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Entry type: FAQ Entry ID: 9126125, Entry date: 10/06/2005

What options do I have for accessing an OPC server via an office network?

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Configuration Notes:
There are two possible options for making a remote connection from an OPC client:

  1. Remote connect via DCOM configuration

    An OPC server can be accessed via a connect call from the OPC client application. If this application is located on a PC other than the server PC, the connect call has to be redirected by several parameters in the registry. The requisite parameters are set by the Windows tool "dcomcnfg.exe". The requirement for this is the "OPC client installation" from the SIMATIC NET CD! You can find further information about the DCOM configuration in the manual "Commissioning PC Stations" under "Start > Simatic > SIMATIC NET ".

    Fig. 01
  2. Remote connect via connect with optional "node name" parameters
    Remote connect to an OPC server from another computer is possible by extending the "Connect" call during access via the automation interface (e.g. Excel VBA, VisualBasic). In this case, the name of the server PC must be entered as the optional "node name".
    The user registered on the client PC must be authorized to start the OPC server on the server PC.

    Example (local):

    Set MyOPCServer = New OPCServer
    Call MyOPCServer.Connect ("OPC.SimaticNet")

    Example (remote):

    Set MyOPCServer = New OPCServer
    Call MyOPCServer.Connect ("OPC.SimaticNet", "Nodename")

    Fig. 02

If you wish to use the likes of Excel or VBA on the client PC or to develop your client directly there, you have to install SIMATIC NET PC software in either case. There is no need to configure the client PC any further.

When SIMATIC NET software is installed on the client PCs, there is no need for any further SIMATIC NET software license.

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