ABB Relion REQ650, Руководство по применению

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Table 19: Dependencies between parameters RetripMode and FunctionMode
RetripMode FunctionMode
Description
Retrip Off N/A The re-trip function is not
activated
CB Pos Check Current A phase current must be larger
than the operate level to allow
re-trip
Contact
Re-trip is done when circuit
breaker is closed (breaker
position is used) and a long
duration of a trip signal indicates
breaker failure
Current&Contact
Both methods are used
No CB Pos Check Current
Re-trip is done without check of
breaker position
Contact
Re-trip is done without check of
breaker position
Current&Contact
Both methods are used
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 and 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
of 4 . The current setting should be chosen in accordance to the setting of the sensitive
earth fault protection. The setting can be given within the range 2 – 200 % of IBase .
Section 6
1MRK 505 291-UEN A
Current protection
138
Application manual