Delphin ProfiMessage, Hardware Manual

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Profi Message
Typical formula for a standard PID controller:
Characteristic control system values
KS – process gain. dX/dY of a system step response.
Tu – delay time
Tg – compensation time
Tt – dead time
W – inflection point
KI – integral gain
TI – integral time
4.7.14.1.2
Control paths
To find a suitable controller, you must know the characteristics of the control paths
to be influenced.
A control path is that part of a system between the final control element for the con-
trol quantity (the process quantity to be controlled) and the control quantity's
measuring point. The final control element and the measuring element are also
part of the control path.
Control paths can be fundamentally divided into two categories:
l
Control paths with compensation: When a control or interference variable
changes, the control variable searches for a new final value (steady state).
Example: Flow, temperature, etc.
l
Control paths without compensation: Control paths that do not search for a
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 sys-
tems correspond to nth order control paths.
Control paths with compensation have the following char-
acteristics:
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Delphin Technology AG
Dezember 2015
Profi Message Manual