LSIS XBE-DC08A, User Manual

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Chapter 6 Built-in PID Function
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(b) If selecting auto-tuning, it shows the parameter setting window as seen in Figure 6.17.
<Figure 6.17 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 6.11 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.
(b) PWM output enable
PWM output means an output method to turn a junction on – off with a duty proportional to control output calculated by a
uniform output cycle. If PWM output is enabled, it realizes PWM output in accordance with PWM output cycle set in the
parameter of PWM output junction (P20 ~ P3F) designated in the parameter. At the moment, the PWM output cycle follows
the PWM output cycle separately set in auto-tuning operation cycle.