The universal circuit breaker is a powerful mechanical switching appliance. It has a strong current breaking capacity, rated current up to thousands of amperes, and excellent short-circuit breaking capacity. Various protection functions, covering long delay, short delay, instantaneous and ground fault protection, etc., can accurately detect and respond to a variety of circuit faults. Flexible operation mode, manual, electric and other options to adapt to different scenarios. It adopts modular structure, which is convenient for installation, commissioning and maintenance. Air-type circuit breakers are available in drawer type and fixed type, which are widely used in power system substations, distribution rooms and large industrial enterprises, high-rise buildings, rail transport and other places, and are important equipment for safeguarding electric power safety.