A PCB electromagnetic relay operates on the principle of electromagnetic induction. At its core, the relay consists of an electromagnet, a movable armature, contacts, and a spring mechanism. When an electric current flows through the relay’s coil, it generates a magnetic field, pulling the armature toward the coil. This movement either connects (in the case of normally open contacts) or disconnects (for normally closed contacts) the circuit that the relay is controlling.

    The actuation of the relay is not dependent on the load that it is switching, which allows a low-power signal to control a much larger power circuit safely. The ability to isolate the control circuit from the power circuit enhances the safety and longevity of both circuits.