GRT Horizon 10.1 Fuel sending unit calibration

I'm setting up my GRT Horizon 10.1 in my RV8. I am using the stock Vans fuel tank sending unit with the Horizon. I've already filled it with gas so I am trying to get what settings other people used (AUXSF and AUXOFF)

Not sure you are going to get where you need to be without following the GRT procedure to calibrate FLOAT senders from Vans. If using capacitance probes I can’t help. Good luck.

http://grtavionics.com/media/Resistive-Float-Fuel-Senders-EIS.pdf

On my HXr unit, I used it and not the EIS to calibrate. Much easier. The manual tells you what config data to enter in the EIS to pass uncalibrated data to the HXr. The HXr has a nice tool for doing the calibration. Add a couple gallons, press a button, repeat.

I also thought that the HXr has input ports, with pullup's for the fuel senders so the EIS can be bypassed. Mine were already wired into the EIS, so didn't bother.

My settings

mine for my RV10 with GRT EIS are
AUX3 left fuel tank 52 -- 157
AUX4 right fuel tank 52 -- 151

As has been mentioned, follow the GRT instructions. If you have indeed filled the tanks full of fuel before calibration I am afraid you wont be calibrating the tanks with full tanks. Also, using someone else’s numbers on another type (RV10) will not provide accuracy for your tanks. I suggest that you drain your tanks and follow the instructions of filling 2 gallons at a time while setting the AUX numbers at each interval.

RVbySDI said:

As has been mentioned, follow the GRT instructions. If you have indeed filled the tanks full of fuel before calibration I am afraid you wont be calibrating the tanks with full tanks. Also, using someone else’s numbers on another type (RV10) will not provide accuracy for your tanks. I suggest that you drain your tanks and follow the instructions of filling 2 gallons at a time while setting the AUX numbers at each interval.

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+1. If you can’t store gas, burn (I mean fly) half off, and carefully drain one tank and move to the other, calibrate the empty tank 2 gal at a time. Do the other tank later. Also, I recommend the external bias resistors over the internal ‘pull down’ ones, for better accuracy. Make sure you have the grt instruction sheet for the calibration process, it’s in one of the Hx manuals somewhere. Not sure about the newer 10.1. Finally, the (Hx, at least) allows you to set up where you do the "gas added" input, after filling up; Either the EIS or the EFIS. I personally prefer the EIS for this (there's a shortcut, pushing 2 buttons at once), since my EIS is on the main buss and boots up as soon as I turn on the master - so I remember to update the fuel even before engine start. If I put the update capability on the EFIS, then I have to wait for it to boot up after engine start (it's on my avionics buss) and by then I usually forget!