Wifi addon for Claber(R) irrigation control

The box fit with an existing claber irrigation control system (this is the 8425 aquauno pratico) that drives a solenoid 9v valve. The original one has a simple start/stop button.

Here I used a ESP8266 with tasmota firmware, a DC-DC downconverter for obtaining an additional 5v from the 9v battery and a DRV8833 for driving the solenoid valve.

The solenoid valve is latched and it needs a +9v for opening and -9v for closing, so I used the DRV8833 that is a very small motor RC driver. Two of the four motor input are controlled by the ESP8266 using two GPIO pin set as interlocked. An additional GPIO pin is used to put out the DRV8833 from the sleep mode saving battery.

The button is programmed to force the valve opening for 5 minutes and to force to stop the opening if the valve is already opened.

The led indicates the valve opening status. 

The ESP8266 with the tasmota firmware can be programmed in thousand way (from web GUI, from internal rules set, MQTT and so on) can be connected via wifi and support sleep mode for energy saving.

This project want to be a basis for future integration in my home domotic infrastructure.

WEMOS D1 -ESP8266  - Firmware TAMSOTA 

LM2596 DC-DC Buck Converter Step-Down Power Module Output 1.25V-35V

DRV8833 

Led 3mm

Momentary Push Button switch

 UPDATE 29 May 2021

The actual hardware, using the D1 in deepsleep mode, is consuming an average of 7mA.

(Most of the power seems dried by the downconverter)

A normal 9V battery has a charge of about 800 mAh. That means that in this configuration the maximum duration is 110 hours. Definitely too short battery life time.

The target should be 1y or at least 6 months. In the 6 months scenario the target is about 18uA, that means 100 times less than now. :(((