Introduction: How to Turn ON AC Light and Fan by Clap Using Arduino and Sound Sensor

How to make a clap switch?? It's really easy to make AC appliances work just by snap or clap, be careful when you are using AC appliances , if you are novice please don't try this without understanding some basic stuff about electronics.

Step 1: Components Need and How to Connect the Components.

Arduino Uno

Sound sensor (digital output)

Relay Module

This video I made for double clap switch but both the hardware connections are same.

Note: Make sure you are connecting the sound sensor and relay according the Program.

Step 2: Arduino Program

int Torelay = 8; // signal to drive relay

int soundsensor = 7; // input from sound sensor

boolean state = false;

void setup()


pinMode(Torelay, OUTPUT);

pinMode(soundsensor, INPUT);


void loop(){

if (digitalRead(soundsensor) == LOW)



state = !state;

digitalWrite(Torelay, state);




copy the program and transfer the program to your arduino.

Step 3: Working of Clap Switch.

If you are looking for a dual clap switch take a look in this blog :


KonradK8 made it! (author)2016-12-15

Only one "click" sound need to on or off relay :)

asnah (author)2015-03-15

what type of relay?

About This Instructable




Bio: I make hobbyist stuffs and play with electronics follow me to know more
More by Magesh Jayakumar:Quick Start to Nodemcu (ESP8266) on Arduino IDECourse on MIT App Inventor and ArduinoHat for the Party
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