In this blog, we will explore how a relay works, how to interface a single-channel relay with an Arduino Uno, and demonstrate a simple example of how to use the 5v relay module to control a lamp.

Connections are given Below : Arduino Relay Module +5V VCC GND GND PIN2 Signal Step 3 (Upload Sketch to Arduino) Download "sms_call_gate.ino" Sketch from the repository and Upload it to Arduino.