Danfoss VLT AQUA Drive Design Manual page 23

VLT ® AQUA Drive Design Guide
The following parameters are relevant for a simple PID control application:
Parameter
Feedback 1 Source par. 20-00 Select the source for Feedback 1. This is most commonly an
Reference/Feed-
back Unit
PID Normal/Inverse
Control
PID Proportional
Gain
PID Integral Time
This table summarizes the parameters that are needed to set up the drive's closed-loop controller
when a single feedback signal with no conversion is compared to a single setpoint. This is the
most common type of closed-loop controller.
Description of function
analog input, but other sources are also available. Use the
scaling of this input to provide the appropriate values for this
signal. By default, Analog Input 54 is the default source for
Feedback 1.
par 20-12 Select the unit for the setpoint reference and feedback for
the drive's closed-loop controller. Note: Because a conver-
sion can be applied to the feedback signal before it is used
by the closed-loop controller, the reference/feedback unit
(par. 20-12) may not be the same as the feedback source
unit (par. 20-02, 20-05 and 20-08).
Normal
par. 20-81 Select
when the feedback is greater than the setpoint reference.
Inverse
Select
when the feedback is greater than the setpoint reference.
par. 20-93 This parameter adjusts the output of the drive's closed-loop
control based on the error between the feedback and the
setpoint reference. Quick controller response is obtained
when this value is large. However, if a value that is too large
is used, the drive's output frequency may become unstable.
par. 20-94 Over time, the integrator adds (integrates) the error between
the feedback and the setpoint reference. This is required to
ensure that the error approaches zero. Quick controller re-
sponse is obtained when this value is small. However, if a
value that is too small is used, the drive's output frequency
may become unstable. A setting of 10,000 s disables the in-
tegrator.
MG.20.N2.22 - VLT ® is a registered Danfoss trademark.
2. Introduction to the VLT AQUA Drive
[0] if the speed of the motor should decrease
[1] if the speed of the motor should increase
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