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20-12 Reference/Feedback Unit
Option:
Function:
See
for details.
20-13 Minimum Reference/Feedb.
Range:
Function:
0.000
ProcessCtrlUnit
*
[ -999999.999 -
par. 20-14
ProcessCtrlUnit]
Enter the desired minimum
value for the remote
reference when operating
with
set for Closed Loop
[3] operation. Units are set
in
20-12 Reference/Feedback
Unit
.
Minimum feedback will be
-200% of either the value
set in
or in
20-14 Maximum Reference/
Feedb.
, which ever numeric
value is the highest.
NOTE
If operating with
set for Open
Loop [0],
must be used.
20-14 Maximum Reference/Feedb.
Range:
Function:
100.000
ProcessCtrlUnit
*
[ par. 20-13 -
999999.999
ProcessCtrlUnit]
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%).
NOTE
If operating with
set for Open
Loop [0],
3-03 Maximum Reference
must be used.
NOTE
The dynamics of the PID controller will depend on the
value set in this meter. Please see also
.
20-13 Minimum Reference/Feedb.
and
also determine the feedback range when
using feedback for display readout with
set for Open Loop [0]. Same condition as above.
3.18.2 20-2* Feedback & Setpoint
This meter 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:
Function:
This meter determines how the three possible
feedbacks will be used to control the output
frequency of the frequency converter.
[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
,
, or
The sum of Setpoint 1 and any other references
that are enabled (see meter group 3-1*) will be
used as the PID Controller’s set-point reference.
[1] Difference
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 meter group
3-1*) will be used as the PID controller’s set-
point reference.
[2] Average
Average
[2] sets up the PID Controller to use the
average of Feedback 1, Feedback 2 and
Feedback 3 as the feedback.
NOTE
Any unused feedbacks must be set to
No
Function
in
,
, or
. The sum of Setpoint 1 and any
other references that are enabled (see
meter group 3-1*) will be used as the PID
Controller’s set-point reference.
[3]
*
Minimum
Minimum
[3] sets up the PID Controller to com
Feedback 1, Feedback 2 and Feedback 3 and
use the lowest value as the feedback.
Parameter Description
VLT
®
HVAC Drive Programming Guide
MG.11.CC.02 - VLT
®
is a registered Danfoss trademark
131
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