(a)
Do the initial latches open switch adjustment as follows:
NOTE: Use this procedure if you will adjust a replaced switch.
____ If you will adjust the initial switch, go to the switch operational check.
1) With the door closed, loosen the locknuts and adjust the switch in the bracket to get the initial positions (View A-A).
CAUTION:_______IN CASE THE DOOR DOES NOT OPEN, STOP IMMEDIATELY. DO NOT OPERATE THE DOOR CONTROL SWITCH. HOLDING THE DOOR CONTROL SWITCH MAY DAMAGE THE ACTUATOR. WAIT AT LEAST 1 MINUTE BEFORE SECOND ATTEMPT. IF THE DOOR STILL DOES NOT OPEN, WAIT AT LEAST 10 MINUTES BEFORE THIRD ATTEMPT.
2) Open the door 1 to 2 feet.
3) Set the latch actuator in the external stops open position as follows: a) Use a torque wrench with a dial indicator to manually
turn the actuator counterclockwise at 25 |5 pound-inches. b) Find the position at which the torque increases by 15-20 pound-inches. c) Turn the torque wrench 1/2 turn clockwise.
NOTE: This is when the external stops are against each
____
other.
d) Make sure the plunger for the latches open switch is
not fully pushed in. 4) Turn the latch actuator 15 turns clockwise. 5) Make sure the striker plate does not touch the switch
plunger. 6) Disconnect electrical connector DX225C from the cargo door junction box.
EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú
52-32-00
ALL ú ú 04 Page 548 ú Jun 15/98
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
(b)
A
747-400 MAINTENANCE MANUAL
7) As you turn the latch actuator 8 |1/4 turns counterclockwise (switch actuates 7 |1/4 turns prior to external stops [open] position [Fig. 502]), adjust the switch to get a continuity between pins 21 and 22 of connector DX225C.
NOTE: The switch must operate as the latch actuator is
____ turned to the open stops (counterclockwise). One turn of the limit switch locknut will change the switch operation point approximately one turn on the latch actuator.
8) Connect electrical connector DX225C to the cargo door junction box.
9) Turn the latch actuator counterclockwise to the fully open position before you operate the door.
Do the operational check of the latches open switch as follows:
1) Fully close the door.
CAUTION:_______IN CASE THE DOOR DOES NOT OPEN, STOP IMMEDIATELY. DO NOT OPERATE THE DOOR CONTROL SWITCH. HOLDING THE DOOR CONTROL SWITCH MAY DAMAGE THE ACTUATOR. WAIT AT LEAST 1 MINUTE BEFORE SECOND ATTEMPT. IF THE DOOR STILL DOES NOT OPEN, WAIT AT LEAST 10 MINUTES BEFORE THIRD ATTEMPT.
2) Open the door electrically approximately 1 to 2 feet (until the latch operation stops).
NOTE: You must open the door electrically since the latch
____ position at the electrical shutoff finds if the position of the switch is acceptable.
3) Use a torque wrench with a dial indicator to apply 25 |5 pound inches to the manual drive of the latch actuator in the counterclockwise direction.
4) Carefully count the number of turns that remain until the external stops are touched (Fig. 510).
NOTE: The external stops must be touched in 3 |1 turns.
____
5) If the external stops are not touched in 3 |1 turns, do these steps: a) Subtract the actual number of turns that remain from the 3 turns. b) Subtract this difference from 8 |1/4 turns.
EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú
52-32-00
ALL ú ú 04 Page 549 ú Jun 18/99
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400 MAINTENANCE MANUAL
c) Do the initial latches open switch adjustment and replace the new value for the 8 |1/4 turns.
EXAMPLE: Assume 1 turn remains until stops are
_______ contacted. The 3 required turns minus the 1 actual turn equals 2 turns. Use 6 |1/4 turns (8 |1/4 minus 2).
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：747-400 AMM 飞机维护手册 舱门 DOORS 2(97)
