(2)
the electronic speed switch
(3)
the sequencing oil pressure switch (referred to as the sequencing switch for the oil pressure)
(4)
the low oil pressure switch (referred to as the oil pressure switch)
(5)
the high oil temperature switch (referred to as the oil temperature switch)
(6)
the compressor inlet temperature sensor (Airplanes with the ETC)
(7)
the electronic temperature control (referred to as the ETC) (Airplanes with the ETC).
B. AIRPLANES WITHOUT THE ETC; The APU control thermostat supplies additional control. For a more detailed description of the APU control thermostat, refer to AMM 49-31-00/001 and AMM 49-52-00/001.
C. AIRPLANES WITH THE ETC; The proportional control valve supplies additional control. For a more detailed description of the proportional control valve, refer to AMM 49-52-00/001.
D. The APU control unit is the main control for the APU operation. The APU control unit is found on the E3-3 electrical shelf in the electronics bay. The APU control unit has a sequence of events for the APU start and the APU operation. The APU control unit gives protection to the APU for overspeed, high oil temperature and low oil pressure.
E. The sequencing switch for the oil pressure permits the fuel and ignition to be supplied to the APU engine at the correct time during the APU start. The electronic speed switch stops the operation of the starter motor and ignition at the correct time during the APU start. Also, the electronic speed switch prevents the use of bleed air until the APU engine speed is 95% and keeps the APU engine from an overspeed. The oil pressure switch and oil temperature switch stop the APU if the oil temperature or oil pressure do not stay in the limits.
2. APU Control Unit (Fig. 1)
________________
A. The APU control unit starts, operates and stops the APU. The APU control unit is installed in the lower section on the E3-3 electrical shelf. There is a circuit breaker on the face of the APU control unit.
EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú
49-61-00
ALL ú ú 01 Page 1 ú Jul 12/00
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
////////////////////////A / GTCP85-129 SERIES /737-300/400/500/ ENGINES /MAINTENANCE MANUAL ////////////////////////
"TEST PASS" AND "TEST FAIL" LIGHTS
APU Control Component Location Figure 1 (Sheet 1)
A09877
EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú
49-61-00
ALL ú ú 02 Page 2 ú Mar 15/92
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
APU Control Component Location
Figure 1 (Sheet 2)
EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú
49-61-00
ALL ú ú 01 Page 3 ú Oct 20/83
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
////////////////////////A / GTCP85-129 SERIES /737-300/400/500/ ENGINES /MAINTENANCE MANUAL ////////////////////////
SEE A
SEE B
A
OIL
TEMPERATURE
SWITCH
SEQUENCING SWITCH FOR THE OIL PRESSURE FWDSWITCH FOR THE LOW OIL PRESSURE
B
APU Control Component Location
Figure 1 (Sheet 3)
EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú
49-61-00
ALL ú ú 01 Page 4 ú Mar 15/92
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：737-300 400 500 AMM 飞机维护手册 AIRBORNE AUXILIARY POWER 2(103)
