Contactor is to use coils to control circuit switching, contactors after power up, often closed, and normally closed open control.
1, circuit breaker main protection is the right to do. Its protection is currently in common use are three-stage protection, overload protection, short circuit a short delay, short-long delay. Some under-voltage, over-voltage protection. Depending on the brand, model and decide. Its closing can be manual or electric. Installation fixed, such as drawers in three ways. According to the current and voltage levels can be divided into low-voltage molded case circuit breakers, low voltage air circuit breaker and vacuum breaker. According to the trip curve can be divided into different situations. And fuse or is there much of a difference.
2, contactor is mainly used in industrial control, generally most of the load to the motor will, of course, there are some heaters, dual power switches and other occasions. Contactors switching is achieved by controlling the voltage. According to the different structures can be divided into a vacuum arc contactors and the General contactor. Depending on the control voltage can be divided into direct current contactors and contactor. Its main accessories for the auxiliary contact. Itself does not have a short circuit protection and overload protection, must be used in conjunction with fuse, the thermal relay.