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SiUS041501E
Control Specification
Function and Control
36
2. Determine upper limit frequency
The minimum value is set as an upper limit frequency among the frequency upper limits of the
following functions:
Compressor protection, input current, discharge pipe temperature, heating peak-cut, freeze-up
protection, defrost control.
3. Determine lower limit frequency
The maximum value is set as an lower limit frequency among the frequency lower limits of the
following functions:
Four way valve operation compensation, draft prevention, pressure difference upkeep.
4. Determine prohibited frequency
There is a certain prohibited frequency such as a power supply frequency.
Initial Frequency
When starting the compressor, the frequency is initialized according to the
∆
D value of the indoor
unit.
<
∆
D signal: Indoor frequency command>
The difference between the room thermistor temperature and the target temperature is recognized
as the
∆
D signal and is used for frequency command.
∗
OFF = Thermostat OFF
PI Control
1. P control
The
∆
D value is calculated in each sampling time (20 seconds), and the frequency is adjusted
according to its difference from the frequency previously calculated.
2. I control
If the operating frequency does not change for more than a certain fixed time, the frequency is
adjusted according to the
∆
D value.
When the
∆
D value is low, the frequency is lowered.
When the
∆
D value is high, the frequency is increased.
3. Frequency control when other controls are functioning
When frequency is dropping;
Frequency control is carried out only when the frequency drops.
For limiting lower limit;
Frequency control is carried out only when the frequency rises.
4. Upper and lower limit of frequency by PI control
The frequency upper and lower limits are set according to the command of the indoor unit.
When the indoor or outdoor unit quiet operation command comes from the indoor unit, the upper
limit frequency is lower than the usual setting.
Temperature
difference
∆
D
signal
Temperature
difference
∆
D
signal
Temperature
difference
∆
D
signal
Temperature
difference
∆
D
signal
–2.0°C (–3.6°F)
∗
OFF
0°C (0°F)
4
2.0°C (3.6°F)
8
4.0°C (7.2°F)
C
–1.5°C (–2.7°F)
1
0.5°C (0.9°F)
5
2.5°C (4.5°F)
9
4.5°C (8.1°F)
D
–1.0°C (–1.8°F)
2
1.0°C (1.8°F)
6
3.0°C (5.4°F)
A
5.0°C (9.0°F)
E
–0.5°C (–0.9°F)
3
1.5°C (2.7°F)
7
3.5°C (6.3°F)
B
5.5°C (9.9°F)
F
Summary of Contents for FTKN09NMVJU
Page 12: ...SiUS041501E 1 List of Functions Part 1 List of Functions 1 Functions 2...
Page 59: ...SiUS041501E Remote Controller 48 Part 5 Remote Controller 1 Cooling Only 49 2 Heat Pump 51...
Page 65: ...SiUS041501E Service Diagnosis 54 5 13 Power Module Check 100...
Page 132: ...Revision History Month Year Version Revised contents 03 2015 SiUS041501E First edition...