An ESP32-based device that measures the amount of water in the reservoir and triggers SMS warnings when above a certain threshold.

• ESP32 board
• 16x2 i2c LCD
• HX711 weighing module
• Small wire (touch sensor)
• Breadboard power supply module

Before getting the weight of objects, you first need to calibrate your load cell by obtaining the calibration factor. Run the file calibrate_scale.ino to calibrate the scale.

1. Prepare an object with a known weight (i.e. a glass of water with 300g).
2. Upload the calibration code to your ESP32.

• The HX711 weigh module (previously calibrated) weighs the AC water tank;
• The weight is mapped: 200g -> 0% and 2000g -> 100%;
• A task running in parallel sends the mapped weight to ThingSpeak every 16 seconds;
• If the mapped weight exceeds 70 (%), an SMS is sent warning of the water tank level;
• An LCD shows the measured weight; its backlight stays on for 5 seconds when a touch sensor is activated.