Mitsubishi Electric PUY-A12NKA7, Service Manual

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55
10-6-3. Check method of power circuit board
PUZ-A24NHA7 PUZ-A30NHA7 PUY-A24NHA7 PUY-A30NHA7
PUZ-A24NHA7-BS PUZ-A30NHA7-BS PUY-A24NHA7-BS PUY-A30NHA7-BS
Normal
Is the voltage of main incoming power
• Check the breaker and power supply.
Is the voltage to the compressor
(U-V,U-W and V-W) balanced?
Note: To check the voltage of the parts on this board with a tester is difficult due to its location.
Test points are limited.
• Check wiring.
• Check model setting switch SW6
on the outdoor controller circuit board.
• Replace the power board.
Is the voltage of CNDC(PNK) on outdoor
controller circuit board 280–380 V DC?
Yes
Yes
Yes
No
No
No
Power board check
198–253 V AC?
• Check wiring.
• Check power board.
Turn off the incoming power supply
and check the resistance of PTC1
and PTC2 on the noise filter circuit board.
PTC1 or PTC2 = open ?
Yes (open)
• Replace the power board.
No
(normal)
Power supply
52C relay
Bus bar voltage
(DC)
COMP (Hz)
OFF
ON
OFF
ON
0 Hz
ex. 48 Hz
0 V
290/325 V
370–390 V
208/230 V
min Hz
290/325 V
TIME CHART
power on starts stop
Power board
Controller
Board
CNDC
(PNK)
TB1
208/230V
±
10% AC
280V-380V DC
7 6 5 4 3 2 1
Comp
U
V
W
U-V 10V-270V AC
V-W 10V-270V AC
W-U10V-270V AC
Circuit diagram
1
3
208/230V
±10% AC
L1 L2
DCL
Outdoor Controller
OCH636A