AIR CYCLE
MACHINE
RAM AIR INLET FAN
ACTUATOR
RAM AIR EXIT
ACTUATOR
RAM AIR
INLET DOOR COOLING AIR
SEE A CHECK VALVE
RAM AIR
EXIT DOOR
SEE B
RAM AIR INLET
ACTUATOR
RAM AIR
DOOR DUCT
PANEL
AIRFLOW
DOOR OPEN
DOOR CLOSED A
RAM AIR OUTLET ACTUATOR
DOOR OPEN
B
Ram Air Flow Diagram
Figure 3
EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú
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B. CLX 001-004, 101 POST-SB 21-2388;
CLX 005-099;
On the ground after the the pack temperature controller commands the
actuator to drive the door to the full open position, the exit door
actuators will remain unpowered.
C. A position switch mounted on the exit door is used in conjunction with a switch in the turbine bypass valve to shut down the pack in case of improper sequencing of the actuator and the bypass valve.
6. Pack Discharge Temperature Sensor (Fig. 2)
_________________________________
A. A pack discharge temperature sensor is mounted in each of the pack discharge ducts downstream of the water separator to provide temperature information to the pack temperature controllers.
7. Operation (Fig. 4 and Fig. 5)
_________
A. Functional Description
(1)
On the ground the primary pack temperature controller opens the ram air inlet and exit doors. The ACM fan forces cooling air through the heat exchanger. The turbine bypass valve is positioned to provide the pack discharge temperature demanded by the zone temperature controller.
(2)
CLX 001-004, 101 POST-SB 21-2388; CLX 005-099; On the ground, after the primary pack temperature controller opens the ram air inlet and exit doors, the ram air inlet and exit doors will remain unpowered
123
PACK OUTLET TEMP 20 20 20
PACK FLOW 250 250 250
TBV POSITION 0.65 0.65 0.65
RAI POSITION 0.35 0.35 0.35
RAE POSITION 0.35 0.35 0.35
COMP OUTLET TEMP 200 200 200
WATER SEP DELTA P 2 2 2
PRI HX INLET TEMP 190 190 190
PRI HX OUTLET TEMP 85 85 85
SEC HX OUTLET TEMP 60 60 60
PTC CHANNEL IN CONT A A A
AIR CONDITIONING SYSTEM MAINTENANCE PAGE
AUXILIARY EICAS DISPLAY
Air Conditioning Pack Temperature Control EICAS Displays
Figure 4
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TO INPUTS TO PTC A
E2-6 ELECTRONICS SHELF
Air Conditioning Pack Temperature Control Schematic Figure 5 (Sheet 1)
EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. AIRPLANES PRE-SB 21-2388 ú
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(WITHOUT PACK SEVER RELAY) ú ú 01 Page 7 ú Oct 18/00
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Air Conditioning Pack Temperature Control Schematic Figure 5 (Sheet 2)
L53068
EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. AIRPLANES POST-SB 21-2388 ú
21-62-00 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 空调 AIR CONDITIONING 2(164)
