Electronics International FL-1 - Manual (Page 24)

4. As you lower the sensor float slightly slightly slightly slightly slightly from the top of the tank, the resistance should start to
increase. If it does not, the sensor resistance is probably bottomed out. The FL-2 will read
lower than actual fuel levels until the sensor wiper drops onto the resistive element.
With the sensor float held to the top of the tank, adjust the sensor float arm so the wiper is
on the resistive element and not on the termination (end stop). You will need an ohmmeter
to determine this. As you slightly move the float arm, the resistance should change.
B. For resistive fuel sensors that increase resistance when fuel is added perform the following tests:
1. With the float at the bottom of the tank (as it would be if the
tank was empty), measure the resistance of the fuel sensor .
The resistance should measure 1/4 or less of the total sensor
resistance. If the readings are higher, you may need to adjust
the sensor float arm. Prior to doing this, read tests 3 and 4
below.
2. With the float at the top of the tank (as it would be if the tank
was full), measure the resistance of the fuel sensor. The resis-
tance should be between 270 ohms and 90 ohms. If the read-
ings are below 90 ohms or greater than 270 ohms, you may be
using the wrong type of sensor. Use a sensor that increases
resistance when fuel is added and has a maximum resistance of between 90 and 270 ohms.
3. As you raise the sensor float slightly slightly slightly slightly slightly off the bottom of the tank, the resistance should start to
increase. If it does not, the sensor resistance is probably bottomed out. The FL-2 will read
lower than actual fuel levels until the sensor wiper drops onto the resistive element.
With the sensor float held to the bottom of the tank, adjust the sensor float arm so the wiper
is on the resistive element and not on the termination (end stop). You will need an ohmme-
ter to determine this. As you slightly move the float arm, the resistance should change.
4. As you lower the sensor float slightly slightly slightly slightly slightly from the top of the tank, the resistance should start to
decrease. If it does not, the sensor resistance is probably topped out. The FL-2 will read
lower than actual fuel levels until the sensor wiper drops onto the resistive element.
With the sensor float held to the top of the tank, adjust the sensor float arm so the wiper is
on the resistive element and not on the termination (end stop). You will need an ohmmeter
to determine this. As you slightly move the float arm, the resistance should change.
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