Keeping an eye on the power usage in your home comes with loads of benefits for the planet and your wallet, and this Raspberry Pi project makes it possible. With this Pi-based monitoring system, created by maker Mark Bryan Milligan, you can get an idea of what to expect when your power bill rolls around and accurately troubleshoot individual breakers when the power goes out.
The system uses the Raspberry Pi 3 A+, a smaller version of the 3 B+ which omits Ethernet, fitted with custom HATs connected directly to Milligan's breaker boxes. It helps keep track of not only power usage around the house but also monitors data from a few solar panels.
The HATs were designed by Milligan in EasyEDA and fabricated by an online PCB fabrication company. Each HAT has 16 TRS (Tip, Ring Sleeve) sockets that connect to $4 current transformers to read current information for individual breakers in each box. The housing shell was designed by Milligan and 3D printed using a Monoprice Select Mini 3D printer.
The system is designed to collect data from the Pis into a server which outputs information in real-time to an Android app. The app includes details about power usage in general and detailed data sets through graphs and more with a custom user interface.
If you are interested in tackling this project for yourself, a word of caution before you proceed. Mains voltage is deadly. If you have never worked with mains power before, seek the advice of those who are rated to do so, and ensure that your work is checked by a professional and up to code before applying power. Milligan's project uses clamp sensors over the power lines, this is the safest approach, but proceed with caution.