A Motor circuit breaker is a device integrating Low voltage circuit breakers and Thermal overload relays functions.
The motor circuit requires various roles,including disconnection, circuit on/off switching,short-circuit protection, device protection,motor control, and overload protection.
A motor circuit consisting of a Low voltage circuit breakers, Contactor, and Thermal Overload Relays is typically adopted and each of the devices has its own independent role. On the other hand, in a motor circuit consisting of a Motor circuit breaker and an Contactor, only motor control is provided by the Contactor ond other functions are provided by the Motor circuit breaker.
