Danfoss VLT Automation Drive FC 360 Programming Manual page 73

Parameter Descriptions
7-41 Process PID Output Neg. Clamp
Range: Function:
-100 % [ -100 - 100 %] Enter a negative limit for the process
*
PID controller output.
7-42 Process PID Output Pos. Clamp
Range: Function:
100 % [ -100 - 100 %] Enter a positive limit for the process
*
PID controller output.
7-43 Process PID Gain Scale at Min. Ref.
Range: Function:
100 % [0 - Enter a scaling percentage to apply to the
*
100 %] process PID output when operating at the
minimum reference. The scaling percentage is
adjusted linearly between the scale at
minimum reference (parameter 7-43 Process PID
Gain Scale at Min. Ref.) and the scale at
maximum reference (parameter 7-44 Process
PID Gain Scale at Max. Ref.).
7-44 Process PID Gain Scale at Max. Ref.
Range: Function:
100 % [0 - Enter a scaling percentage to apply to the
*
100 %] process PID output when operating at the
maximum reference. The scaling percentage is
adjusted linearly between the scale at
minimum reference (parameter 7-43 Process PID
Gain Scale at Min. Ref.) and the scale at
maximum reference (parameter 7-44 Process
PID Gain Scale at Max. Ref.).
7-45 Process PID Feed Fwd Resource
Option: Function:
Select which frequency converter input
is used as the feed forward factor. The
FF factor is added directly to the
output of the PID controller. This
parameter can increase dynamic
performance.
[0] No function
*
[1] Analog Input 53
[2] Analog Input 54
[7] Frequency input 29
[8] Frequency input 33
[11] Local bus reference
[32] Bus PCD
7-46 Process PID Feed Fwd Normal/ Inv. Ctrl.
Option: Function:
[0] Normal Select [0] Normal to set the feed forward factor to
*
treat the FF resource as a positive value.
[1] Inverse Select [1] Inverse to treat the feed forward resource
as a negative value.
MG06C602
Programming Guide
7-48 PCD Feed Forward
Range:
0 [0 - 65535 ] Readout parameter where the bus
*
7-49 Process PID Output Normal/ Inv. Ctrl.
Option:
[0] Normal Select [0] Normal to use the resulting output from
*
[1] Inverse Select [1] Inverse to invert the resulting output
4.8.6 7-5* Ext. Process PID Ctrl.
This parameter group is only used if parameter 1-00 Config-
uration Mode is set to [7] Extended PID speed CL.
7-50 Process PID Extended PID
Option:
[0] Disabled Disables the extended parts of the process PID
[1] Enabled Enables the extended parts of the PID controller.
*
7-51 Process PID Feed Fwd Gain
Range:
1 [0 -
*
100 ]
7-52 Process PID Feed Fwd Ramp up
Range:
0.01 s
*
7-53 Process PID Feed Fwd Ramp down
Range:
0.01 s
*
7-56 Process PID Ref. Filter Time
Range:
0.001 s
*
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Function:
parameter 7-45 Process PID Feed Fwd Resource
[32] can be read.
Function:
the process PID controller as is.
from the process PID controller. This operation is
performed after the feed forward factor is applied.
Function:
controller.
Function:
The feed forward is used to obtain the level, based
on a well-known signal available. The PID controller
then only takes care of the smaller part of the
control, necessary because of unknown characters.
The standard feed forward factor in
parameter 7-38 Process PID Feed Forward Factor is
always related to the reference whereas
parameter 7-51 Process PID Feed Fwd Gain has more
options. In winder applications, the feed forward
factor is typically the line speed of the system.
Function:
[0.01 - 100 s] Controls dynamics of the feed forward
signal when ramping up.
Function:
[0.01 - 100 s] Controls the dynamics of the feed
forward signal when ramping down.
Function:
[0.001 - 1 Set a time constant for the reference first-
s] order low-pass filter. The low-pass filter
improves steady-state performance and
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