Hi Daniau, <a href="http://zone.ni.com/devzone/conceptd.nsf/webmain/DF8C0A4BA2E2B22A86256A3700592BEA?opendocument";>Here</a> is a tutorial that explains how to connect LabVIEW to an OPC Server via DataSocket.
It is odd to hear about this type of behavior in LabVIEW, where the first unit of data is correct, but everything after that appears "truncated" or "rounded". Since your initial data is displayed correctly, I would go as far to say that the connection between the OPC Server and LabVIEW should be fine. However, to ensure that this problem is related to receiving data in LabVIEW and not in the computer, I would try to monitor this data using any other available software on the development (LabVIEW) computer just to make sure it is the reading application and not the source. Also, based on your description of your While Loop, it may be worthwhile to try a slight modification. Remove your Variant to Data VI, and take your Double (DBL) constant and wire it into the Read DS 'type' parameter. This is essentially the same thing as you had before, but it may resolve the "truncating" issue. Hope this helps. Let me know if you need any more help, and I will be more than happy to assist you further. Good Luck! Jeremy L. National Instruments
