Sanyo Big PACi 18 Series Technical Data & Service Manual page 206

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.
* 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.
Maximum Frequency
Minimum Frequency
* 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.
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.
(1) Current release control with primary current : The limited values are modified in accordance with outdoor
Diagram of Current Release Control
with Outdoor Air Temperature
TO (Outdoor Air Temperature)
A
B
C
D
E
F
G
H
(2) Current release control with secondary current : Values are fixed regardless of outdoor air temperature.
706 Model
I (A) 14.5
4) Cooling High-Load Prevention Control
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)
64
a
b
c
d
706 Model
Cooling 91.2 Hz
Heating 96.0 Hz
Cooling 25.0 * Hz
Heating 25.0 * Hz
air temperature.
Cooling Mode
TO 706 and 906 Models
A
B
ls a
C
D
ls b
E
ls c
F
G
ls d
H
ls
906 Model
15.5
Outdoor unit operations halted
Frequency decreased
Frequency increases prevented
Frequency increased slower than normal
Normal operations (no control)
906 Model
80.0 Hz
85.0 Hz
25.0 * Hz
25.0 * Hz
48 Is
47
45 Is a
44 Is b
43 Is c
42 Is d
40
39
a
b
c
d
4-3
706 Model 906 Model
12.5 15.0
Current value Current value
6.3 7.5
7.5 9.0
8.8 10.5
10.6 12.8
706 Model 906 Model
55 53
54 52
52 50
48 47
4