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Section 10
Testing functionality by secondary injection
10.4.6.4
10.4.6.5
78
Verifying the re-trip mode
Choose the mode below, which corresponds to the actual case.
In the cases below it is assumed that FunctionMode = Current is selected.
Checking the case without re-trip,
1.
Set RetripMode = Retrip Off.
2.
Apply the fault condition, including start of CCRBRF, well above the set current
value.
3.
Verify that no re-trip, but back-up trip is achieved after set time.
Checking the re-trip with current check,
1.
Set RetripMode = CB Pos Check.
2.
Apply the fault condition, including start of CCRBRF, 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 the start of CCRBRF, with the current
below the set current value.
5.
Verify that no re-trip, and no back-up trip is obtained.
Checking re-trip without current check
1.
Set RetripMode = No CBPos Check.
2.
Apply the fault condition, including start of CCRBRF, 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 start of CCRBRF, with current below set
current value.
5.
Verify that re-trip is achieved after set time t1, but no back-up trip is obtained.
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 start of CCRBRF, with phase current well
above set value IP>.
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.
RetripMode = Retrip Off
RetripMode = CB Pos Check
Transformer protection RET650 2.1 IEC
1MRK 504 160-UEN -
Commissioning manual
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