Introduction: Bluetooth AC Voltage Controller

Now,here is my second Instructable,coming to the topic,now,this is an AC voltage controller made using Arduino and Bluetooth module attached to some relays and transistors controlled by an android mobile using an app....

Step 1: Gathering the Materials...

Here pre the list of parts that you need:
1- HC-05 Bluetooth module
2- Male and female jumper wires
3- Copper clad board
4- BC547 transistors x 3
5- 5408 diodes
6- 1000 microfarad capacitor(25v)
7- 12v(1 amp)[12-0-12] step down transformer
8- 5v relay x 3
9- Arduino uno
10 - All pins(you can also use male headers)

Step 2: The Power Supply

The power supply that we are going to make consists of a 12v step down transformer that transforms the socket current(220v in India) to 12v,but it is still AC current,to transform it into DC we are going to need a diode bridge,whose image is given,you can make a PCB for this but for the sake of convenience I just twisted them together....

Attach the 1000 mfd capacitor to the diodes as shown in the picture...

Step 3: The Relay Module

The relay module consists of 3 relays(which can be extended up to 6 as Arduino Uno has 6 pmw pins) which are connected to a transistor whose base pin goes to Arduino.The circuit diagram and traces are given in the images.(NOTE - The traces on the diagram are different from the traces on PCB at some points because of lack of space.).The pins marked as Co on the PCB are to be connected to analog pins on Arduino

Step 4: The Bluetooth Module

The Bluetooth module that we are going to use is HC-05,the pins to be connected on arduino are given below.(NOTE - These are from Arduino to Bluetooth module.)
5v - VCC

Step 5: The ARDUINO Code

So,here is the arduino code -

void setup() {
void loop(){
int value =;
case 65 : //65 is A
case 97 : // 97 is a
case 66 : // 66 is B
case 98 : // 98 is b
case 67 : // 67 is C
case 99 : // 99 is c
} }

Step 6: Putting All Together

As you have already connected the Bluetooth module,now connect the relay module as shown in the picture...

Connect the positive terminal to the power supply(diode bridge)[shown in the picture],to the Arduino Vin pin and negative to GND...

Putting it in a box will look nice...

The Co pins marked are to be connected to analog pins on Arduino

Step 7: How to Use

Download the app ArduinoRC from play store and open the Terminal Mode.Now the capital letter means onn and small letter means off,ex - 'A' means relay 1 onn and 'a' means relay 1off,relay two can be switch with letter B and relay 3 with letter C.You can modify the program for six relays as Arduino uno has six pmw pins...

Step 8: A Step of Thought...

You might fail many times before achieving success,its human nature,Once Einstein said that,if you never make mistakes,you never try something new,I am a newcomer here in Instructables,but still I hope that you liked the instructable,if so pleeease vote for me,I would like to thank the whole Instructable team for creating this wonderful website....
and remember my friends don't be afraid to make mistakes its just a part of the process...

MORE projects soon.....


About This Instructable




Bio: I am a 15 year old guy who is passionate about Arduino and programming,I like science but I love programming,I am also interested ...
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