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SC-F70
SC-F70
PID Operation Operating Instructions
Procedure-2 Setting the PID Constants with Auto-Tuning
The controller computes the optimal control output value from the
difference between the target set value and the measured value for
automatic operation. To obtain proper control output, you must provide the
controller proper PID constants.
You can use the following two ways to obtain the proper P, I, and D
constants.
1. Study the individual characteristics of your control process equipment
yourself and generate the proper constants.
2. Run the Auto-tuning operation on the controller. The controller calculates
the data based on the characteristics of the process to get the optimal PID
constants for the process.
Notice for Running Auto-Tuning
The auto-tuning operation requires temporary On and Off actions
during its process. Due to the On-Off actions, the measured value
(and the control output) oscillates above and below the target set
value. Therefore, if the measured value is higher than the target set
value or the oscillation impedes your production, you must either
lower the target set value or do a manual PID setting by referring to
"PID Constants Manual Tuning Method" on page 103.
In some cases, the optimum PID constants may not be obtainable
through the Auto-tuning operation.
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