Auto-Tuning - Omron E5AK User Manual

CHAPTER 3 BASIC OPERATION
J Auto-tuning
(A.T.)
F 40%AT
Deviation at start of AT
execution ≧ 10% full-scale
Set point
Start of AT
execution
F 100%AT
3--16
• AT (auto-tuning) cannot be executed while operation is canceled or
during ON/OFF control.
• When you execute auto-tuning, the optimum PID parameters 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 [
cancel" parameter (level 1 mode).
• During heating and cooling control and with position-proportional
type, only 100%AT can be executed. (So, [
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 to execute
compared with 100%AT.
The timing by which limit cycles are generated varies according to
whether 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 fluctua-
tions in the process value.
Set point
Start of AT
execution
] or [ ], respectively, in the "AT execute/
] ("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
] (40%AT) will not be
Limit cycle of MV change
width 40%
Time
End of AT
Time