what is power frequency withstand and impulse withstand of a
circuit breaker?
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Answer Posted / raghavendran
power frequency withstand capability of a CB is its
capability to with any over voltage at system frequency for
a definite period of time say 1min.
Impulse frequency withstanding capability is to withstand
the impulsive voltage levels for a predefined period of
time.say 1.2(rise time)/50 microsec(fall time),100KV
say(impulse voltage level)
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