Circuit breakers

Circuit Breaker
Circuit breakers provide a manual means of energizing and de-energizing a circuit.
Unlike fuses, which must be replaced when they open, a circuit breaker can be reset once the
overcurrent condition has been corrected. Pushing the handle to the “OFF” position then back to
the “ON” position restores the circuit. If a circuit reopens upon reset to the “ON” position, the
circuit should be checked by a qualified electrician.
The fundamental of Circuit breaker operation
In the following illustration, an AC motor is connected through a circuit breaker to a voltage
source. When the circuit breaker is closed, a complete path for current exists between the voltage
source and the motor allowing the motor to run. Opening the circuit breaker breaks the path of
current flow and the motor stops. The circuit breaker automatically opens when it senses a fault
Circuit breaker

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