User manual

8.1.2 Selection of PID Tune and Operation Form
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TUNE SELECTION
By selecting one of the methods below, device can determine the PID
parameters.
Self tune (Step Response Tuning) operation
Device operates according to the defined PID
parameters
Auto tune (Limit Cycle Tuning) operation
Auto-Self Tune
Self Tune operation is performed, if the conditions are
realized when power on firstly. In normal operation, it
controls the tune conditions in Auto Tune
Auto Tune
selection which
explained below. If any of the conditions is realized, it
performs the operation.
Determining of PID parameters with is started in these conditions :
By the user in any time,
By the device when system gets unstable and starts oscillation
If process value is out of value (Please
refer to Section 8.2.2) and starts to oscillate, then device changes the
Parameter to andAuto Tune operation is started.
After changing set value, if difference between newly defined set value and
former set value is greater than proportional band, device will start it.
Auto Tune
1-
2-
Set ± Process value stabilisation
3-
There are 2 different methods for determining PID parameters by the device. These
are ( Limit Cycle Tuning) and (Step Response Tuning)
methods.
Auto tune Self Tune
ForAuto Tune ( Limit Cycle Tuning) operation
1- Auto
tune Auto-Self tune
2-
3-
:
Tune selection parameter in “run List” menu must be selected
or .
For being started Tune operation (Auto Tune or Self Tune) control form must be P,
PI, PD or PID.
If process set value is changed while Tune operation is being performed, Tune
operation is canceled
AUTOMATIC TUNE SELECTION
Device does not do (Limit Cycle Tuning) operation
or while operation runs, this selection is adjusted
and operation is canceled.Auto Tune
TUNE METHODS :
If parameter is or , when the
conditions for Auto Tune parameter that are explained in
Tune Methods section are realized, it starts to perform
Auto Tune (Limit Cycle Tuning) operation.
i
If set value is changed to a value that is greater than;
± [ Scale * ( Heating or Cooling Proportional Band) ] /1000 value,
Parameter is adjusted by the device and operation is
started.
Auto Tune