Azbil SLPC1F, Руководство пользователя

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5-26
Chapter 5. Adjusting PID Values
„
Step 3: Start data sampling
Once the PV and MV are stable, select [Trend monitor]
→
[Trend Monitor Start
(T)]
from the Trend Monitor menu or click on the toolbar to start sampling
data.
After data sampling is started, collect 10 or more data items (for 10 seconds if the
sampling cycle is 1 second) in a state in which the PV and MV are stable, as shown
in the figure below.
10 or more stable data items
Magnified view
Note
•
If the PV and MV are stable in MANUAL mode, set the set point of the controller
to the same value as the current stable PV (if the current PV is 60.5 °C, set the
controller set point to 60.5) while sampling stable data. If necessary, change the
PID values as well. These operations are performed in Step 4, but doing them in
this step can reduce the number of operations in Step 4.
„ Step 4: Start step response
Start step response after sampling 10 or more data items of the stable PV and MV.
The method for starting step response differs depending on the current mode.
z In AUTO mode
(1) Change the PID values if necessary. This operation may make the PV or MV
unstable; however, continue the operation.
(2) Change the set point of the controller to the step response set point.
z In MANUAL mode
(1) Change the PID values if necessary
(it is not necessary if it was already done in Step 3).
(2) Change the set point of the controller to the same value as the current PV. For
example, if the current PV is 60.5 °C, change the set point of the controller to 60.5.
(it is not necessary if it was already done in Step 3).