- Solar powered
- ORP & pH (Optional) Sensors
- Estimates Sanitizer ppm (Optional)
- Home Assistant Integration
- Firmware is using esphome
- Update May 2025: I removed pH probe (3rd broke in 2 years) in December and have been running on just ORP measurements (ORP probe has been much more reliable). Once ORP measurement goes outside the 'green' table range, perform manual pH & alkalinity measurement, balance, then balance ORP with sanitizer. I think pH probe is not worth the cost/hassle in replacement - convenience it adds is marginal, since you still need to measure alkalinity manually.
- Update Dec 2024: Replaced worn-out ORP probe and added SMA Panel adapter. Decreased sampling rate to 1/hour to help battery last when there is little sunshine.
- UM FeatherS2 ESP32 board from here
- 2500 mAh
- Atlas Scientific Gravity Analog ORP and pH Kits
- Enclosure: DS-AT-0811-S
- Waterproof SMA Panel Adapter SMA-ADP
- 2x100 kΩ resistors for battery monitoring (optional)
- Adafruit Universal USB / DC / Solar Lithium Ion/Polymer charger - bq24074
- 3.5mm / 1.1mm to 5.5mm / 2.1mm DC Jack Adapter
- Small 6V 1W Solar Panel
- JST-PH 2-pin Jumper Cable
- Diagram
- NOTE: You can skip the ambient sensor removal step
- Install Python (Tested 3.13.3)
- Open Command Prompt
pip install esphome==2024.12.4- copy
wifi_example.yamltowifi.yamland edit the new file - Connect the board via USB and enter
esphome run tubby.yamlon the command line. This will build and upload firmware to the board. - In Home Assistant, create a helper switch
input_boolean.ota. Enable this switch, it will prevent deviceDeepsleep. - Power cycle the board, Device then enters
Lightsleep for15 minutesbefore it shows up in Home Assistant - Once your esphome device is added to Home Assistant, Use Device's page, Diagnostics section to calibrate the probes:
ORP Cal: mV ORP calibration offset from raw ADC value. Note:ORPmV Sensor value has calibration appliedpH 10 Cal: mV reading frompH Rawsensor while submerged in pH 10 calibration solutionpH 7 Cal: mV reading frompH Rawsensor while submerged in pH 7 calibration solutionpH 4 Cal: mV reading frompH Rawsensor while submerged in pH 4 calibration solutionppm Factor: 1 - Chlorine, 3 - Bromine
- Turn off
input_boolean.otato allow the device to save some power. - Place the probes in the water, and enjoy!
- pH + ORP -> Chlorine ppm Conversion Table
- Machine Learning Notebook
- Generate .h file from .tflite:
xxd -i model_fc.tflite > model_fc.h