Answer Posted / suresh chand

The main purpose of anpumping relay is to protect Circuit breaker in fault condition when CB is receiving direct closing command.
if a circuit breaker is reciving direct closing command or there is any shorting in its closing circuit and simultaniously there is in fault then the CB then the will close and trip many times and will damage its pole. by proving antipumping contactor/relay the VCB will not close electrical again untill closing pulse is removed. It contact also comes in series with closing circuit hence also act as a interlock in closing circuit.

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