Introduction
The electromechanical relay is an electrically operated switch that closes/opens a circuit by physically moving electrical contacts. The contacts move due to a magnetic field produced by an electromagnetic coil when a control signal is applied to it.
It is called as electromechanical because it has mechanical moving parts at the output circuit which are controlled by applying an electrical signal.
Construction
The electromechanical relay consists of various movable parts such as armature, contact, and spring. It also has stationary parts like contact, electromagnet (coil), and the wire wrapped as a coil.
Types of electromechanical relays
- Single pole single throw.
- Single pole double throw.
- Double pole single throw.
- Double pole double throw.