A relay drive is a circuit or system used to control the operation of electrical relays. A relay is an electromechanical switch that opens or closes contacts based on the presence or absence of an electric signal applied to its coil. Relay drives are typically used to control devices such as motors, lights, heating elements, and other high-power electrical equipment. They are commonly employed in situations where low-power control signals (often from a microcontroller or digital circuit) are used to switch larger currents and voltages required by the load.

    In a relay drive system, the control signal energizes the relay coil, generating a magnetic field that attracts a movable armature. This movement changes the position of the contacts, either opening or closing the circuit that controls the load. The ability to control large electrical systems with relatively low power makes relays highly effective in automation and control applications.