Introduction: DIY Wireless Bluetooth Multimeter

About: I'm from India and love making projects on electronics, specially with arduino. Internet is the only guidance I have and I've been into these since I was 11.

Anyone who has ever tinkered with the electronics and things knows the importance of the Voltmeter, and sometimes it is even convenient to add the Voltage measuring capability inside of your project. But sometimes we have our project deeply embedded into something and we just cannot probe in our Multimeter or Voltmeter, to get around this it is nice to put something by which means we would know the voltage.

In this tutorial, I will show you how you can measure up to 25V with Arduino via Bluetooth module through your phone.

Following is the video tutorial for this--

Step 1: Things Required

1.) Bluetooth Module -- This will allow Arduino and your phone to communicate through Bluetooth.

2.) Arduino -- A well-known microcontroller platform, I am using Arduino Nano

3.) A Phone with Bluetooth Serial Monitor application installed/

4.) Jumper Wires -- For Connecting Bluetooth Module to Arduino

5.) Computer with Arduino IDE installed

6.) A voltage divider module for measuring voltage, I am using readymade voltage divider module, you can make one yourself if you want, but if you don't have the required resistors, you can on,y measure the voltage upto 5V, anything above and your analog pin of Arduino will be fried.

Step 2: Conection of Bluetooth Module to Arduino

First, connect the Bluetooth module to Arduino in following way --

Rx -- Tx

Tx -- Rx

\Vcc -- 3V

Gnd -- Gnd

Step 3: Connect Voltage Sensor Module or Voltage Divider

Now connect the voltage divider to Arduino in the following way --

5V -- 5V

Gnd -- Gnd

Sig -- A0

Now, Download the code from this link and upload it to your Arduino.

Step 4: Testing

Now, Pair the module to your phone, then go to the Serial Monitor app and connect it, it will show the voltage on the range depending upon your voltage divider, from 0V to 25V in this case.

To have a look at how it works, I recommend having a look at the video tutorial in the intro of this project.

Thanks for reading!