Addressing

It doesn't matter where you want to access an individual element of a data point (such as P2) in WinCC OA, you can always do that device oriented by entering the complete element identifier. In PARA, the data point element name of the actual rotation speed is displayed in the field "DPE:" on the top right. (see also figure on the page Settings for a Data Point Element)

System1:P2.state.speed

System name:DatapointName.Element1.Element2. … ElementN

The systemname "System1" automatically exists in each new project. The system name could be changed if several WinCC OA systems should be combined to a "distributed system" (Multi Server Cluster). In this example, however, the name is not of importance.

When addressing local data point elements of the own system (like in this case), the system name can be omitted. Therefore the rotation speed could also be addressed like this:

P2.state.speed

For more information on the addressing of data points, see the chapters configs and CONTROL Programming as well as the chapter Addressing in the online help.

Each process variable can be addressed via two different addressing options in WinCC OA. One way is the addressing by the device oriented data point element identifier with the dot notation.

The second way is to use the ALIAS addressing. With the alias addressing you can additionally consider arbitrary plant identification systems. Unlike the DPE identifiers, the alias is not necessarily built hierarchically. For more information on the alias addressing, see chapter addressing of this online help.