20-08 Feedback 3 Source Unit
Option:
Function:
See
20-02 Feedback 1 Source Unit
for details.
20-12 Reference/Feedback Unit
This parameter determines the unit that is used for the setpoint
reference and feedback that the PID Controller will use for
controlling the output frequency of the frequency converter.
Option:
Function:
[60]
*
°C
[160]
°F
3.15.2 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:
Function:
This parameter 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 parameter 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 parameter
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.
20-20 Feedback Function
Option:
Function:
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
parameter group 3-1*) will be used as the
PID Controller’s set-point reference.
[3]
*
Minimum
[3] Minimum
sets up the PID Controller to com
Feedback 1, Feedback 2 and Feedback 3 and
use the lowest value as the feedback.
NOTE
Any unused feedbacks must be set to
[0]
No Function
in
, or
. Only setpoint 1 will be used. The
sum of Setpoint 1 and any other
references that are enabled (see parameter
group 3-1*) will be used as the PID
Controller’s setpoint reference.
[4] Maximum
Maximum
[4] sets up the PID Controller to com
Feedback 1, Feedback 2 and Feedback 3 and
use the highest value as the feedback.
NOTE
Any unused feedbacks must be set to
No
Function
in
,
, or
Only Setpoint 1 will be used. The sum of
Setpoint 1 and any other references that are
enabled (see parameter group 3-1*) will be used
as the PID Controller’s setpoint reference.
[5] Multi
Setpoint
Min
[5] Multi-setpoint minimum
sets up the PID
Controller to calculate the difference between
Feedback 1 and Setpoint 1, Feedback 2 and
Setpoint 2, and Feedback 3 and Setpoint 3. It
will use the feedback/setpoint pair in which the
feedback is the farthest below its corresponding
setpoint reference. If all feedback signals are
above their corresponding setpoints, the PID
Controller will use the feedback/setpoint pair in
which the difference between the feedback and
setpoint is the least.
Parameter Description
VLT
®
Refrigeration Drive Programming Guide
114
MG16H102 - VLT
®
is a registered Danfoss trademark
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