Measuring current with ACS712

First of all i need to thank SOMEF for this opportunity and special thanks to my Supervisor Med Amine Chibani,Also all the members of the development & test team

Introduction

As a student engineer in Electro-Mechanics I had the opportunity for an internship at SOMEF which is the leader company in its field of business here in Tunisia, with products that varies from simple home switches to home automation and smart house implementation it presented for me a company that I need to visit and a chance to widen my professional experience.
So I applied and they accepted me in the department of development and testing, not going to go in all the details I just want to tell you about my project so here we go.

The Internship

Main task: Design and manufacture of an instantaneous current measurement module, able to visualize the values on the computer in real time

With my supervisor we detailed what the project was and its functionalities :

The module needs to be able to measure the current up to 5 A we chose the IC ACS712 for that,an LCD-1602 to display the values everything will be controlled by an ARDUINO-UNO, using its serial port we will relay the values and print them in real time on an excel-sheet.

My first challenge was to read the Data Sheet of the ACS712 to interpret the output signal according to the passing current, after finding the formula I had to write and test the program on the arduino and display it on LCD.
The Second Challenge was to find a reliable solution to visualize and save these values on Microsoft-Excel in order to draw the curve. For that I found PLX-DAQ which is a software add-in of the Parallax Data Acquisition Tool (PLX-DAQ) for Microsoft Excel Acquires up to 26 channels of data from a microcontroller and places them in the columns as soon as they arrive. PLX-DAQ provides easy analysis of spreadsheets of collected data.

After testing the features separately from reading ,  displaying on an LCD and the real-time acquisition of the values. All that remains was writing the program.

For the circuits he asked me to make a shield housing the LCD screen for the arduino and input for the measuring circuit. The second circuit had one power input and three USB outputs with the ACS712 in the middle of it to measure the passing current.
To make the circuits I used Autodesk EAGLE here’s some pictures:

And I used my CNC to make the PCB’s and I had an acceptable result.

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Now that circuits are made I needed a box for them so I made one using Autodesk fusion 360 for modelling and 3D printed them on my KOSSEL DELTA