Third-Party OPC Client - System Connections

You can use a third-party OPC client application to access your Geo SCADA Expert system. To do this, you need to install the Data Access components of Geo SCADA Expert on the same PC as the third-party OPC client application. You will also need to configure the third-party application so that it can make a connection to the Data Access components (as the Data Access components handle the communications to the Geo SCADA Expert server).

Communications between the Geo SCADA Expert server and the Data Access components installed on the OPC client work in exactly the same way as communications between a ViewX client and Geo SCADA Expert server—there is one link that is used for client to server messages and server responses and a server advise link for unsolicited messages from the server. For more information, Understanding Client - System and Server Advise Connections.

To allow a third-party OPC client to access the Geo SCADA Expert system, the Data Access components have to be:

• Installed on the third-party OPC client PC
• Able to access a valid connection to Geo SCADA Expert on the OPC client PC
• Associated with a valid OPC license.

To connect a third-party OPC client to the server:

1. Check that the Geo SCADA Expert Client connections are configured correctly (see Configure the Third-Party OPC Client - System Connection). A full ViewX license is not required - an OPC Client license can be used to provide an OPC only connection.
2. Check that you have a valid OPC Client license by examining the License Details display (right-click on the server icon in the Windows taskbar then select the License Details option). The license limit comprises that shown for OPC Clients in the 'Limits' section of the License Details window. For more information, see Display the License Details Window on a Geo SCADA Expert Server.