Electrical Testing and Commissioning Handbook

For Field Commissioning Staff

The interconnection of the electrical equipment and the equipment itself determines the dependability of any system. This handbook offers instructions for testing electrical systems according to National grid standards. Presumably, the extensive and thorough individual testing of the equipment has finished before the system’s commissioning started.

Nonetheless, usually the original proposal for the procurement of the equipment provides generic testing protocols for the components of the systems specified in this commissioning handbook. Apart from the advised testing below, one should follow the standards set by the equipment maker.

Every electrical system has several components, although some tests are universal throughout the equipment.

Based on the requirements and recommendation of international standards which shall be followed in strict norms as per the drawings, operation and maintenance manuals supplied by the Equipment manufacturer, these general procedures & norms in detail for accepting the equipment for their healthiness as per the specific component check, inspection and test are compiled in this manual.

This will act as a guide for the field commissioning staff to apply rigorous standards and method of testing that the contractor intends to follow per SEC transmission Construction Standards.

This handbook is meant to enable the commissioning personnel to efficiently complete pre-commissioning activities according to SEC Standard and specification before the equipment is brought to service condition.

Handbook Contents:

GIS and Switchgear:

1. GIS EHV & HV Circuit Breaker Tests
2. GIS EHV & HV Disconnect Switch Tests
3. HV and Partial Discharge test on GIS Switchgear
4. GIS Circuit Breaker Pole Discrepancy Scheme Check
5. 13.8kV Switchgear Circuit Breaker Tests
6. 13.8kV Switchgear Earthing Switch Tests
7. 13.8kV Busbar Switchgear Tests
8. 13.8kV Switchgear HV Tests
9. Switchgear Ring Main Unit Tests
10. Surge Arrester Tests
11. Circuit Breaker Mechanism Tests

Current Transformer (CT):

1. CT Insulation testing
2. CT Turns Ratio Test
3. CT Excitation (Kneepoint)
4. CT Winding Resistance Test
5. CT Voltage Withstand Test
6. CT Polarity Check

Voltage Transformer (VT):

1. VT Insulation testing
2. VT Turns Ratio Test
3. VT Excitation (Knee-point)
4. VT Winding Resistance Test
5. VT Voltage Withstand Test

Power Transformer:

1. Measurement of Winding Insulation Resistance
2. Measurement of Core and Frame Insulation at 1kV DC
3. Winding Resistance Test
4. Excitation Current(No Load) Test
5. Short Circuit(%Z) Test
6. Zero Sequence Impedance Test
7. Turns Ratio Test
8. Magnetic Balance Test
9. Vector Group Test
10. Tan Delta Test
11. Oil Dielectric Breakdown Test
12. Calibration of Oil & Winding Temperature Sensors
13. Cooling Fan Tests
14. Supervision Equipment Functional Checks
15. On-Load Tap Changer MDU Check & Current Consumption
16. Frequency Response Analysis

Grounding Transformer:

1. GT Measurement of Winding Insulation Resistance
2. Measurement of Core and Frame Insulation at 1kV DC
3. Winding Resistance Test
4. Calibration of Oil and Winding Temperature Sensors
5. Tan Delta Test
6. Oil Dielectric Breakdown Test
7. Impedance Measurement
8. Supervision Equipment Functional Checks
9. Cooling Fan Tests

Shunt Reactor:

1. Measurement of Winding Insulation Resistance
2. Measurement of Core and Frame Insulation at 1kV DC
3. Winding Resistance Test
4. Calibration of Oil and Winding Temperature Sensors
5. Tan Delta Test
6. Oil Dielectric Breakdown Test
7. Impedance Measurement
8. Supervision Equipment Functional Checks
9. Cooling Fan Tests

Capacitor Bank Testing & Commissioning

Static VAR Compensation System Commissioning

Automatic Voltage Regulator(AVR):

1. AVR – Control Panel Scheme Check and Function
2. AVR – Relay Configuration, Bandwidth and Timer Check
3. AVR – Relay Blocking Protection Function Tests
4. AVR – Digital Voltmeter

Battery Bank and Battery Charger:

1. Battery Bank and Unit Testing
2. Battery Charger Testing
3. Battery Charger Testing – Functional Checks

AC Distribution Panel (ACDB):

1. ACDB Panels – MCB and MCCB Tests
2. ACDB Panels – Auxiliary Relays and Timers Test
3. ACDB Panels – Other Component Test
4. ACDB Panels – LV Automatic Transfer Switching Scheme Tests
5. ACDB Panels – LV Automatic Transfer Switch Phase sequence Check and Phasing test

DC Distribution Panel (DCDB):

1. DCDB Panels – MCB and MCCB Tests
2. DCDB Panels – Auxiliary Relays and Timers Test
3. DCDB Panels – Other Component Test

Transmission line and Power Cables:

1. Phase Checking for Conductor & Sheath Test(@ 10kV DC)
2. Capacitance and Insulation Resistance Measurement
3. Conductivity and Continuity Test for Transmission Line Conductors
4. Phase conductor insulation resistance test for Transmission Line
5. Susceptance Test for Transmission Line
6. Verification of Cross Bonding Test At Link Boxes
7. Power Cable High Voltage Test
8. Phase Checking for Transmission Line Conductors
9. DC Conductor Resistance Earth Resistance Measurement
10. SVL Insulation Resistance and Contact Resistance Test on Link Boxes
11. Zero, Positive, & Negative Sequence Impedance Test
12. Zero Sequence and Positive Sequence Impedance Tests for Transmission Lines

Meters:

1. Testing & Commissioning of AMI
2. Testing & Commissioning of Analog or Digital Meters

Protection Relays:

1. Line & Cable Differential Protection Relay (87L_87C) Commissioning
2. Circuit Breaker Fail (CBF) Protection Relay (50_62) Commissioning
3. Bus Bar Protection Stability & Sensitivity Test
4. Transformer Differential Protection relay (87T) Commissioning and Testing
5. Transformer Differential Protection Stability & Sensitivity Test
6. Reactor Differential Protection relay (87R) Commissioning and Testing
7. Reactor Differential Protection Stability & Sensitivity Test
8. Directional Negative Phase Sequence Overcurrent Relay (67Q) Test
9. Directional Overcurrent and Earth Fault Protection relay (67_67N) Commissioning
10. Over and Under Voltage Relay Test
11. Restricted Earth Fault Protection Stability and Sensitivity Test
12. Distance, Impedance Protection Relay (21) Commissioning
13. Overcurrent, Undercurrent and Earth Fault Relay Test
14. Over and Under Frequency Relay Test
15. Trip Circuit Supervision Relay
16. Synchronism Check (25) Relay Test
17. Lock-out Relay(86) Test
18. Auto-Recloser(79) Test
19. CT Supervision Relay
20. High Impedance Busbar Relay Test
21. Capacitor Bank Protection Relay Test
22. High Impedance Differential(87TEE) Relay Test
23. Trip Coil Relay(94) Test
24. End to End

Scheme Check:

1. Scheme Check – General Instructions
2. Automatic Bus Transfer System Scheme Check (ABTS)
3. Automatic Capacitor Control Scheme Check (ACCS)
4. Equipment Scheme

Substation Automation System (SAS):

1. Prerequisite Work Instruction to start SAS Commissioning
2. SAS Fiber Optic Cable Testing
3. SAS Function Check of All Peripheral Devices
4. SAS Measurement Testing
5. SAS Engineering Workstation (EWS) Testing
6. SAS Ethernet Switches Testing
7. SAS Redundancy Testing
8. SAS Gateways Testing
9. SAS GPS Testing
10. SAS IED’s Testing
11. Maintenance Laptop Testing
12. Operating Workstation Testing
13. SAS Panels Inspection & Testing
14. SAS Servers Testing
15. SAS Function Testing
16. SAS Overall Interlocking Testing
17. Final Trip Test
18. Relays Final Settings Review for EHV, HV, MV & SVC
19. Normalization Before Energization
20. Energization

Recommended Reading – Standard Operating Procedures (SOPs) for GIS Substations You MUST Fully Respect

Standard Operating Procedures (SOPs) for GIS Substations You MUST Fully Respect