SOUTHERN REGIONAL POWER COMMITTEE BENGALURU

SOUTHERN REGIONAL POWER COMMITTEE BENGALURU Additional Agenda for the 80 th Meeting of Protection Coordination Sub-Committee of SRPC to be held on 20-21 December, 2018 1. Grid Occurrences Additional Grid Additional Tripping Events that occurred during the period November, 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) (b) (c) Single line diagram of the station with switching devices, CT, PT and relay details. Cause of the tripping & Remedial Action taken Relay setting details Constituents are requested to bring/ furnish full particulars of the tripping events pertaining to their system. 2. Conduction of Protection Audit of various Stations (Substations as well as Generation Switchyards) at Transmission & Distribution level and Model Protection Audit Formats You are kindly aware that at regional level protection audit of various 220 kv & above Stations (Substations as well as Generation Switchyards) are being conducted by different SRPC Teams (comprising members from different SR-Constituents) in line with CERC Order dated 27.04.2015 in respect of APTRANSCO Petition no: 95/MP/2015 and CERC Order dated 14.05.2015 in respect of TSTRANSCO's Petition no: 83/MP/2015. These audits are being conducted using the model protection audit formats given by the Consultant, M/s Tractebel Engineering, with some modifications (copy enclosed at ). However, since ensuring healthiness of protection systems at all stations (generation/ transmission/ distribution) is important for integrated grid operation, conducting protection audit of these stations assumes significance. While the issue is under discussion at national level bodies like NPC/ CEA, Hon ble CERC also vide their Order dated 26.03.2018 in Petition No. 09/ SM/ 2015 has directed RPC s to take up the issue of protection audit and relay setting in transmission system / distribution system within States with all concerned. In this regard, it is proposed to discuss the practices being followed by various SR-Constituents in conducting protection audit of their own stations and the help they are rendering to respective DISCOMs in this regard. Accordingly, APGENCO, APTRANSCO, TSGENCO, TSTRANSCO, KPCL, KPTCL, KSEBL, TANGEDCO, TANTRANSCO, KSEBL, PGCIL (SR-I) are requested to kindly submit & present the action being taken by them ***** Additional Agenda for the 80 th Meeting of PCSC scheduled to be held on 20-21 December, 2018 Page 1

Grid Occurrences - 80 Annexure-I 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 Incidents: Sl. No. Details of Event Date &Time Reason Category 1 2 3 4 5 Tripping of 400kV Kalpakka-Gazuwaka Ckt- 1 &2 Tripping of 400/220kV ICT-1 at Kaiga Tripping of 400kV Kaiga- Guttur Ckt-1 and 400/220kV ICT-1 at Kaiga. Tripping of 400kV Nellore PS SGPL Ckt-1 Tripping of 400kV Uravakonda-Veltoor Ckt-2 09-11-2018 at 16:47 Hrs 13-11-2018 at 09:14 Hrs 13-11-2018 at 16:00 Hrs 14-11-2018 at 20:20 hrs 19-11-2018 at 12:00 Hrs 400kV Kalpakka-Gazuwaka Ckt-1&2 tripped due to relay maloperation during through fault. SOTF protection maloperated due to problem with the settings and DT was sent to Kalpakka end. As reported, while opening od 400kV Kaiga-Guttur Ckt-1 at Guttur end for maintenance, LBB protection operated on pole discrepancy resulting in tripping of ICT-1 at Kaiga. As reported 400kV Kaiga-Guttur-Ckt-1 tripped on B-phase to ground fault. At the same time 400/220kV ICT-1 at Kaiga tripped on operation of LBB protection due to pole discrepancy. Y- phase to earth fault occurred in line due to snapping of GIS to Air bushing conductor at NCC switchyard. The conductor got grounded such that fault was being fed by NPS bus and there was earth fault and broken conductor start at SGPL end. NPS end got tripped in zone-2 due to non-receipt of carrier resulting in a 3 phase trip at NPS. After 500ms, earth fault occurred at SGPL end resulting in zone-1 operation and 3 phase trip. A/r was not attempted at SGPL end As per FIR, 400kV Uravakonda - Veltoor Ckt-2 tripped on operation of overvoltage Stage-1 at Uravakonda end and DT received at veltoor end. From the DR furnished, voltages at Uravakonda end are: Vr- 243kV, Vy-245kV and Vb-242kV. From the DR operation of Overvoltage Stage-1 protection could not be established. Over voltage grading of the line at Uravakonda end is 109%, 6secs, tripping is not as per grading. GI-2 GI-2 GI-2 GI-2 GI-2 Grid Occurrences to be discussed in the 80 th Meeting of PCSC scheduled to be held on 20-21 December, 2018 1/2

II. Details of Trippings due to Failure or Non-operation of Auto-Reclose: Annexure-I Sl. No. Element Date & Time Reason 1 Tripping of 400kV Gooty Nelamangala 27-11-2018 at 00:43 Hrs B-phase to earth fault occurred in line. Autoreclose was successful at Nelamangala end. At gooty end auto-reclose did not operate. Pole discrepancy operation was observed form EL of gooty end. After 8 sec, over voltage operation got operated at Gooty end resulting in DT send to Nelamangala and tripping of line III. Details of Trippings due to PLCC mal-operation: Sl. No. Element Date & Time Reason 1 Tripping of 400kV Ghani- Narnoor Ckt-2 14-11-2018 at 16:46Hrs 400kV Ghani - Narnoor ckt-2 tripped at Narnoor end on DT receipt due to mal operation of PLCC signal. Line did not trip at Ghani end. ***** Grid Occurrences to be discussed in the 80 th Meeting of PCSC scheduled to be held on 20-21 December, 2018 2/2

General Information: Substation Name: SS Voltage level: PROTECTION AUDIT REPORT Fault level of all Equipment (for both 3-ph & 1-ph faults at all voltage levels) Audit Team: Date of commissioning of the substation: Region: Audit Date: Name of the Utility which owns the Substation Name Southern Region Organization Name Auditee Team: Name Organization Name Attached Documents: 1 Detailed Single Line Diagram of the Substation 2 Protection Philosophy being followed 3 Adopted Relay Settings (given by Head Quarters/ Corporate Office) 4 Extracted Relay Settings (in PDF format) 5 Calculation Sheet(s) showing protection settings calculation for all feeders and transformers 6 AC Supply Changeover Scheme 7 Details on Periodicity of Relay Testing and latest Relay Test Reports Southern Region - (Station Name) 1/58 Page 1 of 58

8 9 10 11 12 13 Details of Measurement of Dependability & Security of PLCC Channels CT Characteristics at all Taps in case of multi-ratio CTs Details of Measurement of Station Earth-Mat & Earth-Pits Details & Settings of df/dt and UF Relays, if applicable Details of Special Protection Schemes details, if applicable (including implemented schematic diagram for SPS, test results, last operation records) Record of previous Trippings for last six months and associated Fault Analysis. Southern Region - (Station Name) 2/58 Page 2 of 58

(Capacity) MW Generator Unit-1 Protection Audit - check list No Relay configuration - Generator protections 1 Name, voltage, power 2 Are used 2 groups of protections (Group A and Group B) for Gen. Unit protection? 3 Are Group A and Group B protections connected to separate DC sources for Gen. Unit? 4 Do the Group A and Group B protections have separate lockout relays? Details of type relays Details of composite type numerical relays Relay make and model Main Back up A B C D Other Protections Whether the relay is functional? Date of testing Mention all the active protections Differential protection 100% Stator Earth Fault protection 95% Stator Earth Fault protection 5 Inter-turn Fault protection Loss of Excitation protection Negative Phase Sequence Current protection Low Forward Power/ Reverse Power protection Out-of-step/ Pole slipping protection Over-Voltage protection Under-frequency protection Back-up Impedance protection Accidental back-energisation/ Dead machine protection Rotor Earth-Fault protection Thermal Over-load protection Breaker failure active Disturbance Report active 6 Connected to Trip Coil 1/Trip Coil2/Both 7 Feed from DC supply 1/DC supply2 Connected to dedicated CT core? 8 Define CT core no. to which the relay is connected 9 CT ratio selected 10 VT ratio selected Details of separate relays if applicable Relay 1 make and model Functions available in Relay 1 Southern Region - (Station Name) 3/58 Page 3 of 58

(Capacity) MW Generator Unit-1 Protection Audit - check list No Relay configuration - Generator protections Relay 1 Functional Relay 2 make and model 11 Functions available in Relay 1 Relay 2 Functional Relay 3 make and model Functions available in Relay 1 Relay 3 Functional 12 Are all the Lock out relays (86) considered for Gen. Unit protection provided with supervision relays (74/86)? 13 Do the Gen. Unit protection panels have supervision relays for DC supply-1 & DC supply-2 (74/DC-1 & 74/DC-2)? Southern Region - (Station Name) 4/58 Page 4 of 58

(Capacity) MW Generator Unit-2 Protection Audit - check list No Relay configuration - Generator protections 1 Name, voltage, power 2 Are used 2 groups of protections (Group A and Group B) for Gen. Unit protection? 3 Are Group A and Group B protections connected to separate DC sources for Gen. Unit? 4 Do the Group A and Group B protections have separate lockout relays? Details of type relays Details of composite type numerical relays Relay make and model Main Back up A B C D Other Protections Whether the relay is functional? Date of testing Mention all the active protections Differential protection 100% Stator Earth Fault protection 95% Stator Earth Fault protection 5 Inter-turn Fault protection Loss of Excitation protection Negative Phase Sequence Current protection Low Forward Power/ Reverse Power protection Out-of-step/ Pole slipping protection Over-Voltage protection Under-frequency protection Back-up Impedance protection Accidental back-energisation/ Dead machine protection Rotor Earth-Fault protection Thermal Over-load protection Breaker failure active Disturbance Report active 6 Connected to Trip Coil 1/Trip Coil2/Both 7 Feed from DC supply 1/DC supply2 Connected to dedicated CT core? 8 Define CT core no. to which the relay is connected 9 CT ratio selected 10 VT ratio selected Details of separate relays if applicable Relay 1 make and model Functions available in Relay 1 Southern Region - (Station Name) 5/58 Page 5 of 58

(Capacity) MW Generator Unit-2 Protection Audit - check list No Relay configuration - Generator protections Relay 1 Functional Relay 2 make and model 11 Functions available in Relay 1 Relay 2 Functional Relay 3 make and model Functions available in Relay 1 Relay 3 Functional 12 Are all the Lock out relays (86) considered for Gen. Unit protection provided with supervision relays (74/86)? 13 Do the Gen. Unit protection panels have supervision relays for DC supply-1 & DC supply-2 (74/DC-1 & 74/DC-2)? Southern Region - (Station Name) 6/58 Page 6 of 58

(Capacity) MVA, HV/ LV kv GT-1 Generator Transformer Protection Audit - check list No Relay configuration - Power Transformers protections 1 Name, voltage, power 2 Are used 2 groups of protections (Group A and Group B) for Gen. Transformer protection? 3 Are Group A and Group B protections connected to separate DC sources for Gen. Transformer? 4 Do the Group A and Group B protections have separate lockout relays? Details of type relays Details of composite type numerical relays Relay make and model Main Back up A B C D Other Protections Whether the relay is functional? Date of testing Mention all the active protections 5 Overall differential Differential protection REF protection Back-up directional O/C +E/F protection Overfluxing protection Connected to Trip Coil 1/Trip Coil2/Both Feed from DC supply 1/DC supply2 Breaker failure active Disturbance Report active Connected to dedicated CT core? Define CT core no. to which the relay is connected CT ratio selected Is CT supervision enabled or not in case of Gen. Transformer differential protection? 6 Are all the Lock out relays (86) considered for Gen. Transformer protection provided with supervision relays (74/86)? 7 Do the Transformer protection panels have supervision relays for DC supply-1 & DC supply-2 (74/DC-1 & 74/DC-2)? 8 OTI working 9 OTI working 10 Buchholtz working 11 PRD/ PRV working 12 LA rating HV side 13 LA rating IV side Southern Region - (Station Name) 7/58 Page 7 of 58

(Capacity) MVA, HV/ LV kv GT-2 Generator Transformer Protection Audit - check list No Relay configuration - Power Transformers protections 1 Name, voltage, power 2 Are used 2 groups of protections (Group A and Group B) for Gen. Transformer protection? 3 Are Group A and Group B protections connected to separate DC sources for Gen. Transformer? 4 Do the Group A and Group B protections have separate lockout relays? Details of type relays Details of composite type numerical relays Relay make and model Main Back up A B C D Other Protections Whether the relay is functional? Date of testing Mention all the active protections 5 Overall differential Differential protection REF protection Back-up directional O/C +E/F protection Overfluxing protection Connected to Trip Coil 1/Trip Coil2/Both Feed from DC supply 1/DC supply2 Breaker failure active Disturbance Report active Connected to dedicated CT core? Define CT core no. to which the relay is connected CT ratio selected Is CT supervision enabled or not in case of Gen. Transformer differential protection? 6 Are all the Lock out relays (86) considered for Gen. Transformer protection provided with supervision relays (74/86)? 7 Do the Transformer protection panels have supervision relays for DC supply-1 & DC supply-2 (74/DC-1 & 74/DC-2)? 8 OTI working 9 OTI working 10 Buchholtz working 11 PRD/ PRV working 12 LA rating HV side 13 LA rating IV side Southern Region - (Station Name) 8/58 Page 8 of 58

765 kv (Line Name) Line-1 Distance Protection Audit - check list No. Relay configuration - Line distance protection 1 Name and length of line 2 Series compensated? Y/N 3 Is this a cable feeder / line feeder/ composite feeder (line+cable)? 4 Which mode of communication is used (PLCC/ OPGW) 5 Details of composite type numerical relays Relay make and model Whether the relay is functional?? Date of testing Mention all the active protections Details of type relays Main-1 Relay Main-2 Relay Mode of Carrier aided scheme for 21 ( If POR scheme is used whether Current Reversal Guard Logic implemented?) Carrier aided scheme active for 67/67N Mode of Carrier aided scheme for 67/67N For 87L which scheme is used? (Pilot wire communication/ digital communication) Power swing/out of step active? SOTF active? Auto Reclose (79) active? Breaker failure active Load Encroachment active Stub Protection active Fault locator active? Disturbance Recorder active? 6 Relay Connected to Trip Coil-1/ Trip Coil-2 or both? 7 Feed from DC supply 1 / DC Supply 2 8 Connected to Dedicated CT core? Define CT core no. to which the relay is connected 9 CT ratio selected 10 VT ratio selected for ex: Siemens 7SA522 21/87L/ Accelerated Under reach/ Permissive Under reach/intertripping Under reach/ Permissive Overreach/ Blocking Over reach/ Phase Comparison Protection (for PLCC) Directional Comparison Protection (Permissive)/ Directional Comparison Protection (Blocking) Other Relays (Back-up relays, DR, FL etc.) Southern Region - (Station Name) 9/58 Page 9 of 58

765 kv (Line Name) Line-1 Distance Protection Audit - check list No. Relay configuration - Line distance protection Details of separate relays if applicable Relay 1 make and model Functions available in Relay 1 Relay 1 Functional Relay 2 make and model Functions available in Relay 2 Relay 2 Functional 11 Relay 3 make and model Functions available in Relay 3 Relay 3 Functional Relay 4 make and model Functions available in Relay 4 Relay 4 Functional 12 VT Fuse failure protection present & used to block distance function operation? 13 Overvoltage protection available Functional with two stage protection 14 Are all the auxiliary relays (94) considered for Line protection (Main-1/ Main-2/ Backup) provided with supervision relays (74/ 94)? 15 Do the Line Protection protection panels have supervision relays for DC supply-1 & DC supply-2 (74/DC-1 & 74/DC-2)? Southern Region - (Station Name) 10/58 Page 10 of 58

765 kv (Line Name) Line-2 Distance Protection Audit - check list No. Relay configuration - Line distance protection 1 Name and length of line 2 Series compensated? Y/N 3 Is this a cable feeder / line feeder/ composite feeder (line+cable)? 4 Which mode of communication is used (PLCC/ OPGW) 5 Details of composite type numerical relays Relay make and model Whether the relay is functional?? Date of testing Mention all the active protections Details of type relays Main-1 Relay Main-2 Relay Mode of Carrier aided scheme for 21 ( If POR scheme is used whether Current Reversal Guard Logic implemented?) Carrier aided scheme active for 67/67N Mode of Carrier aided scheme for 67/67N For 87L which scheme is used? (Pilot wire communication/ digital communication) Power swing/out of step active? SOTF active? Auto Reclose (79) active? Breaker failure active Load Encroachment active Stub Protection active Fault locator active? Disturbance Recorder active? 6 Relay Connected to Trip Coil-1/ Trip Coil-2 or both? 7 Feed from DC supply 1 / DC Supply 2 8 Connected to Dedicated CT core? Define CT core no. to which the relay is connected 9 CT ratio selected 10 VT ratio selected for ex: Siemens 7SA522 21/87L/ Accelerated Under reach/ Permissive Under reach/intertripping Under reach/ Permissive Overreach/ Blocking Over reach/ Phase Comparison Protection (for PLCC) Directional Comparison Protection (Permissive)/ Directional Comparison Protection (Blocking) Other Relays (Back-up relays, DR, FL etc.) Southern Region - (Station Name) 11/58 Page 11 of 58

765 kv (Line Name) Line-2 Distance Protection Audit - check list No. Relay configuration - Line distance protection Details of separate relays if applicable Relay 1 make and model Functions available in Relay 1 Relay 1 Functional Relay 2 make and model Functions available in Relay 2 Relay 2 Functional 11 Relay 3 make and model Functions available in Relay 3 Relay 3 Functional Relay 4 make and model Functions available in Relay 4 Relay 4 Functional 12 VT Fuse failure protection present & used to block distance function operation? 13 Overvoltage protection available Functional with two stage protection 14 Are all the auxiliary relays (94) considered for Line protection (Main-1/ Main-2/ Backup) provided with supervision relays (74/ 94)? 15 Do the Line Protection protection panels have supervision relays for DC supply-1 & DC supply-2 (74/DC-1 & 74/DC-2)? Southern Region - (Station Name) 12/58 Page 12 of 58

765 kv (Line Name) Line-3 Distance Protection Audit - check list No. Relay configuration - Line distance protection 1 Name and length of line 2 Series compensated? Y/N 3 Is this a cable feeder / line feeder/ composite feeder (line+cable)? 4 Which mode of communication is used (PLCC/ OPGW) 5 Details of composite type numerical relays Relay make and model Whether the relay is functional?? Date of testing Mention all the active protections Details of type relays Main-1 Relay Main-2 Relay Mode of Carrier aided scheme for 21 ( If POR scheme is used whether Current Reversal Guard Logic implemented?) Carrier aided scheme active for 67/67N Mode of Carrier aided scheme for 67/67N For 87L which scheme is used? (Pilot wire communication/ digital communication) Power swing/out of step active? SOTF active? Auto Reclose (79) active? Breaker failure active Load Encroachment active Stub Protection active Fault locator active? Disturbance Recorder active? 6 Relay Connected to Trip Coil-1/ Trip Coil-2 or both? 7 Feed from DC supply 1 / DC Supply 2 8 Connected to Dedicated CT core? Define CT core no. to which the relay is connected 9 CT ratio selected 10 VT ratio selected for ex: Siemens 7SA522 21/87L/ Accelerated Under reach/ Permissive Under reach/intertripping Under reach/ Permissive Overreach/ Blocking Over reach/ Phase Comparison Protection (for PLCC) Directional Comparison Protection (Permissive)/ Directional Comparison Protection (Blocking) Other Relays (Back-up relays, DR, FL etc.) Southern Region - (Station Name) 13/58 Page 13 of 58

765 kv (Line Name) Line-3 Distance Protection Audit - check list No. Relay configuration - Line distance protection Details of separate relays if applicable Relay 1 make and model Functions available in Relay 1 Relay 1 Functional Relay 2 make and model Functions available in Relay 2 Relay 2 Functional 11 Relay 3 make and model Functions available in Relay 3 Relay 3 Functional Relay 4 make and model Functions available in Relay 4 Relay 4 Functional 12 VT Fuse failure protection present & used to block distance function operation? 13 Overvoltage protection available Functional with two stage protection 14 Are all the auxiliary relays (94) considered for Line protection (Main-1/ Main-2/ Backup) provided with supervision relays (74/ 94)? 15 Do the Line Protection protection panels have supervision relays for DC supply-1 & DC supply-2 (74/DC-1 & 74/DC-2)? Southern Region - (Station Name) 14/58 Page 14 of 58

765 kv (Line Name) Line-4 Distance Protection Audit - check list No. Relay configuration - Line distance protection 1 Name and length of line 2 Series compensated? Y/N 3 Is this a cable feeder / line feeder/ composite feeder (line+cable)? 4 Which mode of communication is used (PLCC/ OPGW) 5 Details of composite type numerical relays Relay make and model Whether the relay is functional?? Date of testing Mention all the active protections Details of type relays Main-1 Relay Main-2 Relay Mode of Carrier aided scheme for 21 ( If POR scheme is used whether Current Reversal Guard Logic implemented?) Carrier aided scheme active for 67/67N Mode of Carrier aided scheme for 67/67N For 87L which scheme is used? (Pilot wire communication/ digital communication) Power swing/out of step active? SOTF active? Auto Reclose (79) active? Breaker failure active Load Encroachment active Stub Protection active Fault locator active? Disturbance Recorder active? 6 Relay Connected to Trip Coil-1/ Trip Coil-2 or both? 7 Feed from DC supply 1 / DC Supply 2 8 Connected to Dedicated CT core? Define CT core no. to which the relay is connected 9 CT ratio selected 10 VT ratio selected for ex: Siemens 7SA522 21/87L/ Accelerated Under reach/ Permissive Under reach/intertripping Under reach/ Permissive Overreach/ Blocking Over reach/ Phase Comparison Protection (for PLCC) Directional Comparison Protection (Permissive)/ Directional Comparison Protection (Blocking) Other Relays (Back-up relays, DR, FL etc.) Southern Region - (Station Name) 15/58 Page 15 of 58

765 kv (Line Name) Line-4 Distance Protection Audit - check list No. Relay configuration - Line distance protection Details of separate relays if applicable Relay 1 make and model Functions available in Relay 1 Relay 1 Functional Relay 2 make and model Functions available in Relay 2 Relay 2 Functional 11 Relay 3 make and model Functions available in Relay 3 Relay 3 Functional Relay 4 make and model Functions available in Relay 4 Relay 4 Functional 12 VT Fuse failure protection present & used to block distance function operation? 13 Overvoltage protection available Functional with two stage protection 14 Are all the auxiliary relays (94) considered for Line protection (Main-1/ Main-2/ Backup) provided with supervision relays (74/ 94)? 15 Do the Line Protection protection panels have supervision relays for DC supply-1 & DC supply-2 (74/DC-1 & 74/DC-2)? Southern Region - (Station Name) 16/58 Page 16 of 58

400 kv (Line Name) Line-1 Distance Protection Audit - check list No. Relay configuration - Line distance protection 1 Name and length of line 2 Series compensated? Y/N 3 Is this a cable feeder / line feeder/ composite feeder (line+cable)? 4 Which mode of communication is used (PLCC/ OPGW) 5 Details of composite type numerical relays Relay make and model Whether the relay is functional?? Date of testing Mention all the active protections Details of type relays Main-1 Relay Main-2 Relay Mode of Carrier aided scheme for 21 ( If POR scheme is used whether Current Reversal Guard Logic implemented?) Carrier aided scheme active for 67/67N Mode of Carrier aided scheme for 67/67N For 87L which scheme is used? (Pilot wire communication/ digital communication) Power swing/out of step active? SOTF active? Auto Reclose (79) active? Breaker failure active Load Encroachment active Stub Protection active Fault locator active? Disturbance Recorder active? 6 Relay Connected to Trip Coil-1/ Trip Coil-2 or both? 7 Feed from DC supply 1 / DC Supply 2 8 Connected to Dedicated CT core? Define CT core no. to which the relay is connected 9 CT ratio selected 10 VT ratio selected for ex: Siemens 7SA522 21/87L/ Accelerated Under reach/ Permissive Under reach/intertripping Under reach/ Permissive Overreach/ Blocking Over reach/ Phase Comparison Protection (for PLCC) Directional Comparison Protection (Permissive)/ Directional Comparison Protection (Blocking) Other Relays (Back-up relays, DR, FL etc.) Southern Region - (Station Name) 17/58 Page 17 of 58

400 kv (Line Name) Line-1 Distance Protection Audit - check list No. Relay configuration - Line distance protection Details of separate relays if applicable Relay 1 make and model Functions available in Relay 1 Relay 1 Functional Relay 2 make and model Functions available in Relay 2 Relay 2 Functional 11 Relay 3 make and model Functions available in Relay 3 Relay 3 Functional Relay 4 make and model Functions available in Relay 4 Relay 4 Functional 12 VT Fuse failure protection present & used to block distance function operation? 13 Overvoltage protection available Functional with two stage protection 14 Are all the auxiliary relays (94) considered for Line protection (Main-1/ Main-2/ Backup) provided with supervision relays (74/ 94)? 15 Do the Line Protection protection panels have supervision relays for DC supply-1 & DC supply-2 (74/DC-1 & 74/DC-2)? Southern Region - (Station Name) 18/58 Page 18 of 58

400 kv (Line Name) Line-2 Distance Protection Audit - check list No. Relay configuration - Line distance protection 1 Name and length of line 2 Series compensated? Y/N 3 Is this a cable feeder / line feeder/ composite feeder (line+cable)? 4 Which mode of communication is used (PLCC/ OPGW) 5 Details of composite type numerical relays Relay make and model Whether the relay is functional?? Date of testing Mention all the active protections Details of type relays Main-1 Relay Main-2 Relay Mode of Carrier aided scheme for 21 ( If POR scheme is used whether Current Reversal Guard Logic implemented?) Carrier aided scheme active for 67/67N Mode of Carrier aided scheme for 67/67N For 87L which scheme is used? (Pilot wire communication/ digital communication) Power swing/out of step active? SOTF active? Auto Reclose (79) active? Breaker failure active Load Encroachment active Stub Protection active Fault locator active? Disturbance Recorder active? 6 Relay Connected to Trip Coil-1/ Trip Coil-2 or both? 7 Feed from DC supply 1 / DC Supply 2 8 Connected to Dedicated CT core? Define CT core no. to which the relay is connected 9 CT ratio selected 10 VT ratio selected for ex: Siemens 7SA522 21/87L/ Accelerated Under reach/ Permissive Under reach/intertripping Under reach/ Permissive Overreach/ Blocking Over reach/ Phase Comparison Protection (for PLCC) Directional Comparison Protection (Permissive)/ Directional Comparison Protection (Blocking) Other Relays (Back-up relays, DR, FL etc.) Southern Region - (Station Name) 19/58 Page 19 of 58

400 kv (Line Name) Line-2 Distance Protection Audit - check list No. Relay configuration - Line distance protection Details of separate relays if applicable Relay 1 make and model Functions available in Relay 1 Relay 1 Functional Relay 2 make and model Functions available in Relay 2 Relay 2 Functional 11 Relay 3 make and model Functions available in Relay 3 Relay 3 Functional Relay 4 make and model Functions available in Relay 4 Relay 4 Functional 12 VT Fuse failure protection present & used to block distance function operation? 13 Overvoltage protection available Functional with two stage protection 14 Are all the auxiliary relays (94) considered for Line protection (Main-1/ Main-2/ Backup) provided with supervision relays (74/ 94)? 15 Do the Line Protection protection panels have supervision relays for DC supply-1 & DC supply-2 (74/DC-1 & 74/DC-2)? Southern Region - (Station Name) 20/58 Page 20 of 58

400 kv (Line Name) Line-3 Distance Protection Audit - check list No. Relay configuration - Line distance protection 1 Name and length of line 2 Series compensated? Y/N 3 Is this a cable feeder / line feeder/ composite feeder (line+cable)? 4 Which mode of communication is used (PLCC/ OPGW) 5 Details of composite type numerical relays Relay make and model Whether the relay is functional?? Date of testing Mention all the active protections Details of type relays Main-1 Relay Main-2 Relay Mode of Carrier aided scheme for 21 ( If POR scheme is used whether Current Reversal Guard Logic implemented?) Carrier aided scheme active for 67/67N Mode of Carrier aided scheme for 67/67N For 87L which scheme is used? (Pilot wire communication/ digital communication) Power swing/out of step active? SOTF active? Auto Reclose (79) active? Breaker failure active Load Encroachment active Stub Protection active Fault locator active? Disturbance Recorder active? 6 Relay Connected to Trip Coil-1/ Trip Coil-2 or both? 7 Feed from DC supply 1 / DC Supply 2 8 Connected to Dedicated CT core? Define CT core no. to which the relay is connected 9 CT ratio selected 10 VT ratio selected for ex: Siemens 7SA522 21/87L/ Accelerated Under reach/ Permissive Under reach/intertripping Under reach/ Permissive Overreach/ Blocking Over reach/ Phase Comparison Protection (for PLCC) Directional Comparison Protection (Permissive)/ Directional Comparison Protection (Blocking) Other Relays (Back-up relays, DR, FL etc.) Southern Region - (Station Name) 21/58 Page 21 of 58

400 kv (Line Name) Line-3 Distance Protection Audit - check list No. Relay configuration - Line distance protection Details of separate relays if applicable Relay 1 make and model Functions available in Relay 1 Relay 1 Functional Relay 2 make and model Functions available in Relay 2 Relay 2 Functional 11 Relay 3 make and model Functions available in Relay 3 Relay 3 Functional Relay 4 make and model Functions available in Relay 4 Relay 4 Functional 12 VT Fuse failure protection present & used to block distance function operation? 13 Overvoltage protection available Functional with two stage protection 14 Are all the auxiliary relays (94) considered for Line protection (Main-1/ Main-2/ Backup) provided with supervision relays (74/ 94)? 15 Do the Line Protection protection panels have supervision relays for DC supply-1 & DC supply-2 (74/DC-1 & 74/DC-2)? Southern Region - (Station Name) 22/58 Page 22 of 58

400 kv (Line Name) Line-4 Distance Protection Audit - check list No. Relay configuration - Line distance protection 1 Name and length of line 2 Series compensated? Y/N 3 Is this a cable feeder / line feeder/ composite feeder (line+cable)? 4 Which mode of communication is used (PLCC/ OPGW) 5 Details of composite type numerical relays Relay make and model Whether the relay is functional?? Date of testing Mention all the active protections Details of type relays Main-1 Relay Main-2 Relay Mode of Carrier aided scheme for 21 ( If POR scheme is used whether Current Reversal Guard Logic implemented?) Carrier aided scheme active for 67/67N Mode of Carrier aided scheme for 67/67N For 87L which scheme is used? (Pilot wire communication/ digital communication) Power swing/out of step active? SOTF active? Auto Reclose (79) active? Breaker failure active Load Encroachment active Stub Protection active Fault locator active? Disturbance Recorder active? 6 Relay Connected to Trip Coil-1/ Trip Coil-2 or both? 7 Feed from DC supply 1 / DC Supply 2 8 Connected to Dedicated CT core? Define CT core no. to which the relay is connected 9 CT ratio selected 10 VT ratio selected for ex: Siemens 7SA522 21/87L/ Accelerated Under reach/ Permissive Under reach/intertripping Under reach/ Permissive Overreach/ Blocking Over reach/ Phase Comparison Protection (for PLCC) Directional Comparison Protection (Permissive)/ Directional Comparison Protection (Blocking) Other Relays (Back-up relays, DR, FL etc.) Southern Region - (Station Name) 23/58 Page 23 of 58

400 kv (Line Name) Line-4 Distance Protection Audit - check list No. Relay configuration - Line distance protection Details of separate relays if applicable Relay 1 make and model Functions available in Relay 1 Relay 1 Functional Relay 2 make and model Functions available in Relay 2 Relay 2 Functional 11 Relay 3 make and model Functions available in Relay 3 Relay 3 Functional Relay 4 make and model Functions available in Relay 4 Relay 4 Functional 12 VT Fuse failure protection present & used to block distance function operation? 13 Overvoltage protection available Functional with two stage protection 14 Are all the auxiliary relays (94) considered for Line protection (Main-1/ Main-2/ Backup) provided with supervision relays (74/ 94)? 15 Do the Line Protection protection panels have supervision relays for DC supply-1 & DC supply-2 (74/DC-1 & 74/DC-2)? Southern Region - (Station Name) 24/58 Page 24 of 58

220 kv (Line Name) Line-1 Distance Protection Audit - check list No. Relay configuration - Line distance protection 1 Name and length of line 2 Series compensated? Y/N 3 Is this a cable feeder / line feeder/ composite feeder (line+cable)? 4 Which mode of communication is used (PLCC/ OPGW) 5 Details of composite type numerical relays Relay make and model Whether the relay is functional?? Date of testing Mention all the active protections Details of type relays Main-1 Relay Main-2 Relay Mode of Carrier aided scheme for 21 ( If POR scheme is used whether Current Reversal Guard Logic implemented?) Carrier aided scheme active for 67/67N Mode of Carrier aided scheme for 67/67N For 87L which scheme is used? (Pilot wire communication/ digital communication) Power swing/out of step active? SOTF active? Auto Reclose (79) active? Breaker failure active Load Encroachment active Stub Protection active Fault locator active? Disturbance Recorder active? 6 Relay Connected to Trip Coil-1/ Trip Coil-2 or both? 7 Feed from DC supply 1 / DC Supply 2 8 Connected to Dedicated CT core? Define CT core no. to which the relay is connected 9 CT ratio selected 10 VT ratio selected for ex: Siemens 7SA522 21/87L/ Accelerated Under reach/ Permissive Under reach/intertripping Under reach/ Permissive Overreach/ Blocking Over reach/ Phase Comparison Protection (for PLCC) Directional Comparison Protection (Permissive)/ Directional Comparison Protection (Blocking) Other Relays (Back-up relays, DR, FL etc.) Southern Region - (Station Name) 25/58 Page 25 of 58

220 kv (Line Name) Line-1 Distance Protection Audit - check list No. Relay configuration - Line distance protection Details of separate relays if applicable Relay 1 make and model Functions available in Relay 1 Relay 1 Functional Relay 2 make and model Functions available in Relay 2 Relay 2 Functional 11 Relay 3 make and model Functions available in Relay 3 Relay 3 Functional Relay 4 make and model Functions available in Relay 4 Relay 4 Functional 12 VT Fuse failure protection present & used to block distance function operation? 13 Overvoltage protection available Functional with two stage protection 14 Are all the auxiliary relays (94) considered for Line protection (Main-1/ Main-2/ Backup) provided with supervision relays (74/ 94)? 15 Do the Line Protection protection panels have supervision relays for DC supply-1 & DC supply-2 (74/DC-1 & 74/DC-2)? Southern Region - (Station Name) 26/58 Page 26 of 58

220 kv (Line Name) Line-2 Distance Protection Audit - check list No. Relay configuration - Line distance protection 1 Name and length of line 2 Series compensated? Y/N 3 Is this a cable feeder / line feeder/ composite feeder (line+cable)? 4 Which mode of communication is used (PLCC/ OPGW) 5 Details of composite type numerical relays Relay make and model Whether the relay is functional?? Date of testing Mention all the active protections Details of type relays Main-1 Relay Main-2 Relay Mode of Carrier aided scheme for 21 ( If POR scheme is used whether Current Reversal Guard Logic implemented?) Carrier aided scheme active for 67/67N Mode of Carrier aided scheme for 67/67N For 87L which scheme is used? (Pilot wire communication/ digital communication) Power swing/out of step active? SOTF active? Auto Reclose (79) active? Breaker failure active Load Encroachment active Stub Protection active Fault locator active? Disturbance Recorder active? 6 Relay Connected to Trip Coil-1/ Trip Coil-2 or both? 7 Feed from DC supply 1 / DC Supply 2 8 Connected to Dedicated CT core? Define CT core no. to which the relay is connected 9 CT ratio selected 10 VT ratio selected for ex: Siemens 7SA522 21/87L/ Accelerated Under reach/ Permissive Under reach/intertripping Under reach/ Permissive Overreach/ Blocking Over reach/ Phase Comparison Protection (for PLCC) Directional Comparison Protection (Permissive)/ Directional Comparison Protection (Blocking) Other Relays (Back-up relays, DR, FL etc.) Southern Region - (Station Name) 27/58 Page 27 of 58

220 kv (Line Name) Line-2 Distance Protection Audit - check list No. Relay configuration - Line distance protection Details of separate relays if applicable Relay 1 make and model Functions available in Relay 1 Relay 1 Functional Relay 2 make and model Functions available in Relay 2 Relay 2 Functional 11 Relay 3 make and model Functions available in Relay 3 Relay 3 Functional Relay 4 make and model Functions available in Relay 4 Relay 4 Functional 12 VT Fuse failure protection present & used to block distance function operation? 13 Overvoltage protection available Functional with two stage protection 14 Are all the auxiliary relays (94) considered for Line protection (Main-1/ Main-2/ Backup) provided with supervision relays (74/ 94)? 15 Do the Line Protection protection panels have supervision relays for DC supply-1 & DC supply-2 (74/DC-1 & 74/DC-2)? Southern Region - (Station Name) 28/58 Page 28 of 58

220 kv (Line Name) Line-3 Distance Protection Audit - check list No. Relay configuration - Line distance protection 1 Name and length of line 2 Series compensated? Y/N 3 Is this a cable feeder / line feeder/ composite feeder (line+cable)? 4 Which mode of communication is used (PLCC/ OPGW) 5 Details of composite type numerical relays Relay make and model Whether the relay is functional?? Date of testing Mention all the active protections Details of type relays Main-1 Relay Main-2 Relay Mode of Carrier aided scheme for 21 ( If POR scheme is used whether Current Reversal Guard Logic implemented?) Carrier aided scheme active for 67/67N Mode of Carrier aided scheme for 67/67N For 87L which scheme is used? (Pilot wire communication/ digital communication) Power swing/out of step active? SOTF active? Auto Reclose (79) active? Breaker failure active Load Encroachment active Stub Protection active Fault locator active? Disturbance Recorder active? 6 Relay Connected to Trip Coil-1/ Trip Coil-2 or both? 7 Feed from DC supply 1 / DC Supply 2 8 Connected to Dedicated CT core? Define CT core no. to which the relay is connected 9 CT ratio selected 10 VT ratio selected for ex: Siemens 7SA522 21/87L/ Accelerated Under reach/ Permissive Under reach/intertripping Under reach/ Permissive Overreach/ Blocking Over reach/ Phase Comparison Protection (for PLCC) Directional Comparison Protection (Permissive)/ Directional Comparison Protection (Blocking) Other Relays (Back-up relays, DR, FL etc.) Southern Region - (Station Name) 29/58 Page 29 of 58

220 kv (Line Name) Line-3 Distance Protection Audit - check list No. Relay configuration - Line distance protection Details of separate relays if applicable Relay 1 make and model Functions available in Relay 1 Relay 1 Functional Relay 2 make and model Functions available in Relay 2 Relay 2 Functional 11 Relay 3 make and model Functions available in Relay 3 Relay 3 Functional Relay 4 make and model Functions available in Relay 4 Relay 4 Functional 12 VT Fuse failure protection present & used to block distance function operation? 13 Overvoltage protection available Functional with two stage protection 14 Are all the auxiliary relays (94) considered for Line protection (Main-1/ Main-2/ Backup) provided with supervision relays (74/ 94)? 15 Do the Line Protection protection panels have supervision relays for DC supply-1 & DC supply-2 (74/DC-1 & 74/DC-2)? Southern Region - (Station Name) 30/58 Page 30 of 58

220 kv (Line Name) Line-4 Distance Protection Audit - check list No. Relay configuration - Line distance protection 1 Name and length of line 2 Series compensated? Y/N 3 Is this a cable feeder / line feeder/ composite feeder (line+cable)? 4 Which mode of communication is used (PLCC/ OPGW) 5 Details of composite type numerical relays Relay make and model Whether the relay is functional?? Date of testing Mention all the active protections Details of type relays Main-1 Relay Main-2 Relay Mode of Carrier aided scheme for 21 ( If POR scheme is used whether Current Reversal Guard Logic implemented?) Carrier aided scheme active for 67/67N Mode of Carrier aided scheme for 67/67N For 87L which scheme is used? (Pilot wire communication/ digital communication) Power swing/out of step active? SOTF active? Auto Reclose (79) active? Breaker failure active Load Encroachment active Stub Protection active Fault locator active? Disturbance Recorder active? 6 Relay Connected to Trip Coil-1/ Trip Coil-2 or both? 7 Feed from DC supply 1 / DC Supply 2 8 Connected to Dedicated CT core? Define CT core no. to which the relay is connected 9 CT ratio selected 10 VT ratio selected for ex: Siemens 7SA522 21/87L/ Accelerated Under reach/ Permissive Under reach/intertripping Under reach/ Permissive Overreach/ Blocking Over reach/ Phase Comparison Protection (for PLCC) Directional Comparison Protection (Permissive)/ Directional Comparison Protection (Blocking) Other Relays (Back-up relays, DR, FL etc.) Southern Region - (Station Name) 31/58 Page 31 of 58

220 kv (Line Name) Line-4 Distance Protection Audit - check list No. Relay configuration - Line distance protection Details of separate relays if applicable Relay 1 make and model Functions available in Relay 1 Relay 1 Functional Relay 2 make and model Functions available in Relay 2 Relay 2 Functional 11 Relay 3 make and model Functions available in Relay 3 Relay 3 Functional Relay 4 make and model Functions available in Relay 4 Relay 4 Functional 12 VT Fuse failure protection present & used to block distance function operation? 13 Overvoltage protection available Functional with two stage protection 14 Are all the auxiliary relays (94) considered for Line protection (Main-1/ Main-2/ Backup) provided with supervision relays (74/ 94)? 15 Do the Line Protection protection panels have supervision relays for DC supply-1 & DC supply-2 (74/DC-1 & 74/DC-2)? Southern Region - (Station Name) 32/58 Page 32 of 58

HV/ LV kv ICT-1 Transformer Protection Audit - check list No Relay configuration - Power Transformers protections 1 Name, voltage, power 2 Are used 2 groups of protections (Group A and Group B) for transformer protection? 3 Are Group A and Group B protections connected to separate DC sources for power transformers? 4 Do the Group A and Group B protections have separate lockout relays? Details of type relays Details of composite type numerical relays Relay make and model Main Back up A B C D Other Protections Whether the relay is functional? Date of testing Mention all the active protections Differential protection REF protection 5 Back-up directional O/C +E/F protection Overfluxing protection Connected to Trip Coil 1/Trip Coil2/Both Feed from DC supply 1/DC supply2 Breaker failure active Disturbance Report active Connected to dedicated CT core? Define CT core no. to which the relay is connected CT ratio selected Is CT supervision enabled or not in case of Transformer differential protection? 6 Are all the Lock out relays (86) considered for Transformer protection provided with supervision relays (74/86)? 7 Do the Transformer protection panels have supervision relays for DC supply-1 & DC supply-2 (74/DC-1 & 74/DC-2)? 8 OTI working 9 WTI working 10 Buchholtz working 11 PRD/ PRV working 12 LA rating HV side 13 LA rating IV side Southern Region - (Station Name) 33/58 Page 33 of 58

HV/ LV kv ICT-2 Transformer Protection Audit - check list No Relay configuration - Power Transformers protections 1 Name, voltage, power 2 Are used 2 groups of protections (Group A and Group B) for transformer protection? 3 Are Group A and Group B protections connected to separate DC sources for power transformers? 4 Do the Group A and Group B protections have separate lockout relays? Details of type relays Details of composite type numerical relays Relay make and model Main Back up A B C D Other Protections Whether the relay is functional? Date of testing Mention all the active protections Differential protection REF protection 5 Back-up directional O/C +E/F protection Overfluxing protection Connected to Trip Coil 1/Trip Coil2/Both Feed from DC supply 1/DC supply2 Breaker failure active Disturbance Report active Connected to dedicated CT core? Define CT core no. to which the relay is connected CT ratio selected Is CT supervision enabled or not in case of Transformer differential protection? 6 Are all the Lock out relays (86) considered for Transformer protection provided with supervision relays (74/86)? 7 Do the Transformer protection panels have supervision relays for DC supply-1 & DC supply-2 (74/DC-1 & 74/DC-2)? 8 OTI working 9 WTI working 10 Buchholtz working 11 PRD/ PRV working 12 LA rating HV side 13 LA rating IV side Southern Region - (Station Name) 34/58 Page 34 of 58

765 kv Bus Reactor Protection Audit - check list No 1 Name,Voltage,Power Relay configuration - Shunt reactor protections 2 Are used 2 groups of protections (Group A and Group B) for shunt reactors protection? 3 Are Group A and Group B protections connected to separate DC sources for shunt reactors? 4 Do the Group A and Group B protections have separate lockout relays? Details of type relays Details of composite type numerical relays Relay make and model Main Back up A B C D Other Protections Whether the relay is functional? Date of testing Mention all the active protections Differential protection REF protection 5 Back-up directional O/C +E/F protection Overfluxing protection Connected to Trip Coil1 / Trip Coil2 / Both Feed from DC supply 1/DC supply2 Breaker failure active 6 7 Disturbance Recorder active Connected to dedicated CT core? Define CT core no.to which the relay is connected CT ratio selected Is CT supervision enabled or not in case of Reactor differential protection? Are all the Lock out relays (86) considered for Reactor protection provided with supervision relays (74/ 86)? Do the Reactor protection panels have supervision relays for DC supply-1 & DC supply-2 (74/DC-1 & 74/DC-2)? 8 OTI indications working 9 WTI indications working 10 Bucholtz working 11 PRD/ PRV working 12 LA rating HV side Southern Region - (Station Name) 35/58 Page 35 of 58

400 kv Bus Reactor Protection Audit - check list No Relay configuration - Power Transformers protections 1 Name, voltage, power 2 Are used 2 groups of protections (Group A and Group B) for transformer protection? 3 Are Group A and Group B protections connected to separate DC sources for power transformers? 4 Do the Group A and Group B protections have separate lockout relays? Details of type relays Details of composite type numerical relays Relay make and model Main Back up A B C D Other Protections Whether the relay is functional? Date of testing Mention all the active protections Differential protection REF protection 5 Back-up directional O/C +E/F protection Overfluxing protection Connected to Trip Coil 1/Trip Coil2/Both Feed from DC supply 1/DC supply2 Breaker failure active Disturbance Report active Connected to dedicated CT core? Define CT core no. to which the relay is connected CT ratio selected Is CT supervision enabled or not in case of Transformer differential protection? 6 Are all the Lock out relays (86) considered for Transformer protection provided with supervision relays (74/86)? 7 Do the Transformer protection panels have supervision relays for DC supply-1 & DC supply-2 (74/DC-1 & 74/DC-2)? 8 OTI working 9 WTI working 10 Buchholtz working 11 PRD/ PRV working 12 LA rating HV side Southern Region - (Station Name) 36/58 Page 36 of 58

765 kv Line Reactor (Line Name) Protection audit - check list No Relay configuration - Power Transformers protections 1 Name, voltage, power 2 Are used 2 groups of protections (Group A and Group B) for transformer protection? 3 Are Group A and Group B protections connected to separate DC sources for power transformers? 4 Do the Group A and Group B protections have separate lockout relays? 5 Details of composite type numerical relays Relay make and model Whether the relay is functional? Date of testing Mention all the active protections Differential protection REF protection Back-up directional O/C +E/F protection Overfluxing protection Connected to Trip Coil 1/Trip Coil2/Both Feed from DC supply 1/DC supply2 Breaker failure active Disturbance Report active Connected to dedicated CT core? Define CT core no. to which the relay is connected CT ratio selected Details of type relays Main Back up A B C D Other Protections Is CT supervision enabled or not in case of Transformer differential protection? 6 Are all the Lock out relays (86) considered for Transformer protection provided with supervision relays (74/86)? 7 Do the Transformer protection panels have supervision relays for DC supply-1 & DC supply-2 (74/DC-1 & 74/DC-2)? 8 OTI indications working 9 WTI indications working 10 Bucholtz working 11 PRD/ PRV working 12 LA rating HV side Southern Region - (Station Name) 37/58 Page 37 of 58