Please ensure Javascript is enabled for purposes of website accessibility
Powered by Zoomin Software. For more details please contactZoomin

AVEVA Enterprise SCADA

TABLE OF CONTENTS

Client browsing

Save PDF
Save selected topicSave selected topic and subtopicsSave all topics
Share
Share to emailCopy topic URL
  • Last UpdatedApr 24, 2025
  • 2 minute read

The client browser sees all RealTime database (RTDB) records that can be accessed by the client. Since many Open Platform Communications (OPC) browsing clients do not handle large amounts of data well, be careful when browsing the RTDB.

A default configuration of the OPC server supports browsing of the entire RTDB, not just records that have clients with current attachments or records that have been loaded into the OPC server’s cache. The client browser sees all RTDB records that are capable of being accessed by the client.

When an instance of the OPC Server uses an allowlist, it will affect the client's ability to browse the RTDB. As opposed to the default configuration, an OPC client will only be able to see the points that are allowlisted in the browser. The figure below demonstrates the effect that an allowlist has on browsing.

The allowlist that was used by the OPC Server in the above figure contained only three points: 0analog, 0rate, and 1 from the Remconnjoin table. There were other rate, analog, and remconnjoin records in the tables, but they do not show up in the browser because the allowlist has been applied. The RTDB that was accessed by this example’s allowlisted OPC Server instance also contained status records. The allowlist prevented the status records from appearing in the browser. Any allowlist is applied to the OPC Server at startup or upon restart, and will affect the client's ability to browse the RTDB.

Although client browsing is useful for the configuration of small applications, you should be careful when attempting to browse the RTDB. Many OPC browsing clients do not handle large amounts of data very well. Some projects have telemetered tables containing thousands of records. Expanding a table with this many records in the browser, can cause a timeout or delay for the browser. It is best to enter the paths for records in these situations, rather than browsing to the point.

Note: If your client has a browse all option, you must ensure that this option is turned off prior to connecting to the AVEVA OPC server.