This circuit breaker adopts porcelain pole structure, spring operation device and it can undertake tasks like opening operation and closing operation nearby or remotely. It also has the advantages such as excellent interruption performance, short arcing time, long electrical endurance, simple structure and convenience to be installed and maintained. Moreover, it can be used to open or close load current, overload current and short-circuit current. It was applicable at transformer substations, power plants, rural power distribution automation grids and occasions where frequent operations are needed.