Arduino Bluetooth Appliance Controller Circuit

This project shows how to control a home appliance with Arduino.

Bluetooth module HC05 sends command from mobile.

Relay switches the AC load like bulb or fan.

Arduino Bluetooth Appliance Controller Circuit is simple and safe when wired correctly.

Good for beginners who want home automation.

Arduino Coding:

#include <SoftwareSerial.h>
SoftwareSerial BT(10, 11);

int relay = 7;

void setup() {
pinMode(relay, OUTPUT);
digitalWrite(relay, LOW);
BT.begin(9600);
}

void loop() {
if (BT.available()) {
char c = BT.read();
if (c == '1') {
digitalWrite(relay, HIGH);
}
if (c == '0') {
digitalWrite(relay, LOW);
}
}
}

Code Explanation:

• SoftwareSerial makes pin 10 and 11 act like RX and TX.
• Relay pin is set as output.
• Bluetooth sends characters like 1 or 0.
• When Arduino gets 1 it turns ON relay.
• When Arduino gets 0 it turns OFF relay.
• Relay controls AC load.

Circuit Working:

Parts List:

HC05 sends signals to Arduino.

Arduino reads TX signal and decides ON or OFF.

Relay module gets 5 volt from Arduino.

Relay works like a switch.

Phase wire from AC goes into relay.

Relay breaks or connects phase wire.

Bulb turns ON when relay closes.

Bulb turns OFF when relay opens.

How To build:

To build a Arduino Bluetooth Appliance Controller Circuit follow the below steps for connection:

• Take all the parts as shown in circuit diagram.
• HC05 VCC pin connect to Arduino 5V.
• HC05 GND connect to to Arduino GND.
• HC05 TX pin connect to Arduino pin 10.
• HC05 RX pin connect to Arduino pin 11 through a level shifter or voltage divider.
• Relay module VCC pin goes to Arduino 5V.
• Relay GND pin go to Arduino GND.
• Relay IN pin go to Arduino pin 7.
• AC phase wire from mains goes to relay input terminal.
• Relay output terminal goes to bulb phase.
• Neutral from mains goes directly to bulb neutral.

Conclusion:

This Arduino Bluetooth Appliance Controller Circuit is easy for beginners.

Arduino and Bluetooth give wireless control.

Relay lets us automate any AC appliance.

Good base project for bigger smart home systems.

References:

Creating a bluetooth controller