Circuit breakers is the ability to closing, carrying and breaking current under normal circuit conditions and can closing, carrying and breaking current under abnormal circuit conditions within the prescribed time switch means. Divided according to their use of circuit breakers and low voltage circuit breakers high voltage circuit breakers, high and low Delimitation vague, generally referred to as high-voltage electrical 3kV above.
Breaker can be used to distribute electricity, no frequent start asynchronous motor, the implementation of the protection of power lines and motors, etc., when they are severe overload or short circuit, and undervoltage fault can automatically cut off the circuit, its function is equivalent fuse switch and through a combination of relays, etc. due to heat. And after breaking the fault current is generally no need to change components. At present, it has been widely used.
Electricity generation, transport, use, and distribution is an extremely important part. Distribution system including transformers and a variety of high and low voltage electrical equipment, low-voltage circuit breaker is widely used as a surface using large appliances.
Breakers are generally composed of a contact system, arc system, operating mechanism, trip, housing and so on.
When a short circuit, the magnetic field high-current (typically 10-12 times) to produce a reaction force overcomes spring release mechanism is operated pulling operation, switch the instantaneous trip. When the overload current becomes large, the heat intensifies, bimetal deformed to a certain extent promote institutional action (the larger the current, the shorter the operation time).
Electronic type, the use of transformers each phase current collection size, compared with the set value, the microprocessor when the current abnormal signals, the electronic trip unit driven operating mechanism action.
