A power relay is an electrically operated switch that allows the control of high-power circuits by low-power electrical signals. In its most basic form, a relay consists of a coil, a set of contacts, and an armature. When an electric current flows through the coil, it generates a magnetic field that either attracts or repels the armature, opening or closing the contacts. This action enables the relay to control the power to an external device, such as a motor, light, or industrial machinery.

    Power relays are typically used in situations where the control circuit must be isolated from the power circuit, providing a safe and reliable way to manage high-voltage, high-current devices with a low-voltage, low-current signal.