Before we understand the wiring of contactor self-locking, we should first understand the principle of contactor, and the normally open and normally closed contacts. We don't know anything about these wiring. Let's first explain the principle and structure of contactor.

380伏交流接触器有三个主触头也就是电源进线和负载端出线，进线分别是三相火线L1L2和L3,负载端出线分别是T1T2和T3,接触器主触头进线和出线上下一一对应，分别是L1对应T1,L2对应T2L3对应T3,主触头在接触器不吸合的状态下是常开状态.

380 V AC contactor has three main contacts, that is, power supply incoming line and load end outgoing line. The incoming line is three-phase live line L1L2 and L3 respectively, and the load end outgoing line is t1t2 and T3 respectively. The incoming line and outgoing line of main contact of contactor are one-to-one corresponding, L1 corresponding to T1, L2 corresponding to t2l3 corresponding to T3 respectively. The main contact is normally open when the contactor is not closed

什么是常开？常开的意思就是说触点是断开的，不联 通的，常闭的意思就是说触点是联

What is normally open? Normally open means that the contact is open, not connected, normally closed means that the contact is connected

通的，常开和常闭一定要充分理解才可以

General, normally open and normally closed must be fully understood

接触器还有一个常开辅助触头，也就是右方的第四个接触器触点，上下也是一一对应，接触器不吸合一直是常开状态，辅助触头的作用就是辅助按钮控制接触器的，而主触头的作用是控制负载端的，所以分为主触头和辅助触头。

The contactor also has a normally open auxiliary contact, that is, the fourth contact on the right, which is one-to-one corresponding to the top and bottom. The contactor is always normally open when it does not pull in. The function of the auxiliary contact is to control the contactor by the auxiliary button, while the function of the main contact is to control the load end, so it is divided into the main contact and the auxiliary contact.

那接触器怎样才能吸合运转呢？要想接触器吸合那只有让接触器线圈通电，接触器才会吸合，交流接触器线圈电压有220伏的也有380伏，线圈电压接线的两个触点分别是A1和A2，也就是说线圈A1和A2只要有电，形成220伏或者380伏电压接触器就会吸合，这样应该很好理解。

How can the contactor pull in and operate? In order to pull in the contactor, only when the contactor coil is energized can the contactor pull in. If the coil voltage of AC contactor is 220 V, it also has 380 v. the two contacts of coil voltage wiring are A1 and A2 respectively. That is to say, as long as the coil A1 and A2 are energized, the contactor will pull in when it forms 220 V or 380 V. This should be well understood.

线圈的位置在接触器的后方中间的位置，它的作用就是通电以后线圈产生电磁，而在接触器前方中间的位置有块衔铁，接触器线圈通电产生电磁以后开始吸住前方衔铁，而衔铁又推动接触器主触头和辅助触头的上下触点，所以接触器常开触点变为常闭触点，常闭触点会变为常开触点。

The position of the coil is in the middle of the back of the contactor. Its function is to generate electromagnetic field after the coil is electrified, and there is an armature in the middle of the front of the contactor. After the contactor coil is electrified, it begins to absorb the armature in front, and the armature pushes the upper and lower contacts of the main contact and auxiliary contact of the contactor, so the normally open contact of the contactor becomes normally closed contact, The normally closed contact will become normally open.