Figure. 5.4.8 - 53. CBFP when "Current or DO" is the selected criterion.
When the current threshold setting of
I
set
and/or
I0
set
is exceeded, or the TRIP signal reaches the
primary protection stage, the function starts counting down towards the CBFP signal. The tripping of
the primary protection stage is constantly monitored in this configuration regardless of the current's
status. The pick-up of the CBFP is active unless the current is reduced below the setting limit and the
primary stage tripping signal is reset. If either of these conditions is met (i.e. the current is above the
limit or the signal is active) for the duration of the set CBFP time delay, a CBFP signal is sent to the
incomer breaker. The time delay counter for CBFP is reset as soon as the measured current is below
the threshold settings and the tripping signal is reset. This configuration allows the CBFP to be
controlled by current-based functions alone, with added security from current monitoring. Other
function trips can also be included to the CBFP functionality.
A
AQ
Q-M257
-M257
Instruction manual
Version: 2.07
© Arcteq Relays Ltd
IM00021
121
Summary of Contents for AQ-M257
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