B.  The floor mounted PDUs have numbers 1, 2, and 3 in the forward centerline, 4L through 7L, 17L through 19L2 in the left side, 4R through 7R,17R through 19R2, 23R, and 24 in the right side.
 C.  PDUs 2, 3, 4L(R) through 7L(R), 23R, and 24 are electrically steerable PDU. These PDUs steer automatically when control by the control panels.
 D.  PDUs 17L(R), 18L(R), 19L1(R1), and 19L2(R2), are retractable/steerable PDU. These PDUs are 90-degree steerable and also are able to retract electrically and manually.
 WARNING:  MAKE SURE THE PRESSURE OF THE WORN OUT/DEFECTIVE TIRE IS NOT MORE THAN 100 PSIG. IF THE PRESSURE OF THE WORN OUT/DEFECTIVE TIRE IS MORE THAN 100 PSIG, THE TIRE CAN EXPLODE. THE EXPLOSION CAN CAUSE INJURIES TO PERSONS OR DAMAGE RO EQUIPMENT.
 E.  Each floor mounted PDU consists of a wheel assembly driven by a rotary actuator. Some PDUs have a separate actuator for steering. Each PDU drive wheel actuator incorporates a spring-loaded brake which resists drive wheel rotation when the PDU is not operated. The brake is released magnetically when the PDU is energized.
 F.  The tray mounted system utilizes an average of three PDUs in place of a single floor mounted non-steerable PDU. These PDUs are spring loaded and remain in the raised position. Adequate vertical forces are applied by the use of the spring loads. This allows the PDU to be utilized for braking
 8.  Control Panels (Fig. 3)______________
 A.  The following cargo control panels are installed on the sidewalls of the main deck cargo compartment:
 (1)
Master cargo control panel (M30)

 (2)
Auxiliary cargo control panel (M5215)

 (3)
Side door cargo control panel (M1)

 (4)
Remote cargo control panel (M10)

 (5)
Local cargo control panel (M20 and M262)

 (6)
20 FT cargo control panel (M456)

 (7)
20 FT local cargo control panels (M611 and M612)

 B.  The master cargo control panel is the main control of the main deck cargo system.
 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 25-57-00
 ALL  ú ú 04B Page 13 ú Oct 18/01
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400 MAINTENANCE MANUAL
SEEC  SEEC
6R 7R 17R 18R5R
23R 123 19
4R
4L 5L 17L6L 7L 18L
SEE A
RED TRIGGER
DRIVE-WHEEL
FLAG

SEE B
PDU HANDLE
DRIVE-WHEEL
PDU ARROW
ACTUATOR

INDICATOR
LOCKPIN
PDU ELECTRICAL
CONNECTOR

DRIVE-WHEEL
DISENGAGE DRIVE-WHEEL DISENGAGE
CABLE SERRATED CABLE STOWAGE FITTING

INDEX BLOCK  (UNDER FLOOR)
INDEX 1 PLATE DRIVE-WHEEL ACTUATOR DRIVE-WHEEL NONSTEERABLE PDU DISENGAGE HANDLE
(FIXED AND MANUALLY ADJUSTABLE)
PDU TORQUE REACTION
A
FITTING (2 LOCATIONS)
STEERING
ACTUATOR

SINGLE STUD DUMMY CONNECTOR
(DOUBLE STUD ON AND COVER
OTHER FITTING) (3 LOCATIONS)
ELECTRICAL CONNECTOR LOCK BOLT
STUD FITTING (2 LOCATIONS) ELECTRICAL
PLUG (P1)
WIRE BUNDLE FOR CONNECTOR
DRIVE-WHEEL ACUATOR PLUG (P3) WIRE BUNDLE FOR ELECTRICAL
STEERING ACTUATOR CONNECTOR PLUG (P2) FWD
ANTI-ROTATION WIRE BUNDLE FOR SUPPORT FITTING LIMIT SWITCHES (2 LOCATIONS)
LEGEND
RETRACTABLE/STEERABLE PDU INBD NONSTEERABLE PDU
B
RETRACTABLE/STEERABLE PDU
MANUALLY ADJUSTABLE PDU ONLY
Power Drive Units
Figure 2 (Sheet 1)

L50235
 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 25-57-00
 ALL  ú ú 04B Page 14 ú Oct 18/00
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400
MAINTENANCE MANUAL

POWER
DRIVE

TRAY MOUNTED PDU

Power Drive Units
Figure 2 (Sheet 2)

EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 25-57-00
 ALL  ú ú 04B Page 15 ú Oct 18/00
　
中國航空網 m.k6050.com
航空翻譯 www.aviation.cn
本文鏈接地址：747-400 AMM 飛機維護手冊 EQUIPMENT/FURNISHINGS 2(44)