What does a definite purpose contactor do?

What are definite purpose contactors?

Let’s start with the purpose of contractors:

Connectors are the device that is used to transfer the power circuits. Moreover, you can use that device to transfer electric supply from one segment to another like u can control the direction of the air conditioning vents or use that in the heaters.

This device uses for high voltage electric devices which are commonly consuming more than 15 amperes. Moreover, contractors are designed to control the suppress the arc generates during the interruption of heavy motors.

When the electricity is passed through the electromagnet field. The electromagnetic field is generated and in the result, the central coil starts the rotation and when we cut-off the electric supply, the central coil is coming back to its rest position and open its junctions.

There are two DP contractors which are divided into two branches. Which is depending on the application:

Compact 1- and 2-pole contactors (Loading capacity 20 – 40 amperes)

That contractor is commonly used in home appliances and it’s loading capacity in AC voltages are 24V,120V and 240V.

Standard frame DP contactors (Loading capacity 15 – 360 Amperes)

That contactor is used in industrial or commercial purposes like in industrial machinery, hotels, buildings, hospitals, and factories, etc. There are commercial Air Conditions up to 500 tons. By using that DP contactor we can also control the elevators, pumps, compressors, electric motors, cranes, heavy machinery, food processing plants and many more.

Basic Construction:

A contact is a part of contactor which performs as a current carrier which includes:

1. Power contacts

2. Contacts spring

3. Auxiliary contacts

There are three basic components of contactors:


Electromagnetic gives you the force to approaching the contacts.


The enclosure is the frame which is kind of insulated (non-conductor) material like Thermosetting plastic, Nylon 6 and Bakelite which work as a non-conductor for safety measure. Moreover, we can use that enclosure to protect the contactors from oil, dust as well as from the weather conditions to enhance their life span.

Coil input:

Coil input is the kind of core contractor which might be DC or AC as per the design of the contactor. The coil may be powered by the low or high voltage as the requirement of the motor, and the contractor is handling the device separately or may be controlled by the lower coil as per program in the circuit which may control the lower and higher voltage.

Ecocircuitbreaker.com listing of Schneider electric contactors, square d motor starter

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