Mitsubishi Electric MXZ-2C20NAHZ, Service Manual

Page: 83 / 96

83
11-7. TEST POINT DIAGRAM AND VOLTAGE
1. Outdoor control P.C. board
MXZ-3C24NA MXZ-3C30NA
MXZ-4C36NA
0 10 20 30 40 50 60 70 80 90 100 110 120
32 50 68 86 104 122 140 158 176 194 212 230 248
700
600
500
400
300
200
100
0
(ºC)
(ºF)
Thermistor R100 = 13.36 k Ÿ ± 2% , B constant = 4014 ± 2%
Rt = 13.36exp{4014( )} , t: ºC = (ºF - 32)/1.8
5HVLVWDQFHNŸ
Temperature
273+t
1
373
1
Discharge temperature thermistor (RT62)
-20 -10 0 10 20 30 40
-4 14 32 50 68 86 104
(ºC)
(ºF)
100
90
80
70
60
50
40
30
20
10
0
5HVLVWDQFHNŸ
Temperature
273+t
1
298
1
Thermistor R25 = 10 k Ÿ ± 2%
B constant = 3950 ± 2%
Rt = 10exp{3950( )}
t : ºC = (ºF - 32)/1.8
Defrost thermistor (RT61)
Ambient temperature thermistor (RT65)
Outdoor heat exchanger temperature
thermistor (RT68)
CN601
230 V AC Room A
Input
Room B Room C Room D
Defrost thermistor
(RT61)
Discharge temperature
thermistor (RT62)
Outdoor heat exchanger
temperature thermistor
(RT68)
CNTH1
CNTH2
Ambient temperature
thermistor
(RT65)
SW1
LED3
LEV: 12 V DC
pulse wave
LED2
LED1
SW2
SW871
CN712 R.V. coil
208/230 V AC
Output
CN713 Valve coil
208/230 V AC
Output
CN714 Base heater
208/230 V AC
Output
CNAC
to outdoor power P.C.
board 208/230 V AC
Input
F711 FUSE
T3.15AL250V
CN611
Serial signal 12 ~ 24 V
CN621
(
(-)
CN701 Signal transmission (T
o power board)
5 V DC pulse wave CN702 Signal transmission (T
o power board)
5 V DC pulse wave
(+)
(+)
(-) (-)
15 V
(-)
15 V
CN63H
High
pressure
switch
CNDC
Bus-bar
voltage
290 ~ 370
VDC
Bus-bar voltage
290 ~ 370 V DC
15 V DC
CNF1
To fan motor
V
FG
(Rotate signal)
(Voltage between
right pins of PC931,
pin 3 and pin 4)
(Same as
&1)í
V
SP
(Rotate instruction)
(Voltage between pins
of C930): 0 V DC
(when stopped),
1.8 - 6.5 V DC
(when operated)
(Correspond to
&1)í
CN741
Signal translation
(To Communication
adaptor board)
CN791 LEV Room
A
CN792 LEV Room B CN794 LEV Room D CN793 LEV Room C
OBH702E