Why asymmetrical breaking current is higher than the symmetrical breaking current in a circuit breaker?

Why asymmetrical breaking current is higher than the symmetrical breaking current in a circuit breaker?
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1 Answer

Answer :

Asymmetrical breaking current is the rms value of the combined sum of the dc and ac components of the short circuit current at the instant of separation of the breaker contacts while symmetrical breaking current is the rms value of the ac component alone. Thus asymmetrical breaking current is higher than the symmetrical breaking current.
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