Capacitane to Voltage Converter

[ma1owens]

Is the sensitivity on the capacitance to voltage converts adjustable? I started to calibrate my header tank (Glasair Super II SFT) which has a 6 gallon capacity and the calibration routine wanted a set point at each 1/2 gallon, Empty it read 3.28v and with .5 gallons it still read 3.28,
0 - 3.28
.5 = 3.28
1 = 3.29
1.5 = 3.29
2 = 2.30
2.5 = 2.30
3 = 2.31 I stopped there.

It looks to me like it would work if there was an adjustment to cause a greater spread.

 

[mmarien]

My main tank capacitance fuel sender only moved 0.5 volts for 14 points. The calibration is showing six digits so the fact that yours is only moving a hundredth of a volt doesn't necessarily mean it's not accurate.

 

[jakej]

What you are seeing at the start Is most likely because the fuel did not touch the sender until you added 1 gal (4litres approx).

Same situation as my Glasair

 

[kurtfly]

I also have a Glasair with capacitance plates in the Header tank and got a very small voltage change with each add. It works fine and accurate. I would just complete the calibration and see how well it works.

 

[ma1owens]

Re: Capacitance to Voltage Converter

I fixed the sensitivity issue by building Voltage converters using an Arduino Pro mini and a DAC (digital to analog converter) and a little bit of coding. I now have a spare set of Dynon Capacitance to Voltage Converters.

 

[Raymo]

The small change each 2 gallon made in my RV7A resulted in a warning by the Dynon system that there was little or no change. At first, I thought something was wrong and screwed the calibration. Had to do it again and ignore the warning, which should be removed, IMO.

As others say, it works very well once calibrated even with very small changes in voltage.