A miniature relay is an electrically operated switch that allows low-power circuits to control high-power circuits. The key function of a relay is to control a circuit by opening or closing contacts based on an electrical signal. This makes relays an important component in a wide range of electrical and electronic systems. Miniature relays are designed to perform the same tasks as their larger counterparts but with a reduced size, offering more compact designs for various devices.

    These relays work on the basic principle of electromagnetism. When an electric current flows through a coil inside the relay, it creates a magnetic field. This field then attracts a movable armature, which opens or closes the contacts. Depending on the design of the relay, it can either be normally open (NO) or normally closed (NC), determining how the contacts behave when the relay is not activated.