What is the function of a relay in an electrical circuit?

The function of a relay in an electrical circuit is primarily to control a circuit by a low-power signal. A relay is an electromechanical switch that uses an electromagnetic coil to actuate its contacts. When a low-power control signal is applied to the coil, it generates a magnetic field that moves the armature, allowing the contacts to either open or close, thereby controlling a larger circuit. This allows for the automation of various operations in a safe and efficient manner, where a low-power signal can control high-power loads without direct electrical contact.

In practical terms, relays are often used in applications such as automation, switching, and controlling various devices, making them essential components in industrial settings, particularly in systems where isolation of circuits is necessary. The ability to control a larger circuit with a smaller signal is crucial for minimizing risk and ensuring that sensitive components are protected from high voltages or currents.