Explain the working principle of the circuit breaker

Explain the working principle of the circuit breaker
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1 Answer

Answer :

A:Circuit Breaker is one which makes or breaks the circuit.It has two contacts namely fixed contact & moving contact. Under normal condition the moving contact comes in contact with fixed contact thereby forming the closed circuit for the flow of current. During abnormal & faulty conditions(when current exceeds the rated value) relay senses the fault and gives signal to circuit breaker. Hence the moving contact of circuit breaker separates from fixed contact and an arc is produced between them & thereby it forms the open circuit. Arc is extinguished by the Arc Quenching media like air, oil, vacuum, SF6 gas etc.
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