MGL Avionics User Forum

Hello.

I've been testing and calibrating the fuel level sender. It's a 240-33 Ohm one and I have a behaviour I don't know if it's right.

Header tank is 7 liters and I get these values every 500 ml (ml:raw value):

0: 3908
500: 3908
1000: 3908
1500: 3908
2000: 3908
2500: 3908
3000: 3908
3500: 3908
4000: 3908
4500: 3908
5000: 3908
5500: 2730
6000: 2730
6500: 1938
7000: 1938
7300: 1930

The value only changes twice. Fron 0 to 5 liters, the raw value is always the same.

I have an analogue indicator too and it changes continuosly.

Any hint about this behaviour?

Thank you.

Connections are as follow:

Hello.
Disconnect the analog indicator. It is forcing about 6V to the RDAC FL input through it's internal resistor bridge

Is the Fuel Level Pull Up resistor enabled on the DIP switch?

Hi.

I've tried both positions for FL1 DIP switch.

Olivier wrote: ↑Sat Jun 29, 2024 2:30 pm Hello.
Disconnect the analog indicator. It is forcing about 6V to the RDAC FL input through it's internal resistor bridge

Oops.

I didn't saw your answer. I'll try tomorrow. Thank you.

Solved.

I installed a switch to select one or other level gauges. Normally connected to Efis and the analog one as a backup/check.

Regards. Manolo.