What does a relay do in an electrical system?

A relay is an electromechanical device that serves as a switch controlled by an electromagnetic coil. When an electrical current passes through the coil, it generates a magnetic field that closes or opens the contacts of the relay, thereby controlling the flow of electricity in a different circuit. This functionality allows the relay to manage high-current devices while being activated by a low-power signal, effectively providing isolation and control over large loads such as motors and lights.

In this context, the relay's ability to handle high current devices becomes crucial, especially when it comes to protecting sensitive components in an electrical system by allowing them to operate without direct contact with higher voltages or currents. This also contributes to safety and reliability in various applications where remote control or automatisation is required.