ABB Relion REG670, Руководство по применению

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Table 40: 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
BuTripMode is set 1 out
Section 9
1MRK 502 071-UEN -
Current protection
372 Generator protection REG670 2.2 IEC and Injection equipment REX060, REX061, REX062
Application manual