(5)  
When the BCU-1 receives the bus isolation request from an FCC, the BCU-1 examines the status of these items and opens or closes relays, as necessary, to isolate the three power sources. As an example, with all generators and transformer-rectifiers operating BTB 1, 2 and 3 will open and DCIR 2 and 3 will open when the bus isolation is requested.

 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 22-11-00
 ALL  ú ú 04 Page 5 ú Oct 10/92
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A

747-400
MAINTENANCE MANUAL

BUS ISOLATE REQUEST
G10 BUS CONT UNIT-1
G11 BUS CONT UNIT-2
B7079 FLT CONT CMPTR-RIGHT
B7078 FLT CONT CMPTR-CENTER
AFDS Autoland Bus Isolation
Figure 3

EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 22-11-00
 ALL  ú ú 02 Page 6 ú Oct 10/92
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A76993
A
747-400
MAINTENANCE MANUAL

 (6)  
These are the conditions for the bus isolation to occur:

 (a)  
The approach (APP) mode is armed.

 (b)  
All the autopilot channels are armed, or engaged.

 (c)  
All the autopilot channels are not NO LAND 3 and not NO AUTOLAND (the main EICAS display does not show NO LAND 3, or NO AUTOLAND).

 (d)  
The airplane is above the alert height.

 (7)  
The bus isolation will be cancelled if one of these conditions occurs:

 (a)  
The airplane is above the alert height and if any autopilot channel has determined a NO LAND 3, or NO AUTOLAND.

 (b)  
All the autopilots disconnect.

 (c)  
The go-around has been initiated.

 (8)  
If the bus isolation does not occur within 4 seconds of the bus isolate request, the request is cancelled and the autopilot goes to NO LAND 3 condition.

 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 22-11-00
 ALL  ú ú 03 Page 7 ú Jun 10/93
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400 MAINTENANCE MANUAL
 FLIGHT CONTROL COMPUTER - REMOVAL/INSTALLATION
______________________________________________
 1.  General_______
 A.  This procedure contains two tasks. The first task is for the removal of the Flight Control Computer (FCC). The second task is for the installation of the FCC.
 B.  You can find the three FCCs in the main equipment center. The left FCC (B7077) is on the No. 1 shelf of the E1 electronics equipment rack. The center FCC (B7078) is on the No. 3 shelf of the E1 electronics equipment rack. The right FCC (B7079) is on the No. 4 shelf of the E1 electronics equipment rack.
 TASK 22-11-01-004-026
 2.  Remove The Flight Control Computer__________________________________
 A.  References
 (1)  
06-09-01/201, Body Section 41 Access Doors and Panels

 (2)  
20-11-22/401, Rack-Mounted Electrical/Electronic Module

 (3)  
IPC 22-11-01, Fig. 2

 B.  Access
 (1)  
Location Zones 117 Electrical and Electronics Compartment, LH 221 Control Cabin, LH 222 Control Cabin, RH

 (2)  
Access Panel
 117AL Electronics Compartment Access Door

 C.  Remove the Flight Control Computer
 S 864-027
 (1) Open these circuit breakers and attach the DO-NOT-CLOSE tags:
 (a)  P7 Overhead Circuit Breaker Panel
 1) 7E9, MCP L
 2) 7E18, MCP R

 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 22-11-01
 ALL  ú ú 01 Page 401 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 空調 AUTO FLIGHT(75)