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

A relay is an electromechanical switch used to control a larger current circuit by using a smaller voltage or current to operate it. This function is essential in various electrical applications where a low power control signal is needed to operate higher power devices, allowing for safe and efficient operation of the circuit. The operation of a relay typically involves utilizing an electromagnet to open or close a set of contacts. When the small control signal energizes the relay coil, it creates a magnetic field that moves a switch, thus turning on or off the larger circuit without the need for direct electrical connection between the control and the output circuits.

This ability to control larger currents with smaller signals is crucial in many systems, especially in automation and control applications, where low-power signals can manage heavy machinery or high-power devices. The focus on relays emphasizes their role in providing safety and protection in electrical systems while allowing for versatility in controlling various electrical loads.