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73-21-00
ALL ú ú N08 Page 14 ú Jun 18/00
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
7) FMU resolver excitation
8) FMU resolver input
9) External reset
10) Torque motor output for the 2.5 bleed valve actuator
11) Torque motor output for the engine air/oil heat exchanger
valve
(c)
J7ENG 1) TT2 input 2) TT3 input 3) TT4.95 input 4) Scavenge oil temperature input for the No. 3 bearing 5) Engine oil temperature input 6) Fuel temperature input 7) LVDT excitation for the Stator vane actuator 8) LVDT input for the stator vane actuator 9) TCC LVDT excitation 10) TCC LVDT input 11) RVT excitation for the 2.5 bleed valve actuator 12) RVT input for the 2.5 bleed valve actuator 13) RVT excitation for the engine air/oil heat exchanger valve 14) RVT input for the engine air/oil heat exchanger valve 15) Thrust reverser LVDT input 16) Thrust reverser LVDT excitation
(d)
J8PWR
1) HPC secondary flow control (left) valve and IDG air/oil
heat exchanger valve override solenoid power output 2) TVBCA solenoid power output 3) 28 volts dc ground test power input 4) Overspeed solenoid output 5) 28 volts ac power input (N2 signal) for the EEC alternator 6) Power output for the start bleed solenoid 7) Power output for the stability bleed solenoid 8) Power input for the 28 volts dc performance solenoid 9) Power output of the bypass valve solenoid for the fuel/oil
cooler
10) ALTN mode indication light driver
11) Thrust reverser interlock relay driver
(2)
Four of the electrical connectors on the aft side of the EEC (J1A/F, J2FCU, J3ENG, and J4PWR) are for the channel B inputs and outputs that follow [the fifth electrical connector (J9DEP) is for the data entry plug]:
(a)
J1A/F (same as J5A/F with the addition of an analog N1 output)
(b)
J2FCU
1) N1 input
2) Position discrete for the HPC secondary flow control
(right) valve 3) Torque motor output for the stator vane actuator 4) TCC torque motor output 5) FMU torque motor output 6) FMU resolver excitation 7) FMU resolver input
EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú
73-21-00
ALL ú ú N02 Page 15 ú Feb 10/93
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
////////////////////////A / PW4000 SERIES /747-400 / ENGINES/MAINTENANCE MANUAL ////////////////////////
8) External reset
9) Torque motor output for the 2.5 bleed valve actuator
10) Torque motor output for the engine air/oil heat exchanger
valve
(c)
J3ENG (same as J7ENG)
(d)
J4PWR 1) HPC secondary flow control (right) valve solenoid, IDG
air/oil heat exchanger valve power output 2) 28 volts dc ground test power input 3) Overspeed solenoid output 4) 28 volts ac power input (N2 signal) for the EEC alternator 5) Power output for the start bleed solenoid 6) Power output for the stability bleed solenoid 7) Power input for the 28 volts dc performance solenoid 8) Power output of the bypass valve solenoid for the fuel/oil
cooler 9) ALTN mode indication light driver 10) Thrust reverser interlock relay driver
3. Fuel Metering Unit (FMU) (Fig. 1 and 3)
________________________
A. The FMU supplies the functions that follow:
(1)
Controls the quantity of fuel flow to the fuel injectors as scheduled by the EEC
(2)
Controls minimum and maximum fuel flow
(3)
Supplies fuel shutoff function
(4)
Bypasses fuel during engine windmilling
(5)
Supplies fine filtered servo fuel pressure for hydromechanical valves and actuators
B.
The FMU is installed directly to the forward end of the fuel pump. The fuel pump is installed on the forward face of the main gearbox at the 5 o'clock position.
C.
The FMU includes the primary components that follow:
(1)
Servo filter
(2)
Pressure regulating valve
