MHZM1 plastic case circuit breaker is suitable for circuits with AC 50Hz, rated voltage of 400V and below, and rated current of 10A to 1250A. It is generally used for power distribution protection, and rated current of 630A and below can also be used as motor protection. Under normal circumstances, the circuit breaker can be used for the infrequent switching of the line and the infrequent starting of the motor respectively.