What's inside a Minature Circuit Breaker (MCB)
05 December 2013
Ever wondered what the inside of an MCB looks like.
1. Actuator lever - used to manually trip and reset the circuit
breaker. Also indicates the status of the circuit breaker
(On/Off/tripped).
2. Actuator mechanism - forces the contacts together or apart.
3. Contacts - Allow current to flow when touching and break the
flow of current when moved apart.
4. Terminals
5. Bimetallic strip
6. Calibration screw - allows to adjust the trip current of the
device after assembly.
7. Solenoid
8. Arc divider / extinguisher
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