13
High
Rotational frequency
High
time
Med.
Low
8-5. INDOOR FAN MOTOR CONTROL
(1) Rotational frequency feedback control
The indoor fan motor is equipped with a rotational frequency sensor, and outputs signal to the microprocessor to
feedback the rotational frequency. Comparing the current rotational frequency with the target rotational frequency
(High, Med., Low), the microprocessor controls SR141 and adjusts fan motor electric current to make the current rota-
tional frequency close to the target rotational frequency. With this control, when the fan speed is switched, the rotational
frequency changes smoothly.
(2) Fan motor lock-up protection
When the rotational frequency feedback signal has not output for 12 seconds, (or when the microprocessor cannot
detect the signal for 12 seconds) the fan motor is regarded locked-up. Then the electric current to the fan motor is shut
off. 3 minutes later, the electric current is applied to the fan motor again. During the fan motor lock-up, the OPERATION
INDICATOR Indicator lamp flashes on and off to show the fan motor abnormality. (Refer to page 21.)
AUTO
Horizontal
1
2
3
4
5
Middle
Downward
Swing
8-6. AUTO VANE OPERATION
1. Horizontal vane
(1) Vane motor drive
These models are equipped with a stepping motor for the horizontal vane. The rotating direction, speed, and angle of
the motor are controlled by pulse signals (approx. 12V) transmitted from indoor microprocessor.
(2) The horizontal vane angle and mode changes as follows by pressing the VANE button.
①
In COOL and DRY operation
➁
In FAN operation
Vane angle is fixed to Angle 1.
Vane angle is fixed to Angle 4.
(3) Positioning
The vane is once pressed to the vane stopper below to confirm the standard position and then set to the desired angle.
Confirming of standard position is performed in case of follows.
(a) When the OPERATE/STOP (ON/OFF) button is pressed. (POWER ON/OFF)
(b) When the vane control is changed from AUTO to MANUAL.
(c) When the SWING is finished.
(d) When the test run starts.
(e) When the power supply turns ON.
(4) VANE AUTO (
) mode
In VANE AUTO mode, the microprocessor automatically determines the horizontal vane angle and operation to make the
optimum room-temperature distribution.
(5) STOP (operation OFF) and ON-TIMER standby.
When the following cases occur, the horizontal vane returns to the closed position.
(a) When the OPERATE/STOP (ON/OFF) button is pressed (POWER OFF).
(b) When the operation is stopped by the emergency operation.
(c) When the ON-TIMER is on standby.
(6) Dew prevention
During COOL or DRY operation at Vane Angle 4 or 5 when the compressor cumulative operation time of compressor
exceeds 1 hour, the vane angle automatically changes to Angle 1 for dew prevention.
(7) SWING MODE (
)
By selecting SWING mode with the VANE button, the horizontal vane swings vertically. The remote controller displays
“
”.
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