I've been working on an automated tank replenishment problem for a number of months now. Many of you have helped... thanks! But it is still a problem unsolved.
I'm trying to create something that can detect water pressure so that I can automatically drain a bit of tank on a regular basis, and have the water pressure detection device shut off the re-filling process when it detects a "tank full" condition. I have the bottom of my tank bulkheaded, so I can mount pressure sensing hardware under my tank without having to put junk in the tank - that is a goal. But until yesterday, all the water pressure sensing hardware I found either did not work, or was insanely expensive. You can read all about it in this thread
But yesterday I found the perfect device for sensing water pressure. I found it here
. There are two models, a gage and a differential model. The gage model (sensing water pressure relative to ambient air pressure) would be perfect. But there is a hitch... it requires circuitry to do anything with it.
Can any of you (maybe EE's out there) help me?
I've been going to Radio Shack on a regular basis since I was 9. And I'm OK with a soldering iron. But I cannot design a circuit.
The pressure transducer in question will output varying voltage based on the pressure it detects. That varying voltage needs to, at some determined point, throw a switch to either open (or possibly close) a circuit that controls the re-filling of a tank. That predetermined point needs to be "user adjustable", like with a potentiometer or something. That way you can change the point (or water depth) at which the re-filling process shuts off.
Can anyone out there design such a circuit? Is this trivial or difficult? Expensive or cheap? Easily done by a rookie or requiring professional assembly?
Any and all advice appreciated. Thanks in advance!