FILE NO. SVM-02007
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(1) Role of indoor unit controller
The indoor unit controller judges the operation
commands from the remote controller and
assumes the following functions.
•
Judgement of suction air temperature of the
indoor heat exchanger by using the indoor temp.
sensor (TA sensor).
•
Temperature setting of the indoor heat
exchanger by using heat exchanger sensor
(TC sensor).
•
Louver motor control
•
Indoor fan motor operation control
•
LED 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 judgement/display of error
(2) Role of outdoor unit controller
Receiving the operation command signal (Serial
signal) from the indoor controller, the outdoor unit
performs its role.
•
Compressor operation
control
•
Operation control of
outdoor fan motor
•
4 way valves
•
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 to indoor unit
•
Detection of outdoor temperature and operation
revolution control
•
Defrost control in heating operation (Temperature
measurement by outdoor heat exchanger and
control for 4 way valves and outdoor fan).
8. OPERATION DESCRIPTION
8-1. Outlined of Air Conditioner Control
This air conditioner is a capacity-variable type air
conditioner, which uses DC motor for the indoor fan
motor and AC motor for the outdoor fan motor. And the
capacity proportional control compressor which can
change the motor speed in the range from 18 to 120
rps is mounted. The DC motor drive circuit is mounted
to the indoor unit. The inverter to control compressor
are mounted to the outdoor unit. The entire air condi-
tioner 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 4 way valves. 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.
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 judgement of serial
signal from indoor
side.
