DEMA CPM 310 G User Manual page 112

tCBF (CB Pole Failure Delay Time)
tCBF is the delay time counter limit value before alarming, which is triggered at the instant that the
trip signal is generated, and terminated if the primary circuit current drops below the threshold
current. The setting zone for the counter is (0.01 – 10) s in 10 ms steps. The default value for tCBF is
1.0 s, however, tCBF value is not recommended to exceed 100 ms if the function is to be used in
blocking logic selectivity schemes.
WARNING!
CB pole failure supervision function is to be used as a preventive function to inform the users of a
possible CB failure. The absence of failure alarm from this supervision function is not to be considered
as guaranteed successful operation of the circuit breaker! General safety rules and live working
principles apply! □
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