31-61-00
 ALL  ú ú 28 Page 82P ú Feb 18/02
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
C20024
A
747-400
MAINTENANCE MANUAL

 (2)  
Total Fuel Quantity

 (a)  Total fuel quantity is indicated by a white colored digital readout. The associated caption indicates whether pounds (LBS) or kilograms (KGS), multiplied by 1000, will be used as the display units. During fuel jettison, the preselected total fuel will be displayed below the total fuel quantity. This preselected value is the amount of fuel to remain after jettison.

 (3)  
Main and Center Tank Quantity

 (a)  Main and center tank fuel quantity data is displayed by white colored digital readouts enclosed in boxes. If fuel quantity in main tanks 1, 2, 3 or 4 falls below 2000 lb, the readout will change from white to amber in color. If there is a fuel imbalance between main tanks 1 and 4 or main tanks 2 and 3, the color of the boxes enclosing the associated digital readouts will change from white to amber.

 (4)  
Reserve Tank Quantity

 (a) Fuel quantity data for reserve tanks 2 and 3 is displayed by white colored digital readouts enclosed in "open" boxes.

 (5)  
Crossfeed Valve Positions

 (a)  Crossfeed valve 1 through 4 positions are displayed by a symbol consisting of two parallel lines within a circle. If the valve is open, the two parallel lines overlay the fuel line. If the valve is closed, the parallel lines are perpendicular to the fuel line. If the valve position agrees with the crossfeed valve position switch, the symbol is colored white. If the crossfeed valve position does not agree with the crossfeed valve position switch, the symbol is colored amber.

 (6)  
Fuel Pump Status

 (a)  Fuel pump status is indicated by square box symbology. A PUMP OFF symbol is indicated by a square box. A PUMP ON symbol is indicated by two vertical lines enclosed by a box . A PUMP ON
 -FLOW symbol is indicated by an illuminated flow bar segment enclosed by a box. If fuel pump data becomes invalid, a low intensity white box is displayed in place of the associated pump symbol.
 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 31-61-00
 ALL  ú ú 30 Page 82Q ú Feb 18/02
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400
MAINTENANCE MANUAL

 (b) Main Tank Main Pumps
 1)  Forward and aft main tank main pump symbology is presented for main tanks 1 through 4. The following table represents the display logic for these fuel pumps.
 ~......................................................... | FORWARD AND AFT MAIN TANK MAIN PUMPS | ........................................................... | PUMP | PUMP | FLOW | PUMP | SYMBOL | SYMBOL | | SWITCH | PRESSURE | TO | STATUS | DISPLAYED| COLOR | | IS ON | IS LOW | ENGINES| | | | ........................................................... | YES | NO | YES | ON-| PUMP ON- | GREEN | | | | | FLOW | FLOW | | ........................................................... | YES | NO | NO | ON-| PUMP ON | GREEN | | | | |PRESSURE| | | ........................................................... | YES | YES | N/A | ON-LOW | PUMP ON | AMBER | | | | |PRESSURE| | | ........................................................... | NO | N/A | N/A | OFF | PUMP OFF | WHITE | 2........…..........…........…........…..........…........1
 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 31-61-00
 ALL  ú ú 07 Page 82R ú Jun 15/98
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400 MAINTENANCE MANUAL
 (c) Main Tank Override Pumps
 1)  Forward and aft main tank override pump symbology is presented for main tanks 2 and 3. The following table represents the display logic for these fuel pumps.
　
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 指示/記錄系統 2(73)