Irrigation control using battery powered valve


there’s no direct connection between those two modules.
Are the relays disconnected or connected to some load?
Is to the Channel A connected any sensor?
How do you power the Core Module?

Inductive loads can create false pulses. What happens if you disconnect the solenoid, or sensor (do you use that flow sensor?). That hall flow sensor can react to magnetic field from solenoids.

The solution (in case the issue is the switched noise) might be to use stronger pull-up. Instead of internal pullup you can use external pullup with lower resistance which is on the Sensor Module. Or add external one.


thank you very much… Your ideas helped me to find, what was probably causing that problem… My secound name can be The Battery Destroyer… (and probably I can be happy that core module still works)… Why? I soldered cables to battery module (behind the first “minus” and after the third battery “plus”) - to get 4,5V. It worked, on the cables were 4,5V. But… I used relay modules as it is metioned above (simulating H bridge) and I used the power from battery module for operating the valve. For switching the bistable valve I just needed some short pulse, so I switched to True on the first relay and False on the second one and after 100ms I switch one of the relays back to opossite state. So, there was + and + or - and - on both cables… On the cables which were connected directly to the battery module. I am not sure if I am describing it correctly, but I have damaged three brand new rechargable batteries :face_with_raised_eyebrow:

At this moment I am using isolated power supply for the valve (three AA batteries)… but it is not so nice solution (use 4 AAA batteries + 3 AA batteries). Can some diode help to use it on the + cable from the battery module?

The image how to DON’T do that…

@hub.martin you asked me once, how I am skilled in electronics… So at this moment you can imagine :electric_plug::fire: