A relay is an electromagnetic switch that opens or closes a set of contacts when a control signal is applied. It operates on the principle of electromagnetism, using a coil and a movable armature to control electrical connections. The coil is energized, generating a magnetic field that pulls the armature toward it, causing the contacts to either open or close, depending on the relay's design. This action allows the relay to control high-power circuits with low-power signals, making it a critical element in automation and control systems.

    Types of Relay Functions

    Switching Functions: The most common relay function is switching. Relays can open or close electrical circuits in response to a control signal. This function is widely used in systems requiring the control of electrical loads, such as lights, motors, or heaters. For example, a thermostat in a heating system uses a relay to turn the heating element on and off based on the room temperature.