OPC Status Information

The Server Status Tool provides status information that is organized into groups of categories, each of which contains sub-categories. One of these groups is named OPC.

The OPC group provides status information about the OPC tags that are being used by clients connected to the server. For example, a client that is displaying a Mimic with ‘live’ values will reference an OPC tag for each value. Information about each of those tags is shown in the OPC group on the Server Status Tool (on the server to which the client is connected).

The OPC group contains the following sub-categories:

• .NET Tags—Reserved for use with future client applications.
• DA Groups—provides status information about the DA Groups to which a client subscribes.
• DA Items—provides status information about the OPC DA tags to which the OPC DA client(s) is subscribed.
• HDA Items—provides status information about the historic HDA tags to which the OPC DA client(s) is subscribed.
• XML-DA Items—provides status information about any XML-DA tags to which the OPC DA client(s) is subscribed.
• XML-DA Subscriptions—provides status information about XML-DA subscriptions. This information is often useful when determining whether Original WebX clients are being updated at a suitable rate.