Electromechanical Relay

A relay is an electromechanical device having electrical, magnetic and mechanical components. The relays control the electric circuit by opening or closing the contacts of that circuit. An electromechanical relay consists of three terminals namely common (COM), normally closed (NC) and normally opened (NO) contacts. These can either get opened or closed when the relay is in operation. These relays can work on both AC and DC supply sources.

 

Working

 

In any type of electromechanical relay of the relay, the major components are coil, armature and contacts. A piece of wire is wound around a magnetic core so it forms an electromagnet.

When the supply is given to this coil, it becomes energized and produces an electromagnetic field. An armature is a movable part and its main function is to open or close the contacts. It is attached with a spring so that under normal working condition this armature comes back to its original position and the contacts are the conducting parts which connects the load and source circuits.