ABB REL650 series, Applications Manual

Page: 240 / 516

One necessary component in the fault clearance system is the circuit breaker. It is from
practical and economical reason not feasible to duplicate the circuit breaker for the
protected component. Instead a breaker failure protection is used.
The Breaker failure protection, phase segregated activation and output (CSPRBRF 50BF)
issues a back-up trip command to adjacent circuit breakers in case of failure to trip of the
“normal” circuit breaker for the protected component. 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).
CSPRBRF (50BF) 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 test.
7.11.3 Setting guidelines
The parameters for Breaker failure protection, phase segregated activation and output
CSPRBRF (50BF) are set via the local HMI or PCM600.
The following settings can be done for the breaker failure protection, phase segregated
activation and output. Common base IED values for primary current (
IBase ), primary
voltage ( VBase ) and primary power (setting SBase ) are set in a Global base values for
settings function GBASVAL. Setting GlobalBaseSel is used to select a GBASVAL
function for reference of base values.
Operation : Disabled/ Enabled
FunctionMode : This parameter can be set Current/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 CB Pos Check means re-trip is done
without check of breaker position.
Section 7
1MRK 506 334-UUS A
Current protection
234
Application manual