Function of low-voltage circuit breaker

The function of the circuit breaker is to cut off and connect the load circuit and distribute the electric energy.

Circuit breakers are also called air switches. Its function is to cut off and connect the load circuit, cut off the fault circuit, prevent the accident from expanding and ensure safe operation. In the case of overload or abnormal operation of electrical appliances, if there is a fault, the circuit breaker will automatically turn off the switch to protect the electrical appliances and lines; In addition, the circuit breaker has a leakage protection device with leakage protection function.

Circuit breakers can be used to distribute electric energy, occasionally start asynchronous motors, and protect power supply lines and motors. When they have serious faults such as overload, short circuit, undervoltage, etc., the circuit breaker can automatically cut off the circuit, and its function is equivalent to the combination of fuse switch and overheating and underheating relay. Generally, it is not necessary to replace parts after breaking the fault current.

Characteristics of circuit breaker

1 and SF6 have good electrical properties and high breaking voltage. The operation, maintenance and overhaul of the equipment are very convenient, with long overhaul period, good breaking performance and small floor space. Especially, the development of SF6 enclosed combined electrical apparatus can greatly reduce the area of substation.

2. The oil-free circuit breaker uses less oil, and the oil tank is compact and firm, with the characteristics of material saving, explosion prevention and fire prevention. The oil-less circuit breaker is safe to use, greatly simplifies the distribution equipment, is small in size and convenient to transport, and is widely used at present.

3. The air switch has the advantages of large breaking capacity, fast action time, small volume, light weight and no fire danger, but its structure is complex and expensive, so it needs to be equipped with a compressed air system. Mainly used in 1 10KV and above systems with high requirements on electrical parameters and breaking time.