Hitachi RAC-60DH7 - Page 54

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● Fig. 2-1 shows the interface circuit used for the indoor and outdoor microcomputers to communicate with
each other.
Indoor P.W.B.
Outdoor P.W.B.
Terminal board
Terminal board
C
D
CD
D101
I/F 0V
C821 R821
C822
0V
0V
0V
0V
5V 5V 5V
0V
0V
0V
5V
0V
0V
0V
0V
0V
I/F 0V
0V
IF transmit
output (SDO)
IF receive
input (SDI)
Micro
computer
5V
5V
5V
12V
5V 5V
IC8
R283
Q201
5V
5V5V
HIC
5V
R813
R812
C802
Q803
C804
R811
R810
SDO1
SDI1
73
68
0V
L801
L811
C801
R802
Q801
5V
R801
R803
D210
0V
0V
0V
0V
0V
0V0V
C805
NF COIL2
C802
C216
R263
R262
R261
R260
D206
C214
Q206
R254
R255
R258
R257
R256
R259
C803
C804
Interface
relay
35V
(Communications from indoor micro computer to outdoor micro computer)
(Communications from outdoor micro computer to indoor micro computer)
Fig. 2-1 Indoor / Outdoor interface Circuit
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11
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