What are internal datapoints?

Internal datapoints are an essential part of WinCC OA. In internal datapoints basic information of the systemstate, system/managersetting are stored. Such information are the connected manager to the event-manager, the connection state of drivers, the redandancy active-passive state, the name of the actually opened panel in an User interface Manager with a certain manager number, the system user setting, authorization levels and passwords, configurationsetting for historical database or for alarm- and Eventscreen...

By sending internal datapoints basic system actions are triggered. Such actions are the loading of modules, panels and panel layers in User interface Manager, the active-passive redandancy switch, the triggering of general or single queries in the drivers, the setting and the change of file sets in the historical Data base.

As name convention in WinCC OA all internal datapointtypes and datapoint use underline "_" as first character.
The internal datapoints are normally parameterized via appropriate parameterization panels, for example parameterization panel for historical database, drivers ...

In the WinCC OA OnlineHelp, in chapter "Reference tables --> Internal datapoint types" a list of important internal datapointtypes, their sturcture and description is available.