
more 48Volt PLCC Battery has been provided. All the above
three batteries have been commissioned in the last week of
January 2018. Wiring has to be done to segregate the existing
single circuit into two circuits.
Pending
4 Mail dated 30.01.2018 & 13.03.2018:
Existing Control & Relay Panels installed with static relays are
proposed to be replaced with new control panels installed with
numerical relays under the project of Upgradation of existing
static relays and replacement of sub-station equipments at
230KV Villianur and Bahour Auto Sub-Station at the cost of
Rs.10,56,16,191/- through PSDF funding. Tendering process for
award of work on labour contract basis for the above said work
is almost over and waiting for the approval of Puducherry
Government to place order at the lowest tenderer.
Pending
5 Mail dated 30.01.2018 & 13.03.2018:
Protection & Communication wing of TAN TRANSCO Limited,
Villupuram has been requested vide Lr. No.347/ED/EE-Auto
SS/AEE-M-VASS/F-4/2017-18, dated 21.09.2017 for revision of
existing relay settings as per the recommendations of Protection
Audit Team.
Pending
6 Mail dated 30.01.2018 & 13.03.2018:
Protection & Communication wing of TAN TRANSCO Limited,
Villupuram has been requested vide Lr. No.347/ED/EE-Auto
SS/AEE-M-VASS/F-4/2017-18, dated 21.09.2017 for revision of
existing relay settings as per the recommendations of Protection
Audit Team.
PendingZ2 and Z3 (reactive & resistive) reaches & time settings were observed to be not in line with Ramakrishna Committee guidelines,
which may be reviewed appropriately.
Line CVT's to be provided in all phases for all 230 kV lines.
Redundant DC suppy for protection (110 V) and communication (48 V) applications to be provided with requisite segregation in
wiring.
For 230 kV feeders, the present single-zone BB protection is to be reviewed and provided with two-zone operation & Check-zone
operation.
Z4 (reverse) is to be provided in all distance relays of 230 kV & 110 kV feeders
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Page 40 of 70
Sl. No. Bay name/Bus Voltage Protection/Element/
Equipment/ System
auditated
Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
7 Mail dated 30.01.2018 & 13.03.2018:
Protection & Communication wing of TAN TRANSCO Limited,
Villupuram has been requested vide Lr. No.347/ED/EE-Auto
SS/AEE-M-VASS/F-4/2017-18, dated 21.09.2017 for revision of
existing relay settings as per the recommendations of Protection
Audit Team.
Pending
8 Mail dated 30.01.2018 & 13.03.2018:
Protection & Communication wing of TAN TRANSCO Limited,
Villupuram has been requested vide Lr. No.347/ED/EE-Auto
SS/AEE-M-VASS/F-4/2017-18, dated 21.09.2017 for revision of
existing relay settings as per the recommendations of Protection
Audit Team.
Pending
9 Mail dated 30.01.2018 & 13.03.2018:
Protection & Communication wing of TAN TRANSCO Limited,
Villupuram has been requested vide Lr. No.347/ED/EE-Auto
SS/AEE-M-VASS/F-4/2017-18, dated 21.09.2017 for revision of
existing relay settings as per the recommendations of Protection
Audit Team.
Pending
10 Mail dated 30.01.2018 & 13.03.2018:
Protection & Communication wing of TAN TRANSCO Limited,
Villupuram has been requested vide Lr. No.347/ED/EE-Auto
SS/AEE-M-VASS/F-4/2017-18, dated 21.09.2017 for revision of
existing relay settings as per the recommendations of Protection
Audit Team.
Pending
11 Mail dated 30.01.2018 & 13.03.2018:
Existing aged Two sets of 110Volt Station Batteries have been
replaced with two sets of new 110Volt Station Batteries. Further,
in addition to the existing one set of 48Volt PLCC battery, one
more 48Volt PLCC Battery has been provided. All the above
three batteries have been commissioned in the last week of
January 2018. Wiring has to be done to segregate the existing
single circuit into two circuits.
Pending
12 Mail dated 30.01.2018 & 13.03.2018:
Existing Control & Relay Panels installed with static relays are
proposed to be replaced with new control panels installed with
numerical relays under the project of Upgradation of existing
static relays and replacement of sub-station equipments at
230KV Villianur and Bahour Auto Sub-Station at the cost of
Rs.10,56,16,191/- through PSDF funding. Tendering process for
award of work on labour contract basis for the above said work
is almost over and waiting for the approval of Puducherry
Government to place order at the lowest tenderer.
Pending
Auto-reclosure dead-time and reclaim-time for 230 kV feeders may be revised to 1 sec and 25 sec respectively.
Power Swing Philosophy (Z1 --> Unblock; Higher Zones --> Block for 2 sec) is to be adoped unfiromly across all 230 kV feeders.
Load encroachment feature may be appropriately kept enabled in 230 kV & 110 kV feeders.
For 230 kV Pondy feeder POR may be used in place of the existing PUR.
Steps to be taken to ensure that Main-I & Main-II protections or Main & back-up protections of feeders are fed from different DC
supplies.
REF protection to be provided for 100 MVA, 230/ 110 kV ICT-1 & ICT-2.
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Sl. No. Bay name/Bus Voltage Protection/Element/
Equipment/ System
auditated
Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
13 Mail dated 30.01.2018 & 13.03.2018:
Existing Control & Relay Panels installed with static relays are
proposed to be replaced with new control panels installed with
numerical relays under the project of Upgradation of existing
static relays and replacement of sub-station equipments at
230KV Villianur and Bahour Auto Sub-Station at the cost of
Rs.10,56,16,191/- through PSDF funding. Tendering process for
award of work on labour contract basis for the above said work
is almost over and waiting for the approval of Puducherry
Government to place order at the lowest tenderer.
Pending
14 Mail dated 30.01.2018 & 13.03.2018:
Existing Control & Relay Panels installed with static relays are
proposed to be replaced with new control panels installed with
numerical relays under the project of Upgradation of existing
static relays and replacement of sub-station equipments at
230KV Villianur and Bahour Auto Sub-Station at the cost of
Rs.10,56,16,191/- through PSDF funding. Tendering process for
award of work on labour contract basis for the above said work
is almost over and waiting for the approval of Puducherry
Government to place order at the lowest tenderer.
Pending
15 Mail dated 30.01.2018 & 13.03.2018:
Existing Control & Relay Panels installed with static relays are
proposed to be replaced with new control panels installed with
numerical relays under the project of Upgradation of existing
static relays and replacement of sub-station equipments at
230KV Villianur and Bahour Auto Sub-Station at the cost of
Rs.10,56,16,191/- through PSDF funding. Tendering process for
award of work on labour contract basis for the above said work
is almost over and waiting for the approval of Puducherry
Government to place order at the lowest tenderer.
Pending
16 Mail dated 30.01.2018 & 13.03.2018:
Existing aged Two sets of 110Volt Station Batteries have been
replaced with two sets of new 110Volt Station Batteries. Further,
in addition to the existing one set of 48Volt PLCC battery, one
more 48Volt PLCC Battery has been provided. All the above
three batteries have been commissioned in the last week of
January 2018. Wiring has to be done to segregate the existing
single circuit into two circuits.
Pending
Overflux protection to be provided for 100 MVA, 230/ 110 kV ICT-1 & ICT-2.
Steps to be taken to ensure that Group-A & Group-B protections or Main & back-up protections of ICT's are fed from different DC
supplies.
Directionality to be provided for O/C protection of 100 MVA, 230/ 110 kV ICT-1 & ICT-2.
Directional E/F protection to be provided for 100 MVA, 230/ 110 kV ICT-1 & ICT-2.
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Page 42 of 70
Sl. No. Bay name/Bus Voltage Protection/Element/
Equipment/ System
auditated
Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
17 Mail dated 30.01.2018:
Various possible ways to connect the 110/22KV Villianur Sub-
Station with nearby 110/22KV Korkadu SS by 22KV feeder is
being explored.
Mail dated 13.03.2018:
Division-EHV of this department has been requested vide Lr.
No.714/Ed/EE-Auto SS/AEE-M-VASS/F-4/2017-18, dated
27.02.2018 (Copy enclosed) to explore the possibilities of
providing another 200KVA, 22KV/440V station transformer I
nearby 110/22KV Villianur SS that is charged by a 22KV feeder
either from 110/22KV Korkadu SS or Kurumbapet SS for
providing AC auxiliary supply to 230KV Villianur Auto SS.
Pending
18 Mail dated 30.01.2018 & 13.03.2018:
Existing Control & Relay Panels installed with static relays are
proposed to be replaced with new control panels installed with
numerical relays under the project of Upgradation of existing
static relays and replacement of sub-station equipments at
230KV Villianur and Bahour Auto Sub-Station at the cost of
Rs.10,56,16,191/- through PSDF funding. Tendering process for
award of work on labour contract basis for the above said work
is almost over and waiting for the approval of Puducherry
Government to place order at the lowest tenderer.
Pending
19 Mail dated 30.01.2018 & 13.03.2018:
Existing Control & Relay Panels installed with static relays are
proposed to be replaced with new control panels installed with
numerical relays under the project of Upgradation of existing
static relays and replacement of sub-station equipments at
230KV Villianur and Bahour Auto Sub-Station at the cost of
Rs.10,56,16,191/- through PSDF funding. Tendering process for
award of work on labour contract basis for the above said work
is almost over and waiting for the approval of Puducherry
Government to place order at the lowest tenderer.
Pending
20 Mail dated 30.01.2018 & 13.03.2018:
Existing Control & Relay Panels installed with static relays are
proposed to be replaced with new control panels installed with
numerical relays under the project of Upgradation of existing
static relays and replacement of sub-station equipments at
230KV Villianur and Bahour Auto Sub-Station at the cost of
Rs.10,56,16,191/- through PSDF funding. Tendering process for
award of work on labour contract basis for the above said work
is almost over and waiting for the approval of Puducherry
Government to place order at the lowest tenderer.
Pending
At present AC auxiliary supply is being provided from 440 Volt, 3phase, 50 Hz LT supply from 200 kVA, 22 kV/440 V Transformer
connected directly on the main bus of the nearby 110/22 kV Villianur SS. Since this substation is fed from 230/ 110 kV Villianur
substation, steps may be taken to provide redundant AC auxiliary supply by providing another 200 kVA, 22 kV/ 440 V transformer
in the 110/ 22 kV SS that is charged from 22 kV Korkadu feeder, and laying another 440 V cable from its secondary to thr AC
supply changeover panel at 230/ 110 kV Villianur SS.
GPS based time-synchronization equipment may be provided for synchronizing various 230 kV & 110 kV protection relays.
Steps may be to taken provide DR's with facility for automatic fault record downloading to a central PC/ server.
Standalone Event Logger may be provided.
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Annexure-VI
Page 43 of 70
Sl. No. Bay name/Bus Voltage Protection/Element/
Equipment/ System
auditated
Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
21 Mail dated 30.01.2018 & 13.03.2018:
As per the recommendation of Protection Audit Team, a Detailed
Project Report at the cost of Rs.14,85,42,653.21 has been
prepared to replace the existing aged equipments and provide
additional equipments at 230KV Villianur and Bahour Auto Sub-
Station and sent to higher authority to obtain sanction under
PSDF funding. (copy enclosed)
Pending
22 Mail dated 30.01.2018 & 13.03.2018:
As per the recommendation of Protection Audit Team, a Detailed
Project Report at the cost of Rs.14,85,42,653.21 has been
prepared to replace the existing aged equipments and provide
additional equipments at 230KV Villianur and Bahour Auto Sub-
Station and sent to higher authority to obtain sanction under
PSDF funding. (copy enclosed). In that DPR, replacement of
existing deteriorated RCC supporting structures have been
proposed to be replaced with G.I. lattice structure.
Pending
23 Mail dated 30.01.2018:
As per the recommendation of Protection Audit Team, a Detailed
Project Report at the cost of Rs.14,85,42,653.21 has been
prepared to replace the existing aged equipments and provide
additional equipments at 230KV Villianur and Bahour Auto Sub-
Station and sent to higher authority to obtain sanction under
PSDF funding. (copy enclosed). In that DPR, provision has been
given to provide chemically treated PCC flooring, and then
covering it with suitable blue metal spreading in switchyard area.
Mail dated 13.03.2018:
Vegetation & weeds grown in the switch yard area were
manually cleared and now the switch yard is kept clean.
However, as a permanent measure, Detailed Project Report at
the cost of Rs.14,85,42,653.21 has been prepared to replace the
existing aged equipments and provide additional equipments at
230KV Villianur and Bahour Auto Sub-Station and sent to higher
authority to obtain sanction under PSDF funding. (copy
enclosed). In that DPR, provision has been given to provide
chemically treated PCC flooring, and then covering it with
suitable blue metal spreading in switchyard area.
Pending
It was observed that existing 100 MVA transformers had not been provided with fire protection. Steps may be taken to provide the
same in accordance with the relevant standards.
It was observed that supporting structures and equipment such as breakers, CT's, isolators, etc. In 110 kV switchyard had served
thier full life. Steps may be taken to refurbishing of 110 kV switchyard appropriately.
Vegetation & weeding was observed in switchyard area. Steps may be taken to provide chemically treated PCC flooring, and then
covering it with suitable blue metal spreading in switchyard area.
44/70
Annexure-VI
Page 44 of 70
Sl. No. Bay name/Bus Voltage Protection/Element/
Equipment/ System
auditated
Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
24 Mail dated 30.01.2018 & 13.03.2018:
As per the recommendation of Protection Audit Team, a Detailed
Project Report at the cost of Rs.14,85,42,653.21 has been
prepared to replace the existing aged equipments and provide
additional equipments at 230KV Villianur and Bahour Auto Sub-
Station and sent to higher authority to obtain sanction under
PSDF funding. (copy enclosed). In that DPR, provision has been
given to replace the existing dilapidated gantry & equipment
supporting (RCC) structures with G.I. lattice / tubular
structures.
Pending
25 Mail dated 30.01.2018 & 13.03.2018:
Action has been initiated to bring down the earth resistance
value to less than 1ohm
Pending
26 Mail dated 30.01.2018:
Action has been initiated to Equipment labeling for proper phase-
sequence
Mail dated 13.03.2018:
The work of Equipment labeling for proper phase-sequence was
completed on 13.03.2018.
complied
27 Mail dated 30.01.2018:
Action has been initiated for Earthing of equipment including
door-to-panel earthing.
Mail dated 13.03.2018:
The work of Earthing of various equipment including door-to-
panel earthing was completed on 13.03.2018.
Complied
28 Mail dated 30.01.2018 & 13.03.2018:
Suitable canopy has been fabricated and kept on hand awaiting
for shutdown to provide over Buchholz relays
Pending
29 Mail dated 30.01.2018 & 13.03.2018:
Steps have been initiated to establish Standard Testing Lab and
procurement of essential testing equipments to cater to all 230
kV substations.
Pending
Equipment labeling for proper phase-sequence may be provided.
Earthing of various equipment including door-to-panel earthing to be properly ensured.
Buccholtz relays may be provided with suitable canopy to prevent unwarranted trippings due to moisture ingress.
At present, PED is dependent on external agencies for carrying out testing of various electrical equipment & relays & protection
oriented trouble shooting. Steps may be taken to establish Standard Testing Lab and procurement of essential testing equipments
to cater to all 230 kV substations under its control.
It was observed that most of the existing gantry & equipment supporting (RCC) structures are in dilapidated state. Steps may be
taken to replace them with suitable lattice/ tubular structures.
Earth-resistance values for various earth-pits seem to be on higher side. Steps may be taken to bring it down to less than 1 ohm.
45/70
Annexure-VI
Page 45 of 70
Sl. No. Bay name/Bus Voltage Protection/Element/
Equipment/ System
auditated
Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
30 Mail dated 30.01.2018:
Detailed scope of the works included in proposed R & U works
has already been furnished vide Lr.256/ED/EE-MRT&MMC/F-
SRPC/2017-18, dated 14.08.2017. (copy enclosed)
Mail dated 13.03.2018:
Detailed scope of the works included in proposed R & U works
has already been furnished vide Lr.256/ED/EE-MRT&MMC/F-
SRPC/2017-18, dated 14.08.2017. (copy enclosed
Complied
31 Mail dated 30.01.2018 & 13.03.2018:
Protection & Communication wing of TAN TRANSCO Limited,
Villupuram has been requested vide Lr. No.347/ED/EE-Auto
SS/AEE-M-VASS/F-4/2017-18, dated 21.09.2017 for revision of
existing relay settings as per the recommendations of Protection
Audit Team.
Pending
Sl. No. Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
1 Mail dated 30.01.2018 & 13.03.2018:
Existing Control & Relay Panels installed with static relays are
proposed to be replaced with new control panels installed with
numerical relays under the project of Upgradation of existing
static relays and replacement of sub-station equipments at
230KV Villianur and Bahour Auto Sub-Station at the cost of
Rs.10,56,16,191/- through PSDF funding. Tendering process for
award of work on labour contract basis for the above said work
is almost over and waiting for the approval of Puducherry
Government to place order at the lowest tenderer.
Pending
2 Mail dated 30.01.2018 & 13.03.2018:
Control & Relay Panels installed with static relays are proposed
to be replaced with new control panels installed with numerical
relays under the project of Upgradation of existing static relays
and replacement of sub-station equipments at 230KV Villianur
and Bahour Auto Sub-Station at the cost of Rs.10,56,16,191/-
through PSDF funding. Tendering process for award of work on
labour contract basis for the above said work is almost over and
waiting for the approval of Puducherry Government to place
order at the lowest tenderer.
Pending
In view of radial operation of 110 kV feeders, Zone-1 reach may be increased to 90 % of line length, and Zone-2 time-setting may
be reduced to 150 msec.
2) 230/ 110 kV Bahour SS [10 - 12 July, 2017]
Deficiences/Nonconformity observed
It is observed that main protections of feeders (230 kV as well as 110 kV) and trasformers are being provided from static relays.
Steps may be taken to replace the same with suitable numerical relays.
PED informed that they had already initiated steps for Renovation & Upgradation (R&U) of grid stations in Pondycherry region
(230/ 110 kV Villianur SS & 230/ 110 kV Bahour SS) under PSDF funding, covering most of the above works. In this regard, PED is
requested to furnish detailed scope of the works included in proposed R & U works.
Directional O/C & E/F protections to be provided for 230 kV & 110 kV feeders where Main-II is not provided; Directional E/F
protection to be provided for 230 kV & 110 kV feedes where Main-I & Main-II are provided
46/70
Annexure-VI
Page 46 of 70
Sl. No. Bay name/Bus Voltage Protection/Element/
Equipment/ System
auditated
Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
3 Mail dated 30.01.2018 & 13.03.2018:
Protection & Communication wing of TAN TRANSCO Limited,
Villupuram has been requested vide Lr. No.347/ED/EE-Auto
SS/AEE-M-VASS/F-4/2017-18, dated 21.09.2017 for revision of
existing relay settings as per the recommendations of Protection
Audit Team.
Pending
4 Mail dated 30.01.2018 & 13.03.2018:
Protection & Communication wing of TAN TRANSCO Limited,
Villupuram has been requested vide Lr. No.347/ED/EE-Auto
SS/AEE-M-VASS/F-4/2017-18, dated 21.09.2017 for revision of
existing relay settings as per the recommendations of Protection
Audit Team.
Pending
5 Mail dated 30.01.2018 & 13.03.2018:
Protection & Communication wing of TAN TRANSCO Limited,
Villupuram has been requested vide Lr. No.347/ED/EE-Auto
SS/AEE-M-VASS/F-4/2017-18, dated 21.09.2017 for revision of
existing relay settings as per the recommendations of Protection
Audit Team.
Pending
6 Mail dated 30.01.2018 & 13.03.2018:
Protection & Communication wing of TAN TRANSCO Limited,
Villupuram has been requested vide Lr. No.347/ED/EE-Auto
SS/AEE-M-VASS/F-4/2017-18, dated 21.09.2017 for revision of
existing relay settings as per the recommendations of Protection
Audit Team.
Pending
7 Mail dated 30.01.2018 & 13.03.2018:
Protection & Communication wing of TAN TRANSCO Limited,
Villupuram has been requested vide Lr. No.347/ED/EE-Auto
SS/AEE-M-VASS/F-4/2017-18, dated 21.09.2017 for revision of
existing relay settings as per the recommendations of Protection
Audit Team.
Pending
8 Mail dated 30.01.2018 & 13-03-2018:
Co-ordination of Protection & Communication wing of TAN
TRANSCO Limited, Villupuram has been requested to bring the
230KV and 110KV Bus Bar Protection scheme into service.
Pending
Load encroachment feature may be appropriately kept enabled in 230 kV & 110 kV feeders.
It is observed that busbar protection relays have been provided for both 230 kV & 110 kV buses. However, the same have been
kept out of service since commisssioning. PED shall take steps to put these into operation.
Z4 (reverse) is to be provided in all distance relays of 230 kV & 110 kV feeders
Z2 and Z3 (reactive & resistive) reaches & time settings were observed to be not in line with Ramakrishna Committee guidelines,
which may be reviewed appropriately.
Auto-reclosure dead-time and reclaim-time for 230 kV feeders may be revised to 1 sec and 25 sec respectively. Accordingly Pole
Discreancy time-delay may be kept at 1.5 sec.
Power Swing Philosophy (Z1 --> Unblock; Higher Zones --> Block for 2 sec) is to be adoped unfiromly across all 230 kV feeders.
47/70
Annexure-VI
Page 47 of 70
Sl. No. Bay name/Bus Voltage Protection/Element/
Equipment/ System
auditated
Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
9 Mail dated 30.01.2018 & 13.03.2018:
Protection & Communication wing of TAN TRANSCO Limited,
Villupuram has been requested vide Lr. No.347/ED/EE-Auto
SS/AEE-M-VASS/F-4/2017-18, dated 21.09.2017 for revision of
existing relay settings as per the recommendations of Protection
Audit Team.
Pending
10 Mail dated 30.01.2018 & 13.03.2018:
One set of existing aged 110Volt Station Battery has been
replaced with a new battery bank during the last week of
January 2018. Action has been initiated for necessary wiring to
segregate Main-I and Main-II Protection to fed from different DC
source.
Pending
11 Mail dated 30.01.2018 & 13.03.2018:
Existing Control & Relay Panels installed with static relays are
proposed to be replaced with new control panels installed with
numerical relays under the project of Upgradation of existing
static relays and replacement of sub-station equipments at
230KV Villianur and Bahour Auto Sub-Station at the cost of
Rs.10,56,16,191/- through PSDF funding. Tendering process for
award of work on labour contract basis for the above said work
is almost over and waiting for the approval of Puducherry
Government to place order at the lowest tenderer.
Pending
12 Mail dated 30.01.2018 & 13.03.2018:
Existing Control & Relay Panels installed with static relays are
proposed to be replaced with new control panels installed with
numerical relays under the project of Upgradation of existing
static relays and replacement of sub-station equipments at
230KV Villianur and Bahour Auto Sub-Station at the cost of
Rs.10,56,16,191/- through PSDF funding. Tendering process for
award of work on labour contract basis for the above said work
is almost over and waiting for the approval of Puducherry
Government to place order at the lowest tenderer.
Pending
For 230 kV Pondy feeder POR may be used in place of the existing PUR.
Steps to be taken to ensure that Main-I & Main-II protections or Main & back-up protections of feeders are fed from different DC
supplies.
REF protection to be provided for 80 MVA, 230/ 110 kV Transformers -1 & 2.
Directionality to be provided for O/C protection of 80 MVA, 230/ 110 kV Transformers -1 & 2.
48/70
Annexure-VI
Page 48 of 70
Sl. No. Bay name/Bus Voltage Protection/Element/
Equipment/ System
auditated
Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
13 Mail dated 30.01.2018 & 13.03.2018:
Existing Control & Relay Panels installed with static relays are
proposed to be replaced with new control panels installed with
numerical relays under the project of Upgradation of existing
static relays and replacement of sub-station equipments at
230KV Villianur and Bahour Auto Sub-Station at the cost of
Rs.10,56,16,191/- through PSDF funding. Tendering process for
award of work on labour contract basis for the above said work
is almost over and waiting for the approval of Puducherry
Government to place order at the lowest tenderer.
Pending
14 Mail dated 30.01.2018 & 13.03.2018:
Existing Control & Relay Panels installed with static relays are
proposed to be replaced with new control panels installed with
numerical relays under the project of Upgradation of existing
static relays and replacement of sub-station equipments at
230KV Villianur and Bahour Auto Sub-Station at the cost of
Rs.10,56,16,191/- through PSDF funding. Tendering process for
award of work on labour contract basis for the above said work
is almost over and waiting for the approval of Puducherry
Government to place order at the lowest tenderer.
Pending
15 Mail dated 30.01.2018 & 13.03.2018:
One set of existing aged 110Volt Station Battery has been
replaced with a new battery bank during the last week of
January 2018. Action has been initiated for necessary wiring to
segregate Group-A and Group-B Protection of Transformer fed
from different DC source.
Pending
16 Mail dated 30.01.2018 & 13.03.2018:
Existing Control & Relay Panels installed with static relays are
proposed to be replaced with new control panels installed with
numerical relays under the project of Upgradation of existing
static relays and replacement of sub-station equipments at
230KV Villianur and Bahour Auto Sub-Station at the cost of
Rs.10,56,16,191/- through PSDF funding. Tendering process for
award of work on labour contract basis for the above said work
is almost over and waiting for the approval of Puducherry
Government to place order at the lowest tenderer.
Pending
Directional E/F protection to be provided for 80 MVA, 230/ 110 kV Transformers -1 & 2.
Overflux protection to be provided for 80 MVA, 230/ 110 kV Transformers -1 & 2.
Steps to be taken to ensure that Group-A & Group-B protections or Main & back-up protections of Transformers are fed from
different DC supplies.
GPS based time-synchronization equipment may be provided for time-synchronizing various 230 kV & 110 kV protection relays.
49/70
Annexure-VI
Page 49 of 70
Sl. No. Bay name/Bus Voltage Protection/Element/
Equipment/ System
auditated
Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
17 Mail dated 30.01.2018 & 13.03.2018:
Existing Control & Relay Panels installed with static relays are
proposed to be replaced with new control panels installed with
numerical relays under the project of Upgradation of existing
static relays and replacement of sub-station equipments at
230KV Villianur and Bahour Auto Sub-Station at the cost of
Rs.10,56,16,191/- through PSDF funding. Tendering process for
award of work on labour contract basis for the above said work
is almost over and waiting for the approval of Puducherry
Government to place order at the lowest tenderer.
Pending
18 Mail dated 30.01.2018 & 13.03.2018:
Existing Control & Relay Panels installed with static relays are
proposed to be replaced with new control panels installed with
numerical relays under the project of Upgradation of existing
static relays and replacement of sub-station equipments at
230KV Villianur and Bahour Auto Sub-Station at the cost of
Rs.10,56,16,191/- through PSDF funding. Tendering process for
award of work on labour contract basis for the above said work
is almost over and waiting for the approval of Puducherry
Government to place order at the lowest tenderer.
Pending
19 Mail dated 30.01.2018 & 13.03.2018:
As per the recommendation of Protection Audit Team, a Detailed
Project Report at the cost of Rs.14,85,42,653.21 has been
prepared to replace the existing aged equipments and provide
additional equipments at 230KV Villianur and Bahour Auto Sub-
Station and sent to higher authority to obtain sanction under
PSDF funding. (copy enclosed). In that DPR, provision has been
given to provide Line CVTs in all phases for all 230KV Lines..
Pending
20 Mail dated 30.01.2018 & 13.03.2018:
As per the recommendation of Protection Audit Team, a Detailed
Project Report at the cost of Rs.14,85,42,653.21 has been
prepared to replace the existing aged equipments and provide
additional equipments at 230KV Villianur and Bahour Auto Sub-
Station and sent to higher authority to obtain sanction under
PSDF funding. (copy enclosed). In that DPR, provision has been
given to provide Surge Arrestors for 230KV feeders at gantry
entry point.
Pending
Steps may be to taken provide DR's with facility for automatic fault record downloading to a central PC/ server.
Stand-alone Event Logger may be provided.
Line CVT's to be provided in all phases for all 230 kV lines.
Surge Arrestors to be to be provided for 230 kV feeders at gantry entry point.
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Page 50 of 70
Sl. No. Bay name/Bus Voltage Protection/Element/
Equipment/ System
auditated
Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
21 Mail dated 30.01.2018 & 13.03.2018:
Budgetary offer has been called for from a reputed contractor
for arresting oil leakage observed in the Transformers. Work will
be commenced shortly on obtaining expenditure sanction from
the competent authority on the estimate prepared with the rate
offered by the contractor.
Pending
22 Mail dated 30.01.2018 & 13-03-2018:
the recommendation of Protection Audit Team, a Detailed
Project Report at the cost of Rs.14,85,42,653.21 has been
prepared to replace the existing aged equipments and provide
additional equipments at 230KV Villianur and Bahour Auto Sub-
Station and sent to higher authority to obtain sanction under
PSDF funding. (copy enclosed). In that DPR, provision has been
given to provide fire protection system to 80MVA Auto
Transformer-I&II.
Pending
23 Mail dated 30.01.2018 & 13.03.2018:
OEM M/s.Crompton Greaves Limited has been requested to offer
rate to bring back the 230KV Bus Coupler Breaker into service.
As per the recommendation of Protection Audit Team, a Detailed
Project Report at the cost of Rs.14,85,42,653.21 has been
prepared to replace the existing aged equipments and provide
additional equipments at 230KV Villianur and Bahour Auto Sub-
Station and sent to higher authority to obtain sanction under
PSDF funding. (copy enclosed). In that DPR, provision has been
given to provide attendant CTs to make way to two-zone busbar
protection.
Pending
24 Mail dated 30.01.2018 & 13.03.2018:
Action has been initiated to segregate the wiring for extending
supply from DC1 and DC2 to trip coil of 230KV and 110KV
Breakers.
Pending
25 Mail dated 30.01.2018:
In addition to the existing 48Volt PLCC battery, one more 48Volt
PLCC Battery bank has been erected and commissioned during
the last week of January 2018. Wiring will be done to segregate
Source-1 & II.
Mail dated 30.01.2018 & 13-03-2018:
In addition to the existing 48Volt PLCC battery, one more 48Volt
PLCC Battery bank has been erected and commissioned as a
redundant DC supply for communication during the last week of
January 2018 with requisite segregation in wiring.
Complied
Oil leakage is being observed in both 80 MVA, 230/ 110 kV Tranformers. Suitable action may be taken to arrest the same.
It is observed that existing 80 MVA transformers have not been provided with fire protection. Steps may be taken to provide the
same in accordance with relevant standards.
It is observed that 230 kV & 110 kV Bus-Coupler breakers are not in working condition, and have been kept out of service. Also
they have no attendant CT's. PED may therefore take steps to replace them with attendant CT's to make way for two-zone busbar
protection.
Segregation in wiring for extending supply from DC1 and DC2 to trip coils of 230 kV & 110 kV feeders to be carried out.
Redundant DC suppy for communication (48 V) application to be provided with requisite segregation in wiring.
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Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
26 Mail dated 30.01.2018 & 13.03.2018:
Action has been initiated to earth all gantry towers (metallic
structures) including lightning mast.
Pending
27 Mail dated 30.01.2018:
Action has been initiated to Equipment labeling for proper phase-
sequence
Mail dated 13.04.2018:
The work of Equipment labeling for proper phase-sequence was
completed on 13.03.2018.
complied
28 Mail dated 30.01.2018:
Action has been initiated for Earthing of equipment including
door-to-panel earthing.
Mail dated 13.04.2018:
The work of Door-to-panel earthing in various switchyard
marshalling panels was completed on 13.03.2018.
complied
29 Mail dated 30.01.2018 & 13.03.2018:
Suitable canopy has been fabricated and kept on hand awaiting
for shutdown to provide over Buchholz relays
Pending
30 Mail dated 30.01.2018:
Exploring all the possible ways to provide another dedicated
redundant AC auxiliary supply from nearby 110/22KV Sub-
Station which is being fed by other 230KV Sub-Stations.
Mail dated 13.04.2018:
Division-EHV of this department has been requested vide Lr.
No.714/Ed/EE-Auto SS/AEE-M-VASS/F-4/2017-18, dated
27.02.2018 (Copy enclosed) to explore the possibilities of
arranging an alternate 22KV supply fed from 110/22KV Sub-
Stations those are either fed from 230KV Villianur Auto SS or
230KV Thondamanatham Auto SS for the existing 22KV/440V
Distribution Transformer installed in the campus of 230KV
Bahour Auto SS, presently being fed by 22KV Pandasozhannlur
feeder from 110/22KV Bahour SS.
Pending
31 Mail dated 30.01.2018 & 13.03.2018:
DC earth leakage being observed in the battery charger will be
attended in the forthcoming total shutdown. Replacement of
existing DC Distribution Panels have been included in the DPR.
Pending
Equipment labeling for proper phase-sequence may be provided.
Door-to-panel earthing in various switchyard marshalling panels to be properly ensured.
Buccholtz relays may be provided with suitable canopy to prevent unwarranted trippings due to moisture ingress.
At present AC auxiliary supply is being obtained from 22 kV Bahour (Pandasozhanallur) feeder from nearby 110/ 22 kV Bahour SS.
Since this 110/ 22 kV SS is being fed from the present 230/ 110 kV SS, in the event of supply failure at the latter, the former will
also lose supply. PED shall take steps to provide another dedicated redundant AC auxiliary supply feeder.
DC earth leakage is being observed in both 110 V DC Sources. Also the corresponding DC Earth-fault relays in soruce end DCDB
panels are observed to be not in working-condition. Steps shall be taken to rectify the same at the earliest.
All gantry towers (metallic structures) including lightning masts to be earthed properly as per relevant standards.
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Remarks Latest Status (To be filled up by the
Constituent)
32 Mail dated 30.01.2018:
As per the recommendation of Protection Audit Team, a Detailed
Project Report at the cost of Rs.14,85,42,653.21 has been
prepared to replace the existing aged equipments and provide
additional equipments at 230KV Villianur and Bahour Auto Sub-
Station and sent to higher authority to obtain sanction under
PSDF funding. (copy enclosed). In that DPR, provision has been
given to provide chemically treated PCC flooring, and then
covering it with suitable blue metal spreading in switchyard area.
Mail dated 13.04.2018:
Vegetation & weeds grown in the switch yard area were
manually cleared and now the switch yard is kept clean.
However, as a permanent measure, Detailed Project Report at
the cost of Rs.14,85,42,653.21 has been prepared to replace the
existing aged equipments and provide additional equipments at
230KV Villianur and Bahour Auto Sub-Station and sent to higher
authority to obtain sanction under PSDF funding. (copy
enclosed). In that DPR, provision has been given to provide
chemically treated PCC flooring, and then covering it with
suitable blue metal spreading in switchyard area.
Pending
33 Mail dated 30.01.2018 & 13.03.2018:
As per the recommendation of Protection Audit Team, a Detailed
Project Report at the cost of Rs.14,85,42,653.21 has been
prepared to replace the existing aged equipments and provide
additional equipments at 230KV Villianur and Bahour Auto Sub-
Station and sent to higher authority to obtain sanction under
PSDF funding. (copy enclosed). In that DPR, provision has been
given to replace the existing dilapidated gantry & equipment
supporting (RCC) structures with G.I. lattice / tubular
structures.
Pending
34 Mail dated 30.01.2018 & 13.03.2018:
Actions have been initiated for Testing of various relays and
measurement of earth-resistance values for various earth-pits
periodically as per relevant standards and record them properly
Pending
35 Mail dated 30.01.2018 & 13.03.2018:
Protection and Communication wing of TAN TRANSCO Limited,
Villupuram has been requested to furnish the existing relay
settings for future reference.
Pending
Vegetation & weeding is observed in switchyard area. Steps may be taken to provide chemically treated PCC flooring, and then
covering it with suitable blue metal spreading in switchyard area.
It is observed that most of the existing gantry & equipment supporting structures have been of RCC. PED may take steps to
replace them with suitable lattice/ tubular structures when R & M works for the substation are propsoed.
Testing of various relays and measurement of earth-resistance values for various earth-pits should be undertaken periodically as
per relevsnt standards, and records properly maintained.
It is observed that relay settings for various protection relays have been set by TNEB at the time of commissioning. However,
records relating to the same have not been made available to PED. Steps may be taken (by PED/ TNEB) to maintain proper
records w.r.t. Implemented relay settings at Substation level.
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Remarks Latest Status (To be filled up by the
Constituent)
36 Mail dated 30.01.2018 & 13.03.2018:
Steps have been initiated to establish Standard Testing Lab and
procurement of essential testing equipments to cater to all 230
kV substations.
Pending
37 Mail dated 30.01.2018:
Detailed scope of the works included in proposed R & U works
has already been furnished vide Lr.256/ED/EE-MRT&MMC/F-
SRPC/2017-18, dated 14.08.2017. (copy enclosed)
Mail dated 13.04.2018:
Detailed scope of the works included in proposed R & U works
has already been furnished vide Lr.256/ED/EE-MRT&MMC/F-
SRPC/2017-18, dated 14.08.2017. (copy enclosed)
Complied
Mail dated 30.01.2018 & 13.03.2018:
Fault level of the station has been requested from EHV division
of this department. Details will be furnished as soon as received
from the said division.
Mail dated 30.01.2018 & 13.03.2018:
Protection and Communication wing of TAN TRANSCO Limited,
Villupuram has been requested to furnish the existing relay
settings. Relay settings will be furnished as soon as received
from the said corporation.
Mail dated 30.01.2018 & 13.03.2018:
Details are being collected from the source available at 230KV
Bahour Auto Sub-Station. Details will be furnished shortly.
Mail dated 30.01.2018 & 13.03.2018:
Action has been initiated to measure the Earth-mats and Earth-
Pits value. Measurements will be submitted shortly.
Mail dated 30.01.2018 & 13.03.2018:
Will be submitted shortly.
Mail dated 30.01.2018:
Details have been called for from TAN TRANSCO Limited. Will be
submitted shortly on receipt of the same.
PED informed that they had already initiated steps for Renovation & Upgradation (R&U) of grid stations in Pondycherry region
(230/ 110 kV Villianur SS & 230/ 110 kV Bahour SS) under PSDF funding, covering relay & control panel replacement works. In this
regard, PED is requested to furnish detailed scope of the works included in proposed R & U works for the 230/ 110 kV substation.
PED has not provided the following data as part of protection audit:
(i) Fault level of the Substation for 3-ph-Ground and 1-ph-Ground faults at both 230 kV and 110 kV levels
(ii) Adopted Relay Settings (given by Head Quarters/ Corporate Office and implemented in field)
(iii) Details on Periodicity of Relay Testing and latest Relay Test Reports
At present, PED is dependent on external agencies for carrying out testing of various electrical equipment & relays & protection
oriented trouble shooting. Steps may be taken to establish Standard Testing Lab and procurement of essential testing equipments
to cater to all 230 kV substations under its control.
(iv) Details of Measurement of Station Earth-Mat & Earth-Pits
(v) AC Supply Changeover Scheme
(vi) Details of 110 kV CT's Ratios and Errors
PGCIL (SR-I)
1) 400 kV & HVDC Gajuwaka SS [28-30 December, 2015]
38 Pending
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Remarks Latest Status (To be filled up by the
Constituent)
Sl. No. Bay name/Bus Voltage Protection/Element/
Equipment/
System auditated
Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
1 General In pole 1 Trip Circuit Supervision relays are not available in the circuit.
However Trip Circuit Supervision is being monitored by RPC (Reactive
Power Control)
Mail Dated 05-02-2018:
Pole-1 RPC system trip circuit supervision relays are installed in
the month Dec-2017 & presently in service.
Complied
2 General HVDC pole - 1 & 2 Auxiliaries supply (33 kV) are being fed from ICT-2
(tertiary) only. In the event of failure of auxiliary supply DG set 1 & 2
respectively will feed the supply to the Auxiliaries.
Mail Dated 05-02-2018:
Aux supply provision from ICT-1 (Second Aux supply)
comissioned. Automatic supply changeover scheme for Pole-1
has implemented. In the event of failure of auxiliary supply DG
set feed the supply to the auxiliries.
Order placed for retrofitting of LT brakers in Auxiliary system &
installation will complete by 30-April-2018.
Complied
3 General HVAC S/S Auxiliaries supply (33 kV) are being fed from APTRANSCO
feeder only. In the event of failure of auxiliary supply DG set will feed the
supply to the Auxiliaries.
Mail Dated 05-02-2018:
Presently HVAC S/S Auxiliaries supply (33 kV) are feeding from
APTRANSCO feeder only. In the event of failure of auxiliary
supply DG set is feeding the supply to the Auxiliaries.
Pending
4 General HVAC DG set starting by manual only. Mail Dated 05-02-2018:
HVAC DG set is presently starting by manual in case of supply
failure. The same shall be changed to auto & will completed in
NTAMC sworks by October-2018.
Pending
5 General Oil leakage was observed from the line reactor of Vijayawada line Mail Dated 05-02-2018:
Oil leakages of Vijayawada L/R rectified in the month of April-
2016.
Complied
6 General Stub Protection time delay is kept as 100 ms. Mail Dated 05-02-2018:
As per POWERGRID, Corporate recommendations Stub prot
settings are adopted as 2.0 A ( Sec) if CT ratio is <=1000A & &
time delay 100 msec. For others 1.5 Amp.
Pending
7 General For 400 kV Kalpakka Line-1, Circuit Breaker Pole discrepancies kept as
1.0 s
Mail Dated 05-02-2018:
400 kV Kalpakka Line-1, Circuit Breaker Pole discrepancies
changed to 2.5 sec from 1.0 sec in Janaury-2016.
Complied
8 General For 400kV Kalpakka line 1& line 2,
Main- 1 relay:
Reverse Zone is not available in REL-100.
Zone- 3 time delay is observed as 1.5 sec.
Stand alone Auto reclosure in off condition.
Relay is not time synchronized with GPS.
Main- 2 relay:
Reverse Zone setting time kept as 2s.
Over Current protection enabled.
DEF is not provided.
Stand alone Auto reclosure in off condition.
Relay is not time synchronized with GPS.
Mail Dated 05-02-2018:
Informed to APTRANSCO for necessary action & 400kV
Gazuwaka-Kalpaka-1&2 line settings modified as per
Ramakrishna Committee recommendations in December-2017.
However the same relays will be retrifitted with LDP relays by
APTRANSCO. In 71st PCSC meeting APTRANSCO informed that
the LDP relay installation will complete by April-2018.
Pending
2) 400/ 220 kV Gooty SS [12th, 13th and 15th February, 2016]
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Remarks Latest Status (To be filled up by the
Constituent)
Sl. No. Bay name/Bus Voltage Protection/Element/
Equipment/ System
auditated
Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
1 400kV Control and
Protection Panels
For 400 KV Busbar protection (RADSS of ABB make), one main Bus bar
protection scheme for each Bus 1 & Bus 2 available and Check Zone
protection is not available . Redundant Bus bar protection or Check zone
shall be considerd.
Mail Dated 05-02-2018:
In place of Main & Check Zone , In ABB make RADSS B/B
protection relay Start & Differential features are available.
IN RSTPP, CTP-1 Transmission systems Bus Bar protection
scheme was envisaged as per CEA/CBIP guidelines then
existing.
Retrofitting of existing B/B schme with redundant BB
protection shall be proposed under ADD CAP.
Pending
2 DEF protection is enabled in Main-1 of 400kV Nelamangala & Kurnool AP
line. However inspite of availability of DEF protection in Main 2 (Ohmega)
Distance relays is not enabled. Powergrid informed that settings adopted
for Ohmega relay is as per CC Recommendation
Mail Dated 05-02-2018:
We have observed mal-operation of DEF protection in Omegha
relays & hence the DEF feature disabled.
Proposal for retrofitting of Omegha relay with latest numerical
relay has been approved and is under tendering stage. The
same shall be retrofitted by October-2018.
Pending
3 Kurnool PG Line reactor and Bus reactor RWTI meters placed in control
panel are not in working condition.
Mail Dated 05-02-2018:
Rectified & faulty meters were replaced with new meters On 05-
05-2017
Complied
4 Stub protection current set and time delay set as I> 150% and 100ms
against the recommendeed setting of I>250% and time delay of 50ms by
M/S Tractebel.Powergrid informed that settings adopted as per CC
Recommendation
Mail Dated 05-02-2018:
As per POWERGRID, Corporate recommendations Stub prot
settings are adopted as 2.0 A ( Sec) if CT ratio is <=1000A & &
time delay 100 msec. For others 1.5 Amp.
Pending
5 AC Distribution It was observed that one 33kV feeder is available for auxilliary supply of
station. POWERGRID informed that second redundant AC supply source
from ICT-II tertiary winding is under progress.
Mail Dated 05-02-2018:
On 29-05-2016 second redundant AC supply source from ICT-II
tertiary winding is Charged.
Complied
6 DC Distribution For 400kV bus bar protection panel, 2 DC sources are available with
selector switch only. Automatic changeover is not provided.
Mail Dated 05-02-2018:
IN RSTPP, CTP-1 Transmission systems Bus Bar protection
scheme was envisaged as per CEA/CBIP guidelines then
existing.
Retrofitting of existing B/B schme with redundant BB
protection shall be proposed under ADD CAP.
Pending
7 Battery voltage measured on the date of audit is as below:
P-N(v) P-E(v) N-E(v)
220V Battery set 1 : 225.5 98.2 -127.0
220V Battery set 2 : 233.3 96.8 -136.0
48V Battery set 1 : 53.6 NA 51.9
48V Battery set 2 : 52.4 NA 53.0
Mail Dated 05-02-2018:
Battery voltage measured on 03.02.2018 and is as below:
P-N(v) P-E(v) N-E(v)
220V Battery set 1 : 218.6 + 115.9 -102.5
220V Battery set 2 : 243.0 + 122.4 -120.4
48V Battery set 1 : 48.8 NA -48.5
48V Battery set 2 : 52.8 NA -52.4
Complied
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auditated
Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
8 400kV Switchyard Field
Equipments
Lightning protection ( LAs) Earthing is not done as per standards/ NFPA
for ICT-1 & 400kV Gooty-Kurnool PG Line Reactor. LAs (system ) earthing
are not connected to earth electrodes directly instead it is connected
through equipment earthing. It should be modified similar to other bays.
Mail Dated 05-02-2018:
LA Earthing was modified during AMP S/D of GOOTY-KNL PG
L/R On dt 27.06.2017 &
During AMP S/D of ICT-1 On dt 10.06.2017
Complied
Sl. No. Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
1 Letter Dated 19-AUG-2017:
The reaches/ Pickup/ Drop off of all the numerical relays are
being checked on 04 yearly basis as per powergrid preventive
maintenance procedures. However, DC logics, Trip Logics, Auto-
reclosure, O/V, Stub functions etc. are being tested/checked
during every AMPs and oppurtunity shutdowns.
Pending
2 Letter Dated 19-AUG-2017:
Implimented as per POWERGRID philosophy and Ramakrishna
Committee recommendations.
Pending
3 Letter Dated 19-AUG-2017:
Intentional Delay of 100 msec( with POR) provided for zone-1 of
Gooty-1 &2 feeders in view of FSC at Gooty substion.
Complied
4 Letter Dated 19-AUG-2017:
Measurement principle of each relays (different manufacturers)
for Phase- Earth Resistive reaches are different and hence the
resistive reaches (Phase-Earth) for REL670/P444/7SA522 Relays
kept different.
Complied
5 Complied
Sl. No. Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
1 Pending
2 Pending
4) 765/ 400 kV Maheshwaram (GIS) SS [8 - 9 February, 2018]
Deficiences/Nonconformity observed
Colour coding for phase identification of breakers may be provided in 765 kV & 400 kV GIS Halls.
For 400 kV Maheshwaram (PG) - Maheshwaram (TS) lines 1 & 2, presently Line Differential Protection (LDP) and Distance
Protection (DP) have been provided as Main-I and Main-II respectively. Since they are very short lines, steps shall be taken to
provide LDP as Main-II also.
As most of the numerical relays have completed 4-years of in-service operation, comprehensive testing of the same may be
carried out.
In addition to blocking of distance protection under VT fuse-fail conditions, it shall be ensured that upon detection of a fault
(sensed by negative sequence component), blocking of distance protection gives rise to operation of its inherent Over-Current
protection with a suitable definite time delay of (say) 500 msec.
It is observed that Zone-1 time delay for Gooty lines 1 & 2 is kept as 100 msec, which may be clarified/ reviewed.
Z2, Z3 and Z4 Resistive reaches for Ph-G faults for Main-I & Main 2 have been found to be kept differently on 400 kV NCC lines 1
& 2, 400 kV Gooty lines & 765 kV Kurnool lines, which may be reviewed.
PLCC dB level (signal strength) measurements are being done on yearly basis.
3) 765/ 400 kV Nellore PS [19 - 20 June, 2017]
Deficiences/Nonconformity observed
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Remarks Latest Status (To be filled up by the
Constituent)
3 Pending
4 Pending
In 765/ 400 kV ICTs - 1 & 2, it is noted that all Group-A protections containing the primary Differential and the secondary DOCE
(HV) have been provided from one relay. Similarly, all Group-B protections containing the primary REF and the secondary DOCE
(LV) have been provided from another relay. Since, there is no duplication of these group protections, steps shall be taken to
provide the primary and secondary protections of each group from different relays for better reliability.
Commissioning of Aux. Supply from ICT-2's Tertiary as redundant auxiliary supply may be expedited.
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Remarks Latest Status (To be filled up by the
Constituent)
5 Pending
6 Pending
7 Pending
Sl. No. Bay name/Bus Voltage Protection/Element/
Equipment/ System
auditated
Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
1 General Zone 3 and reverse zone resistive reach settings are differently seted in
the relays
Mail dated 30.01.2018:
The Zone 3 Settings kept as 1 Sec, in case it is crossing the next
voltage level the same was kept as 1.5Sec.
Complied
2 General Zone 4 reach should be set to cover 50% of shortest line connected in
Hosur SS ( existing settings are set to 20% of protected line)
Mail dated 30.01.2018:
Presently kept as 20% of Protected line.
Mail dated 13.02.2018:
Kept as 20% of Protected line which will cater the functional
requirement as per the organizational Philosophy.
Pending
3 General PSB for 400kv is in line with guide line the same is not respected on
230kv lines ( all zone are blocked)
Mail dated 30.01.2018:
For 220/230kV lines all zones are blocked for PSB.
Mail dated 13.02.2018:
For 220/230kV lines all zones are blocked for PSB as per the
organizational Philosophy.
Pending
4 General STUB should be set to 50ms ( existing settings are 100ms) Mail dated 30.01.2018:
Under Review
Mail dated 13.02.2018:
Kept as 100msec of Protected line which will cater the functional
requirement as per the organizational Philosophy. In case of
inadvertant initiation, the line might trip with a delay of 50ms for
even an outzone fault. 100ms is given to let the primary
protection of the downstream line operate.
Pending
In addition to blocking of distance protection under VT fuse-fail conditions, it shall be ensured that upon detection of a fault
(sensed by negative sequence component), blocking of distance protection gives rise to operation of its inherent Over-Current
protection with a suitable definite time delay of (say) 600 msec.
Stub Protection Timing, which is presently kept as 100 msec may be suitably revised to 50 msec.
Calculation Sheet(s) showing protection settings calculation for all feeders and transformers may be furnished.
PGCIL (SR-II)
1) 400 kV Hosur SS [9-11 December, 2015]
2) 400 kV Tirunelveli SS [8th, 9th and 11th January, 2016]
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Remarks Latest Status (To be filled up by the
Constituent)
Sl. No. Bay name/Bus Voltage Protection/Element/
Equipment/ System
auditated
Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
1 Zone 3 and reverse zone fault resistive reach settings are not matching
and different w.r.t. TE settings for all 400 and 230 KV feeders.
Mail dated 30.01.2018:
The Zone 3 Settings kept as 1 Sec, in case it is crossing the next
voltage level the same was kept as 1.5Sec
Complied
2 Zone3 time delay has been set as 1.5s instead of 1sec except Veeranam
line
Mail dated 30.01.2018:
The Zone 3 Settings kept as 1 Sec, in case it is crossing the next
voltage level the same was kept as 1.5Sec
Complied
3 Zone 4 reach setting should be set to cover 50% of shortest line
connected in Tirunelveli SS. The existing setting for Zone-4 is different for
all the 400kV & 220kV lines.
Mail dated 30.01.2018:
Presently kept as 20% of Protected line.
Mail dated 13.02.2018:
Kept as 20% of Protected line which will cater the functional
requirement as per the organizational Philosophy.
Pending
4 PSB: For 400kv, all zones except zone-1 are blocked. For 220kV all zones
are blocked.
Mail dated 30.01.2018:
For 220/230kV lines all zones are blocked for PSB.
Mail dated 13.02.2018:
For 220/230kV lines all zones are blocked for PSB as per the
organizational Philosophy.
Pending
5 STUB protection timing should be set to 50ms. Existing setting is 100ms
for 400kV Lines.
Mail dated 30.01.2018:
Under Review.
Mail dated 13.02.2018:
Kept as 100msec of Protected line which will cater the functional
requirement as per the organizational Philosophy. In case of
inadvertant initiation, the line might trip with a delay of 50ms for
even an outzone fault. 100ms is given to let the primary
protection of the downstream line operate.
Pending
6 In 400KV Madurai line setting Zone-2 time delay is kept 0.5 sec instead of
0.35sec
Mail dated 30.01.2018:
The time Descremenation depends on remote end lines co
ordination. Accordingly 0.5 was kept.
Complied
7 For 220kV lines dedicated speech available for Edamon DC lines only. Not
available for all other lines pertaining to TANTRANSCO (Udayathur,
Kayathar, Veeranam, Sanganeri)
Mail dated 30.01.2018:
All the 220kV PLCC panels except Edamaon belongs to
TANTRANSCO.
Pending
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auditated
Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
8 Following Protection & Data/speech channels used in 220kV Lines:
a) Edamon-1 line - 2protection+1data/speech
b) Edamon-2 line - 2protection; (Edamon 1&2 is DC Line)
c) Udayathur line - 1protection
d) Veeranam line - 1protection
e) Kayathar line - 1protection
f) Sanganeri line - 1protection
Mail dated 30.01.2018:
In line with Standard Philosophy for POWERGRID owned lines.
Complied
Sl. No. Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
1 Mail dated 30.01.2018:
Reviewed. The Zone 3 Settings kept as 1 Sec, in case it is
crossing the next voltage level the same was kept as 1.5Sec
Complied
2 Mail dated 30.01.2018:
Reviewed and found in line with OEM recommendations
Complied
3 Mail dated 30.01.2018:
Reviewed and found correct
Complied
4 Mail dated 30.01.2018:
In Siemens relay Zone-5 kept enabled
Complied
Sl. No. Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
1 Mail dated 30.01.2018:
Reviwed. The Zone 3 Settings kept as 1 Sec, in case it is
crossing the next voltage level the same was kept as 1.5Sec.
Mail dated 13.02.2018:
The Timer will come into picture after the CVT fuse fail delay
and is non directional. Hence maximum time delay of Zones kept
as 1.1sec which meets the functional Requirement. Reducing the
same might result in unsuccesful auto-reclosure.
PendingVT Fuse fail time delay which is presently kept as 1.1 sec may be suitably revised to say 0.5 sec
4) 400/ 220 kV Kozhikode SS [21-22 December, 2017]
Deficiences/Nonconformity observed
3) 400 kV Alundur SS [16 December, 2016]
Deficiences/Nonconformity observed
Zone-3 Time settings, which were presently kept at 1.5 sec to be suitably reviewed.
In Karaikudi Main-II relay, SOTF - Auto INIT, which was kept enabled, is to be reviewed
Resitive reaches for P-E faults for Zone-1 & Zone-2 of all feeders may be reviewed
Zone-5 of Main-I in Karaikudi feeders was kept enabled.
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auditated
Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
2 Mail dated 30.01.2018:
Under Review.
Mail dated 13.02.2018:
Kept as 100msec of Protected line which will cater the functional
requirement as per the organizational Philosophy. In case of
inadvertant initiation, the line might trip with a delay of 50ms for
even an outzone fault. 100ms is given to let the primary
protection of the downstream line operate.
Pending
3 Mail dated 30.01.2018:
To be Provided.
Mail dated 13.02.2018:
As per the Recommendations, the same will be provided. The
requiered hardware is under procurement and shall be
completed by April-18 end.
Pending
4 Mail dated 30.01.2018:
Under Review.
Mail dated 13.02.2018:
The Scheme studied in detail and compared with other few
stations. As the trippings are meant for different areas of
protections ( 400kV side and 220kV side seperately) and Gr-A
and Gr-B relays were provided with different DC sources, the
scheme is found to be Ok, which is in line with POWERGRID
Engineering Approval.
Pending
5 Mail dated 30.01.2018:
Under Review.
Mail dated 13.02.2018:
The Temporary ICT is provided to Cater the immediate load
relief to KSEB as per KSEB request, where common CB and CTs
were utilized. Upon Commissioning of New ICT-3, the ICT again
shall be kept as Spare.
Pending
Stub Protection Timing, which is presently kept as 100 msec may be suitably revised to 50 msec.
DC supply selector switch may be provided in 220 kV BBP panel
Providing of DOCE (HV) protection and DOCE (LV) protections of ICT's from different DC Sources may be explored.
Presenly Differential, DOCE (HV) & DOCE (LV) protections have been provided in common to 315 MVA ICT-2 and 315 MVA ICT-3
as a temporary arrangement. However, it is noted that with the commisssioning of new 500 MVA ICT in place of the existing ICT-3
(expected in 2 months), the above protections would be made independent.
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auditated
Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
Sl. No. Bay name/Bus Voltage Protection/Element/
Equipment/ System
auditated
Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
1 Chandrapur 2 400 kV Isolator Marshalling Box Observed that Control Supply Fuse of Isolator (389B) was in removed
condition.
Mail dated 30.01.2018:
Control Supply fuse placed
Complied
2 Chandrapur 1 & 2 400 kV Protection Panel Observed that Auto Recloser of Circuit Breaker is kept off Mail dated 30.01.2018:
AR kept in service
Complied
3 Chandrapur 1 & 2 400 kV Main-I relay & Main-II
relay
Zone-4 timer is kept as 1.0 sec Mail dated 30.01.2018:
Z-4 time delay made to 0.5Sec
Complied
4 Chandrapur 1 & 2 400 kV Protection panel Over Voltage stage-II time delay is kept as 0 sec. Mail dated 30.01.2018:
OV St-II Time Delay kept at 0.1Sec
Complied
5 Chandrapur 1 & 2 400 kV Protection Panel Redundant Overvoltage Stage-I protection is not available. Mail dated 30.01.2018:
OV St-I protection made available
Complied
6 Chandrapur 1 & 2 400 kV Protection Panel Observed that STUB protection is not available. Mail dated 30.01.2018:
Will be implemented.
Mail dated 13.02.2018:
Will be implemented by 30.06.2018.
Pending
7 Warangal 400 kV Main-I relay (ABB
RAZFE)
Reverse Zone is not available. Mail dated 30.01.2018:
Relay retroftitted with numerical relay & reverse zone
implemented
Complied
8 Warangal 400 kV Main-II relay Zone-3 time delay is kept as 1.2 s and Zone-4 time delay is kept as 1.0 s. Mail dated 30.01.2018:
Z-3 time delay changed to 1Sec & Z-4 time delay changed to
0.5Sec
Complied
9 Warangal 400 kV Protection panel Over Voltage stage-II time delay is kept as 0 sec. Mail dated 30.01.2018:
OV St-II Time Delay kept at 0.1Sec
Complied
10 N.Sagar 1 & 2 400 kV Protection panel Over Voltage stage-II time delay is kept as 0 sec. Mail dated 30.01.2018:
OV St-II Time Delay kept at 0.1Sec
Complied
11 N.Sagar 1 & 2 400 kV Main-II relay Observed that line Phase angle is kept as 75 degree (P-P) & 70 degree (P-
N).
Mail dated 30.01.2018:
Relay replaced with numerical relay & Phase angle changed to
75deg
Complied
12 N.Sagar 1 & 2 400 kV Main-I relay Observed that zone-4 time delay is kept as 1.0 s Mail dated 30.01.2018:
Z-4 time delay kept to 0.5Sec
Complied
13 N.Sagar 1 & 2 400 kV Main-II relay Observed that zone-3R time delay is kept as 1.3 s Mail dated 30.01.2018:
Z-3R (Rev zone)time delay kept to 0.5Sec
Complied
14 Gajwel 400 kv Main-1 relay Observed that zone-4 time delay is kept as 1.3 sec Mail dated 30.01.2018:
Z-4 time delay kept to 0.5Sec
Complied
NTPC
1) 400 kV Ramagundam STPS [18-20 February, 2016]
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auditated
Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
15 Gajwel 400 kv Main-I & II relay Observed that Zone-2 time delay is mismatching with main-I (500 ms)
and main-II(400 ms) relay.
Mail dated 30.01.2018:
Both Main-I&II Z-2 Time delay kept at 0.4Sec
Complied
16 Malkaram 400 kv Main-I & II relay Observed that time delay for Over Voltage Stage-II is mismatching with
numerical relay and static relay. Numerical relay time delay is 50 ms
whereas in static relay is kept 0 sec.
Mail dated 30.01.2018:
OV St-II Time Delay kept at 0.1Sec for both numerical & static
relays
Complied
17 Malkaram 400 kV Main-I& II relay Observed that zone-4 time delay is kept as 1.0 s Mail dated 30.01.2018:
Z-4 time delay kept to 0.5Sec
Complied
18 Tie feeder 400 kV Control Panel Auto recloser reclaim time delay is kept as 2.5 sec and dead time delay is
kept as 0.5 sec.
Mail dated 30.01.2018:
AR Reclaim time kept at 25 Sec & dead time kept at 1Sec.
Complied
19 Hyderabad-3&4 400 kV Protection panel Observed that zone-4 time delay is kept as 1.0 s Mail dated 30.01.2018:
Z-4 time delay kept to 0.5Sec
Complied
20 Hyderabad-3&4 400 kV Protection panel Observed that time delay for Over Voltage-II is mismatching with
numerical relay and static relay. Numerical relay time delay is 50 ms
whereas in static relay is kept 100 sec.
Mail dated 30.01.2018:
OV St-II Time Delay kept at 0.1Sec for both numerical & static
relays
Complied
21 Dichipally 400 kV Main-I relay Zone-4 time delay is kept as 1.3 s Mail dated 30.01.2018:
Z-4 time delay kept to 0.5Sec
Complied
22 Dichipally 400 kV Main-I relay Over Voltage stage-II is not enabled. Mail dated 30.01.2018:
Relay replaced with numerical realy & OV St-II is enabled
Complied
23 Dichipally 400 kV Main-II relay Zone-4 time delay is kept as 1.3 s Mail dated 30.01.2018:
Z-4 time delay kept to 0.5Sec
Complied
24 Dichipally 400 kV Main-II relay Over Voltage stage-I is not enabled. Mail dated 30.01.2018:
OV st-I presenlty in enabled condition
Complied
25 Dichipally 400 kV Control Panel Auto reclousre reclaim time delay is kept as 30 sec and dead time delay is
kept as 0.939 sec.
Mail dated 30.01.2018:
AR Reclaim time kept at 25 Sec & dead time kept at 1Sec.
Complied
26 Bus Reactor 400 kV Circuit Breaker
Marshalling Box
Circuit Breaker Pole Discreprency time delay is kept as 1.5 sec. Mail dated 30.01.2018:
PD timing set to 0.5Sec
Complied
27 Bus Reactor 400 kV Control Panel For LBB protection of Bus reactor, Current settings is at 0.05 In. Mail dated 30.01.2018:
Settings adopted are in line with our Engg recommendations.
The FL CT secondary current for reactor is 0.12A.
Complied
28 General Switchyard (ACDB) Auxiliary supply 415 V emergency feeder from DG
set is kept in test mode. The operation of changeover from normal supply
to Emergency DG supply is done manually.
Mail dated 30.01.2018 & 13.02.2018:
It is as per the scheme. Breaker presently kept in service
position.
Pending
29 General All Isolators are operated from local. Mail dated 30.01.2018:
Remote operation is available for all isolators. As per the local
practise & for extra safety local operation is being done
Complied
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auditated
Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
30 General Auto recloser is enabled for main CB's only and disabled for all tie CBs. Mail dated 30.01.2018:
AR enabled for all Tie CB's
Complied
31 General Some of the Isolator Marshalling Boxes and CTs Junction Boxes in stage I
installations are found rusted.
Mail dated 30.01.2018:
Few are in rusted condition. Replacement being done in phased
manner.
Mail dated 13.02.2018:
The Marshalling Boxes rust has been removed & suitably painted
Complied
32 General Cable for Manual Testing Solenoid is found disconnected in emulsifier
system for Shunt Reactor1.
Mail dated 13.02.2018:
Completed.
Complied
33 General Pressure gauge for Emulsifier system of Shunt Reactor 2 found not
working.
Mail dated 13.02.2018:
Will be replaced by 31.03.2018.
Pending
34 General Electric fuses from control panel of emulsifier system of Shunt Reactor 1
and 2 are in removed condition.
Mail dated 30.01.2018:
Fuses placed
Complied
35 General One of the PLCC II charger (48V) is giving alarm as rectifier fuse fail Mail dated 30.01.2018:
Rectified during Battery Load Test
Complied
36 General One of the Pressure gauge for Emulsifier system for Bus Reactor found
defective.
Mail dated 13.02.2018:
Will be replaced by 31.03.2018.
Pending
37 General In protection chnl I & II and speech chnl panels alarm indication for -Va
is appearing
Mail dated 30.01.2018:
Rectified
Complied
38 General Load enchrochment is not available in 400 kV feeders. However it was
informed that the resistive reach have been suitably calculated to take
care of the same excluding the 400kV Hyderabad line-3 & 4 (Main-2).
Mail dated 13.02.2018:
Load Encrochment is provided in Hyderabad Line-3,4(Main-2).
Complied
39 General STUB is enabled only for 400kV Malkaram, Warangal & Hyderabad 3 & 4
as instantaneous.
Mail dated 30.01.2018:
Settings are as per our NTPC practice.
Mail dated 13.02.2018:
Exisitng is electromechanical Scheme. Will be implemented in
numerical relay by 31.10.2018.
Pending
40 General For Main-2 protection of 400kV Chandrapur line- 1 & 2 and Main-1
protection of 400kV Nagarjunasagar line-1 & 2, Zone 1 & Zone 2 is
Unblock condition for PSB.
Mail dated 13.02.2018:
Settings are as per our NTPC practice.
Pending
NPCIL
1) 220 kV Kaiga GS [4-6 April, 2016]
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Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
Sl. No. Bay name/Bus Voltage Protection/Element/
Equipment/ System
auditated
Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
1 Control and
Protection
Panels/Relay Setting
For ICT-1&2 Differential and REF protection is provided in the same relay
(P663).
NPCIL Reply 2016:
Ramakrishna report does not call for separate relays for DIFFL
and REF. REF protection is provided as main protection to detect
senstive earth faults. Since differential and REF belongs to main
protection single relay can be used for both protections.
NPCIL Mail dated 25.01.2018:
As per the original design Differential and REF protection for ICT-
1&2 are provided in the same relay (ALSTOM-P633). The issue is
being taken up with designer for further reviews.
NPCIL Reply during Special Meeting at Kaiga dated
22.06.2018:
Agreed to put separate relays as per reliabililty requirements.
Separate relays for ICT-1&2 Differential and REF protection will
be provided by December 2018
Pending
2 Over current protection(67 forward) has been kept enabled on all 220 kV
feeders.
NPCIL Reply 2016:
Earlier Main-II distance protection was not provided. Hence this
protection was kept as a back up.Now this protection will be
deleted from trip as Main-II is available.
NPCIL Mail dated 25.01.2018:
All high set elements in Dir overcurrent is removed. IDMT O/C
(67 F) is only enabled as these lines are single ACSR moose with
a maximumcurrent rating of 603 amps at 75 deg C. The setting
is 800 amps with TMS0.25 onIEC-SI curve.
Complied
3 LBB time setting for lines is 0.25 sec and for ICTs - 0.2 sec. NPCIL Reply 2016:
It is being reviewed by NPCIL
NPCIL Mail dated 25.01.2018:
It has been reviewed and decided to keep settings as 200 msec
for all. Will be completed after receiving approval letter from HQ.
NPCIL Reply during Special Meeting at Kaiga dated
22.06.2018:
Received approval letter from HQ. LBB time setting for ICTs and
lines will be set to 200ms after availing shutdown.
Pending
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auditated
Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
4 Two sources of 48 V DC are available for PLCC communication. One
common output bus is extended to the PLCC panel.
NPCIL Reply 2016:
PLCC panels are supplied, installed and maintainind by the
owner of the 220 KV line(KPTCL).
NPCIL Mail dated 25.01.2018:
Two separate PLCC channels are available foraigaKadra and
kaiga Kodasalli lines. They have two independent 48 V DC power
supplies which is having automatic back up at the source side.
Complied
5 Communication
system
No separate speech channel is provided. But used through PLCC MDX-50
Exchange for communication.
NPCIL Reply 2016:
PLCC panels are supplied, installed and maintainind by the
owner of the 220 KV line(KPTCL).
NPCIL Mail dated 25.01.2018:
PLCC panels are supplied, installed and maintainind by the
owner of the 220 KV line(KPTCL). Hence the issue may be taken
up with KPTCL
Pending
6 Main- 1 and Main-2 Relays are not time-synchronized with GPS but
Standalone Disturbance and Event logger are time synchronized with
Station Clock which is time synchronized with GPS.
NPCIL Reply 2016:
In KGS numerical relays are not being used for event analysis.
Stand alone DR and event logger are GPS synchronised and
used for preparing trip reports. Thus unavailability of GPS
synchronisation of numerical relay does not affect the trip
analysis.
NPCIL Mail dated 25.01.2018:
Presently Stand aalone Disturbance recorder and event logger,
which are synchronised with GPS, are used for event analysis.
GPS is being procured for synchronising MainI&II relays by June,
2018.
NPCIL Reply during Special Meeting at Kaiga dated
22.06.2018:
GPS will be procured for time synchronising of MainI&II relays
by December, 2018.
Pending
Sl. No. Bay name/Bus Voltage Protection/Element/
Equipment/ System
auditated
Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
1 Bus Reactor-2 400KV Equipment Oil Leakage was observed in 400KV system Bus Reactor-2 neutral side
bottom valve.
NLCIL Mail dated 18.01.2018:
Oil leakage attended.
Complied
2 ICT-1&2 - Equipment Oil seepage was observed in the ICT-1 & 2. Also water leakage was
found near ICT-1
NLCIL Mail dated 18.01.2018:
Oil seepage and water leakage attended.
Complied
NLCIL
1) 400 kV NLC TS-II [8–10 February, 2016]
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Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
3 Tie-1 (230 kV), Tie-
2 (230 kV), STCMS
(230 kV), Tie-3
(400 kV) & Tie-4
(400 kV)
400KV &
230KV
Protection Even though there are four short lines [Tie-1 (230 kV), Tie-2 (230 kV),
STCMS (230 kV), Tie-3 (400 kV) & Tie-4 (400 kV)], line differential
protection has been provided on Tie-4 only.
NLCIL Mail dated 18.01.2018:
In 230kV Tie1 & Tie2 feeders , 2 nos of new relays with main
differential protection and backup distance protection relays
were commissioned. At present distance protection is in service.
Diferential protection will be commissioned shortly. The
possibility of introducing Differential relays in 400kV Tie3 feeder
and 230kV STCMS feeder has to be explored.
Pending
4 Nagapatnam line
bay
400KV Equipment The line CVT (Y-ph) of 400KV Nagapatnam line was not healthy, and
showing higher indication. As such, Over Voltage protection setting
(stage-I) for Nagapatnam line was set at higher value (128%)
NLCIL Mail dated 18.01.2018:
The Y phase CVT was replaced on 20-02-2016.
Complied
5 All the line feeders 400KV &
230KV
Protection Over current protection was kept enabled on some of the 400 kV feeders
(Pugalur, Nagapattinam, Tie-4), which should be kept disabled.
NLCIL Mail dated 18.01.2018:
Over current protections are kept disabled.
Complied
6 All the line feeders 400KV &
230KV
Protection DEF (Backup earth fault) protection was not provided on any of the 400
kV feeders. On some of the 400KV & 230KV feeders, it was kept non-
directional.
NLCIL Mail dated 18.01.2018:
Backup earth fault protection (DEF) was enabled for all feeders.
Complied
7 ICT -1 & 2 400KV/23
0KV
Protection For ICT -1 & 2, REF was not provided. However, it is observed that
circulating current protection has been provided in place of REF.
NLCIL Mail dated 18.01.2018:
Since ICT1 & 2 are single winding transformers the protection
provided is sufficient.
Pending
8 Bus Reactor 400KV Protection For Bus Reactor 1&2, Over voltage protection was kept enabled. Also no
REF has been provided to any of the bus reactors.
NLCIL Mail dated 18.01.2018:
Over voltage protection in Reactors was disabled.Restricted
earth fault (REF) protection was not envisaged in the original
design.
Pending
9 Bahoor Line feeder 230KV Equipment For 230 kV feeders (except Bahoor feeder), Main-1 protection only has
been provided. For Bahoor feeder, even though Main-1 & Main-2 relays
were provided, it is observed that both relays are of same make & model.
NLCIL Mail dated 18.01.2018:
A proposal has been taken up for providing Main 2 distance
protection in 230kV feeders. The equipments of Bahoor feeder
are assets of PGCIL. Any decision for replacement in Bahoor
feeder is in PGCIL scope.
Pending
10 All the line feeders 230KV Protection For 230 kV feeders, Power swing was blocked for all Zones and the
unblocking time was kept at 80 msec.
NLCIL Mail dated 18.01.2018:
Power swing block was provided from Z2 to Z5 zones and the
unblocking time has been kept at 2.0 sec as per guidelines.
Complied
11 All the line feeders
except Bahoor
230KV Protection A/R was not provided on 230 kV feeders except Bahoor & Villianur
feeders. On Bahoor feeder, A/R, though commissioned, not put into
service. On Villianur, A/R is in service.
NLCIL Mail dated 18.01.2018:
The Auto reclose implementation in the remaining 230kV feeders
will be taken up shortly.
Pending
12 Bus Bar Protection All 230KV feeder relays (Main-1), were provided with only one DC source.
It is observed that the second DC supply was available in relay panel.
However, no changeover arrangement for DC supply has been provided.
NLCIL Mail dated 18.01.2018:
The Control and relay panels are more than 30 years old .As the
space available in the 230kV panels is very limited to
accommodate DC changeover scheme ,the possibility of
providing DC change over scheme will be explored.
Pending
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Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
13 Bus Bar Protection 400KV & 220KV Busbar protection was provided with only one DC
source. It is observed that the second DC supply was available in relay
panel. However, no changeover arrangement for DC supply has been
provided.
NLCIL Mail dated 18.01.2018:
It has been proposed to replace the existing bus bar protection
with low impedance busbar protection The necessary Dc
changeover scheme will be introduced during the replacement
time.
Pending
14 All the line feeders 400KV &
230KV
Protection For all line feeders, the resistive reaches of all zones need modification.
NLC informed that the Consultant recommended settings were based on
the CVT ratio of 230 kV/ 110 V and 400 kV/ 110 V. However, as the
existing CVT ratios are 230 kV/ 115 V and 400 kV/ 115 V, the final
settings based on the existing ratios of CVT's would be implemented as
and when Consultant provides the same to them.
NLCIL Mail dated 18.01.2018:
Resitive reach for all the zones were modified as per the
consultant recommendations.
Complied
15 All the line feeders 230KV Protection In all 230KV line feeders SOTF function were kept disabled. NLCIL Mail dated 18.01.2018:
SOTF function is kept enabled.
Complied
16 MF-1,2,3&4 230KV Protection Eventhough MF-1,2,3&4 are short lines, PUT scheme has been
implemented.
NLCIL Mail dated 18.01.2018:
The feeders are radial. System is normal with PUT (Permissive
Under reach Transfer trip)
Pending
17 Pondy Line Bay 400KV Protection It is observed that in distance protection 5 zones are enabled. Zone-3
and Zone-4 settings were kept identically.
NLCIL Mail dated 18.01.2018:
Zone 3 & Zone 4 settings are always kept identically.
Pending
18 General 415V ACDB It is observed that manual Changeover arrangement only has been
provided between Incomer -1 & Incomer-2 feeder in ACDB and DCDB.
NLCIL Mail dated 18.01.2018:
Since ACDB and DCDB does not add any criticality to the system
manual change over is sufficient to take care of the situation
needs.
Pending
19 General 415V DG set No dedicated DG set for switchyard auxiliaries. Generation plant
emergency DG set power is utlised for switchyard emergency lighting
only.
NLCIL Mail dated 18.01.2018:
Emergency supply is taken from the emergency bus of the main
plant.
Complied
20 General - Equipment Cables laying in ACDB & DCDB room is observed to be overloaded in
cable trays and some of the cables laid haphazardly (not properly laid in
Cable trays)
NLCIL Mail dated 18.01.2018:
Cables re-arrangement is in progress.
Pending
21 General - Equipment In ACDB & DCDB and Battery Charger panel, no Indication Lamps were
provided.
NLCIL Mail dated 18.01.2018:
Indication lamps provided.
Complied
22 General - DC system It is observed that no earthing has been provided in 220V & 48V DC
Battery room for measurement purpose. Exhaust fans are not provided in
one of the 48V Battery room
NLCIL Mail dated 18.01.2018:
Attended
Complied
23 General - DC system Earth fault was observed in DC source-2. The voltage measured values
are : +ve to -ve = 238.3V; +ve to earth = 65.3V; -ve to earth = 172.6V
NLCIL Mail dated 18.01.2018:
Earth fault in the system was cleared.
Complied
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auditated
Deficiences/Nonconformity observed Status of Implementation of Protection Audit
Recommendations
Remarks Latest Status (To be filled up by the
Constituent)
24 General - Protection Pole discrepancy (PD) for all the line & tie feeder breakers are not kept
uniform. For all 400 kV feeders except tie-feeders kept as 2.4sec; For
400 kV Tie-feeders, 230 kV feeders, ICT & Reactor breaker, it was kept at
0.1 second.
NLCIL Mail dated 18.01.2018:
For the breakers of all feeders which are provided with auto
reclose facility the Pole descrepancy is kept at 2.4 sec. For all
other breakers , pole descrepancy is kept at 100msec.
Complied
25 General - Equipment Most of the circuit breaker cubicles in 400KV & 220KV feeders have not
been provided with panel lamp. Door switches were also not working
properly.
NLCIL Mail dated 18.01.2018:
Provided.
Complied
26 General - Equipment Star ground connection for 400KV extension feeders (viz., Tie-3, Tie-4,
Pugalur) and Bus Reactor-1 & 2's CT/CVT are done in protection panel in
control room. All other 400KV & 220KV feeders CT/ CVT star ground
connection provided in field (switchyard).
NLCIL Mail dated 18.01.2018:
The existing arrangemnt works properly and needs no changes.
Pending
27 General - Equipment It is observed that single earthing has been provided for few marshalling
boxes in switchyard. Also Door earthing was not provided for the
marshalling boxes. NLC confirmed that marshalling box replacement
works are under progress.
NLCIL Mail dated 18.01.2018:
A total of 62 nos of marshalling kiosks have been replaced so far
with double earthing and door earthing. Replacement of balance
marshalling kiosks will be taken up shortly.
Pending
28 General - Equipment Rusting was observed in most of the 400KV & some of the 220KV CT/CVT
Marshalling Boxes. Some of the CT/CVT Marshalling Boxes have not been
body earthed. The dummy gland holes in marshalling boxes were not
covered. NLC confirmed that marshalling box replacement works are
under progress.
NLCIL Mail dated 18.01.2018:
A total of 62 nos of marshalling kiosks have been replaced so
far. Replacement of balance marshalling kiosks will be taken up
shortly.
Pending
29 General - Equipment CB open/close Indication Lamps were not provided in 400KV system
feeder local Circuit breaker panels.
NLCIL Mail dated 18.01.2018:
Existing 400kV breakers which are very old are being replaced in
phased manner. Six nos of breakers have already been replaced
with proper indication lamps at local.
Pending
30 General 400KV &
230KV
Protection No MICOM relay is time synchronised with GPS system. New set of relays with GPS synchronisation is being purchased
to replace the old version MICOM P437 relays.
Pending
31 General - Equipment It was observed that standalone Event Recorder with automatic
downloading facility to centralized PC not provided.
NLCIL Mail dated 18.01.2018:
Numerical relays provided have built in event records &DR.
Complied
32 General - Equipment It was observed that most of unused cutouts in Relay panels (both 400
kV & 230 kV) in control room were not covered.
NLCIL Mail dated 18.01.2018:
All unused cutouts were covered.
Complied
70/70
Annexure-VI
Page 70 of 70