When the coil is electrified, the static iron core generates electromagnetic force to pull in the moving iron core. Because the contact system is linked with the moving iron core, the moving iron core drives three moving contacts to act at the same time, the main contact is closed, the auxiliary normally closed contact mechanically connected with the main contact is opened, and the auxiliary normally open contact is closed, so as to turn on the power supply. When the coil is powered off, the suction disappears, and the linkage part of the moving iron core is separated by the reaction force of the spring, so that the main contact is disconnected, the auxiliary normally closed contact mechanically connected with the main contact is closed, and the auxiliary normally open contact is disconnected, so as to cut off the power supply.

一:一般三相接触器一共有8个点，三路输入，三路输出，还有是控制点两个。输出和输入是对应的，很容易能看出来。如果要加自锁的话，则还需要从输出点的一个端子将线接到控制点上面。

1： General three-phase contactor has a total of 8 points, three input, three output, there are two control points. The output corresponds to the input, which is easy to see. If you want to add self-locking, you also need to connect the line to the control point from a terminal of the output point.

二:应该知道交流接触器的原理。他是用外界电源来加在线圈上，产生电磁场。加电吸合，断电后接触点就断开。知道原理后，你应该弄清楚外加电源的接点，也就是线圈的两个接点，一般在接触器的下部，并且各在一边。其他的几路输入和输出一般在上部，一看就知道。还要注意外加电源的电压是多少（220V或380V），一般都标得有。并且注意接触点是常闭还是常开。如果有自锁控制，根据原理理一下线路就可以了。

2： First of all, we should know the principle of AC contactor. He uses an external power source to add to the coil to generate electromagnetic fields. The contact point will be disconnected after power on and power off. After knowing the principle, you should find out the contact of the external power supply, that is, the two contacts of the coil, which are generally at the lower part of the contactor and on each side. The other several input and output channels are generally on the top, which can be seen at a glance. Also pay attention to the external power supply voltage is how much (220 V or 380 V), generally marked with. And pay attention to whether the contact point is normally closed or normally open. If there is self-locking control, according to the principle of the line can be.

交流接触器的承载电流很大，一般是内部的吸合线圈来控制它的动作与否，而控制线圈又由与它串接的各种类型的继电器来操作，打雷之后会跳闸的是因为交流接触器的继电器带有过流或接地保护功能，当线路上落有雷电，它会控制交流接触器动作，切断负荷电源，来保护设备，以免被高电压，大电流损坏或是接地发生危险

The bearing current of AC contactor is very large. Generally, the internal pull-in coil controls its action, and the control coil is operated by various types of relays connected in series with it. After thunder, the relay of AC contactor will trip because it has over-current or grounding protection function. When there is lightning on the line, it will control the action of AC contactor and cut off the load power, To protect the equipment from being damaged by high voltage, high current or grounding

交流接触器广泛用作电力的开断和控制电路。交流接触器利用主接点来开闭电路，用辅助接点来执行控制指令。主接点一般只有常开接点，而辅助接点常有两对具有常开和常闭功能的接点，小型的接触器也经常作为中间继电器配合主电路使用。从而起到远程控制或弱电控制强电的功能.

AC contactor is widely used as power breaking and control circuit. AC contactor uses main contact to open and close circuit, and auxiliary contact to execute control command. The main contact usually has only normally open contact, while the auxiliary contact often has two pairs of normally open and normally closed contacts. Small contactors are often used as intermediate relays to cooperate with the main circuit. So as to play the function of remote control or weak current control strong current