Mitsubishi Electric SUZ-KA24NAHZ Service Manual page 59

Outdoor power circuit board
SUZ-KA30NAHZ
SUZ-KA36NAHZ
CN4
Connect to the outdoor
CN6
controller circuit board
Thermistor
(CN4)
CN2
Connect to the outdoor controller circuit board (CN2)
1–5: Transmitting signal to outdoor controller
circuit board (0–5 VDC)
2–5: Zero cross signal
(0–5 VDC)
3,4: 15 VDC
6–5: 15 VDC
7–5: 15 VDC
OCH754A
Brief Check of POWER MODULE
If they are short-circuited, it means that they are broken.
Measure the resistance in the following points (connectors, etc.).
1. Check POWER MODULE
1 Check of DIODE circuit
R – P1 S – P1
2 Check of PFC circuit
P2 – L1 P2 – L2 P2 – L3 N2 – L1 N2 – L2 N2 – L3
3 Check of INVERTER circuit
P3 – U , P3 – V , P3 – W , N3 – U , N3 – V , N3 – W
Note: The marks R , S , L1 , L2 , L3 , P1 , P2 , P3 , N1 , N2 , N3 ,
U , V and W
CNAC1, CNAC2
208/230 VAC
Connected to the outdoor
controller circuit board
(CNAC)
TB-U, TB-V, TB-W
Connect to the compressor (MC)
P3
U
V
W
N3
P2
L1
L2
L3
N2
S
R
N1
P1
TB1A, TB2A, TB3A, TB1B,
TB2B, TB3B
Connected to DCL
59
R – N1 S – N1
show in the diagram are not actually printed on the board.
NI, LI
Voltage of 208/230 VAC is input
(Connected to the terminal block
(TB1))
CNDC
280–380 VDC (1+, 3–)
connect to the outdoor
controller circuit board
(CNDC)
EI,E2,E3,E4
Connected to
the ground