Mitsubishi Electronics MELSEC-F Manuel D’Utilisation
M-18
4 Auto-Tuning
FX
3G
/FX
3U
/FX
3UC
PLC User's Manual - Analog Control Edition
PID Instruction (FNC 88)
4.1 Limit Cycle Method
4. Auto-Tuning
This chapter describes the auto-tuning function of PID instruction.
The auto-tuning function will automatically set the important constants, such as the proportional gain and the
integral time, to ensure optimum PID control.
There are two auto-tuning methods: limit cycle method and step response method.
The auto-tuning function will automatically set the important constants, such as the proportional gain and the
integral time, to ensure optimum PID control.
There are two auto-tuning methods: limit cycle method and step response method.
4.1
Limit Cycle Method
4.1.1
Parameters set in auto-tuning (of limit cycle method)
Parameter
Setting position
Proportional gain (K
P
)
+3
Integral time (T
I
)
+4
Differential time (T
D
)
+6
S
3
S
3
S
3
S
3
S
3