In this article, we are going to control two 12v lights with a 5v signal using a 12v relay and a button. This is a very simple project to show the operation of a control relay. This relay module requires 5v to operate. It has a double changeover switch that can switch 10amps AC at 250 volts and also, the 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 and also used in early computers to perform logical operations.
The Arduino relay module is designed for a wide range of microcontrollers like the Arduino board, AVR, PIC, ARM, with digital outputs. In this module, we have incorporated two relays.
Working of Relays
When the voltage is removed from the coil terminal, the spring pulls the armature back in its ‘at rest’ position and breaks the circuit between the terminals. So, by applying or removing power to the coil (the low current circuit) we can switch the high current circuit on or off. This way, we control the relay.