Forums » General Electronics Discussion

Hello, if you wouldn't mind, I have been working on this circuit for a week and it still is not working!!

I am trying to detect water by running 12V through a wire, if there's water, the "switch" will be closed, if no water, the "switch" will be open. I am then using that 12V to attempt to trigger a 5V (or 12V, either doesn't work) relay to then activate a water pump (takes 24V) whenever there isn't water.

https://www.circuitlab.com/circuit/5jxz68/waterdetector/

The issue is that I don't think I'm getting enough current through the relay because even though I can measure over 5V at both ends of the relay coil with respect to ground, the relay does not activate! If I remove the resistor R1, the voltage drops to less than 1V... HELP! Thanks

I think your problem is that when using the DC solver if you probe a AC line it will give you zero, also I don't know how the custom parts work. Here is my rendition you can change the state of switch SW and run DC solver to get voltages at different points.

Things to note, the resistance of the coil and the resistance your switch will have. Most importantly if this water is in pipes regular pipes it will be electrically grounded so all the current into the switch will go straight to earth. also don't kill yourself with water and electricity (bla bla you know this). Sounds like a cool project what are you doing?

I also don't want this circuit saved forever with my stuff so dose any one know if I delete it from my stuff will this link be broken?

" ... if I delete it from my stuff will this link be broken?"

Yes, it will break the link.

:(