POWERPLANT
AIRPLANE
OPERATIONS
MANUAL
2-10-35
Page
2
Code
01
REVISION 23
FUEL TEMPERATURE SENSOR
The engine fuel-temperature sensor has an indication range of -54° to
176°C (-65° to 350°F) and is located on the FCOC. A caution message
is presented on the EICAS in case of fuel low temperature (below 5°C
in the engine).
ELECTRICAL FUEL-FILTER IMPENDING-BYPASS INDICATOR
The engine electrical fuel-filter impending-bypass indicator is located
on the engine fuel pump and metering unit (FPMU). An advisory
message is presented on the EICAS if the differential pressure across
the filter exceeds its set point.
MAGNETIC INDICATING PLUG
The magnetic indicating plug is located in the oil tank. The magnetic
plug contacts are normally open and are electrically closed when
conductive material bridges the gap between them.
IGNITER SPARK-RATE DETECTOR
The engine igniter spark-rate detectors are outputs from the ignition
exciters that indicate that an electric field has collapsed in the exciter
circuit. A signal is available for each igniter circuit on the engine.
VIBRATION SENSORS
The engine vibration sensors are accelerometers that detect abnormal
fan rotor and turbine rotor vibration. The transducers are connected
through the engine wiring harness to the EICAS.
FUEL FLOWMETER
The fuel flowmeter is a turbine, mass flow sensor. A given fuel flow
through the sensor causes the turbine to move to a calibrated position,
providing a specific voltage output to the Data Acquisition Unit (DAU).
The DAU converts the voltage signal from the sensor into a flow-rate
value (pounds or kilograms per hour) for cockpit display. The fuel
flowmeter is calibrated for a range between 130 to 4300 pph. During
some starts, fuel flow may drop to values out of the flowmeter range. In
this case a zero fuel flow will be displayed on EICAS for a few
seconds.
To Next Page
