PAI status and commands

Use the
General
 tab on the
PAI Properties
 dialog box to monitor the instruction status, issue online commands, and set parameter values for Process Analog Input (PAI) instructions.
To monitor status and issue online commands for PAI instructions
  1. On the instruction in the routine, perform one of these actions:
    • On the Ladder or FBD instruction, select .
    • In the Structured Text editor, right-click the tag name and select
      Configure <tag name>
      .
  2. Configure these settings:
    • Scaling
      . Select a method for scaling the Input PV in raw units to engineering units.
      • No scaling
      • Linear scaling
      • Square root scaling.
        Use the
        Advanced
         tab to check or set the max and min limits used in scaling.
    • PV clamping limits
      ,
      high
      and
      low
      . Enter the high and low clamping limits. Use this numerical entry to check or set the high and low limit value for clamping PV.
      Use the
      PV units
       box on the
      HMI
      tab to label the engineering units.
    • Replace PV value
      . Enter the PV value to use when the PAI instruction is configured to
      Replace PV value
       if the PV quality is not guaranteed. Use the
      HMI tab
       to enter the unit label for PV units.
    • Device: Virtual
      . When in Maintenance mode, select to switch to Virtual operation.
    • Device: Physical
      . When in Maintenance mode, select to switch to Physical operation.
    • Virtual PV value
      . Enter the PV value the instruction uses when the device is in Virtual mode.
    • Maintenance substitution
      . Changes the PV source when the device providing the PV value is in maintenance mode. The button indicates the alternative PV source.
      • When
        Use substitute PV
         is displayed, select the button to use the substitute PV value in calculations.
      • When
        Use input PV
         is displayed, select the button to use the input, replace, or virtual PV value in calculations depending on the status of the PAI instruction. The selection is applied immediately.
    • Substitute PV value
      . Enter the PV value to use when the input device is in maintenance mode and the owner of the instruction is Maintenance.
    • Filter order
      . Select the filter to use for smoothing the PV value. The menu lists low-pass filter orders:
      • None
        , which passes through the PV value
      • 1st order filter
      • 2nd order filter
    • Cutoff frequency
      . Enter the Cutoff frequency (radians/second) to specify and apply filter characteristics to 1st order and 2nd order filter types. The cutoff frequency is the frequency above which the PV value is attenuated.
    • Clear capture
      . Clears the captured minimum and maximum PV values. After clearing the captured values, the PAI instruction continues capturing min and max PV values. The action is immediate if the command request does not need to be confirmed by the operator. If the command request requires a signature, this will enforce security from the HMI and disable commands and settings from the Logix Designer dialog.
    • Reference
      . Enter a reference PV value for calculating PV deviation.
  3. When online with the controller, monitor the
    Device state
     and
    Device issues
     indicators at the bottom left of the dialog box:
    • Device state
      . Displays the current device state, such as
      PV good
       or
      PV uncertain
      .
    • Device issues
      . Displays fault conditions, such as
      PV bad
       or
      Configuration error
      .
  4. Select
    Apply
    .
Provide Feedback
Have questions or feedback about this documentation? Please submit your feedback here.
Normal