ESP32 DC power meter: INA219 and OLED
Open in the lab ▸Make my own copy
An INA219 sits in the + wire of a 12 V load and measures the tiny voltage across its 0.1 Ω shunt (current) and the voltage after it (bus). The ESP32 reads both over I²C, works out watts, adds up watt-hours and shows it on an OLED on the same two wires. Put it between a solar charge controller and a load to see what your lights really draw. Open it and press Run: the sketch is inside the board (click the board, then Code). Every part, pin and resistor matches what you would build on a real breadboard; the guided build of the same name has the test sheet and hidden faults.
What is on the bench
6 parts, 14 wires, with a sketch (the program runs in the lab). Boards: ESP32 DevKit.
| Bench power supply | 2 |
|---|---|
| ESP32 DevKit | 1 |
| INA219 current sensor | 1 |
| Resistor | 1 |
| OLED display (I²C) | 1 |
Put it on your page
The project runs live inside the frame: readers can press buttons, turn knobs and read the meters.
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Link
https://zencircuitlab.com/p/zclcpower
Published by its author under the lab's community terms: it may be opened, copied and changed by anyone. Simulation results are for learning; check a real build against the parts' datasheets.