What is the role of a relay in a control circuit?

The role of a relay in a control circuit is to operate as an electrically controlled switch. Relays are electromechanical devices that utilize an electromagnetic coil to mechanically operate a switch. When an electrical current flows through the coil, it creates a magnetic field that moves an armature, closing or opening the switch contacts. This allows the relay to control a larger circuit with a smaller current, enabling it to turn on or off devices such as motors, lights, or other types of electrical equipment without the need for a direct manual intervention.

This capability is essential in automation and control applications, where relays can isolate different sections of a circuit, provide overload protection, and facilitate complex control logic through interlocking or sequencing functions, making them a fundamental component in many control systems.