Danfoss vlt FC 102 Programming Guide

3.18.3 20-3* Feedback Adv. Conversion
In air-conditioning compressor applications, it is often
useful to control the system based on the temperature of
the refrigerant. However, it is generally more convenient to
directly measure its pressure. This parameter group allows
the frequency converter’s PID controller to convert
refrigerant pressure measurements into temperature values.
20-30 Refrigerant
Option: Function:
Select the refrigerant used in the
compressor application. This
parameter must be specied
correctly for the pressure to
temperature conversion to be
accurate. If the refrigerant used is
not listed in options [0] through [6],
select [7] User dened. Then, use
parameter 20-31 User Dened
Refrigerant A1, parameter 20-32 User
Dened Refrigerant A2, and
parameter 20-33 User Dened
Refrigerant A3 to provide A1, A2,
and A3 for the equation below:
Temperature = 
A2
ln Pe + 1 − A1
− A3
[0] * R22
[1] R134a
[2] R404A
[3] R407C
[4] R410A
[5] R502
[6] R744
[7] User dened
20-31 User Dened Refrigerant A1
Range: Function:
10* [8 - 12 ] Use this parameter to enter the
value of coecient A1 when
parameter 20-30 Refrigerant is set to
[7] User dened.
20-32 User Dened Refrigerant A2
Range: Function:
-2250* [-3000 -
-1500 ]
Use this parameter to enter the
value of coecient A2 when
parameter 20-30 Refrigerant is set to
[7] User dened.
20-33 User Dened Refrigerant A3
Range: Function:
250* [200 - 300 ] Use this parameter to enter the
value of coecient A3 when
parameter 20-30 Refrigerant is set to
[7] User dened.
20-34 Duct 1 Area [m2]
Range: Function:
0.500 m2* [0.001 - 10
m2]
Used for setting the area of the air
ducts in connection with feedback
conversion pressure/velocity to
ow. The unit (m
2
) is determined by
the setting of
parameter 0-03 Regional Settings.
Fan 1 is used with feedback 1. In
case of ow dierence control, set
parameter 20-20 Feedback Function
to [1] Dierence, if ow fan 1 – ow
fan 2 is to be controlled.
20-35 Duct 1 Area [in2]
Range: Function:
750 in2* [1 - 15500
in2]
Used for setting the area of the air
ducts in connection with feedback
conversion pressure/velocity to
ow. The unit (in
2
) is determined by
the setting of
parameter 0-03 Regional Settings.
Fan 1 is used with feedback 1. In
case of ow dierence control, set
parameter 20-20 Feedback Function
to [1] Dierence, if ow fan 1 – ow
fan 2 is to be controlled.
20-36 Duct 2 Area [m2]
Range: Function:
0.500 m2* [0.001 - 10
m2]
Used for setting the area of the air
ducts in connection with feedback
conversion pressure/velocity to
ow. The unit (m
2
) is determined by
the setting of
parameter 0-03 Regional Settings.
Fan 2 is used with feedback 2. In
case of ow dierence control, set
parameter 20-20 Feedback Function
to [1] Dierence, if ow fan 1 – ow
fan 2 is to be controlled.
20-37 Duct 2 Area [in2]
Range: Function:
750 in2* [1 - 15500
in2]
Used for setting the area of the air
ducts in connection with feedback
conversion pressure/velocity to
ow. The unit (in
2
) is determined by
the setting of
parameter 0-03 Regional Settings.
Fan 2 is used with feedback 2. In
case of ow dierence control, set
parameter 20-20 Feedback Function
to [1] Dierence, if ow fan 1 – ow
fan 2 is to be controlled.
Parameter Descriptions Programming Guide
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Danfoss vlt FC 102 Specifications

General

Brand	Danfoss
Model	vlt FC 102
Category	DC Drives
Language	English