Make trend history accessible through OPC HDA

Use the built-in OPC HDA server to make historical data generated by Trend worksheets accessible to other computers.

Note: This feature is not supported in projects that are configured to run on the Embedded target platform. For more information, see About target platforms, product types, and target systems.

The OPC Historical Data Access (OPC HDA) specification is used to exchange archived process data, such as the historical data generated by Trend worksheets in your project. This is in contrast to other OPC specifications — for example, OPC DA (also known as OPC Classic) and OPC UA — that are used to exchange real-time data.

The project runtime software for Windows includes a built-in OPC HDA server that you can use to make your project's trend history accessible to OPC HDA clients. The server only works with trend history that has been saved in the Proprietary format, as opposed to the Database and Historian formats. When the server is enabled, it automatically scans the project folder for all saved history files (.hst) and then makes the contents of those files accessible.

There are no user-configurable settings for the OPC HDA server itself, but to enable the server, you must ensure the OPC HDA Server task is started during project run time. You can configure the task to start automatically when the project is run, or you can manually start the task after the project is running. For more information, see Runtime Tasks.

Once your project is running and the task is started, you should be able to use any compatible OPC HDA client program to access the historical data. The OPC HDA server address is the same as your project's data server address, its port number is 135 (DCOM), and it should appear to the client as "Studio.Scada.HDA.OPC".

This feature only supports the 1.0 version of the OPC HDA specification.