Circuit breakers are divided into high-voltage circuit breakers and low-voltage circuit breakers according to their scope of use. The division of high and low voltages is rather vague. Generally, those above 3kV are called high-voltage electrical appliances. Low-voltage circuit breaker is also known as automatic switch. Commonly known as "air switch" also refers to low-voltage circuit breaker. It is an electrical appliance that not only functions as a manual switch, but also automatically protects against loss of voltage, undervoltage, overload, and short circuit. It can be used to distribute electric energy, start asynchronous motors infrequently, protect power lines and motors, etc., and automatically cut off the circuit when they have serious overload, short circuit, and undervoltage faults. Its function is equivalent to a fuse switch and A combination of overheating and underheating relays. Moreover, it is generally not necessary to change parts after breaking the fault current, which has been widely used.
Air switch, also known as air circuit breaker, is a type of circuit breaker. It is a switch that will automatically open as long as the current in the circuit exceeds the rated current. Air switch is a very important electrical appliance in low-voltage power distribution network and electric drive system. It integrates control and multiple protection functions. In addition to completing contact and breaking circuits, it can also protect short circuits, severe overloads and undervoltages that occur in circuits or electrical equipment, and can also be used to start motors infrequently.