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10. Outdoor DC Fan Motor control circuit
This model uses DC Fan Motor which has a controller circuit built in the Motor.
This DC Fan Motor will rotate by control voltage apply to Vsp input. (Voltage range: 1.7 to 7V DC)
Motor will output FG pulse by following this motor revolution.
indoor microcomputer.
This PWM control signal will convert to Vsp voltage by smoothing circuit (R242 & C209)
rotation speed.
DC Fan Motor circuit 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 failure 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 control
R107 and IC4 are used for Fan Motor over current.
Vsp high : Faster ;
Vsp low : slower ;
Vsp lower than 1.7V : stop
P.W.B. will blink 12 times. (Fan Motor lock detected)
FG pulse will feed back to Outdoor microcomputer 15 .
Outdoor microcomputer will output PWM control signal from 75 by following the instruction from
Fan motor will start to rotate when Vsp was proceeding over than 1.7V, and generate FG pulse by
Summary of Contents for RAC-18YH4
Page 21: ... 19 GRAM 18YH4 RAC 18YH4 CAUTION The marked parts are very important ones for safety ...
Page 23: ... 21 RAS 18YH4 MODEL ...
Page 24: ... 23 RAC 18YH4 MODEL Ｈ８ ３ ０ ３ ９ ＡＸ ８ Ｔ １ ０ ...
Page 27: ... 26 MAIN P W B MARKING ON P W B COMPONENT SIDE SOLDERING SIDE MODEL RAC 18YH4 ...
Page 29: ... 29 button MODEL RAS 18YH4 BASIC MODE 31 33 33 33 37 35 ...
Page 35: ... 38 REFRIGERATING CYCLE DIAGRAM MODEL RAS 18YH4 RAC 18YH4 SUCTION TANK SUCTION TANK ...
Page 99: ...Printed in Japan TSK AW NO 0004E RAS 18YH4 RAC 18YH4 ...
