ABB RELION RET670, Commissioning Manual, Page: 199 / 328

Checking the case without re-trip,
RetripMode = Retrip Off
1. Set RetripMode = Retrip Off .
2. Apply the fault condition, including initiation of CCRBRF (50BF), well above the
set current value.
3. Verify that no re-trip, but back-up trip is achieved after set time.
4. Disconnect AC and BFI_3P input signals.
Checking the re-trip with current check,
RetripMode = CB Pos Check
1. Set RetripMode = CB Pos Check .
2. Apply the fault condition, including initiation of CCRBRF (50BF), well above the
set current value.
3. Verify that re-trip is achieved after set time t1 and back-up trip after time t2 .
4. Apply the fault condition, including initiation of CCRBRF (50BF), with current
below set current value.
5. Verify that no re-trip and no back-up trip are obtained.
6. Disconnect AC and BFI_3P input signals.
Checking re-trip without current check
1. Set RetripMode = No CBPos Check .
2. Apply the fault condition, including initiation of CCRBRF (50BF), well above the
set current value.
3. Verify that re-trip is achieved after the set time t1 , and the back-up trip after time t2 .
4. Apply the fault condition, including initiation of CCRBRF (50BF), with current
below set current value.
5. Verify that re-trip is achieved after set time t1 , but no back-up trip is obtained.
6. Disconnect AC and BFI_3P input signals.
11.5.8.5 Verifying the back-up trip mode
In the cases below it is assumed that FunctionMode = Current is selected.
Checking that back-up tripping is not achieved at normal CB tripping
Use the actual tripping modes. The case below applies to re-trip with current check.
1. Apply the fault condition, including initiation of CCRBRF (50BF), with phase
current well above set value
Pickup_PH .
2. Interrupt the current, with a margin before back-up trip time, t2 . It may be made at
issue of re-trip command.
3. Check that re-trip is achieved, if selected, but no back-up trip is obtained.
4. Disconnect AC and BFI_3P input signals.
1MRK 504 165-UUS -
Section 11
Testing functionality by secondary injection
Transformer protection RET670 2.2 ANSI 193
Commissioning manual