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Si12-619A
Control Specification
Function and Control
101
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.
3. Determine lower limit frequency
Set a maximum value as an lower limit frequency among the frequency lower limits of the
following functions:
Pressure difference upkeep.
4. Determine prohibited frequency
There is a certain prohibited frequency such as a power supply frequency.
Indoor Frequency Command (
∆
D signal)
The difference between a room temperature and the temperature set by the remote controller
will be taken as the “
∆
D signal” and is used for frequency command.
∗
Th OFF = Thermostat OFF
Indoor Unit Capacity (S value)
The capacity of the indoor unit is a “S” value and is used for frequency command.
Frequency Initial Setting
<Outline>
When starting the compressor, or when conditions are varied due to the change of the operating
room, the frequency must be initialized according to the total of a maximum
∆
D value of each room
and a total value of Q (
Σ
Q) of the operating room (the room in which the thermostat is set to ON).
Q value: Indoor unit output determined from indoor unit volume, air flow rate and other factors.
PI Control
(Determine Frequency Up / Down by
∆
D Signal)
1. P control
Calculate a total of the
∆
D value in each sampling time (20 seconds), and adjust the
frequency according to its difference from the frequency previously calculated.
2. I control
If the operating frequency is not change more than a certain fixed time, adjust the frequency
up and down according to the
Σ∆
D value, obtaining the fixed
Σ∆
D value.
When the
Σ∆
D value is small...lower the frequency.
When the
Σ∆
D value is large...increase the frequency.
3. Limit of frequency variation width
When the difference between input current and input current drooping value is less than 1.5
A, the frequency increase width must be limited.
Temperature
difference
∆
D
signal
Temperature
difference
∆
D
signal
Temperature
difference
∆
D
signal
Temperature
difference
∆
D
signal
0
∗
Th
OFF
2.0
4
4.0
8
6.0
C
0.5
1
2.5
5
4.5
9
6.5
D
1.0
2
3.0
6
5.0
A
7.0
E
1.5
3
3.5
7
5.5
B
7.5
F
Capacity
S value
Capacity
S value
2.5 kW
25
6.0 kW
60
3.5 kW
35
7.1 kW
71
5.0 kW
50
Summary of Contents for 3MKS50DVM
Page 13: ...Introduction Si12 619A xii ...
Page 131: ...Control Specification Si12 619A 118 Function and Control ...
Page 213: ...Instruction Si12 619A 200 Operation Manual ...
Page 283: ...Check Si12 619A 270 Service Diagnosis ...
Page 302: ...Si12 619A Outdoor Unit E Series 50 52 58 Class Removal Procedure 289 Step Procedure Points ...
Page 385: ...Wiring Diagrams Si12 619A 372 Appendix FTK X S50 60 71FVLT ...
Page 399: ...Si12 619A vi Index ...