– 20 –
9-1. Outline of Air Conditioner Control
This air conditioner is a capacity-variable type air
conditioner, which uses DC motor for the indoor fan
motor and the outdoor fan motor. And the
capacityproportional control compressor mounted. The
DC motor drive circuit is mounted to the indoor unit.
The compressor and the inverter to control fan motor
are mounted to the outdoor unit.
The entire air conditioner is mainly controlled by the
indoor unit controller.
The indoor unit controller drives the indoor fan motor
based upon command sent from the remote controller,
and transfers the operation command to the outdoor
unit controller.
The outdoor unit controller receives operation
command from the indoor unit side, and controls the
outdoor fan and the pulse motor valve. (P.M.V)
Besides, detecting revolution position of the
compressor motor, the outdoor unit controller controls
speed of the compressor motor by controlling output
voltage of the inverter and switching timing of the
supply power (current transfer timing) so that motors
drive according to the operation command.
And then, the outdoor unit controller transfers reversely
the operating status information of the outdoor unit to
control the indoor unit controller.
1.Role of indoor unit controller
The indoor unit controller judges the operation
commands from the remote controller and assumes
the following functions.
• Judgment of suction air temperature of the indoor
heat exchanger by using the indoor temp. sensor.
(TA sensor)
• Judgment of the indoor heat exchanger
temperature by using heat exchanger sensor (TC
sensor) (Prevent-freezing control, etc.)
• Indoor fan motor operation control
• LED (Light Emitting Diode) display control
• Transferring of operation command signal (Serial
signal) to the outdoor unit
• Reception of information of operation status (Serial
signal including outside temp. data) to the outdoor
unit and judgment/display of error
2.Role of outdoor unit controller
Receiving the operation command signal (Serial
signal) from the indoor unit controller, the outdoor
unit performs its role.
• Detection of inverter input current and current
release operation
• Over-current detection and prevention operation to
IGBT module (Compressor stop function)
• Compressor and outdoor fan stop function when
serial signal is off (when the serial signal does not
reach the board assembly of outdoor control by
trouble of the signal system)
• Transferring of operation information (Serial signal)
from outdoor unit controller to indoor unit controller
• Detection of outdoor temperature and operation
revolution control
• Defrost control in heating operation (Temp.
measurement by outdoor heat exchanger and
control for 4-way valve and outdoor fan)
3.Contents of operation command signal (Serial
signal) from indoor unit controller to outdoor
unit controller
The following three types of signals are sent from the
indoor unit controller.
• Operation mode set on the remote controller
• Compressor revolution command signal defined by
indoor temperature and set temperature
(Correction along with variation of room
temperature and correction of indoor heat
exchanger temperature are added.)
• Temperature of indoor heat exchanger
• For these signals ([Operation mode] and
[Compressor revolution] indoor heat exchanger
temperature), the outdoor unit controller monitors
the input current to the inverter, and performs the
followed operation within the range that current
does not exceed the allowable value.
4.Contents of operation command signal (Serial
signal) from outdoor unit controller to indoor
unit controller
The following signals are sent from the outdoor unit
controller.
• The current operation mode
• The current compressor revolution
• Outdoor temperature
• Existence of protective circuit operation For
transferring of these signals, the indoor unit
controller monitors the contents of signals, and
judges existence of trouble occurrence.
Contents of judgment are described below.
• Whether distinction of the current operation
status meets to the operation command signal
• Whether protective circuit operates When no
signal is received from the outdoor unit
controller, it is assumed as a trouble.
• Compressor operation control
• Operation control of outdoor fan motor
• P.M.V. control
• 4-way valve control
As the compressor adopts four-pole brushless DC
motor, the frequency of the supply power from
inverter to compressor is two-times cycles of the
actual number of revolution.
Operations followed to judgment
of serial signal from indoor side.
Summary of Contents for ras-m07g3dv-e
Page 86: ... 85 13 EXPLODED VIEWS AND PARTS LIST 13 1 Indoor Unit ...
Page 93: ......