Company News

The contactor is how to be choose and use?

Date:2023-02-01

Contactor is an electrical appliance used to connect and disconnect circuits. Its function is to convert electrical energy into mechanical energy, and control the operation of electrical equipment through the suction and closing switches of the contactor. Contactors are divided into AC and DC. AC contactor generally adopts electromagnetic coil or electromagnetic contactor coil, and realizes various control functions by changing the closing and opening of contacts. DC contactor mainly consists of DC relay, DC excitation coil, AC excitation coil and various control circuits.

I

Basic principle

II

Structural features

III

classification

IV

working principle

V

control loop

Contactor is an electrical appliance used to connect and disconnect circuits.


Its function is to convert electrical energy into mechanical energy, and control the operation of electrical equipment through the suction and closing switches of the contactor.


Contactors are divided into AC and DC.


AC contactor generally adopts electromagnetic coil or electromagnetic contactor coil, and realizes various control functions by changing the closing and opening of contacts.


DC contactor mainly consists of DC relay, DC excitation coil, AC excitation coil and various control circuits.


1、 Basic principle


1. Basic structure schematic diagram of contactor


2. Electromagnetic system


3. Mechanical system


4. Composition and working principle of auxiliary contact


2、 Structural features


1. Coil: used to induce voltage and current.


2. Main contact board: used to select, adjust and connect circuits.


3. Auxiliary contact: installed on the contact plate, used to connect, disconnect or replace auxiliary wiring.


4. The layout of auxiliary contact and main contact is shown in the right figure:


3、 Classification


AC contactors are divided into main contact and auxiliary contact according to their purposes. The former is mainly used to connect the circuit and adjust the temperature, while the latter is mainly used to break the circuit and start the equipment.


It can be divided into master-slave type and master-slave type according to control mode:


It can be divided into moving contact system and moving contact and static contact system according to operation mode;


4、 Working principle


2. Main technical parameters of AC contactor:


3. Rated voltage of AC contactor: AC380V


4. Load capacity: 1.5 times of rated voltage.


5、 Control loop


(1) Control circuit of main contact


(4) Auxiliary electromagnetic device and its regulating system


Among them, the breaking capacity and breaking capacity of the AC contactor commonly used between the main circuit and the auxiliary circuit or the auxiliary circuit are determined by the conditions of the AC contactor itself, that is, the AC contactor can withstand a larger current on the premise of ensuring the breaking circuit and maintaining the breaking requirements.