Omron E5EK - MANUAL 2 User Manual page 44

+ Auto-tuning
(A.T.)
' 40%AT
Deviation at start of AT
execution y 10% full-scale
Set point
Start of AT
execution
' 100%AT
AT (auto tuning) cannot be executed while operation is canceled or dur
ing ON/OFF control.
When you execute auto tuning, the optimum PID parameters for the
current set point at execution are automatically set by forcibly changing
the manipulated variable to calculate the characteristics (called the
limit cycle method") of the control target. During auto tuning, the AT
LED flashes.
40%AT or 100%AT can be selected by the limit cycle of MV change width.
Specify [ ] or [
rameter (level 1 mode).
During heating and cooling control, only 100%AT can be executed. (So,
[ ] (40%AT) will not be displayed.)
To cancel AT execution, specify [
In order to set the limit cycle of MV change width to 40%, select 40%AT
to execute auto tuning with fluctuations in the process value kept to a
minimum. However, note that auto tuning takes longer time to execute
compared with 100%AT.
The timing by which limit cycles are generated varies according to wheth
er or not the deviation (DV) at the start of AT execution is 10% full scale
or less.
Limit cycle of MV change
width 40%
Deviation 10%
full-scale
Time
End of AT
In order to set the limit cycle of MV change width to 100%, select 100% AT
to shorten the AT execution time without worrying about fluctuations in
the process value.
Set point
Start of AT
execution
3.7 Adjusting Control Operation
], respectively, in the "AT execute/cancel" pa
] (AT cancel").
Deviation at start of AT
execution < 10% full-scale
Set point
Deviation 10%
full-scale
Start of AT
execution
Limit cycle of MV
change width 100%
End of AT
Limit cycle of MV change
width 40%
Time
End of AT
Time
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