(d)
While pressing PACK TRIP OFF light, move LIGHTS switch to DIM and check that light dims.
(e)
Continue to press PACK TRIP OFF light, move LIGHTS switch to BRT and check that light brightens.
(5)
Check that air conditioning PACK switch is in OFF position.
(6)
Open air conditioning equipment bay door.
(7)
Simulate open position of pack valve.
(a)
Open OVERHEAT circuit breaker.
(b)
Remove connector from pack valve limit switch. (See figure 501.)
(c)
Close OVERHEAT circuit breaker.
D. Test Pack Protective Circuit
(1)
Move air conditioning PACK switch to ON and check for a click at solenoid A of the pack valve.
(2)
Move temperature selector knob toward MANUAL WARM to drive mix valve away from the full cold position.
(3)
Check compressor discharge overheat circuit.
(a)
Disconnect electrical connector from compressor discharge overheat switch in air cycle machine compressor scroll.
(b)
Install a jumper wire between two pins of electrical connector.
1) Check that both MASTER CAUTION lights, the AIR COND annunciator light, and the PACK TRIP OFF light come on and that after lights come on a click is felt at solenoid A of the pack valve.
2) After click is felt, open OVERHEAT circuit breaker, reconnect electrical connector removed in step 3.C.(7)(b), close OVERHEAT circuit breaker and check that mix valve drives to full cold position by observing AIR MIX VALVE position indicator.
500
21-51-0 Page 506 B
O
E
I
NG
P
R
OP
R
I
E
T
A
R
Y
- Copyri
ght
. - Unpubl
i
s
hed
W
o
r
k
-
S
ee
t
i
t
l
e page f
o
r de
t
a
i
l
s
.
May 01/01
(c)
Depress either MASTER CAUTION light. Check that AIR COND annunciator light and both MASTER CAUTION lights go off, but PACK TRIP OFF light remains on.
(d)
Depress any system MASTER CAUTION annunciator light. Check that both MASTER CAUTION lights and all master caution annunicator lights come on but, when released, only both MASTER CAUTION lights, AIR COND annunciator light, and PACK TRIP OFF light remain on.
(e)
Remove jumper wire.
(f)
Open OVERHEAT circuit breaker, remove pack valve limit switch connector from pack valve, then close OVERHEAT circuit breaker.
(g)
Push TRIP RESET switch and check that PACK TRIP OFF light, AIR COND annunciator light and both MASTER CAUTION lights go off, and check for click at solenoid A of the pack valve.
(h)
Connect electrical connector to compressor discharge overheat switch in air cycle machine compressor scroll.
(4) Check turbine inlet overheat switch circuit.
(a)
Move temperature selector knob to MANUAL WARM to drive valve away from full cold position.
(b)
Disconnect electrical connector from turbine inlet overheat switch in air cycle machine turbine inlet duct.
(c)
Install jumper wire between two pins of electrical connector.
1) Check that both MASTER CAUTION lights, AIR COND annunciator light, and PACK TRIP OFF light come on. When lights come on, check for click at solenoid A of pack valve.
2) After click is felt, open OVERHEAT circuit breaker, reconnect pack valve limit switch electrical connector removed in step 3.D.(3)(f), close OVERHEAT circuit breaker and check that mix valve drives to full cold position by observing AIR MIX VALVE position indicator.
(d)
Remove jumper wire.
(e)
Open OVERHEAT circuit breaker, remove pack valve limit switch electrical connector from pack valve, then close OVERHEAT circuit breaker.
(f)
Push TRIP RESET switch and check that PACK TRIP OFF light, AIR COND annunciator light and both MASTER CAUTION lights go off and check for click at solenoid A of pack valve.
(g)
Connect electrical connector to turbine inlet overheat switch in air cycle machine turbine inlet duct.
(h)
Open OVERHEAT circuit breaker, install pack valve limit switch electrical connector, then close OVERHEAT circuit breaker.
(5)
Move air conditioning PACK switch to OFF.
(6)
Close applicable air conditioning equipment bay door.
(7)
If no longer required, remove electrical power from airplane.
May 01/01 21-51-0 Page 507
中國航空網 m.k6050.com
航空翻譯 www.aviation.cn
本文鏈接地址：737 AMM 飛機維護手冊 AIR CONDITIONING 空調(73)
