This project allows you to build a pressure probe for liquid like water.
Especially for grey-water / rain-water.
The project is based on ESP32. You can drive it with solar-support and Li-Ion battery.
The ESP will operate in deep-sleep mode.
On the other hand you can drive the project with attached power supply for cabled reservoir.
Depending on your ESP version you need additional electronic components to reduce the current on
battery mode. In this project I used an ESP32-C3 with Li-Ion battery and low power devices.
Anyway you have to invest some parts like transistor to support the pressure probe with power at messure time to lower the power consumption.
This can be with easy circuits.
I used a 5 Watt PV-Module with 6Volt output to charge the battery. Feel free to purge-requests your solution.
The level will be transmitted only via Wifi to a MQTT server
The settings are configurable only in MQTT in folder cmnd.
Features
Configurable via MQTT
Two modes: battery and power-supply
Display support for SSD1306 OLED
Use a pressure probe like QDY30A
Configure your settings in App/App.hpp
no webpage support. All setting configurable via MQTT
Subscribed Parameter
Object
Values
Description
BatteryMode
0 or 1
0 = no battery (default), 1 = battery (deep sleep)
MqttIntervalSeconds
1 - 4294967295
MQTT publish intervall
ZistLower
0 - 4294967295
Lowest analog calibration value (0 %)
ZistUpper
0 - 4294967295
Highest analog calibration value (100 %)
ZistMaxLiter
0 - 4294967295
Maximum volume of tank in litre
Published values via MQTT
Object
Description
Battery
Battery voltage
Liter
Liter
Percent
Percent
ZistLowerValue
The actual lowest value of pressure probe
ZistUpperValue
The actual highest value of pressure probe
Pinouts
Pin
Description
GPIO2
Battery ADC voltage divider
GPIO4
Probe ADC voltage divider
GPIO10
Output for transistor base to switch VSS ON for probe