曝光臺 注意防騙 網曝天貓店富美金盛家居專營店坑蒙拐騙欺詐消費者

 C.  The electric motor-driven actuator is identical to the one used on the reserve tank transfer valve.
 D.  The valve body consists of a valve housing, rotating-type valve disk, a universal splined connector to mate with the adapter shaft from the actuator, a flanged fitting on the outboard end, and provisions for attaching a coupling nut on the inboard end. A permanent alignment mark on the outside of the valve housing indicates the element position in the shutoff position. Operation of the valve can be verified by monitoring the manual override lever when power is applied to the valve.
 E.  The adapter/shaft assembly is similar to the one used on the reserve tank transfer valve except that the main tank transfer valve requires a longer shaft.
 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 28-16-00
 ALL  ú ú 01 Page 6 ú Feb 15/99
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400
MAINTENANCE MANUAL

 7.  Main Tank Transfer Valve Control Switch (Fig. 1)
_______________________________________
 A.  The main tank transfer valve control switch provides an alternate control to the fuel jettison control card for supplying 28-volt dc power to the main tank transfer valves. The switch is located on the miscellaneous switch module on the pilots' overhead panel and is identified as FUEL XFER MAIN 1&4.
 B.  When the switch is operated, the word ON is displayed on the switch to indicate that the valve has been commanded open.
 8.  Operation (Fig. 2)
_________
 A.  Functional Description
 (1)  
Reserve Tank to Inboard Main Tank Fuel Transfer (Fig. 3)

 (a)  
Reserve tank transfer valve operation is controlled automatically by the fuel system management card (FSMC). The FSMC receives fuel level signals from the fuel quantity processor unit and the single point sensors in the inboard main tanks. When the fuel quantity in either inboard main tank decreases to 6,000 gallons (22,700 liters), the FSMC provides an electrical ground for the reserve tank transfer valve control relays. When the relays are energized, power is supplied to all four reserve tank transfer valves, causing the valves to drive to the open position. 1) The FSMC monitors the actual position of the reserve tank

 transfer valves as indicated by the valve position logic cards. If the actual valve positions for both transfer valves in the same tank disagree with their commanded valve positions, a valve disagreement advisory (FUEL RES 2 XFR or FUEL RES 3 XFR) is displayed on the main EICAS screen. If the actual valve position of any single transfer valve disagrees with its commanded position, a status message for that valve is recorded. The status message is displayed on the auxiliary EICAS screen when the STAT button is pressed.

 (b)  
During transfer operation, colored bars illuminate on the EICAS fuel synoptic, indicating reserve-to-main tank fuel transfer (Fig. 5).

 (c)  
When the fuel management system determines that the airplane is on the ground, the electrical grounds through the FSMC are removed. The control relays become de-energized and power is supplied to drive the valves to the closed position.

 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 28-16-00
 ALL  ú ú 02 Page 7 ú Feb 15/99
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400
MAINTENANCE MANUAL

NO. 2 RESERVE TANK
Reserve and Main Tank Interconnection Flow Diagram
Figure 2

EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 28-16-00
 ALL  ú ú 01 Page 8 ú Feb 10/92
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400
MAINTENANCE MANUAL

EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú
　
中國航空網 www.k6050.com
航空翻譯 www.aviation.cn
本文鏈接地址：747-400 AMM 飛機維護手冊 燃油 FUEL 1(177)