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Substation Equipment: Vacuum Circuit Breakers
Vacuum Circuit Breakers
A circuit breaker is a device used to complete, maintain, and interrupt currents flowing in a circuit under normal or faulted conditions. A vacuum circuit breaker utilizes a vacuum to extinguish arcing when the circuit breaker is opened and to act as a dielectric to insulate the contacts after the arc is interrupted. One type of circuit breaker is called a recloser. A vacuum recloser is designed to interrupt and reclose an AC current circuit automatically, and can be designed to cycle a set number of times before it must be reset manually.
Figure 1. Vacuum circuit breaker, inside
Figure 1. Vacuum circuit breaker, inside 		Figure 2. Vacuum circuit breaker, outside
Figure 2. Vacuum circuit breaker, outside

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