Figure. 5.4.7. - 31. Retrip and CBFP when selected criteria is current only.
In case when the current based protection activates so that either Iset and/or I0Sset current threshold
setting is exceeded the counters for retrip and CBFP start to calculate the set operating time. The
tripping of the primary protection stage is not monitored in this con guration and if the current is not
decreased under the setting limit rst is issued retrip and if the current is not decreased in time also
CBFP will be issued to upstream breaker. If the primary protection function clears the fault e.g. the
circuit breaker operates normally the counters for retrip and CBFP are reset immediately the current is
measured below the threshold settings.
AQ-T257
Instruction manual
Version: 2.00
© Arcteq Relays Ltd
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