3.8 Adjusting Control Operation
E5EK
3--25
•
AT (auto-tuning) cannot be executed while operation is reset or dur-
ing ON/OFF control.
•
When you execute auto-tuning, the optimum PID parameters are au-
tomatically set by forcibly changing the manipulated variable to cal-
culate the characteristics (called the “limit cycle method”) of the con-
trol target. During auto-tuning, time counting is stopped and the
“AT” LED flashes.
•
40%AT or 100%AT can be selected by the limit cycle of MV change
width. Specify [
] or [
], respectively, in the “AT execute/
cancel” parameter (level 1 mode).
•
During heating and cooling control on a standard type controller, and
on a position-proportional type controller, only 100%AT can be
executed. (So, “
: 40%AT” is not displayed.)
•
To cancel AT execution, specify “
: AT cancel”.
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 wheth-
er or not the deviation (DV) at the start of AT execution is 10% full-scale
or less.
Deviation at start of AT
execution
≧
10% FS
Deviation at start of AT
execution < 10% full-scale
Limit cycle of MV change
width 40%
Limit cycle of MV change
width 40%
Set point
Set point
Start of AT
execution
End of AT
execution
Start of AT
execution
End of AT
execution
Time
Time
Deviation 10%
full-scale
Deviation 10%
full-scale
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 fluc-
tuations in the process value.
Set point
Start of AT
execution
End of AT
execution
Time
Limit cycle of MV
change width 100%
J
Auto-tuning
(A.T.)
F
40%AT
F
100%AT
Summary of Contents for E5EK
Page 1: ...User s Manual Cat No H089 E1 02 Digital Controller Programmable Type...
Page 24: ...CHAPTER 1 INTRODUCTION 1 14...
Page 36: ...CHAPTER 2 PREPARATIONS 2 12...
Page 162: ...CHAPTER 6 USING THE COMMUNICATIONS FUNCTION 6 20...
Page 176: ...CHAPTER 7 CALIBRATION 7 14...
Page 193: ...SETTING LIST A 11...