What does a relay do in an electrical circuit?

A relay serves as an electromechanical switch in an electrical circuit. When a small electrical current is applied to the relay's coil, it creates a magnetic field that enables the relay to open or close contacts. This action can control a larger current flowing in a different part of the circuit, allowing for the automation of switching tasks without direct manual intervention.

Relays are crucial for controlling high-voltage or high-current circuits with a low-power signal and are often used in applications such as motor control, lighting, and automation systems. The ability to isolate separate circuits while controlling them enhances safety and reliability in electrical systems. Thus, characterizing a relay as a switch accurately captures its fundamental function in electrical operations.