Instructions
9.2 PID_3Step
PID control
Function Manual, 03/2017, A5E35300227-AC
359
PIDSelf-
Tune.TIR.CalculateTIR-
Params
BOOL FALSE The properties of the controlled system are saved during tuning. If
CalculateTIRParams = TRUE, the PID parameters are recalculat-
ed on the basis of these properties. The PID parameters are calcu-
lated using the method set in TuneRuleTIR. CalculateTIRParams
is set to FALSE following calculation.
PIDSelfTune.TIR.Tune-
RuleTIR
INT 0 Methods used to calculate parameters during fine tuning:
• TuneRuleTIR = 0: PID automatic
• TuneRuleTIR = 1: PID fast
• TuneRuleTIR = 2: PID slow
• TuneRuleTIR = 3: Ziegler-Nichols PID
• TuneRuleTIR = 4: Ziegler-Nichols PI
• TuneRuleTIR = 5: Ziegler-Nichols P
The TIR.State tag indicates the current phase of "fine tuning":
Retain.Mode INT 0 A change to the value of Retain.Mode initiates a switch to another
operating mode.
The following operating mode is enabled upon a change of Mode
to:
• Mode = 0: Inactive
• Mode = 1: Pretuning
• Mode = 2: Fine tuning
• Mode = 3: Automatic mode
• Mode = 4: Manual mode
• Mode = 5: Approach substitute output value
• Mode = 6: Transition time measurement
• Mode = 7: Error monitoring
• Mode = 8: Approach substitute output value with error monitor-
ing
Retain.CtrlParams.SetByUser BOOL FALSE If SetByUser = FALSE, the PID parameters are determined auto-
matically and PID_3Step operates with a dead zone at the output
value. The dead zone width is calculated during tuning on the
basis of the standard deviation of the output value and saved in
Retain.CtrlParams.OutputDeadBand.
If SetByUser = TRUE, the PID parameters are entered manually
and PID_3 Step operates without a dead zone at the output value.
Retain.CtrlParams.OutputDeadBand = 0.0
Retain.CtrlParams.Gain REAL 1.0 Active proportional gain
Retain.CtrlParams.Ti REAL 20.0
• Ti > 0.0: Active integral action time
• Ti = 0.0: Integral action is deactivated