Daikin SiEN04-306D, Service Manual

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Control Specification SiEN04-306D
58 Function and Control
3.2 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 control.)
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 prevention,
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 prevention, 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 prevention, 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 prevention, dew prevention,
fin thermistor temperature.
Comm a nd fre qu ency
Limit frequency S kip control
Upper limit f u nction
Compre ss or protection f u nction
Lower limit f u nction
Fo u r-w a y v a lve oper a ting compen sa tion, etc. ( * )
Initi a l fre qu ency
PI control
Defro s t control ( * )
Drooping f u nction
Inp u t c u rrent control, etc.
Upper limit frequency
FMAX
Lower limit frequency
FMIN
Tar g et frequency
* ; only for he a t p u mp model
(R2 83 1)
Fre qu ency ch a nge s b y PI control < repe a t s when fre qu ency b ecome s lower
Comm a nd fre qu ency X repe a t s when fre qu ency b ecome s lower