How can I make a water level indicator panel for an RV fresh water tank? Answered
I'm rehabbing an RV.
It has a 100 gallon fresh water tank made out of plastic (polyethylene).
The tank has four built in sensors on the side of it, 0%, 25%, 50%, 75%,
I assume these sensors are just a bolt sticking through the side into the water.
How can I make a simple indicator panel which will light up an LED for 25%, 50%, and 75%?
I doubt I'd just be able to use the electrical conductivity between the 0% sensor and the other three, as the electrical resistance would be too high to send any usable connection through the water, am I correct?
But maybe something based on capacitance? Anyone know how to build something like that? My skills are too rusty to think that through.
Maybe I could cannibalize the sensor out of one of those touch sensitive table lamps and use it as the basis for my indicator panel?
I'd prefer not to use an arduino or pi for this, I need something incredibly simple and robust. I realize those would do the job but I need the quick and dirty solution.
Thanks in advance for your help.
EDIT: Here is a webpage that talks in depth about the standard tank monitors and how to upgrade it with an Arduino. Unfortunately, this seems incredibly over engineered for this task and I don't have the liberty of spending the time to do this, as I am working with a tight deadline. But it does discuss the resistor network which was originally used with the sensors on the tank. Since the original display panel on mine was too damaged to save, I thought it wouldn't be too hard to rig up something simple to replace it.