ABB RELION RET670, Commissioning Manual, Page: 231 / 328

Extended testing
1. The test above can be repeated to check the time to reset.
Verification of the low voltage magnitude blocking
1. Check that the settings in the IED are appropriate, for example the PUFrequency and
the tDelay .
2. Supply the IED with three-phase voltages at their rated values.
3. Slowly decrease the magnitude of the applied voltage, until the BLKDMAGN signal
appears.
4. Note the voltage magnitude value and compare it with the set value.
5. Slowly increase the frequency of the applied voltage, to a value above
PUFrequency .
6. Check that the PICKUP signal does not appear.
7. Wait for a time corresponding to tDelay , make sure that the TRIP signal does not
appear.
11.7.2.2 Completing the test
Continue to test another function or end the test by changing the TESTMODE setting to
Disabled . Restore connections and settings to their original values, if they were changed
for testing purposes.
11.7.3 Rate-of-change frequency protection SAPFRC (81)
Prepare the IED for verification of settings outlined in Section "Preparing the IED to
verify settings" .
11.7.3.1 Verifying the settings
PICKUP value and time delay to trip
1. Check that the settings in the IED are appropriate, especially the PICKUP value and
the definite time delay. Set
PickupFreqgrad , to a rather small negative value.
2. Supply the IED with three-phase voltages at their rated values.
3. Slowly decrease the frequency of the applied voltage, with an increasing rate-of-
change that finally exceeds the setting of
PickupFreqgrad , and check that the
PICKUP signal appears.
4. Note the trip value and compare it with the set value.
5. Increase the frequency to rated operating conditions, and zero rate-of-change.
1MRK 504 165-UUS -
Section 11
Testing functionality by secondary injection
Transformer protection RET670 2.2 ANSI 225
Commissioning manual