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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
C
D
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)
Indoor 5
IF receive
input (SDI)
Micro
computer
5V
5V
5V
12V
5V
5V
Q201
5V
5V
5V
HIC
5V
R813
R812
C802
Q803
C804
R811
R810
SDO1
SDI1
16
77
0V
L801
L811
C801
R802 Q801
5V
R801
R803
D210
0V
0V
0V
0V
0V
0V
0V
C805
NF COIL
C802
C236
R253
R252
R251
R250
D215
C234
Q215
R244
R245
R248
R247
R246
R249
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 5
10
11
Summary of Contents for RAM-90QH5
Page 13: ... 12 ...
Page 14: ... 13 ...
Page 15: ... 14 ...
Page 19: ... 18 BASE DRAIN PIPE A DRAIN PIPE BUSH 100 mm ABOVE 10 11 ...
Page 21: ... 20 CONSTRUCTION AND DIMENSIONAL DIAGRAM MODEL RAM 90QH5 Service space ...
Page 26: ...CIRCUIT DIAGRAM MODEL RAM 90QH5 27 ...
Page 28: ... 31 ...
Page 31: ... 37 ...
Page 32: ... 39 ...
Page 33: ... 41 ...
Page 34: ... 43 ...
Page 36: ... 45 90 23 ...
Page 42: ... 51 REFRIGERATING CYCLE DIAGRAM MODEL RAM 90QH5 ...
Page 51: ... 60 3 System power Module Circuit ...
Page 60: ... 69 Electric expansion valve thermistor NARROW PIPE 5 5 5 5 8 8 8 ...
Page 72: ... 85 ...
Page 76: ... 90 Lighting mode self diagnosis lamp Location of self diagnosis lamp 1 RAM 90QH5 ...
Page 77: ... 91 Lighting mode self diagnosis lamp 2 RAM 90QH5 ...
Page 83: ...HITACHI PM NO 0371E Printed in Malaysia RAM 90QH5 ...