WIKA CS4R - Manual (Page 22)

Operating Instructions Temperature Indicating Controller CS4R
V1.2 • 05/2006 - 22 -
9. PID auto-tuning of the CS4R
In order to decide each P, I, D and ARW value automatically, this system gives a fluctuation to the controlled
object to get an optimal value. 1 of 3 types of fluctuation below is automatically selected.
[When the difference between the setting value and processing temperature is large as the
temperature rises]
When AT bias is set to 20°C (°F), fluctuation is applied at the temperature 20°C (°F) lower than the setting
value.
Temperature 20°C (°F) lower than the setting value
(1) Calculating PID constant
(2) PID constant calculated
(3) Controlled by the PID
constant set by auto-tuning.
(4) AT bias value
[When control is stable]
Fluctuation is applied at the setting value.
(1) Calculating PID constant
(2) PID constant calculated
(3) Controlled by the PID
constant set by auto-tuning
[When the difference between the setting value and processing temperature is large as the
temperature falls]
When AT bias is set to 20°C (°F), fluctuation is applied at the temperature 20°C (°F) higher than the setting
value.
Temperature 20°C (°F) higher than the setting value
(1) Calculating PID constant
(2) PID constant calculated
(3) Controlled by the PID
constant set by auto-tuning.
(4) AT bias value
(1) (2) (3)
(4)
AT starting point
Setting
value
Temperature
Time
AT starting point
(1) (2) (3)
Temperature
Setting
value
Time
AT starting point
(1) (2) (3)
(4)
Temperature
Setting
value
Time