The contactor uses the coil to control the on and off of the circuit. After the contactor is energized, the contact of the normally open type contactor close and the contact of the normally closed type contactor open.
1. Circuit breaker is mainly used for protection. Now its more commonly used protection is three-phase protection, overload protection, short time delay for short-circuit, long time delay for short-circuit. There are some others protection functions such as undervoltage and overvoltage. It depends on the brand and model. Its divide-shut brake can be manual or electric. There are three types of installation methods: fixed type and drawer type. According to the size of the current and the operating voltage level can be divided into low-voltage moulded case circuit breakers, low-voltage frame circuit breakers and high-voltage vacuum circuit breakers. According to the different trip curves can be divided into different usage occasion
2, The contactor is mainly used for industrial control. The on-off of the contactor is achieved by controlling the coil voltage. According to the different structure of arc extinguishing, it can be divided into vacuum contactor and common contactor. According to different control voltages, it can be divided into DC contactor and AC contactor. Its main accessory is the auxiliary contact.