11. Switch on the injection current and check that ALARM1 and ALARM2 contacts trip
at the set percentage level and that the trip time for tripping is in accordance with the
set Time Constant 1 (Tau1).
With setting Itr = 101%IBase1 and injection current 1.50 · IBase1, the trip time from
zero content in the memory shall be 0.60 · Time Constant 1 (Tau1).
12. Check that all trip and alarm contacts trip according to the configuration logic.
13. Switch off the injection current and check from the service menu readings of thermal
status and LOCKOUT that the lockout resets at the set percentage of heat content.
14. Activate the cooling input signal to switch over to base current IBase2.
Wait 5 minutes to empty the thermal memory and set Time Constant 2 (Tau2) in
accordance with the setting plan.
15. Test with injection current 1.50 · IBase2 the thermal alarm level, the trip time for
tripping and the lockout reset in the same way as described for stage IBase1.
16. Finally check that pickup and trip information is stored in the event menu.
11.5.7.2 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.
11.5.8 Breaker failure protection, phase segregated activation and
output CCRBRF (50BF)
Prepare the IED for verification of settings outlined in Section
"Preparing the IED to
verify settings".
The Breaker failure protection, 3-phase activation and output function CCRBRF (50BF)
should normally be tested in conjunction with some other function that provides an initiate
signal. An external BFI_3P signal can also be used.
To verify the settings in the most common back-up trip mode 1 out of 3, it is sufficient to
test phase-to-ground faults.
At mode 2 out of 4 the phase current setting, Pickup_PH can be checked by single-phase
injection where the return current is connected to the summated current input. The value
of residual (ground fault) current IN set lower than Pickup_PH is easiest checked in back-
up trip mode 1 out of 4.
11.5.8.1 Checking the phase current trip value,
Pickup_PH
The check of the Pickup_PH current level is best made in FunctionMode = Current and
BuTripMode = 1 out of 3 or 2 out of 4.
1MRK 504 165-UUS - Section 11
Testing functionality by secondary injection
Transformer protection RET670 2.2 ANSI 191
Commissioning manual
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