Hello.

Evaluation key sent by email.

Best regards

Thanks for the fast reply. 

currently we do not have a newer license. It would be great if you could provide an evaluation license. 

Hello.

The most likely cause of the error is indicated in the error message - QuickOPC has been performing operations to convert the data, it needed to access the server, and it took longer than expected. So this can be e.g. to some higher load on the server or on the network. Less likely, it can be client side issue (high load on the client computer, or some client-side bug including QuickOPC).

It is currently not possible to change the timeout value, but the current version has it increased to 10 seconds. And there were some other changes (such as referencing newer OPC UA stack), so first step I would recommend is to test with the newest QuickOPC version. If you do not have the license for the newest version and you need an evaluation license (free of charge) to remove the runtime limit of trial-version (30 minutes), let me know.

Best regards
 

We have an existing software application that connects to a PLC via OPC-UA-DA ( 5.70.1053). Recently, the error OpcLabs.UAEngine=451 has been reported occasionally.

The exact message is:
"OpcLabs.EasyOpc.UA.Engine.UAEngineException: Timed out waiting (2000 milliseconds) for a session to become available for a conversion."

 I was unable to determine the exact cause of this error.

What could be possible reasons for this error?
What can we do to fix it?
Is this an issue with the library itself, or is it a problem caused by how we are using it?
Would an upgrade to the latest version have any effects to this issue?