Camp Sense
WattIsIt Hardware
A battery watt meter using ADS1115 and a shunt to measure power usage. The Arduino sketch is located in Arduino/WattIsIt. Been using the DOIT ESP32 DEVKIT V1 board.
Wiring Diagram
+ Positive battery terminal
- Negative battery terminal
L Low side of current shunt resistor
H High side of current shunt resistor
Bill of Materials (BOM)
AHT21 is optional, was used for humidity but also has a temperature sensor.
| Item | Link |
|---|---|
| U2 ESP32 | https://a.co/d/88cG9Z5 |
| M1 ADS1115 | https://a.co/d/gfCO6jt |
| U1 Voltage Reg | https://a.co/d/cpmFpuU |
| U4 AHT21 | https://a.co/d/6xBWBLx |
| U3 BMP280 | https://a.co/d/1HV9oyw |
| J1 Terminals | https://a.co/d/8nVocXb |
| J1 JST Connector | https://a.co/d/0xq4sMO |
| Shunt | https://a.co/d/7QWWK5O |
| R1 10k Ohm | https://a.co/d/6f4wvqz |
| R2 5.1k Ohm | https://a.co/d/adCeki6 |
Version 1.0
| KiCad Model | In Use |
|---|---|
 |
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Arduino Code
The Arduino sketch for the WattIsIt module is available in the Arduino/WattIsIt/ directory. This code handles:
- Reading voltage and current measurements from the ADS1115 ADC
- Calculating power and energy usage
- Bluetooth communication with the mobile app
- Optional temperature and humidity sensing