Mitsubishi Electric MELSEC-FX3S Series - Page 517

FX 3S /FX 3G /FX 3GC /FX 3U /FX 3UC PLC User's Manual - Analog Control Edition
PID Instruction (FNC 88)
M-19
4 Auto-Tuning
4.1 Limit Cycle Method
K
FX
3U
-4AD-PNK
-ADP
L
FX
3U
-4AD-TC
-ADP
M
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) +1.
2 Select the auto-tuning method (limit cycle method)
Set the auto-tuning method to ON (bit 6) in the operation setting parameter (ACT) +1.
(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) +1.
4 Set the input filter
Set the input filter in the operation setting parameter (ACT) +2.
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.
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.
8 Set the threshold (hysteresis) (SHPV)
Set the threshold (hysteresis) width (SHPV) in the operation setting parameter (ACT) +25.
9 Set the target value (SV)
Set the target value (SV) to in PID instruction.
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) +1.
S 3
S 3
S 3
S 3
S 3
S 3
S 3
S 3
S 1
S 3