Danfoss VLT HVAC Series, Programming Manual, Page: 197 / 338

20-13 Minimum Reference/Feedb.
Range: Function:
0.000 Proc-
essCtrlU-
nit* [-999999.999 - par. 20-14 Proc-
essCtrlUnit] Enter the desired minimum value for the remote reference when operating with par. 1-00, Config-
uration Mode set for Closed-loop [3] operation. Units are set in par. 20-12, Reference/Feedback
Unit.
Minimum feedback will be -200% of either the value set in par. 20-13 or in par. 20-14, which ever
numeric value is the highest.
NOTE!
If operating with par.1-00, Configuration Mode set for Open-loop [0], par. 3-02,
Minimum Reference must be used.
20-14 Maximum Reference/Feedb.
Range: Function:
100.000
ProcessCtr-
lUnit* [par. 20-13 - 999999.999 Proc-
essCtrlUnit] Enter the maximum reference/feedback for closed-loop operation. The setting determines the high-
est value obtainable by summing all reference sources for closed-loop operation. The setting
determines 100% feedback in open-loop and closed-loop (total feedback range: -200% to +200%).
NOTE!
If operating with par.1-00
Configuration Mode
set for Open-loop [0], par.3-03
Maximum Reference
must be used.
NOTE!
The dynamics of the PID controller will depend on the value set in this parameter. Please also see par.20-93
PID Proportional Gain
.
Par. 20-13 and par. 20-14 also determine the feedback range when using feedback for display readout with par.1-00
Configuration
Mode
set for Open-loop [0]. Same condition as above.
3.18.3 20-2* Feedback & Setpoint
This parameter group is used to determine how the adjustable frequency drive’s PID controller will use the three possible feedback signals to control the
output frequency of the adjustable frequency drive. This group is also used to store the three internal setpoint references.
20-20 Feedback Function
Option: Function:
This parameter determines how the three possible feedbacks will be used to control the output
frequency of the adjustable frequency drive.
[0] Sum
Sum
[0] sets up the PID controller to use the sum of Feedback 1, Feedback 2 and Feedback 3 as
the feedback.
NOTE!
Any unused feedbacks must be set to No Function in par.20-00 Feedback 1
Source , par.20-03 Feedback 2 Source , or par.20-06 Feedback 3 Source .
The sum of Setpoint 1 and any other references that are enabled (see par. group 3-1*) will be used
as the PID controller’s setpoint reference.
VLT ® HVAC Drive Programming Guide 3 Parameter Description
MG.11.C6.22 - VLT ® is a registered Danfoss trademark
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