fuel Quantity calibration
Posted: Tue Jun 19, 2018 4:21 pm
Gentlemen and or Ladies,
New member here. I share Walkman's sentiments. Allow me to explain and seek your help.
I own a RV9A and am in he process of upgrading my panel to full IFR capability. Have the following equipment installed and integrated with GRT products:
GRT HXr 8.4 EFIS
GRT Mini GA EFIS
GRT 4000 EIS
PSE PMA 6000b Audio Panel
Val Com 2000
Val Com 2KR remoted
Val Nav 2KR remoted
Garmin GPS 400WAAS
Garmin GTX 330es
TruTrak Autopilot
Was hoping to have this aircraft flying months ago but am continually frustrated by a number of nitpicking issues, fuel qty indication being the principal one for I cannot fly the aircraft without a fuel qty indicating system. Just so you'll know, I originally had my fuel qty, fuel pressure, and electrical load (Auxes 1-4) wired through the 4000 EIS and one wire from the EIS control module integrated with my HXr EFIS via a serial port.
After finding out about this Forum, registering, and seeing Walkman's comments I couldn't help but say "Yeah, somebody else shares my feelings on this issue as well." Since then I've taken my L and R fuel qty float resistor sensors out of the 4.8V excitation and 470 Ohm pull up resistor circuit, and wired the float resistors directly to the HXr EFIS via Analog inputs without the 470 ohm pull up resistor.
I have gone through the calibration procedures per instructions in the supplement identified on this forum with negative results. Checked my L tank and the float resistor reads 30 Ohms with a full tank (18 gal); Emptied my L tank. Checked the float resistor and it reads 248 Ohms tank empty. Went through the HXr EFIS Analog setup procedures and configured both tanks per instructions - very easy and simple. When I started adding fuel to the L tank, the bar graph read 182 gal or maybe it was 82, regardless, I continued to add fuel until I eventually had 5 gal and all the graph did was fluctuate between 182 and 183. I stopped fueling and checked the resistance on my float resistor and it read 143 ohms, clearly indicating that the float resistor is working properly.
Prior to going through this procedure, I went back to my EIS control module and the Set Configuration procedure for Aux 1 and 2, and zeroed out the SF and Offset just to make sure those numbers, via 232 serial interface didn't conflict with the analog signals directly from the sensors.
So, here I am still pulling out my rapidly thinning hair trying to get this system to work to no avail. I figured if I can't get the L tank indicating system to work properly so why bother with the R tank.
Any suggestions would be greatly appreciated.
George
New member here. I share Walkman's sentiments. Allow me to explain and seek your help.
I own a RV9A and am in he process of upgrading my panel to full IFR capability. Have the following equipment installed and integrated with GRT products:
GRT HXr 8.4 EFIS
GRT Mini GA EFIS
GRT 4000 EIS
PSE PMA 6000b Audio Panel
Val Com 2000
Val Com 2KR remoted
Val Nav 2KR remoted
Garmin GPS 400WAAS
Garmin GTX 330es
TruTrak Autopilot
Was hoping to have this aircraft flying months ago but am continually frustrated by a number of nitpicking issues, fuel qty indication being the principal one for I cannot fly the aircraft without a fuel qty indicating system. Just so you'll know, I originally had my fuel qty, fuel pressure, and electrical load (Auxes 1-4) wired through the 4000 EIS and one wire from the EIS control module integrated with my HXr EFIS via a serial port.
After finding out about this Forum, registering, and seeing Walkman's comments I couldn't help but say "Yeah, somebody else shares my feelings on this issue as well." Since then I've taken my L and R fuel qty float resistor sensors out of the 4.8V excitation and 470 Ohm pull up resistor circuit, and wired the float resistors directly to the HXr EFIS via Analog inputs without the 470 ohm pull up resistor.
I have gone through the calibration procedures per instructions in the supplement identified on this forum with negative results. Checked my L tank and the float resistor reads 30 Ohms with a full tank (18 gal); Emptied my L tank. Checked the float resistor and it reads 248 Ohms tank empty. Went through the HXr EFIS Analog setup procedures and configured both tanks per instructions - very easy and simple. When I started adding fuel to the L tank, the bar graph read 182 gal or maybe it was 82, regardless, I continued to add fuel until I eventually had 5 gal and all the graph did was fluctuate between 182 and 183. I stopped fueling and checked the resistance on my float resistor and it read 143 ohms, clearly indicating that the float resistor is working properly.
Prior to going through this procedure, I went back to my EIS control module and the Set Configuration procedure for Aux 1 and 2, and zeroed out the SF and Offset just to make sure those numbers, via 232 serial interface didn't conflict with the analog signals directly from the sensors.
So, here I am still pulling out my rapidly thinning hair trying to get this system to work to no avail. I figured if I can't get the L tank indicating system to work properly so why bother with the R tank.
Any suggestions would be greatly appreciated.
George