In this article, we are going to control two 12v lights with a 5v signal using a 12v relay and button. This is a very simple project to show the operation of a control relay. This relay module needs 5 volts to operate. It has a double changeover switch that can switch 10amps AC at 250 volts as well as DC supply.
A relay is defined as an electrically operated switch. Its main use is to control circuits by a low-power signal. The first relay was used in long distance telegraph circuits as amplifiers. Relays were also used in early computers to perform logical operations.
The Arduino relay module is designed for a wide range of microcontrollers. Such as the Arduino board, AVR, PIC, ARM, with digital outputs. This module we are using is incorporated 2 relays.
Working of Relay
When voltage is removed from the coil terminal the spring pulls the armature back into it’s ‘at rest’ position and breaks the circuit between the terminals. So by applying or removing power to the coil (the low current circuit) we switch the high current circuit on or off. This way we can control relay.