Mitsubishi Electric MXZ-8A140VA Technical & Service Manual page 65

9-7-3. Outdoor power circuit board
MXZ-8A140VA
CN5
Detection of
primary current
CN3
(Connect to the
Temperature
outdoor noise filter <Heatsink>
(TH8)
circuit board (CN5))
SC-P1
Connect to 52C
Brief Check of POWER MODULE
W Usually, they are in a state of being short-circuited if they are broken.
Measure the resistance in the following points (connectors, etc.).
If they are short-circuited, it means that they are broken.
1. Check of POWER MODULE
1.Check of DIODE circuit
L - P1 , N - P1 , L - N1 , N - N1
2.Check of IGBT circuit
P2 - U , P2 - V , P2 - W , N2 - U , N2 - V , N2 - W
Note:The marks, L , N , N1 , N2 , P1 , P2 , U , V and W
shown in the diagram are not actually printed on the board.
CN4
Connect to the
CNAF
outdoor controller
Connect to
circuit board
ACTM
(CN4)
N1
P2
P1
SC-N1
POWER
Connect to ACTM
MODULE
65
CN2
Connect to the outdoor controller circuit
board (CN2)
1-5: Power circuit board
signal to the controller board (0-5V DC)
2-5: Zero cross signal (0-5V DC)
3-4: 18V DC
[ 5 : –
6-5: 15V DC
[ 4 : –
7-5: 15V DC
W
V
U
N2
N
L
CNDC
–
}
280V-350V DC
+
Connect to the outdoor controller
circuit board (CNDC)
Transmitting
1, 2, 6, 7 : + ]
3 : + ]
TAB-U, TAB-V,
TAB-W
Connect to the
compressor (MC)
Voltage among
phases:
5V-180V AC
SC-R, SC-S
Connect to the
outdoor noise filter
circuit board
(LO, NO)
220V-240V AC
SC-P2, SC-N2
Connect to
ACTM and the
soothing
capacitor