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Incorrect determination of the type of OPC tag


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Hello,

Could you please share your thoughts about problem shown below?

 

Thanks in advance.

 

Software used:

LabVIEW 2013 f2, 32 bit

DSC 2013

 

Problem:

 

When trying to read a value of tag from third party OPC server which is not widespread software using NI DSC OPC client we got empty data.

The type of tag in OPC server is Array of U16 and OPC server continuously writes array of values into that tag. However, NI DSC OPC client (and Distributed Systems Manager as well) defines type of that tag as String, thus can not read value of that tag (I suppose that NI OPC client is trying to treat variant data which holds array of U16 as string and because of conversation error issues empty data).

At the same time Kepware’s OPC client defines type of that tag as a String as well, but can read the values of that tag which holds Array of U16 (I suppose that Kepware’s OPC client after getting error, while converting Array of U16 into String, starts to look in datatype defined into variant itself).

 

Questions:

  • Can the descriptions above explain the problem and if yes then what can we do to read the value of tag with DSC?
  • Is there any opportunity to get more deep access to NI DSC OPC client to make some changes in order to work with customer OPC Server?
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