Setting the OPC Server

The first step is to configure the related OPC server appropriately consistent with the existing base automation or with the used connection. This software is normally provided by the producer of the controller (for example Siemens, Schneider, Allen Bradley, ...) or by the producer of the communication card for the PC (for example Comsoft, Hilscher, Siemens, ...). Proceed as described in the instruction provided by the producer to configure the server or when necessary also to configure the hardware.

In the following description, the connection to Schneider OFS 2.5 OPC-Server will be described. This allows the connection to controllers of thePremium, Premium TSX and Quantum family using different protocols (XIP, ModbusTCP, Unitelway,....). The server merely serves as an example and does not present any preference compared to other producers. The correct configuration of the server is not part of this document.

Almost each OPC server producer also provides a unique OPC Test Client. Often it is advisable to verify the communication with the periphery through this test client - this way you can detect hardware problems or configuration errors on the underlying level clearly. Thereby, the process is the same as described later - the basic steps are 1) Start the client, 2) Select the server, 3) Create new group, 4) Create new item and 5) Assign producer/bus specific address to the item. Subsequently, you can already monitor the value changes from the periphery (value changes, updated time stamp, quality = GOOD).

An OPC server can run either locally on the same computer as the SCADA system (recommended) or remote on another computer. If it should be necessary to embed a remote running OPC server, there are two possibilities: a) The use of an automatic remote connection through DCOM (not recommended) or b) To run the WinCC OA OPC Client also on a remote computer. The second option uses the secure WinCC OA communication for the connection with the SCADA system.