The product is one of new circuit breakers developed by adopting international advanced design and manufacturing technology. This circuit breaker has characteristics of small size, high breaking capacity, short flashover and shock resistance. Its rated insulation voltage is 800V. In the circuit with AC 50Hz/60Hz, rated working voltage 690V and below (DC 250V and below) and rated working current up to 1250A, it is used for infrequent conversion and motor’s infrequent starting. The circuit breaker has protection devices of overload, short circuit and under voltage, which can protect the circuit and power devices from damage.