Air switch within the more sophisticated, the principle is very simple, it into the cable outlet series between a 10 and 20 laps of the inductor, current enough suction driven mechanical lever action protection. Safer without changing insurance is a very good recommend. Automatic air-switch, also known as low-voltage circuit breaker, by operational agencies, contacts, protection device (breaker), arc systems, and other components. Can be used for making and breaking load circuit can also be used to control are not frequently starting motors. It function is equivalent to the knife switch, over-current, under-voltage relay, thermal relay and the leakage current protective device, electrical part or all of the functions sum, is an important protection in low-voltage distribution network. Automatic air circuit breaker protection (overload, short circuit, under voltage protection, and so on), adjustable operating value and breaking capacity high, easy to operate, safe and so on, so is widely used at present.