Circuit breakers are automatically operating fuses
that interrupt the circuit in the event of an overload or short circuit and thus protect against damage. The basic function of circuit breakers is based on current measurement, which rises in the event of an overload or short circuit. The current rise causes a bimetal switch
to heat up, which breaks the circuit. Automatic circuit breaker
Unlike a fuse, which blows the fuse wire and must be replaced, an automatic circuit breaker, also known as a miniature circuit breaker, can be reset after tripping and is thus back to its basic function. Automatic circuit breakers are used in building services and are available for a wide range of rated currents. More powerful versions, the circuit breakers, are used in the power supply of municipalities and cities.