LSIS XBF-AD04A - Page 584

Chapter 15 PID Function (Built-in function)
15 - 35
(b) If selecting auto-tuning, it shows the parameter setting window as seen in Figure 15.17.
<Figure 15.17 Built-in auto-tuning function parameter setting window>
(c) Input items
Table shows the items to set in auto-tuning parameter window and the available scopes.
Items
Description
Scope
RUN direction
Set the run direction of auto-tuning.
Forward/reverse
PWM output enable
Set whether to set PWM output of MV enabled/
disabled.
Disable/enable
SV
Set SV.
-32,768 ~ 32,767
Operation time
Set auto-tuning operation time.
100 ~ 65535
Max. MV
Set the max. MV in control.
-32,768 ~ 32,767
Min. mV
Set the min. MV in control.
-32,768 ~ 32,767
PWM junction
designation
Designate the junction to which PWM output is
output.
P20 ~ P3F
PWM output cycle
Set the output cycle of PWM output.
100 ~ 65,535
Hysteresis setting
Set the hysteresis of auto-tuning MV.
0 ~ 65,535
< Table 15.11 Auto-tuning function parameter setting items>
(2) Description of auto-tuning parameters and how to set them
(a) RUN direction
RUN direction is to set the direction of auto-tuning run of a loop. The available option is forward
or reverse. The former (forward) means that PV increase when MV increases while the latter
(reverse) means PV decreases when MV increases. For instance, a heater is a kind of forward
direction system because PV (temperature) increases when output (heating) increases. A
refrigerator is a kind of reverse direction system in which PV (temperature) decreases when
output increases.