Delphin Expert Logger Manual page 142

Expert Logger
Control paths without compensation: Control paths that do not search for a
l
final value (integrating control paths), are known as control paths without
compensation. Example: Fill level.
Most control paths consist of P systems (amplification/attenuation), one or
more T1 systems (lowpass) and if possible one dead time (run time). Paths
with P T1 properties are called first order control paths. Control paths with
multiple T1 systems correspond to nth order control paths.
Control paths with compensation have the following char-
acteristics:
The controllability of such a control path by a PID controller can be estim-
ated as follows:
Tg / Tu > 10: easy controllability
Tg / Tu > 6: medium controllability
Tg / Tu < 3: poor controllability
For control paths with dead time, Tg / (Tt + Tu) defines the controllability..
Step response of control path without compensation:
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142
Expert Logger Manual
Januar 2018