Method Statement MV Panel Complete
Method Statement MV Panel Complete
Method Statement MV Panel Complete
1) VISUAL INSPECTION
2) WIRING AND FERRULING CHECK
3) BUS CONTINUITY, PHASING AND CONTACT RESISTANCE TEST
4) CURRENT TRANSFORMER CHECKS
2.1 Ensure the numbers on the ferrules are from left to right beginning at the
terminal block i.e. at the end of the wire and from bottom to top.
2.2 The wire nos. should be checked against the wiring table and the schematic
drawing.
At the CB Closed
• Connect the phases Y, B to ground and apply the test voltage
between phase R and ground.
• Connect the phases B, R to ground and apply the test voltage
between phase Y and ground.
• Connect the phases R, Y to ground and apply the test voltage
between phase B and ground.
• Record the corresponding Insulation Resistance readings.
At the CB Open
• Connect the phases R, Y, B Cable side to the ground.
• Connect the phases R, Y, B Bus side to the test set.
• Record the corresponding Insulation Resistance readings.
At the CB Closed
• Connect the phases Y, B to ground and apply the test voltage
between phase R and ground.
• Connect the phases B, R to ground and apply the test voltage
between phase Y and ground.
• Connect the phases R, Y to ground and apply the test voltage
between phase B and ground.
• Record the corresponding leakage current readings.
At the CB Open
• Connect the phases R, Y, B Cable side to the ground.
• Connect the phases R, Y, B Bus side to the test set.
• Record the corresponding leakage current readings.
7.3.3 Insulation Resistance Test of All Low Voltage Wiring and Cabling At
500 V DC.
• Connect all the wires together (+ve and –ve) or (L and N) and apply
the test voltage between the wires and ground.
• Record the corresponding Insulation Resistance readings.
Metering calibration shall be tested via front panel mounted test facilities.
Maximum demand indicator (MDI) meters shall be tested at 10% and 100%
of full scale.
Current and voltage metering and transducers calibration shall be tested at
0, 25, 50, 100% of scale.
Watt and VAR metering and transducers calibration shall be tested at (+/-
when bi-directional) 0, 25, 50,100% of rated load and with rated voltage
and current at angles of 0, 45,180, 225, 270 and 315 degrees.
KWH and KVARH metering calibration shall be tested at 10% and 100% of
rated current at angles of 0, 45, 90, 180, 225, 270 and 315 degrees.
Power Factor metering and transducers calibration shall be tested at rated
voltage and at 50% lead, unity, 50% lag power factors at 10, 50 and 100%
rated current.
Notes:
1. Testing Engineer should provide the commissioning manuals and have the
detailed understanding for testing and commissioning procedure.
2. All outputs / indications to be tested.
3. Initial tests of new protective relays must include operating characteristics
checks for a representative range of available settings with Company approved
computer operated test equipment running routines developed for the specific
relay and test set involved.
4. Relay auxiliary devices such as external resistors, metrosils, etc. to be tested to
conform to required ratings and manufacturer’s information.
5. Final calibration test of all protective relays must be carried out on approved
settings, by secondary injection at the front panel mounted test facilities.
6. Auxiliary and tripping relay testing shall include,
7. Pickup and dropout voltage, verification of all contacts.
8. Operation timing at 80% and 100% nominal voltage.
9. Time delay relays shall be tested at 0%, set point and 100% delay.
10. Use of red and green tags for tested relays, meters, etc.
11. All the relays and meters, which have been tested and found O.K., must have
green tags.
12. The relays and meters found defective during tests should be tagged out.
9.1 Over Current Relay
11.3 Insulation Resistance Test of All Low Voltage Wiring and Cabling At
500 V DC.
• Connect all the wires together (+ve and –ve) or (L and N) and apply
the test voltage between the wires and ground.
• Record the corresponding Insulation Resistance readings
12. FUNCTIONAL CHECK