ABB RELION RET670, Commissioning Manual, Page: 233 / 328

11.8.1.1 Built-in overcurrent feature (non-directional)
Procedure
1. Go to Main menu/Test/Function test modes/Multipurpose protection/
GeneralCurrentVoltage(GAPC)/CVGAPC:x and make sure that CVGAPC to be
tested is unblocked and other functions that might disturb the evaluation of the test
are blocked.
2. Connect the test set for injection of three-phase currents to the appropriate current
terminals of the IED.
3. Inject current(s) in a way that relevant measured current (according to setting
parameter
CurrentInput ) is created from the test set. Increase the current(s) until the
low set stage trips and check against the set trip value.
4. Decrease the current slowly and check the reset value.
5. Block high set stage if the injection current will activate the high set stage when
testing the low set stage according to below.
6. Connect a TRIP output contact to the timer.
7. Set the current to 200% of the trip value of low set stage, switch on the current and
check the time delay.
For inverse time curves, check the trip time at a current equal to 110% of the trip
current at
t_MinTripDelay .
8. Check that TRIP and PICKUP contacts trip according to the configuration logic.
9. Release the blocking of the high set stage and check the trip and reset value and the
time delay for the high set stage in the same way as for the low set stage.
10. Finally check that PICKUP and TRIP information is stored in the event menu.
Information on how to use the event menu is found in the operator's
manual.
11.8.1.2 Overcurrent feature with current restraint
The current restraining value has also to be measured or calculated and the influence on
the operation has to be calculated when the testing of the trip value is done.
Procedure
1. Trip value measurement
The current restraining value has also to be measured or calculated and the influence
on the operation has to be calculated when the testing of the trip value is done.
1MRK 504 165-UUS -
Section 11
Testing functionality by secondary injection
Transformer protection RET670 2.2 ANSI 227
Commissioning manual