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Yet another EIS question

H

Hwood

Well Known Member
In progamming the EIS, there is some higher "tax equation" math required in order to set the readout of the float levels from the fuel tanks. Does anyone have some good gouge for the Aux off and Aux sf values for a -8?

I figure this would be easier than draining the tanks to get the first value...

Thanks
 
And the -7?

While you are they chaps.
My mates -8 uses SF145/Off399 and SF151/Off453 for left and right tanks respectively.

Can anyone offer some figures for a -7.

GRT gave me SF100 and Offset 0. Which of course DON'T work.

I went to a lot of trouble fitting the Floats to ensure they gave the correct values (Ohms) as per the plans for empty and full and used a 470 Ohm resistor.
It is easy to fiddle the SF to get it to read what you want but with out the correct OFF it is meaningless.
How do you establish thew correct OFF.
Pete.
 
Has anyone tried measuring Aux voltage? It may not necessarily be convenient to do so, but if possible, it'd be the key to figure out these numbers. Measure one at empty and one at full (or take several measurements at known amounts of fuel) then work out the equation:

AuxDisplay = (AuxVoltage * AuxSF / 2.5) + AuxOffset


PS. I'm not yet at this stage, so I may be jumping the gun here :)
 
In looking back at this, I wanted to make one further point for those who haven't gotten to the point of pouring in fuel and calibrating the gauges. The reality is that with the dihedral of the wing, you are going to get no movement of the float arm for the first several gallons used, and then the movement is not exactly linear anyway. Since the EIS uses a linear equation to calibrate out gallons, you are only going to get a best guess anyway. What values you eventually decide to use depends on how you deal with the "ungaugable" fuel at the top end. That's kinda why I didn't fiddle with it too much - low return on time investment...

Paul
 
Fuel Calibration For Engine Monitor.

Paul,
What you say is true; if you ONLY have a GRT EIS.

However, if you have a Graphical Engine Monitor then in the set up pages for the Graphical Engine Display, the last item is Fuel Data Scale (Fuel Level Correction Entries) as discribed on page 46 of the EFIS manual.

If you have trouble locating it, let me know.
Pete.
 
You're right Peter, I don't think that was live in the EFIS software when I got mine (later version? I might well be wrong, and just missd it...) Of course, the EFIS still doesn't know what's happening at the top end of the tank, when the arm isn't moving - right?

Now you've given me something else I can't play with and try out until I get the airplane back from the paint shop! Still on schedule...it's just not schedueld out yet...

Paul
 
Paint shop

Hey, it's been a while since Doug posted some pictures from the paint shop...
 
rv8ch said:
Hey, it's been a while since Doug posted some pictures from the paint shop...
Click to expand...

That's right, it has been....heh,heh,heh.... :p ;)

Gotta build just a LITTLE suspense! :D
 
New thread

Well, since we're off on a tangent, might as well start a new discussion...

Let's guess what Paul's paint scheme is going to look like! I'll start...

Hmmmmm....maybe the shuttle?
 
Peter has too much time on his hands... :p

Lateral stabuility looks good - might be a bit of a problem in pitch though... :D

Paul
 
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