Fuel Capacitance Probes not working

[Don923]

My avionic shop gave me bad news that they did not have time to work on my fuel indicator issue anymore. I have the Dynon sending units and I think Dynon Capacitance on my RV-7 I was told I need to look at the CiES type sending units/float type. Has anyone gone through this issue in the pass. I see some forum threads dealing with RV-14s

 

[kiwipete]

Don

A little more information would be helpful.
Did you build the tanks? Was the capacitance of the plates tested? What dynon senders are you using?
The plates need to be checked to make sure there is no grounding. Then the senders need to be checked, finally the system needs to be calibrated.

There is a lot of information already on this site if you use the search function. As well as on the Dynon forums.

Regards Peter

 

[Don923]

Not much more information, I purchased this aircraft in December I put the Dynon Capacitance connectors from Dynon on in January, My plane and logs are in Texas, I just got word from the radio shop yesterday they could not make what ever system I have work, and that I needed to change to the CiES system and they had to finish up my project and move to another job, did not have time before moving to the next project to chase this issue. I hope to get my aircraft back This week but very unhappy they did not get the fuel quanity issue worked out.

 

[kiwipete]

Don

When you say you fitted Dynon senders - were the capacitance plates already in the tanks? Were they tested to ensure that they weren’t grounded?
If that’s all ok it should be just a matter of wiring to the Dynon and then calibrating the system.
I’ve had mine for 16 years the main thing I find as they aren’t temperature compensated the fuel temperature does affect the accuracy.

Regards Peter

 

[Don923]

Yes they were already in the tank when I purchased the aircraft, and the wing root had the BNC female connector, I connected the Dynon male plug to and these were connected to my Dynon EMS. I do not if they were grounded or not I would bet on not being grounded knowing how all the other wiring has been wrong also.

 

[kiwipete]

Don

you need to check the resistance of the plates to make sure they aren’t grounded. If that’s ok then check the wiring to the dynon.
If the plates don’t test correctly then I’d just buy floats and fit them per van’s instructions. A pretty straightforward job.

To be honest I use the fuel flow meter which gives me a far more accurate indication of remaining fuel. (Normally within 1/2 gallon once calibrated) and the tank gauges more as a backup.

Regards Peter