Sanyo Big PACi 18 Series - Page 206

4-3
4
2) Maximum and Minimum Frequency Control
The compressor's inverter frequency is controlled in accordance with the model and operation mode.
The maximum and minimum frequencies for each model are shown in the chart below.
3) Current Release Control
The inverter frequency is controlled so that the current value for the inverter compressor is less than the figure
listed in the chart below only in the cooling mode in order to prevent abnormal increases in the inverter circuit
located within the outdoor unit's electrical box.
4) Cooling High-Load Prevention Control
There are cases in which frequency is limited with other control functions depending on operational conditions,
so operations are not always carried out in accordance with the maximum frequencies listed below.
*
* There are cases in which the frequency is set at 33.0Hz to protect the compressor in accordance with outdoor
air temperature and indoor loads.
706 Model 906 Model
91.2 Hz
Maximum Frequency
Cooling
Heating Hz96.0
Hz25.0 *
Minimum Frequency
Cooling
Heating Hz
80.0 Hz
85.0 Hz
25.0 * Hz
25.0 *
Hz25.0 *
TO 706 and 906 Models
Cooling Mode
(1)
Diagram of Current Release Control
with Outdoor Air Temperature
TO (Outdoor Air Temperature)
ls a
ls b
ls c
ls d
ls
A
B
C
D
E
F
G
H
Current release control with primary current : The limited values are modified in accordance with outdoor
air temperature.
(2) Current release control with secondary current : Values are fixed regardless of outdoor air temperature.
H
G
F
E
D
C
B
A
39
40
42
43
44
45
47
48
706 Model
Is d
Is c
Is b
Is a
10.6
8.8
7.5
6.3
Current value
906 Model
12.8
10.5
9.0
7.5
Current value
Is 12.5 15.0
d
c
b
a
48
52
54
55
706 Model
47
50
52
53
906 Model
706 Model 906 Model
I (A) 14.5 15.5
This control is performed to limit the inverter frequency in order to restrict abnormal increases in pressure and
high-load operations in the cooling mode. In accordance with the temperature of the outdoor heat exchanger
temperature sensors (C1, C2), such controls are performed as halting the operations of the indoor unit,
decreasing the inverter frequency and restricting its increase, etc. If the temperature max (C1, C2) exceeds
64 , operations of the indoor unit are halted and then restarted 3 minutes later. If this start/stop activity is
repeated four times consecutively, alarm "P20" (cooling high-load error) occurs.
max. (C2, C1)
Outdoor unit operations halted
Frequency decreased
Frequency increases prevented
Frequency increased slower than normal
Normal operations (no control)
a
64
b
c
d
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