Danfoss VLT FC 103 Programming Manual page 114

Parameter Description
NOTE
If a feedback is not used, its source must be set to [0] No
Function. 20-20 Feedback Function determines how the
three possible feedbacks will be used by the PID
Controller.
20-01 Feedback 1 Conversion
This parameter allows a conversion function to be applied to
Feedback 1.
Option: Function:
[0] Linear Linear [0] has no effect on the feedback.
[1] Square root Square root [1] is commonly used when a
pressure sensor is used to provide flow
feedback ((
[2] Pressure to Pressure to temperature [2] is used in
temperature compressor applications to provide
*
temperature feedback using a pressure
sensor. The temperature of the refrigerant is
calculated using the following formula:
Temperature =
A1, A2 and A3 are refrigerant-specific
constants. The refrigerant must be selected
in 20-30 Refrigerant. 20-31 User Defined
Refrigerant A1 through 20-33 User Defined
Refrigerant A3 allow the values of A1, A2
and A3 to be entered for a refrigerant that
is not listed in 20-30 Refrigerant.
20-02 Feedback 1 Source Unit
This parameter determines the unit that is used for this Feedback
Source, prior to applying the feedback conversion of
20-01 Feedback 1 Conversion. This unit is not used by the PID
Controller. It is used only for display and monitoring purposes.
Option:
[70] mbar
[71] bar
*
[72] Pa
[73] kPa
[74] m WG
[170] psi
[171]
lb/in 2
[172] in WG
[173] ft WG
NOTE
This parameter is only available when using Pressure to
Temperature Feedback Conversion.
20-03 Feedback 2 Source
Option: Function:
See 20-00 Feedback 1 Source for
details.
[0] No function
*
[1] Analog Input 53
®
VLT Refrigeration Drive Programming Guide
flow ∝ pressure )).
A 2
, where
− A 3
( ln ( Pe + 1 ) − A 1 )
Function:
®
MG16H102 - VLT is a registered Danfoss trademark
20-03 Feedback 2 Source
Option: Function:
[2] Analog Input 54
[3] Pulse input 29
[4] Pulse input 33
[7] Analog Input X30/11
[8] Analog Input X30/12
[9] Analog Input X42/1
[10] Analog Input X42/3
[11] Analog Input X42/5
[100] Bus Feedback 1
[101] Bus Feedback 2
[102] Bus feedback 3
20-04 Feedback 2 Conversion
Option: Function:
See 20-01 Feedback 1 Conversion
for details.
[0] Linear
*
[1] Square root
[2] Pressure to temperature
20-05 Feedback 2 Source Unit
Option: Function:
See 20-02 Feedback 1 Source Unit for details.
20-06 Feedback 3 Source
Option: Function:
See 20-00 Feedback 1 Source for
details.
[0] No function
*
[1] Analog Input 53
[2] Analog Input 54
[3] Pulse input 29
[4] Pulse input 33
[7] Analog Input X30/11
[8] Analog Input X30/12
[9] Analog Input X42/1
[10] Analog Input X42/3
[11] Analog Input X42/5
[100] Bus Feedback 1
[101] Bus Feedback 2
[102] Bus feedback 3
20-07 Feedback 3 Conversion
Option: Function:
See 20-01 Feedback 1 Conversion
for details.
[0] Linear
*
[1] Square root
[2] Pressure to temperature
3 3
113