DCS System OPC server communication with C#


first time posting questions here. So I am trying to communicate using C# with the OPC server provided by Control Builder F. The server has automation interface 1.0 implemented and the problem i am having is that my program can connect to the server and retrive data alright. however aftet around 6 hours the opc server always crashes with an error of 800700A4. no more threads can be created within the system.

any help would be greatly appreaciated. thanks

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asked 7 months ago



Have you googled that error it looks like it's a general Windows message. And if I read it correctly you should check that your program correctly open and closes your functions as it the error points to a memory leak.


answered 7 months ago


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Looks like a recource leak. This happens for example if you register new tags for transfers between the OPC-Server and your C# program, and not unregister after you're done. C# (or java) programmers tends to forgot to free external recources after use, because internal recources are freeed automaticly by the runtime environment.

- unregister all subscription who are not needed anymore

- unregister all tags who are not needed anymore

- unregister (or re-use) all groups who are not needed anymore

- close (or re-use) all connection instances to the opc-server after not needed anymore.


answered 7 months ago


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