Capacitive Fuel Level Probe

Paul Thomas · #1 08-29-2009, 02:33 PM

I'm building the tanks and I'd like to understand my options, float vs. capacitive.

I though it worked by adding two plates at each end of the tank separated by a non-conductor (ie: nylon washer).

I checked GRT website to see what the preferred method for their avionics (didn't get my answer) and saw this probe.

Do you just mount this on the outside on the tank, through a hole? What's the difference between the 2 and 5 set points? $50 for another screws doesn't seem right so I doubt it's the way it's attached to the tank.

Thanks,

Ken · #2 08-29-2009, 05:34 PM

I have Van's plates in my tank with GRT. GRT supplies a part for that configuration and the part number is (surprise!) Vans Plate 2S. One required for each tank and I think they are about $ 75 each.

Ken

RV8RIVETER · #3 08-30-2009, 03:23 PM

Your picture appears to be a Princeton capacitive probe. May be wrong..

Probes are what "big" airplanes use and putting it simply is a verticle capacitor. The plates are two tubes one inside the other or a vertical plate inside an outer tube that vary in capacitance as the fuel level rises and falls. Usually installed on the upper surface and hangs down into the tank, but you need to check with manufacturer to be sure.

Paul Thomas · #4 08-30-2009, 04:36 PM

Quote:

Originally Posted by RV8RIVETER

Your picture appears to be a Princeton capacitive probe. May be wrong...

I believe you are correct. The picture is from GRT website, but spruce sells them as Princeton probes.

I'll try to call GRT tomorrow and find out how they're mounted and used. I'll also find out if I can use floats and their reported accuracy; it's much cheaper and I can use the $$$.