How AC contactors work

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Guide: AC contactor as a kind of contactor, widely used in automatic control systems, then what is the principle? Is the principle of the contactor the same? Next, let's take a look at it~~

First, the working principle of AC contactor - - Introduction

A contactor is an appliance that utilizes a current flowing through a coil to generate a magnetic field that causes the contacts to close to complete control of the load. As a kind of contactor, the AC contactor also performs the function of controlling the load, but only has a precondition on the original basis: the AC current flows through the coil. AC contactors have been widely used, and CJX2, CJ20, CJT1, B and other products are common.

Second, the working principle of the AC contactor - - structure

The AC contactor is mainly composed of four parts: an electromagnetic system, a contact system, an arc extinguishing device, an insulating casing and an accessory. The electromagnetic system further comprises an attracting coil, a moving iron core and a static iron core; the contact system 呦 comprises a main contact, a normally open auxiliary contact, a normally closed auxiliary contact; the arc extinguishing device is used for quickly cutting off the arc when needed, In order to avoid burning the main contacts; and the insulation shell and accessories often include various springs, transmission mechanisms, terminals and so on.

Third, the working principle of the AC contactor

When the coil is energized, the electromagnetic force generated by the static iron core will pull the moving iron core, thereby driving the three moving contact pieces, so that the main contact is in a closed state, the auxiliary normally closed electric shock is in an open state, and the auxiliary normally open contact is in a closed state. In the closed state, the power is turned on; when the coil is de-energized, the electromagnetic force generated by the static iron core disappears, the moving iron core is separated from the static iron core under the action of the spring, and the three moving contacts generate an action, so that the main contact is disconnected. The auxiliary normally closed electric shock is in a closed state, the auxiliary normally open contact is in a disconnected state, and the power is cut off.

Fourth, the working principle of the AC contactor - - use the connection method

Before using the AC contactor, you should understand its working principle and understand its external power supply characteristics to avoid problems caused by improper use. The connection method is roughly the same: general three-phase contactor has 8 points and 3 Input interface, 3 output interfaces and 2 control points. If you add self-locking, you need to connect an output interface to the control point.

How AC contactors work