Prepare the IED for verification of settings outlined in section 1 “Overview” and section
2 “Preparing for test” in this chapter.
Current variation local criteria
Procedure
1. Set Operation to Enabled.
2. Connect the test set for three phase current injection to the appropriate IED
terminals.
3. Inject symmetrical phase currents equal to half the rated current
4. Increase the injected current in phase A slowly by more than the set Pick Up ICV. No
signal shall be activated.
5. Decrease the injected current in phase A to half the rated current.
6. Increase the injected current in phase A in a step by more than the set Pick Up ICV.
Pickup shall be activated.
Undervoltage criteria
Procedure
1. Connect the test set for three phase current injection and three phase voltage to the
appropriate IED terminals.
2. Inject symmetrical phase voltages equal to the rated voltage.
3. Decrease the injected voltage in phase A and note the operated value (pickup value)
of the function.
4. Increase the voltage slowly and note the reset value.
5. Connect a trip output contact to a timer.
6. Reduce the injected voltage stepwise to 90 % of the trip level, and check the time
delay.
7. Repeat points 3– 6 for phases B and C.
8. Inject symmetrical phase voltages equal to the rated voltage.
9. Decrease the injected phase-phase voltage A-B and note the operated value (start
value) of the function.
10. Increase the voltage slowly and note the reset value.
11. Connect a trip output contact to a timer.
12. Reduce the injected voltage stepwise to 90 % of the trip level, and check the time
delay.
13. Repeat points 9 – 12 for phases B-C and C-A.
Zero sequence overcurrent criteria
Procedure
1MRK 504 165-UUS - Section 11
Testing functionality by secondary injection
Transformer protection RET670 2.2 ANSI 111
Commissioning manual
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