Danfoss VLT AQUA Design Manual page 23

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VLT AQUA Drive Design Guide
The following parameters are relevant for a simple PID control application:
Parameter
Feedback 1 Source
Reference/Feedback 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
par. 20-00 Select the source for Feedback 1. This is most commonly an 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 conversion 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).
par. 20-81 Select Normal [0] if the motor's speed should decrease when the feedback is greater than the
setpoint reference. Select
is greater than the setpoint reference.
par. 20-93 This parameter adjusts the output of the drive's closed loop controlled based on the error be-
tween the feedback and the setpoint reference. Quick controller response is obtained when this
value is large. However, if too large of a value is used, the drive's output frequency may become
unstable.
par. 20-94 The integrator adds over time (integrates) the error between the feedback and the setpoint
reference. This is required to ensure that the error approaches zero. Quick controller response
is obtained when this value is small. However, if too small of a value is used, the drive's output
frequency may become unstable. A setting of 10000 s disables the integrator.
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MG.20.N3.02 - VLT is a registered Danfoss trademark
2. Introduction to VLT AQUA Drive
Inverse [1] if the motor's speed should increase when the feedback
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