A 12 Volt relay is an electrically operated switch that allows a low voltage circuit to control a higher voltage circuit. The primary function of a relay is to provide electrical isolation between a control circuit and the power circuit, ensuring that a small amount of current can control a larger, potentially dangerous current.

    At its core, a relay consists of an electromagnet (the coil) and a set of electrical contacts. When a 12V DC voltage is applied to the coil, it creates a magnetic field, which then pulls or pushes a set of contacts, switching the high-voltage circuit on or off. When the voltage is removed from the coil, the contacts return to their default positions.