The quality AC contactor is mainly composed of electromagnetic system, contact system, arc extinguishing device and auxiliary components.

1. Electromagnetic system. The electromagnetic system of the quality AC contactor is mainly composed of three parts: coil, iron core (static iron core) and armature (moving iron core). Its function is to use the power-on or power-off of the electromagnetic coil to make the armature and the iron core attract or release, thereby driving the moving contact and the static contact to close or break, so as to realize the purpose of connecting or breaking the circuit.

2. Contact system. According to the contact situation, the contacts of the quality AC contactor can be divided into three types: point contact type, line contact type and surface contact type.

3. Arc extinguishing device. When the quality AC contactor disconnects a high current or high voltage circuit, a strong arc will be generated between the moving and static contacts. Arc is a discharge phenomenon produced by the gas between the contacts under the action of a strong electric field. On the one hand, the arc will burn the contacts and reduce the service life of the contacts; on the other hand, it will prolong the circuit breaking time, and even cause arc short circuits or fire accidents. The higher the voltage, the higher the current and the higher the temperature of the arc zone during the contact opening and closing process, the stronger the arc. In low-voltage electrical appliances, measures such as lengthening the arc, cooling the arc or dividing the arc into multiple sections are usually used to promote the arc to be extinguished as soon as possible.

4. Auxiliary parts. The auxiliary components of the quality AC contactor are the reaction spring (return the contact when the coil is de-energized), buffer spring (reduce the impact force when the coil is closed by the armature), and contact pressure spring (increase the pressure when the contact is closed, reduce the impact force) Small contact resistance), transmission mechanism and base, terminal, etc.