Circuit breaker (English title: circuit-breaker,circuit breaker) refers to the close, carrying and breaking currents under normal circuit conditions and close together, within the time stated in the bearing breaking abnormal circuit conditions and current switching devices.
Circuit breakers can be used to distribute power, not frequently start asynchronous motors, power supply circuits and motors protection, when they are experiencing serious overload or short circuit and undervoltage fault can automatically cut off the circuit, its function is equivalent to fuse-switches and over/under combination of the thermal relay. After breaking fault currents and generally do not need to change the parts. At present, has access to a wide range of applications. Circuit breaker according to its use are divided into high-voltage circuit breakers and low-voltage circuit breakers, high and low pressure lines are vague, generally referred to 3kV high voltage apparatus.
In modern societies, whether in industry, agriculture, transportation, defense, culture, education, health, finance, Commerce, tourism, services and people's lives without electricity. Electricity generation, transmission, use, distribution is an extremely important aspect. Distribution systems including transformers and high voltage electrical equipment, low voltage circuit breakers is a wide use of electrical appliances.