Si21-205
Outdoor Unit (25/35 class)
Function and Control
89
2.3
Frequency Control
Outline
Frequency will be determined according to the difference between room and set temperature.
The function is explained as follows.
1. How to determine frequency.
2. Frequency command from an indoor unit. (The difference between a room temperature and
the temperature set by the remote controller.)
3. Frequency command from an indoor unit.
4. Frequency initial setting.
5. PI control.
Detail
How to Determine Frequency
The compressor’s frequency will finally be determined by taking the following steps.
For Heat Pump Model
1. Determine command frequency
Command frequency will be determined in the following order of priority.
1.1 Limiting frequency by drooping function
Input current, discharge pipes, low Hz high pressure limit, peak cutting, freeze-up protection,
dew prevention, fin thermistor temperature.
1.2 Limiting defrost control time
1.3 Forced cooling
1.4 Indoor frequency command
2. Determine upper limit frequency
Set a minimum value as an upper limit frequency among the frequency upper limits of the
following functions:
Compressor protection, input current, discharge pipes, Low Hz high pressure, peak cutting,
freeze-up protection, defrost.
3. Determine lower limit frequency
Set a maximum value as an lower limit frequency among the frequency lower limits of the
following functions:
Four way valve operating compensation, draft prevention, pressure difference upkeep.
4. Determine prohibited frequency
There is a certain prohibited frequency such as a power supply frequency.
For Cooling Only Model
1. Determine command frequency
Command frequency will be determined in the following order of priority.
1.1 Limiting frequency by drooping function
Input current, discharge pipes, freeze-up protection, dew prevention, fin thermistor temperature.
1.2 Indoor frequency command
2. Determine upper limit frequency
Set a minimum value as an upper limit frequency among the frequency upper limits of the
following functions:
Compressor protection, input current, discharge pipes, freeze-up protection, dew prevention,
fin thermistor temperature.
Command frequency
Limit frequency
Skip control
Upper limit function
Compressor protection function
Lower limit function
Four-way valve operating compensation, etc. (*)
Initial frequency
PI control
Defrost control (*)
Drooping function
Input current control, etc.
Upper limit frequency
FMAX
Lower limit frequency
FMIN
Target frequency
Command frequency X repeats when frequency becomes lower
Frequency changes by PI control < repeats when frequency becomes lower
*; only for heat pump model
(R2831)
Содержание Sky Air B-Series R-410A
Страница 7: ...Si21 205 vi Table of Contents ...
Страница 15: ...Models Si21 205 4 Model Name and Power Supply ...
Страница 16: ...Si21 205 Functions 5 Part 2 Functions 1 List of Functions 6 ...
Страница 35: ...Wireless Remote Controller Si21 205 24 Remote Controller ...
Страница 77: ...Settings Concerning Maintenance Si21 205 66 Field Setting FHQ B Service monitor LED Capacity setting adaptor ...
Страница 79: ...Settings Concerning Maintenance Si21 205 68 Field Setting Detail of PCB 2 ...
Страница 83: ...Maintenance Mode Setting Si21 205 72 Field Setting ...
Страница 239: ...Troubleshooting for Outdoor Unit 50 60 class Si21 205 228 Troubleshooting ...
Страница 246: ...Si21 205 FFQ25 35 50 60BV1B Removal Procedure 235 4 Remove the horizontal vane Step Procedure Points S2646 ...
Страница 283: ...Outdoor Unit 25 35 class Si21 205 272 Removal Procedure 2 Slide the MID upward and release Step Procedure Points ...
Страница 285: ...Outdoor Unit 25 35 class Si21 205 274 Removal Procedure 4 Remove the fan motor Step Procedure Points ...
Страница 321: ...Outdoor Unit 50 60 class Si21 205 310 Removal Procedure ...