What is a relay in the context of electrical systems?

In the context of electrical systems, a relay functions as an electrically operated switch designed to open or close a circuit in response to an electrical signal. When a small current flows through the coil of the relay, it creates a magnetic field that either attracts or repels a movable armature, which in turn opens or closes the circuit connected to the relay. This mechanism allows for the control of high-power devices with low-power signals, enabling automation and remote control.

Relays are crucial in various applications, including safety systems, where they can activate alarms or shut down equipment in response to faults. Their ability to isolate different parts of a system while controlling the flow of electricity makes them invaluable in complex electrical setups. Understanding this function illuminates the fundamental role relays play in safeguarding and managing electrical systems effectively.