--> Europa-List message posted by: "Peter Rees" <peter.rees05@ntlworld.com>
Thats exactly the problem we had. Problem is that the gauge was calibrated
for Avgas - when we changed to Mogas, the gauge said that the tank was
always 3/4 full.
If we had it re-calibrated for Mogas, when out touring, we would have to put
Avgas in and hence, have no reliable fuel indication.
I think that if this type of gauge is fitted, the AC should be placarded to
warn the pilot that the reading on the gauge may be wildly in accurate.
The Europa float gauge is already corrected for non linearity due to the
tank shape (by the position of the reed switches) and seems to work a treat.
----- Original Message -----
From: "Nigel Graham" <nigel_graham@btclick.com>
Subject: Re: Europa-List: Funny fuel gauge
> --> Europa-List message posted by: "Nigel Graham"
> <nigel_graham@btclick.com>
>
> Whoaa there! the facts are getting lost in the "Chinese Whispers".
> Capacitance gauges can be very accurate but you need to know how they work
> to get the best out of them.
> The Avelec, along with all other capacitance probes work by correlating
> the
> capacitance at the probe to a given volume of fuel using a programmable
> "look-up table". This gives another advantage that the fuel indication can
> be "linearized" to compensate for odd shaped tanks (i.e. the Europa tank).
> Since different fuels (Mogas, Avgas etc) have different dielectric
> constants, a capacitance gauge calibrated for one type of fuel will not
> give
> the correct reading if a different fuel is used - and that is the %age
> "error" quoted by Avelec. Get water in the tank and the gauge will read
> zero.
>
> If you regularly use the same fuel (as most Rotax drivers tend to) and
> don't
> fill up with water too often, you will not have a problem.
> If you do want the flexibility to change fuels - go for a
> magnetic-float-and-reed-switch type gauge.
>
> Either is preferable to the sight tube "attitude indicator" (IMHO of
> course
> ;-)
>
> Nigel
>
> ----- Original Message -----
> From: <EuropaXSA276@aol.com>
> To: <europa-list@matronics.com>
> Subject: Re: Europa-List: Funny fuel gauge
>
>
> --> Europa-List message posted by: EuropaXSA276@aol.com
>
> In a message dated 5/18/2005 4:16:16 PM Central Standard Time,
> peter.rees05@ntlworld.com writes:
> We had the Avalec capacitance gauge - by their own figures, it could give
> errors of 10% plus from one type of avgas to another and 50% plus if you
> use
> Mogas.
>
>
> 50% error?!!! And how is this better than the factory sight tube? Has
> anyone
> else had this problem with the Princeton model? I had planned on ordering
> mine this month!
> < It's always something>
>
> Brian Skelly
> Texas
> Europa # A276 TriGear
> See My build photos at:
> http://www.europaowners.org/BrianS
>
>
>
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