TruTrak EMS BU (8300-065) - Manual (Page 13)

TruTrak Flight Systems 11 EMS Installation Manual
JUNE 2009 8300-065 Rev D
Fuel Flow Sensor (8250-041)
The FloScan fuel flow transducer has ¼” female NPT threads at both
the inlet and outlet. Only use ¼” NPT fittings to match. When
installing, do not screw fittings more than two full turns past hand
tightened. The torque should not exceed 180 inch-lbs.
WARNINGS:
Due to vibration issues, never connect the sensor directly to engine.
Do NOT use Teflon tape when screwing in any of the fittings.
Make note of the K factor number on the tag attached to the fuel flow sensor. You will need it in the Fuel
Flow Configuration section. Do not lose this number, the fuel flow calibration will not be correct without
this setting.
Setting K factor:
Press and hold the right knob, wait for “SETUP” to show in center lower display press button below at the
same time you are holding the knob. Press and release “CONFIG” press and release “FLOW”, then
“YES”, set K factor by rotating right knob. Press and rotate to step in 100 increments.
General Placement Recommendations
When placing the sensor, ensure that the three wire leads are pointed straight up. Ensure that the
transducer has 6” of straight fuel line before and after it. Placement of the fuel flow sender relative to
other items in the fuel system like fuel pumps is left to the builder. The manufacturer of the fuel flow
sender does not make strong recommendations on this point. It is not uncommon, though, to place the
sender downstream of any auxiliary electric boost pumps but upstream of the engine driven fuel pump.
For best measuring performance, the fuel should travel uphill by one to two inches after leaving the fuel
flow sender.
Fuel Level Sensor
The EDM supports both resistive type sensors as well as capacitive sensors, which output a voltage (e.g.,
Princeton). Once you have installed your fuel level sensors, you will need to calibrate each of them, as
described in Fuel Level Calibration.
Resistive Fuel Level Sensor
You may connect up to two resistive fuel level sensors to the EDM. Simply connect the output of the
sensor you would like to be Fuel Level 1 (right tank) to pin 26 and the sensor you would like to be Fuel
Level 2 (left tank) to pin 8, perform calibration.