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1. Reset Circuit
●
The reset circuit is used to reset the program to its initial settings when the power is turned on or when the
power is recovered after a power failure.
●
The micro computer is reset when the reset input is “Hi”, and operation is possible when the reset input is
“Lo”.
●
The waveforms at each point when the power is turned on and off are shown in the diagrams.
●
When the power is turned on, the voltages of the DC 12V line and DC 5V lines are increased. When the
voltage of DC 12V lines reaches about 7V, ZD202 is turned ON, the potential of Q201’s base rises and Q202
is turned ON. Since Q202’s collector is set to “LO” at this time, Q202 is turned OFF and the reset input of
the micro computer is set to “Lo”. The DC 5V line voltage has already become 5V at this time and the micro
computer starts operation.
●
When the power is turned OFF, the voltage of the DC 12V line decreases. When it becomes about 7V, ZD202
is turned OFF, then Q201 is turned OFF, Q202 is turned ON the reset input of the micro computer is set to
“Hi’ and the micro computer is set to the reset mode.
POWER ON
12V
7V
5V
DC12V Line
DC5V Line
Base
POWER OFF
5V
Micro computer
Pin 7
12V
5V
0V
0V
Q201
C202
7
Micro computer
RES
Q202
ZD202
R205
R201
R204
R202
R203
+
C201
AX-7X30
DESCRIPTION OF MAIN CIRCUIT OPERATION
RAS-70YH7
Summary of Contents for RAC-70YH7
Page 35: ... 35 CIRCUIT DIAGRAM Remote Control ...
Page 36: ... 37 CIRCUIT DIAGRAM MODEL RAS 70YH7 ...
Page 37: ... 39 CIRCUIT DIAGRAM MODEL RAC 70YH7 ...
Page 39: ... 42 MODEL RAC 70YH7 P W B MAIN ...
Page 40: ... 43 P W B IPM BOARD P W B NF BOARD ...
Page 42: ... 45 51 53 53 55 57 49 29 66 23 25 25 25 25 ...
Page 46: ... 53 ...
Page 56: ... 66 220 240 220 240 3 15A RAC 70YH7 ...
Page 57: ... 67 AC220 240V DC260 360V ...
Page 58: ... 68 C001 C007 C015 C016 C026 C027 L004 L005 J25 J25 J25 J23 J58 J25 ...
Page 60: ... 70 ...
Page 61: ... 71 ...
Page 62: ... 72 3 15A Fuse ...
Page 63: ... 73 3 15A 3 15A DC260 360V ...
Page 66: ... 76 ...
Page 67: ... 77 ...
Page 68: ... 78 TROUBLE SHOOTING ...
Page 69: ... 79 DISCHARGE PROCEDURE AND METHOD TO STOP ENERGIZE THE POWER CIRCUIT ...
Page 70: ... 80 ...
Page 75: ... 85 2 Outdoor unit does not operate but receives remote infrared signal ...
Page 80: ... 90 AC220 240V AC240V P W Bs P W Bs Replace outdoor P W B Main P W Bs ...
Page 81: ... 91 Replace outdoor P W B Main Replace fan motor Replace outdoor P W B Main ...
Page 83: ... 93 ...
Page 84: ... 94 ...
Page 86: ... 96 CHECKING THE REMOTE CONTROLLER ...
Page 92: ...PM NO 0465E Printed in Malaysia RAS 70YH7 RAC 70YH7 ...