The device is based on well known INA3221 3-channel current and voltage sensor. The channels are independent and can measure different power sources (common ground).
The device should be simple to assemble and not require custom PCBs (though I'm a big fan of custom designs).
Maine functionality:
- Measure the current/voltage/power of each channel (short-term)
- Measure the efficiency of DC-DC converters (short-term)
- Support logging to SD card (mid-term)
The initial prototypes of the UI were done using HTML & CSS.
The top bar will, in some way, show the current mode (standard or measuring DC-DC efficiency) and battery voltage. Then we'll have three rows, one for each channel. When the "efficiency" mode is selected, the last channel will disappear, and the resulting percentage will be shown instead.
First of all, the idea to build a power meter that can measure the efficiency of DC-DC converters is quite old though was constantly postponed. But now, when Russia strikes civilian infrastructure in my country (including power plants), and we use different battery-powered devices, voltage converters, and power banks a lot - it'll be really useful.
In the photo, you can see the main components that are required for the project: