Electromagnetic relays are used in a variety of applications

An electromagnetic relay is an electrical switch that is activated by an electromagnet. It consists of a coil of wire, an armature, and a set of contacts. When the coil is energized, it creates a magnetic field that attracts the armature, causing it to move and close the contacts. When the coil is de-energized, the magnetic field disappears, and the armature is released, causing the contacts to open.

Electromagnetic relays are used in a variety of applications, including controlling the flow of electricity, switching electrical circuits, and providing isolation between two electrical circuits. They are often used in electrical control systems, automotive systems, and telecommunications systems.

Electromagnetic relays are classified according to the number of contacts they have (single-pole, double-pole, etc.), the type of contact (normally open, normally closed, etc.), and the voltage and current ratings of the contacts. They are also available in different sizes and enclosure types to suit different application requirements.