Endress+Hauser Liquiline System CA80HA, Руководство по эксплуатации

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Operation Liquiline System CA80HA
128 Hauser
Menu/Setup/Additional functions/Controller 1 ... 2
Function Options Info
Process type Selection
• Inline
• Batch
Factory setting
Inline
‣
Decide what type of process best describes
your particular process.
Batch process
The medium is in a closed system.
The task of the control system is to dose in such a way that the measured value (controlled variable) changes from its
start value to its target value. No more dosing is needed once the set point has been reached and the system is stable. If
the target value is overshot, a two-sided control system can compensate for this. In the case of 2-sided batch control
systems, a neutral zone is used/configured to suppress oscillations around the set point.
In-line process
In an in-line process, the control system works with the medium flowing by in the process.
Here, the controller has the task of using the manipulated variable to set a mixture ratio between the medium and
dosing agent such that the resulting measured variable corresponds to the set point. The properties and volume of the
medium flow can change at any time and the controller has to react to these changes on a continuous basis. If the flow
rate and medium remain constant, the manipulated variable can also assume a fixed value once the process has settled.
Since the control process is never "finished" here, this type of control is also referred to as continuous control.

A mixture of both process types can often be found in practice: the semi ‐ batch process. Depending on the ratio
between the flow and the container volume, this arrangement behaves either like a batch process or an in-line
process.
Controller type Selection
• PID 1-sided
• PID 2-sided
Factory setting
PID 2-sided
Depending on which actuator you have
connected, you influence the process in only
one direction (e.g . heating) or in both
directions (e. g. heating and cooling).
A 2
‐
sided controller can output a manipulated variable in the range from -100 % to +100 %, i. e. the manipulated
variable is bipolar. The manipulated variable is positive if the controller should increase the process value. In the case
of a pure P-controller, this means that the value of the controlled variable x is smaller than the set point w. On the
other hand, the manipulated variable is negative if the process value should be decreased. The value for x is greater
than the set point w.
y
+100 %
0 %
-100 %
x < w
w
x > w
x
X
p
X
p
 71 Relationship y = (w-x)/X
p