MGL Avionics Stratomaster Ultra “L” Owner’s manual
Page 56
The calibration procedure should be carried out with your aircraft in flight attitude. This means
you need to lift the tail if you have a tail-dragger or lift the nose wheel if you have a
weightshift trike. You start the calibration procedure with an empty tank.
Your first determination should be how much reserve fuel you should carry. Reserve fuel
would be fuel that is not taken into account by the fuel level sender. We recommend at least
10% of your fuel tank capacity as reserve fuel, preferably even more.
To illustrate the calibration procedure, let us assume we have a weightshift trike with a tank
capacity of 50 liters without reserve.
We decide to use a five-liter reserve, leaving us with a usable fuel capacity of 45 liters.
Our first step is now to enter this capacity into the instrument. Use the “prev” and “next” keys
to move the highlight to the “fuel tank capacity” item. Then use the + and – keys to set the
entry to read 45 liters.
Our next step would be to raise the nose gear of the trike to flight position. An upturned
bucket or similar item is normally all that is required.
We now start with the empty tank. Add five liters of fuel (our reserve quantity) using a suitable
measure. Make sure the measure is suitably accurate.
This is now the “level sender reading at 0 Lt” position. Move the highlight to this position and
wait until the sender reading has stabilized (You will see the sender reading at the top line).
This could take up to a minute so have patience.
Should this number not react to changes of your level sender position, then you have a
problem. Please check your wiring according to the installation section of this manual.
If you see the number changing then everything is well. Once it has stabilized and the
highlight is on the 0 Lt position, press the “select” key to transfer the reading from the sender
to the calibration point.
Now you are ready for the next step. Add the required amount of fuel to get to the next level
(In our case 9 Lt – this is 20% tank capacity). Once done, wait for the reading to stabilize and
press “select” again after you have moved the highlight to the “9 Lt” position.
Proceed in a similar manner until you have reached the last calibration position at 100% tank
capacity.
You are done !
Press “Menu” to exit this function. This will write the new calibration to permanent memory in
the instrument. You can repeat this calibration many times so do not worry if you do not get it
right the first time.
The instrument uses the 6 calibration points to work out a correction curve that takes into
account the tolerances of your fuel level sender and the shape of your fuel tank. This results
in an incredibly accurate and usable fuel level display that far exceeds that available from
ordinary dial type gauges.
Note:
The calibration positions may be edited by using the + and – keys. This allows you, in theory,
to copy calibration settings from one instrument to another. We however recommend that you
do go though the calibration procedure even if the two aircraft are identical in all respects.
Tolerances do exist and the calibration cancels these out.
Accurate fuel level displays are a vital safety factor for an aircraft and a very useful feature for
peace of mind during cross county flights.
