Mitsubishi Electronics Q64TCTTBWN Network Card User Manual


 
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4.6 Auto Tuning Function
This function is designed for the Q64TCN to set the optimum PID constants automatically. In auto tuning, the PID
constants are calculated according to the hunting cycle and amplitude generated by repeated overshoot and
undershoot of the process value (PV) against the set value (SV) due to the on-off action of control output.
(1) Auto tuning operation
The Q64TCN operates as follows.
Remark
The time takes for auto tuning depends on the control subject.
Operation of the Q64TCN
1 Starts auto-tuning
2
Collects data from the point when the temperature process value (PV) reaches the set value (SV) after the first
overshoot and undershoot
3
After data collection, auto tuning ends when PID constants and loop disconnection detection judgment time are
set.
Common
Set value (SV)
(Temperature process value (PV))
Time
Temperature process
value (PV)
1 Start of auto tuning
2 Data collection
Auto tuning in execution
3 End of auto tuning
ON
OFF
ON
OFF
The first overshoot and
undershoot are ignored.
Temperature
control
CH Auto tuning instruction
(Yn4 to Yn7)
CH Auto tuning status
(Xn4 to Xn7)
Executed in a sequence program
Executed by the Q64TCN