What is the main function of a relay?

The main function of a relay is to control a circuit by a low-power signal or to manage several circuits with one signal. This is accomplished through an electromechanical device that uses an electromagnetic coil to operate a switch. When a small current flows through the coil, it generates a magnetic field that closes or opens the switch, allowing or interrupting the flow of a larger current in the controlled circuit.

Relays are widely used in various applications, including automation, control systems, and protective devices. They enable control of high-voltage or high-current devices with minimal power input, improving safety and efficiency. Additionally, relays can facilitate the management of multiple circuits simultaneously, offering versatility in electrical systems.

This function is crucial in many designs, as it enhances the capability of simple control systems and ensures that handling high power does not endanger low power components or users.