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4-1
Fuzzy Self-tuning Operation
The fuzzy self-tuning function has three features, step response tuning (SRT),
disturbance tuning (DT), and hunting tuning (HT).
4-1-1 Step Response Tuning (SRT)
SRT is used to obtain all PID constants using a step response method when the
Temperature Controller starts operations.
SRT is also used when the set point changes value exceeding a set range while
the Temperature Controller is operating. After SRT has been executed, no SRT
will be executed the next time the Temperature Controller starts operating, un-
less the set point has been changed.
Set point
Max. tempera-
ture slope R
Tuning at startup
Dead time L
In step response tuning, control is completely imposed step-
wise to measure the maximum temperature slope (R) and
dead time (L), and the most ideal PID constants for the de-
vice are obtained from R and L.
Output (%)
100% imposed
step-wise control
amount.
Advanced PID
P X 1.27
100
Note Be sure to turn on the power supply to the load either before or simultaneously
with the start of Temperature Controller operation. When using the E5AJ-A2HB
or E5EJ-A2HB, you can change the RUN/STOP setting to RUN via event input
2 after supplying power to the load.
Dead time will be measured from the time the Temperature Controller starts
operating. If a load such as a heater is turned on after the Temperature Control-
ler is turned on, dead time longer than the actual value will be measured and
inappropriate PID constants will be obtained. If an extremely large amount of
dead time is measured, the control amount will be set to 0% for a short period of
time before being returned to 100%, and the constants will then be retuned.
Retuning is performed only for large amounts of dead time, so be sure to follow
the precaution given above when starting operation.
Fuzzy Self-tuning Operation
Section 4-1
