ABB REB650, Applications Manual

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Table 17: Dependencies between parameters RetripMode and FunctionMode
RetripMode FunctionMode
Description
Retrip Off N/A the re-trip function is not
activated
CB Pos Check Current re-trip is done if the phase
current is larger than the
operate level after re-trip time
has elapsed
Contact re-trip is done when auxiliary
contact position indicates that
breaker is still closed after re-
trip time has elapsed
Current/Contact
both methods according to
above are used but taken into
account also
I>BlkCont
No CBPos Check Current
re-trip is done without check of
current level
Contact
re-trip is done without check of
auxiliary contact position
Current/Contact
re-trip is done without check of
current level or auxiliary contact
position
BuTripMode : Back-up trip mode is given to state sufficient current criteria to detect
failure to break. For Current operation 2 out of 4 means that at least two currents,
of the three-phase currents and the residual current, shall be high to indicate
breaker failure.
1 out of 3 means that at least one current of the three-phase currents
shall be high to indicate breaker failure. 1 out of 4 means that at least one current of
the three-phase currents or the residual current shall be high to indicate breaker
failure. In most applications
1 out of 3 is sufficient. For Contact operation means
back-up trip is done when circuit breaker is closed (breaker position is used).
IP> : Current level for detection of breaker failure, set in % of IBase . This
parameter should be set so that faults with small fault current can be detected. The
setting can be chosen in accordance with the most sensitive protection function to
start the breaker failure protection. Typical setting is 10% of
IBase .
I>BlkCont : If any contact based detection of breaker failure is used, this function
can be blocked if any phase current is larger than this setting level. If the
FunctionMode is set Current/Contact breaker failure for high current faults are
safely detected by the current measurement function. To increase security the
contact based function should be disabled for high currents. The setting can be
given within the range 5 – 200% of
IBase .
IN> : Residual current level for detection of breaker failure set in % of IBase . In
high impedance earthed systems the residual current at phase- to-earth faults are
normally much smaller than the short circuit currents. In order to detect breaker
failure at single-phase-earth faults in these systems it is necessary to measure the
residual current separately. Also in effectively earthed systems the setting of the
earth-fault current protection can be chosen to relatively low current level. The
1MRK 505 388-UEN B
Section 7
Current protection
Busbar protection REB650 2.2 IEC 125
Application manual