RDM5 series moulded case circuit breaker is applied to the circuit of AC 50HZ, insulation voltage 1000V, rated working voltage up to 690V, rated current up to 800A,which to distribute the power and protect the circuit and power source against overload , short-circuit and under voltage damage. Especially, when the current is lower 630A, it also can protect the motor. Normally breaker can infrequently invert and starting of motor. The product can be installed vertically and horizontally.