Forcing a Variable

At run-time, double-click on the value of the variable in the list or press the ENTER key when it is selected. A popup window appears and allows you to:

  • Force: Change the value of the selected variable.
    • Depending on the variable type, you have the possibility to define its value either in the text field or with the check boxes.

      Forcing a Variable

    • Figure 1: Forcing a Variable

    The variable locking feature can be enabled or disabled via the PLC Options device toolbar button. If enabled, the Lock and Unlock buttons are accessible:

    If disabled (default), the Lock and Unlock buttons are not accessible:


    • If PLC variable locking is enabled, the controller Runtime requires an additional 3% to 10% CPU processing power to manage the PLC variable locking. For the best controller performance, disable PLC variable locking.

  • Lock: When a variable is locked, its value is no longer changed by the runtime.
    • You can then force its value from the debugger, independently from the runtime operations.
    • All variables can be locked and forced at run-time.

  • The value of a locked variable is displayed with square brackets.

  • Unlock: Remove the lock on a variable so it can be changed again by the runtime.