Danfoss VLT FC 100 Series Programming Manual page 157

®
VLT HVAC Drive Programming Guide
[127] 3
ft /h
[130] lb/s
[131] lb/min
[132] lb/h
[140] ft/s
[141] ft/min
[145] ft
[160] °F
[170] psi
[171] 2
lb/in
[172] in WG
[173] ft WG
[180] HP
20-13 Minimum Reference/Feedb.
Range:
*
0 [-1000000 to par. 20-14]
20-14 Maximum Reference/Feedb.
Option:
* Par. 20-13 to 1000000
[100.000]
3.18.3. 20-2* Feedback & Setpoint
This parameter group is used to determine how the frequency converter's PID Controller will use the three possible feedback signals to control the output
frequency of the frequency converter. This group is also used to store the three internal setpoint references.
20-20 Feedback Function
Option:
[0] Sum
[1] Difference
[2] Average
Function:
Enter the minimum reference/feedback value for closed loop operation. The setting determines the lowest value
obtainable by summing all reference sources. The setting determines 0% feedback in open and closed loop (total
feedback range: -200% to +200%).
Function:
Enter the maximum reference/feedback for closed loop operation. The setting determines the highest value
obtainable by summing all reference sources for closed loop operation. The setting determines 100% feedback
in open and closed loop (total feedback range: -200% to +200%).
Function:
This parameter determines how the three possible feedbacks will be used to control the output frequency of the
frequency converter.
Sum [0] sets up the PID Controller to use the sum of Feedback 1, Feedback 2 and Feedback 3 as the feedback.
NB!
Any unused feedbacks must be set to
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.
Difference
[1] sets up the PID Controller to use the difference between Feedback 1 and Feedback 2 as the
feedback. Feedback 3 will not be used with this selection. Only setpoint 1 will be used. 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.
Average
[2] sets up the PID Controller to use the average of Feedback 1, Feedback 2 and Feedback 3 as the
feedback.
MG.11.C5.02 - VLT ® is a registered Danfoss trademark
3. Parameter Description
No Function
in par. 20-00, par. 20-03, or par. 20-06.
3
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