See Post Fuel Level Float Type Senders Question
Scott,
Once you understand what you need to do it is quite straight forward.
The system initially indicates the float level in some arbitrary digits; probably millivolts I suppose.
Whatever they are, you need to ADJUST the indications such that the FULL reading indicates 16 Gal more than the EMPTY reading. (The float will hit the top of the tank at around 16 gals.)
This Adjustment is called the AUX SF (Scale Factor).
You then need to subtract the empty reading from BOTH readings so that they read 0 and 16 gallons respectively. This is called the AUX OFF (Offset).
So what you need is the raw readings for tank at empty and at full.
You start the procedure by setting the AUX SF Scale Factor to 100 (effectively100%) and the AUX OFF to zero and recording the raw readings from the tank at EMPTY and at FULL.
You will get numbers displayed like 199 empty and 256 full respectively.
The difference here (256-199) is 57 units, between the empty reading and the full reading, but you want the indicated difference between empty and full to read around 16 gal.
So you need to factor the raw readings of 199 and 256 by 16/57.
Now the readings will be 199 x 16/57= 55 and 256 by 16/57 =71
So now you have readings that are correctly scaled as 71-55=16gals from full to empty and the AUX SF (Scale Factor) has thus been calculated as 16/57 =0.28. Which is then multiplied by 100= 28 (converts it to a %)
Now we have Empty and Full readings of 55 and 71 respectively, so if with subtract 55 from both we have readings of 0 and 16 respectively. So the AUX OFF (Offset) is effectively 55, BUT it needs to be fiddled a bit with the Scale Factor and some other clever stuff that I don?t understand, as it must be an Odd number. But in essence, there you have it.
Scale it and then apply an Offset.
The exact GRT procedure is copied on my previous post titled:
"Fuel Level Float Type Senders Question".
At
http://www.vansairforce.com/community/showthread.php?t=10065
Pete.