G900X/G950 Installation and Maintenance Manual – GEA 71
Revision D
190-00719-00
Page 5-22
5.6.2.9 Fuel
Flow
Sensor
Sensor Description:
Floscan 201B-6 turbine fuel flow sensor. The sensor produces a current pulse signal from an opto-
electronic pickup with a preamplifier.
General Installation Guidance:
The below is taken from the Floscan Series 200 Flow Transducer Application Notes:
1.
The inlet and outlet ports in series 200 flow transducers have ¼” NPT threads. Use only ¼” NPT
hose or pipe fittings to match. When assembling fittings into the inlet and outlet ports, DO NOT
EXCEED a torque of 15 ft. lbs. (180 inch lbs.), or screw the fittings in more than 2 full turns past
hand tight WHICHEVER HAPPENS FIRST. Floscan Instrument Co., Inc. will not be
responsible for cracked castings caused by failure to use ¼” NPT fittings, over torquing the
fittings, or assembling them beyond the specified depth.
2.
A screen or filter should be installed upstream of the flow transducer to
screen out debris which
could affect rotor movement or settle in the V-bearings. As turbulence upstream of the transducer
affects its performance, there should be a reasonable length of straight line between the
transducer inlet and the first valve, elbow, or other turbulence producing device.
3.
Install the flow transducer with wire leads pointed UP to vent bubbles and insure that the rotor is
totally immersed in liquid. For maximum accuracy at low flow rates, the transducer should be
mounted on a horizontal surface.
Some additional mounting considerations should be noted as follows:
1.
When installing the NPT fittings into the transducer, use fuel lube such as EZ TURN © or an
equivalent thread sealer. Teflon tape should NEVER by used in a fuel system.
2.
To minimize inaccuracies caused by turbulence in the fuel flow, the sender should be mounted
with approximately 5-6” of straight tubing before and after the sender. If special circumstances
exist that prevent an extended length of straight tubing before and after the sender, then a gently
curved hose may be acceptable. 45 degree or 90 degree elbow fittings should NOT be used
immediately before or after the sensor.
3.
Specific sender mounting location is left to the builder. Ideally, the sender should be placed prior
to the fuel distribution device (carburetor or fuel injection distribution device). On a Continental
fuel injected engine, the transducer must be located between the metering unit and the flow
divider valve.
4.
Sensor wires should be connected to the appropriate inputs on the GEA as referenced in the
G900X/G950 interconnects in Appendix F-J.
When installing the sender, the builder should take note of the 16-XXXX number on the tag attached to
the unit. The “XXXX” refers to the calibrated K factor of the sender, and it will be used in Section 15 to
calibrate the G900X/G950 for the specific sender installed.
