20-20 Feedback Function
Option: Function:
[1] Dierence Sets up the PID controller to use the dierence
between feedback 1 and feedback 2 as the
feedback. Feedback 3 is not used with this
selection. Only setpoint 1 is used. The sum of
setpoint 1 and any other references that are
enabled (see parameter group 3-1* References)
are used as the setpoint reference of the PID
controller.
[2] Average Sets up the PID controller to use the average of
feedback 1, feedback 2, and feedback 3 as the
feedback.
[3] Minimum Sets up the PID controller to compare feedback
1, feedback 2, and feedback 3, and use the
lowest value as the feedback. Only setpoint 1 is
used. The sum of setpoint 1 and any other
references that are enabled (see parameter
group 3-1* References) are used as the setpoint
reference of the PID controller.
[4]
*
Maximum Sets up the PID controller to compare feedback
1, feedback 2, and feedback 3, and use the
highest value as the feedback.
Only setpoint 1 is used. The sum of setpoint 1
and any other references that are enabled (see
parameter group 3-1* References) are used as the
setpoint reference of the PID controller.
[5] Multi
Setpoint
Min
Sets up the PID controller to calculate the
dierence between feedback 1 and setpoint 1,
feedback 2 and setpoint 2, and feedback 3 and
setpoint 3. It uses 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 uses the feedback/setpoint
pair in which the dierence between the
feedback and setpoint is the least.
NOTICE
If only 2 feedback signals are used, the
feedback that is not to be used must be
set to [0] No Function in
parameter 20-00 Feedback 1 Source,
parameter 20-03 Feedback 2 Source, or
parameter 20-06 Feedback 3 Source. Each
setpoint reference is the sum of its
respective parameter value and any other
references that are enabled (see
parameter group 3-1* References).
[6] Multi
Setpoint
Max
Sets up the PID controller to calculate the
dierence between feedback 1 and setpoint 1,
feedback 2 and setpoint 2, and feedback 3 and
setpoint 3. It uses the feedback/setpoint pair in
which the feedback is farthest above its
20-20 Feedback Function
Option: Function:
corresponding setpoint reference. If all feedback
signals are below their corresponding setpoints,
the PID controller uses the feedback/setpoint
pair in which the dierence between the
feedback and the setpoint reference is the least.
NOTICE
If only 2 feedback signals are used, the
feedback that is not to be used must be
set to [0] No Function in
parameter 20-00 Feedback 1 Source,
parameter 20-03 Feedback 2 Source, or
parameter 20-06 Feedback 3 Source. Each
setpoint reference is the sum of its
respective parameter value
(parameter 20-21 Setpoint 1,
parameter 20-22 Setpoint 2, and
parameter 20-23 Setpoint 3) and any other
references that are enabled (see
parameter group 3-1* References).
20-21 Setpoint 1
Range: Function:
0
ProcessCtrlUnit*
[-999999.999 -
999999.999
ProcessCtrlUnit]
Setpoint 1 is used in closed-
loop mode to enter a setpoint
reference that is used by the
frequency converter’s PID
controller. See the description
of parameter 20-20 Feedback
Function.
NOTICE
The setpoint reference
entered here is added to
any other references that
are enabled (see
parameter group 3-1*
References).
Parameter Description
VLT
®
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