18 function library – Lenze 8400 User Manual
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18
Function library
18.1
Function blocks | L_ProcessCtrl_1
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Lenze · 8400 protec HighLine · Reference manual · DMS 3.0 EN · 03/2013 · TD05
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Loading the setpoint ramp generator with the actual value
If the actual value is loaded into the setpoint ramp generator in switched-off state, it has the
advantage that in the moment of the renewed controller enable, the system deviation is zero first.
Thus, compensation processes can be mostly prevented.
When the bLoadAct input is set to TRUE, the setpoint ramp generator can be loaded with the actual
value. This keeps the system deviation equal to zero and I component of the controller.
Low pass and rate action in the actual value path
In order to filter signal interferences more effectively, you can activate a low pass in the actual value
path.
• The filter time constant for the low pass is set in
• The rate time constant in the feedback path can be set in
. This serves to compensate
interfering decelerations.
Reduced controller dynamics at low system deviation
Due to a reduced controller dynamics with low system deviations, the dampening behaviour of the
control loop is mostly influenced favourably.
•
serves to determine the tolerance zone in which the system deviation is transmitted
to the controller with a slight gain.
•
serves to determine the amount of percent the gain in the defined tolerance zone is
to be reduced to.