General Functions
SiBE04-101
40
Main Function
1.19
Wet Operation Protection I (Securing of Differential Pressure and Blown Air
Temperature)
Outline
To secure the reliability of the compressor (for dryness of suction refrigerant and differential pressure)
which is the primary purpose of the compressor, the lower limit of the output frequency is limited to two
stages under the condition of outside air temperature. This time, in addition to this purpose, this function is
adopted also for prevention of cold draught by securing the blown air temperature at the time of heating
operation by low-temperature out side air.
Processing
1. at the first step
During operation of compressors.
Outdoor temperature
≤
DOA1CG
If
and
are under the simultaneous condition with AND, the lower limit of frequency in this function
is set at FCG7.
Compressors stop.
Outdoor temperature
≥
DOA2CG
If
and
are under the simultaneous condition with OR, the lower limit of frequency at the first step
control is cancelled.
2. at the second step
During operation of compressors
Outdoor temperature
≤
DOA3CG
If
and
are under the simultaneous condition with AND, the lower limit of frequency in this function
is set at FCG8.
Compressors stop.
Outdoor temperature
≥
DOA4CG
If
and
are under the coordinate condition with OR, the lower limit of frequency at the second step
control is cancelled.
3. The set of a constant
DOA1CG, DOA2CG, DOA3CG, FCG7 and FCG8 have constants for Cooling /Heating separately and
these constants are distinguished with a suffix c/w.
4. Actual constant
∗
DOA : Outdoor air temperature
CGC : Compressor guard for cooling
CGW : Compressor guard for heating
FCG : Frequency guard for compressor protection
(In cooling)
50 Class
60 Class
71 Class
(In heating)
50 Class
60 Class
71 Class
DOA1CGC
18˚C
18˚C
18˚C
DOA1CGW
0˚C
0˚C
0˚C
DOA2CGC
19˚C
19˚C
19˚C
DOA2CGW
2˚C
2˚C
2˚C
DOA3CGC
0˚C
0˚C
0˚C
DOA3CGW
-4˚C
-4˚C
-4˚C
DOA4CGC
1˚C
1˚C
1˚C
DOA4CGW
-2˚C
-2˚C
-2˚C
FCG7C
58 Hz
48 Hz
36 Hz
FCG7W
42 Hz
36 Hz
32 Hz
FCG8C
62 Hz
52 Hz
38 Hz
FCG7W
52 Hz
42 Hz
36 Hz
FCG8
The lower
frequency limit.
Cancelled
FCG7
FCG7
Cancelled
DOA3CG
DOA4CG
DOA1CG
DOA2CG
Outdoor temperature
(R1044)
SiBE04-101.book Page 40 Monday, October 15, 2001 3:08 PM
