_default (Default value)

A default value can in exceptional situations become the valid online value of a data point element and, as such, is always valid. Thus, it must be within the WinCC OA value range of the data point element. A valid value can be defined explicitly as a default value by the user, Control, API or automatically by WinCC OA. The defined default value is only used if the configured conditions are true.

The Configuration panel allows you to assign default values to data point elements under certain conditions. This is done with attributes from the _default config. Double-click on the config to open the Default value panel.

The appropriate data point attributes can be found in the Appendix.

Figure 1. Default value panel

Default value panel

The name (and description or alias) of the data point element to be edited is displayed in the combo box on the panel.

Default value

Enter the desired value in the Default value input box. However, always make sure that data point element and default value data types match. In the check boxes click to specify the conditions under which you want to set the default value:

  • If original value is invalid explicitly or set to invalid by the driver - the default value is set by the status bit "original value is invalid".

  • If WinCC OA value range is violated - the default value is set by the status bit "WinCC OA value range violation".