At its core, the Optocoupler Protected Relay Module integrates two key elements： an optocoupler and a relay. The optocoupler (also known as an optoisolator) is an electronic component that transfers electrical signals through light, providing galvanic isolation between its input and output. This isolation protects the low-voltage control circuitry from high-voltage spikes or electrical noise. The relay is a switch that controls the flow of electricity to a load, such as a motor, light, or other high-power devices. The combination of these two elements allows the module to handle high current and voltage while protecting sensitive control circuits from damage.