TASK 21-51-08-702-016
 4. Pack Discharge Overheat Switch Test (Fig. 201)
___________________________________
 A. General
 (1)  This task does a test of the electrical circuit for the pack discharge overheat switch. This task does not make sure that the pack overheat switch is calibrated correctly. A calibration test of the overheat switch must be done off of the airplane.
 B. References
 (1)  
AMM 06-09-03/201, Body Section 44 Access Doors and Panels

 (2)  
AMM 24-22-00/201, Manual Control

 (3)  
WDM 21-51-21, WDM 21-51-22, WDM 21-51-23

 (4)  
SSM 21-51-02

 C. Access
 (1)  
Location Zones
 133 Air Conditioning Equipment Bay, LH
 134 Air Conditioning Equipment Bay, RH

 (2)  
Access Panels
 192H-R Air Conditioning Access Door
 191N-L Air Conditioning Access Door

 D. Prepare for the Test
 S 862-037
 (1)  Open these circuit breakers, on the P6 Main Power Distribution Panel, and attach a DO-NOT-CLOSE tag:
 (a)  
6F35, PACK TEMP CONT A

 (b)  
6F36, PACK TEMP CONT B

 S 862-017
 (2)  
Supply electrical power (AMM 24-22-00/201).

 S 862-018

 (3)  
Make sure the applicable (1, 2, or 3) PACKS selector, on the overhead panel, P5, is in the NORM position.

 (4)  
Make sure the EICAS message system operates normally.

 (5)  
Push the ECS switch on the EICAS display select panel.

 S 012-021

 (6)  
Open the applicable access door (AMM 06-09-03/201):

 S 862-019
 S 862-020
 -191N-L for packs 1 or 2
 -192H-R for pack 3
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BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400 MAINTENANCE MANUAL
 E. Do the Test
 S 022-022
 (1)  Disconnect the applicable electrical connector from the pack discharge overheat switch:
 -DS519 for pack 1
 -DS518 for pack 2
 -DS521 for pack 3
 S 422-023
 (2)  
Install a jumper wire between pin 1 and pin 2 of the electrical connector.

 S 212-024

 (3)  
Make sure the SYS FAULT light on the applicable PACK RST switch on the P5 panel comes on.

 S 022-025

 (4)  
Remove the jumper wire from the electrical connector.

 S 422-026

 (5)  
Reconnect the applicable electrical connector to the pack discharge overheat switch:

 -DS519 for pack 1
 -DS518 for pack 2
 -DS521 for pack 3
 S 212-027
 (6)  Make sure that the SYS FAULT light goes off when you push the PACK RST switch.
 F. Put the Airplane Back to its Usual Condition
 S 412-028
 (1)  Close the applicable access door (AMM 06-09-03/201):
 -191N-L for packs 1 or 2
 -192H-R for pack 3
 S 862-029
 (2)  Make sure the applicable (1, 2, or 3) PACKS selector, on the overhead panel, P5, is in the OFF position.
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 ALL  ú ú 03 Page 206 ú Oct 18/01
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400
MAINTENANCE MANUAL

 (3)  S 862-038Remove the DO-NOT-CLOSE tag and close these circuit breakers, on the P6 Main Power Distribution Panel: (a) 6F35, PACK TEMP CONT A (b) 6F36, PACK TEMP CONT B
 (4)  S 862-030Remove the electrical power if it is not needed (AMM 24-22-00/201).

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本文鏈接地址：747-400 AMM 飛機維護手冊 空調 AIR CONDITIONING 2(34)