Endress+Hauser Liquiline CM44P - Page 110

Operation Liquiline CM44P
110 Endress+Hauser
Menu/Setup/Additional functions/Controller 1 ... 2
Function Options Info
Effective direction
Controller type = PID 1-sided
Selection
• Direct
• Reverse
Factory setting
Reverse
In what direction should the controller influence
the measured value?
• The measured value should increase as a
result of dosing (e. g. heating)
→ Reverse
• The measured value should decrease as a
result of dosing (e. g. cooling)
→ Direct
A 1‐sided controller has a unipolar manipulated variable, i. e. it can only influence the process in one direction.
Reverse: If the controller should increase the process value, set this as the direction of action. The controller
becomes active when the process value is too small (range A).
Direct: With this direction of action, the controller acts as a "downwards controller". It becomes active when the
process value (e. g. the temperature) is too high (range B).
y
+100 %
0 %
-100 %
w
x
X
p
X
p
A
B
 94 Red: overlap between the curves of the two 1 ‐ sided controllers.
Controlled variable
Source of data Selection
• None
• Sensor inputs
• Current inputs
• Fieldbus signals
• Binary inputs
• Mathematical functions
Factory setting
None
‣
Specify the input or output which should be
the source of data for the controlled variable.
Measured value Selection
Depends on Source of data
Factory setting
None
‣
Specify the measured value that should be
your controlled variable.
You can use different measured values
depending on the data source. →  100
Setpoint Target value of the controlled variable
This menu is not displayed if you selected a
fieldbus as the source (Source of data =
fieldbus).
Setpoint Range of adjustment and
factory setting depending
on the Source of data
‣
Specify the target value for the controlled
variable.
Tw
Setup Level = Advanced
0.0 to 999.9 s
Factory setting
2.0 s
Time constant for the set point damping filter
Disturbance variable

optional, activation code necessary