Danfoss FC 300 Programming Manual page 97

Parameter Descriptions
7-32 Process PID Start Speed
Range: Function:
0 RPM [0 - 6000 Enter the motor speed to be attained as a start
*
RPM] signal for commencement of PID control.
When the power is switched on, the frequency
converter will commence ramping and then
operate under speed open loop control.
Thereafter, when the Process PID start speed is
reached, the frequency converter will change
over to Process PID control.
7-33 Process PID Proportional Gain
Range: Function:
0.01 [0.00 - 10.00 ] Enter the PID proportional gain. The
*
proportional gain multiplies the error
between the set point and the feedback
signal.
7-34 Process PID Integral Time
Range: Function:
10000.00 s [0.01 - Enter the PID integral time. The
*
10000.00 s] integrator provides an increasing gain
at a constant error between the set
point and the feedback signal. The
integral time is the time needed by
the integrator to reach the same gain
as the proportional gain.
7-35 Process PID Differentiation Time
Range: Function:
0.00 s [0.00 - 10.00 Enter the PID differentiation time. The
*
s] differentiator does not react to a constant
error, but provides a gain only when the
error changes. The shorter the PID differen-
tiation time, the stronger the gain from the
differentiator.
7-36 Process PID Diff. Gain Limit
Range: Function:
5.0 [1.0 - 50.0 ] Enter a limit for the differentiator gain (DG). If
*
there is no limit, the DG will increase when
there are fast changes. Limit the DG to obtain a
pure differentiator gain at slow changes and a
constant differentiator gain where fast changes
occur.
7-38 Process PID Feed Forward Factor
Range: Function:
0 % [0 - Enter the PID feed forward (FF) factor. The FF factor
*
200 %] sends a constant fraction of the reference signal to
bypass the PID control, so the PID control only
affects the remaining fraction of the control signal.
Any change to this parameter will thus affect the
motor speed. When the FF factor is activated it
provides less overshoot, and high dynamics when
FC 300 Programming Guide
7-38 Process PID Feed Forward Factor
Range:
7-39 On Reference Bandwidth
Range:
5 %
3.9.5 7-4* Advanced Process PID Ctrl.
7-40 Process PID I-part Reset
Option:
[0]
[1]
7-41 Process PID Output Neg. Clamp
Range:
-100 %
7-42 Process PID Output Pos. Clamp
Range:
100 %
7-43 Process PID Gain Scale at Min. Ref.
Range:
100 %
7-44 Process PID Gain Scale at Max. Ref.
Range:
100 %
®
MG.33.M9.02 - VLT is a registered Danfoss trademark
Function:
changing the set point. par. 7-38 Process PID Feed
Forward Factor is active when par. 1-00 Configura-
tion Mode is set to [3] Process.
Function:
[0 - 200 Enter the On Reference bandwidth. When the
*
%] PID Control Error (the difference between the
reference and the feedback) is less than the set
value of this parameter the On Reference status
bit is high, i.e. =1.
Function:
No
*
Yes Select Yes [1] to reset the I-part of the process PID
controller. The selection will automatically revert to No
[0]. Resetting the I-part makes it possible to start from a
welldefined point after changing something in the
process, e.g. changing a textile roll.
Function:
[Application depend- Enter a negative limit for the
*
ant] process PID controller output.
Function:
[Application depend- Enter a positive limit for the
*
ant] process PID controller output.
Function:
[0 - 100 Enter a scaling percentage to apply to the
*
%] process PID output when operating at the
minimum reference. The scaling percentage
will be adjusted linearly between the scale at
min. ref. (par. 7-43 Process PID Gain Scale at Min.
Ref.) and the scale at max. ref. (par. 7-44 Process
PID Gain Scale at Max. Ref.).
Function:
[0 - 100 Enter a scaling percentage to apply to the
*
%] process PID output when operating at the
maximum reference. The scaling percentage
will be adjusted linearly between the scale at
min. ref. (par. 7-43 Process PID Gain Scale at Min.
Ref.) and the scale at max. ref. (par. 7-44 Process
PID Gain Scale at Max. Ref.).
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