A relay drive works by using a relay — an electromechanical switch — to control a high-power circuit using a low-power signal. The relay consists of an electromagnet, a set of contacts, and a spring mechanism. When a small control current is applied to the electromagnet, it generates a magnetic field that pulls the relay contacts together, closing the circuit and allowing current to flow through the load. Once the control current is removed, the spring mechanism causes the contacts to open, breaking the circuit and stopping the current flow.

    Relay drives are particularly valuable in applications where it is necessary to control high-voltage or high-current equipment from a low-voltage control circuit. By acting as an intermediary between the control system and the load, relays prevent the control circuit from being exposed to high-voltage spikes or currents, thus ensuring safety and longevity for sensitive components.