circuit breaker

A circuit breaker is a device now often used in place of a fuse to protect electrical equipment from damage when the current exceeds a desired value, as in short-circuiting. The circuit breaker opens the circuit automatically, usually by means of a coil that separates contacts when the current reaches a certain value. One advantage of the circuit breaker is that the contacts may be reset (by hand or automatically) whereas a fuse has to be replaced. Small circuit breakers are used in the home, larger ones in industry.