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29
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Item
4. Capacity
control
Operation flow and applicable data, etc.
The cooling or heating capacity depending on the load is
adjusted.
According to difference between the setup value of tempera-
ture and the room temperature, the capacity is adjusted by
the compressor revolution.
Description
1) The difference between set
temperature on remote controller
(Ts) and room temperature (Ta)
is calculated.
2) According to the temperature
difference, the correction value of
Hz signal which determines the
compressor speed is set up.
3) The rotating position and speed
of the motor are detected by the
electromotive force occurred on
the motor winding with operation
of the compressor.
4) According to the difference
resulted from comparison of the
correction value of Hz signal with
the present operation Hz, the
inverter output and the commuta-
tion timing are varied.
5) Change the compressor motor
speed by outputting power to the
compressor.
* The contents of control
operation are same in cooling
operation and heating
operation
This function prevents troubles on the electronic parts of the
compressor driving inverter.
This function also controls drive circuit of the compressor
speed so that electric power of the compressor drive circuit
does not exceed the specified value.
5. Current release
control
Set temp. (Ts)
Room temp. (Ta)
Correction of Hz signal
Outdoor temp. To
Setup of current release point
Change of compressor speed
Remote controller
Indoor unit
Ts –Ta
Current decrease
Correction value of Hz signal
≤
Operating Hz
Outdoor unit inverter main
circuit control current
High
Low
Reduce compressor speed
Operating current
≤
Setup value
FILE NO. SVM-10029
Capacity control continues.
Outdoor tem p.
45°C
40°C
44°C
16°C
39°C
11°C
15.5°C
10.5°C
Cooling current
Heating current
release value
release value
3.97A
4.35A
6.30A
6.30A
6.30A
6.30A
1) The input current of the outdoor
unit is detected in the inverter
section of the outdoor unit.
2) According to the detected
outdoor temperature, the
specifice value of the current is
selected.
3) Whether the current value
exceeds the specifice value or
not is judged.
4) If the current value exceeds the
specified value, this function
reduces the compressor speed
and controls speed up to the
closest one commanded from the
indoor unit within the range
which does not exceed the
specified value.
