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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)
IF receive
input (SDI)
Micro
computer
5V
5V
5V
12V
5V
5V
IC8
R283
Q201
5V
5V
5V
HIC
5V
R813
R812
C802
Q803
C804
R811
R810
SDO1
SDI1
73
68
0V
L801
L811
C801
R802 Q801
5V
R801
R803
D209
0V
0V
0V
0V
0V
0V
0V
C805
NF COIL
C802
C216
R263
R262
R261
R260
D206
C214
Q206
R254
R255
R258
R257
R256
R259
C806
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
10
11
15
2
Summary of Contents for RAM-55QH5
Page 31: ... 30 CAPACITY DIAGRAM RELATED TO THE PIPING LENGTH MODEL RAM 65QH5 ...
Page 37: ...CIRCUIT DIAGRAM MODEL RAM 55QH5 39 L C023 C022 C002 C001 C025 C024 N ...
Page 38: ...CIRCUIT DIAGRAM MODEL RAM 65QH5 41 L C023 C022 C002 C001 C025 C024 N ...
Page 41: ... 45 ...
Page 46: ... 51 Outdoortemperature STAROTP_C TSKTM1_C1 Outdoortemperature STAROTP_C TSKTM1_C2 ...
Page 47: ... 53 ...
Page 48: ... 55 ...
Page 49: ... 57 ...
Page 50: ... 59 ...
Page 68: ... 77 5A ...
Page 75: ... 84 ...
Page 76: ... 85 5 Reversing valve control circuit Fig 5 1 ...
Page 91: ... 103 ...
Page 92: ... 104 ...
Page 98: ... 110 TROUBLESHOOTING OF THE SYSTEM POWER MODULE ...
Page 99: ... 111 ...
Page 100: ... 112 ...
Page 102: ... 114 three three inlet 3 Cut off the three pipes at the side and bottom of Reversing valve ...
Page 103: ... 115 ELECTRIC EXPANSION VALVE PIPE THERMISTOR POSITION CHARTS MODEL RAM 55QH5 MODEL RAM 65QH5 ...
Page 108: ...HITACHI PM NO 0312E Printed in Malaysia RAM 55QH5 RAM 65QH5 ...