Mitsubishi Heavy Industries SCM71ZM-S1 Technical Manual page 223

(12) Outdoor unit inspection points
Models SCM71ZM-S1,80ZM-S1
CAUTION- HIGH VOLTAGE
High voltage is produced in the control box. Don't touch
electrical parts in the control box for 5 minutes after the
Power source unit is stopped.
1 Phase
AC220-240V 50Hz
220V 60Hz FUSE
TB1
250V 20A
BK BK
L
WH WH
N
Y／G
Y／G
TB2
BK
1
WH
2
UNIT A
RD
3
Y／G
TB3
BK
1
WH
2
UNIT B
BR
3
Y／G
TB4
BK
1
WH
2
UNIT C
BL
3
Y／G
TB5
BK
1
WH
2
UNIT D
YE
3
Y／G
Y／G
◆Voltage check in PCB
The normal range is as follows.
Display Voltage range
①DC280V DC230V - DC310V
②DC220V DC218V - DC222V
③DC213V DC212V - DC214V
④DC215V DC214V - DC216V
⑤DC225V DC224V - DC226V
⑥DC 2.5V DC 2.3V - DC22.5V
PCB 1（MAIN）
◆Inspection power transistor
Remove the fasten terminal and test
output voltage
R
IN
S
IN
G1
CNA
CNB
PCB 2（SUB）
CNC
CND
G2 CNEEV1
Y／G
WH
M
EEV A
◆Inspection of electronic
M
CM
expansion valve
3～
See page 223.
V W
⑥
L
◆Power source and serial signal inspection
① to ②: AC 220/230/240V
② to ③ : Normal if the voltage oscillates between
DC 0 and approx. 20V
CNEEV2
RD BL GN
M M M
EEV B EEV C EEV D
①
②
CNSUB
⑤
CNTH
CNFAN
④
CNTH
2 2 2 2
L
FMo
TH1 TH2 TH3 TH4
◆Inspection of resistance value of sensor
Remove the connector and check the resistance value.
See the section of sensor characteristics on page 214.
222
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'17 • SCM-T-225
Color marks
Mark
BK
BL
BR
RD
WH
OR
BR
YE
Y／G
BK
R
O
WH
S
O
WH
S-1
RD
C-1
5
CNMAIN
2
CN20V
C-2
S-2
③
S R
CNFAN CN20S CNHEAT
RD WH
M
20S HEATER
◆Inspection of outdoor fan motor
See page 223.
Color
Black
Blue
Brown
Red
White
Orange
Brown
Yellow
Yellow／Green