Allen-Bradley 2080-LC20-20AWB, Руководство пользователя

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Rockwell Automation Publication 2080-UM005E-EN-E - March 2018
Appendix D PID Function Blocks
PID Function Block
This function block diagram shows the arguments in the PID function block.
The following table explains the arguments used in this function block.
Auto – TRUE = Normal operation of PID.
FALSE = Output tracks Feedback.
Feedback Feedback of the control being applied to the
process. Usually it’s the PID’s CV after any
limits or manual control has been applied.
AutoTune TRUE = Autotune.
FALSE = No Autotune.
ATParameters Autotune parameters
ATWarning Autotune warning
OutGains Gains from Autotune
Initialize Used for AutoTune
Comparison Between IPIDCONTROLLER and PID
IPIDCONTROLLER PID Description
PID Arguments
Parameter Parameter
Type
Data Type Description
Enable Input BOOL Enable instruction.
TRUE = Start execution with current input parameters.
FALSE = CV equals zero.
PV Input REAL Process Value. This value is typically read from an
analog input module.
The SI unit must be the same as Setpoint.
SP Input REAL The set point value for the process.
AutoManual Input BOOL Auto or manual mode selection:
TRUE = Normal operation of PID.
FALSE = Manual operation using CVManual.
CVManual Input REAL Control value input defined for manual mode
operation. The valid range for CVManual is:
CVMin < CVManual < CVMax
PID PID
PV
Active
CV
AbsoluteError SP
AutoManual
CVManual
CVMax
CVMin
Gains
Control
Error
Error ID
Llnit
Enable