Heat Source Unit Circuit Board - Mitsubishi Electric PQHY-P72TYHMU-A Service Handbook

[ III Heat source Unit Components ]

[3] Heat source Unit Circuit Board

1. Heat source unit control board
CNDC
Bus voltage input
P
N
CNAC2
L1
L2
CN505
72C driving output
(THMU)
CN51
Output 12VDC
Compressor
ON/OFF output
Error output
Actuator
driving output
CN72
72C driving output
(YHMU)
LED3
Lit when powered
LED2
Lit during normal
CPU operation
CNAC
L1
L2
HWE09080
CN2
Serial communication signal input
CN801
GND INV board
Pressure switch
Output 17VDC
connection
F01
External signal input (contact input)
Fuse
250V AC/3.15A
CN102
Power supply input for centralized control system (30VDC)
Indoor-heat source transmission line input/output (30VDC)
- 81 -
CN332
CN4
Output 18VDC
GND
GND
Serial communication signal output
CN41
CNIT
Power supply for
Output 12VDC
CN40 centralized control OFF
GND
Power supply for
centralized control ON
Output 5VDC
Power supply detection input
Power supply ON/OFF signal output
CNS2
Transmission line input/output
for centralized control system (30VDC)
LEV
driving output
LED1
Service LED
SWU1,2
Address switch
SW1-5
Dip switch
Sensor
input
CNVCC2
Output 12VDC
Output 5VDC
GND
GB