Endress+Hauser Liquiline System CA80NO, Руководство по эксплуатации

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Liquiline System CA80NO Operation
Hauser 99
integral section (middle) also comprises an anti
‐
windup mechanism for limiting the
integrator. A low-pass filter is added to the D
‐
section to damp hard D
‐
terms in the
manipulated variable. The sum of the 3 sections results in the internal controller
manipulated variable which is limited according to the settings (for PID
‐
2s to
‐
100% to
+100%).
The graphic does not illustrate a downstream filter for limiting the rate of change of the
manipulated variable (can be configured in the menu in Max y change rate ).
In the menu do not configure the gain K
p
. Instead configure the reciprocal value, the
proportional band X
p
(K
p
=1/X
p
).
Configuration
Make the following decisions to configure a controller:
• (1) What type of process can your process be assigned to? → Process type
• (2) Should it be possible to influence the measured variable (controlled variable) in one
direction or in both directions? One-sided or two-sided controller, → Controller type
• (3) What should be the controlled variable (sensor, measured value)? → Controlled
variable
• (4) Do you have a disturbance variable that should be active at the controller output? →
Disturbance variable
• (5) Specify the parameters for the controller:
• Set point, → Setpoint
• Neutral zone, → Xn
• Proportional band, → Xp
• Integral action time (I-value), → Tn
• Derivative action time (D-value), → Tv
• (6) What should the controller do in the event of a hold (measured error, sensor
replacement, cleaning etc.)?
• Pause or continue with dosing? → Hold behavior / Manipulated Variable
• At the end of a hold, continue or restart the control loop (affects I ‐ value)? → Hold
behavior / State
• (7) How should the actuator be triggered?
• U : assign this setting to the output for an actuator which can increase the
measured value.
• Unipolar- : assign this setting to the output for an actuator which can decrease the
measured value.
• Bipolar : select this setting if you want to output the manipulated variable via one
current output only (split range).
• (8) Configure the outputs and switch on the controller.