Danfoss VLT FC 102 Programming Manual page 185

Parameter Descriptions
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 specified
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 defined. Then, use
parameter 20-31 User Defined
Refrigerant A1, parameter 20-32 User
Defined Refrigerant A2, and
parameter 20-33 User Defined
Refrigerant A3 to provide A1, A2,
and A3 for the equation below:
Temperature =
[0] R22
*
[1] R134a
[2] R404A
[3] R407C
[4] R410A
[5] R502
[6] R744
[7] User defined
20-31 User Defined Refrigerant A1
Range: Function:
10 [8 - 12 ] Use this parameter to enter the
*
value of coefficient A1 when
parameter 20-30 Refrigerant is set to
[7] User defined.
20-32 User Defined Refrigerant A2
Range: Function:
-2250 [-3000 - Use this parameter to enter the
*
-1500 ] value of coefficient A2 when
parameter 20-30 Refrigerant is set to
[7] User defined.
20-33 User Defined Refrigerant A3
Range: Function:
250 [200 - 300 ] Use this parameter to enter the
*
value of coefficient A3 when
parameter 20-30 Refrigerant is set to
[7] User defined.
M0010001
Programming Guide
20-34 Duct 1 Area [m2]
Range:
0.500 m2
20-35 Duct 1 Area [in2]
Range:
750 in2
A2
− A3
ln Pe + 1 − A1
20-36 Duct 2 Area [m2]
Range:
0.500 m2
20-37 Duct 2 Area [in2]
Range:
750 in2
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Function:
[0.001 - 10 Used for setting the area of the air
*
m2] ducts in connection with feedback
conversion pressure/velocity to
flow. The unit (m
the setting of
parameter 0-03 Regional Settings.
Fan 1 is used with feedback 1. In
case of flow difference control, set
parameter 20-20 Feedback Function
to [1] Difference, if flow fan 1 – flow
fan 2 is to be controlled.
Function:
[1 - 15500 Used for setting the area of the air
*
in2] ducts in connection with feedback
conversion pressure/velocity to
flow. The unit (in
the setting of
parameter 0-03 Regional Settings.
Fan 1 is used with feedback 1. In
case of flow difference control, set
parameter 20-20 Feedback Function
to [1] Difference, if flow fan 1 – flow
fan 2 is to be controlled.
Function:
[0.001 - 10 Used for setting the area of the air
*
m2] ducts in connection with feedback
conversion pressure/velocity to
flow. The unit (m
the setting of
parameter 0-03 Regional Settings.
Fan 2 is used with feedback 2. In
case of flow difference control, set
parameter 20-20 Feedback Function
to [1] Difference, if flow fan 1 – flow
fan 2 is to be controlled.
Function:
[1 - 15500 Used for setting the area of the air
*
in2] ducts in connection with feedback
conversion pressure/velocity to
flow. The unit (in
the setting of
parameter 0-03 Regional Settings.
Fan 2 is used with feedback 2. In
case of flow difference control, set
parameter 20-20 Feedback Function
to [1] Difference, if flow fan 1 – flow
fan 2 is to be controlled.
3
2
) is determined by
2
) is determined by
2 ) is determined by
2 ) is determined by
183
3