Circuit breaker refers to a switching device that can close, carry and break current under normal circuit conditions and can close, carry and break current under abnormal circuit conditions within a specified time. 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 voltage is relatively fuzzy. Generally, those above 3kV are called high-voltage electrical appliances.
Circuit breakers can be used to distribute electrical energy, start asynchronous motors infrequently, and protect power lines and motors. They can automatically cut off the circuit when they experience serious overload, short circuit, and undervoltage faults. Its function is equivalent to a fuse switch Combination with overheating and underheating relays. Moreover, it is generally not necessary to change parts after breaking the fault current. At present, it has been widely used.
In the generation, transmission, and use of electricity, power distribution is an extremely important link. The power distribution system includes transformers and various high- and low-voltage electrical equipment, and low-voltage circuit breakers are widely used electrical appliances.