Breaker failure protection, 3-phase activation and output (CCRBRF) will issue a
back-up trip command to adjacent circuit breakers in case of failure to trip of the
“normal” circuit breaker for the protected object. The detection of failure to break the
current through the breaker is made by means of current measurement or as detection
of remaining trip signal (unconditional).
CCRBRF can also give a re-trip. This means that a second trip signal is sent to the
protected circuit breaker. The re-trip function can be used to increase the probability
of operation of the breaker, or it can be used to avoid back-up trip of many breakers
in case of mistakes during relay maintenance and testing.
9.8.3 Setting guidelines
The parameters for Breaker failure protection 3-phase activation and output CCRBRF
are set via the local HMI or PCM600.
The following settings can be done for the breaker failure protection.
GlobalBaseSel: Selects the global base value group used by the function to define
IBase, UBase and SBase as applicable.
Operation: Off/On
FunctionMode This parameter can be set Current or Contact. This states the way the
detection of failure of the breaker is performed. In the mode current the current
measurement is used for the detection. In the mode Contact the long duration of
breaker position signal is used as indicator of failure of the breaker. The mode
Current/Contact means that both ways of detections are activated. Contact mode can
be usable in applications where the fault current through the circuit breaker is small.
This can be the case for some generator protection application (for example reverse
power protection) or in case of line ends with weak end infeed.
RetripMode: This setting states how the re-trip function shall operate. Retrip Off
means that the re-trip function is not activated. CB Pos Check (circuit breaker position
check) and Current means that a phase current must be larger than the operate level to
allow re-trip. CB Pos Check (circuit breaker position check) and Contact means re-trip
is done when circuit breaker is closed (breaker position is used). No CBPos Check
means re-trip is done without any check of breaker position.
1MRK 502 071-UEN - Section 9
Current protection
Generator protection REG670 2.2 IEC and Injection equipment REX060, REX061, REX062 371
Application manual
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