Mitsubishi FX3U-4AD User Manual page 451

FX /FX /FX PLC User's Manual - Analog Control Edition
3G 3U 3UC
PID Instruction (FNC 88)
4.1.2 Auto-tuning procedure
1
Set the forward or backward operation
Set the operation direction flag (bit 0) in the operation setting parameter (ACT)
2
Select the auto-tuning method (limit cycle method)
Set the auto-tuning method to ON (bit 6) in the operation setting parameter (ACT)
(When bit 6 is set to OFF, the step response method is selected.)
3
Set the auto-tuning execution flag to ON
Set the auto-tuning execution flag to ON (bit 4) in the operation setting parameter (ACT)
4
Set the input filter
Set the input filter in the operation setting parameter (ACT)
5
Set the sampling time
Set the sampling time
6
Set the Upper Limit Value (ULV)
Set the Upper Limit Value (ULV) of the output value (MV) in the operation setting parameter (ACT)
+26.
S S
3 3
7
Set the Lower Limit Value (LLV)
Set the Lower Limit Value (LLV) of the output value (MV) in the operation setting parameter (ACT)
+27.
S S
3 3
8
Set the threshold (hysteresis) (SH
Set the threshold (hysteresis) width (SH
9
Set the target value (SV)
Set the target value (SV) to
10
Set the ON PID instruction command input to start auto-tuning
Auto-tuning is executed according to the measured value (PV).
When auto-tuning is completed, the auto-tuning flag (bit 4 and bit 6) turns OFF in the operation set-
ting parameter (ACT)
.
S S
3 3
)
PV
) in the operation setting parameter (ACT)
PV
in PID instruction.
S
1
+1.
S S
3 3
+2.
S S
3 3
↓
4 Auto-Tuning
4.1 Limit Cycle Method
K
+1.
S
3
L
+1.
S S
3 3
+1.
S S
3 3
+25.
S S
3 3
L-19