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10. Outdoor DC Fan Motor control circuit
U
V
W
This model uses DC Fan Motor which is including controller circuit into the Motor shell.
This DC Fan Motor will rotate by control voltage apply to Vsp input. (Voltage range: 1.7 to 7V DC)
Vsp high : Faster ; Vsp low : slower ; Vsp lower than 1.7V : stop
Motor will output FG pulse by following this motor revolution.
Outdoor Microcomputer will output PWM control signal from pin (FMCHOP) terminal by following the instruction from
indoor Microcomputer.
This PWM control signal will convert to Vsp voltage by smoothing circuit (Q101 & RC filter)
Fan motor will start to rotate when Vsp was proceeding over than 1.7V, and generate FG pulse by rotation speed.
FG pulse will feed back to Outdoor Microcomputer through PQ102.
PQ102 is the isolator between Microcomputer circuit and DC Fan Motor circuit, which has to match the Fan Motor revolution
with instructed revolution. Such as...
FG feedback : Faster - Instruction : Slower ... Decrease pulse width
FG feedback : Slower - Instruction : Faster ... Increase pulse width
FG pulse is also used for Fan Motor fail detection.
Microcomputer will monitor FG pulse 30 seconds after start the fan motor. If there is no signal detected, it will consider that
the Fan Motor was malfunction and stop the operation. In this case, LD302 on main P.W.B. will blink 12 times. (Fan Motor
lock detected)
R107 and IC4 are used for Fan Motor over current.
Power board in system power module
DC Fan motor with control board
HIC
Power supply for DC fan motor from smoothing
capacitor in system power module
Smoothing Capacitor
+ +
+
1
1
1
1
2
2
2
2
3
3
3
Main P.W.B.
2A-Fuse
C102
0V
Vcc
FG Pulse
BOARD
VSP
Motor coil
RC Filter
ONE CHIP DRIVER IC
PWM control voltage
Q101
R107
R101
D101
R108
R242
R298
R246
Q201
R297
R244
R283
R102
FM-15V
FM-0V
FM-0V
FM-15V
PQ102
1
2
3
4
5V
5V
5V
Ap 7V
33.3KHz
t
T
T/2
0V
0V
12V
C208
IC4
0V
0V
0V
0V
0V
R115
R104
R105
R103
R106
R114
C103
C106
C104
C209
D105
R243
C219
ZD101
+
3
4
4
5
5
6
7
+
+
-
8
2
3
1
65
61
60
59
75
15
FAN
LIMITTER
FMCHOP
FM-60 el
FG PULSE
input