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OPC UA Node Addressing - DataValue Attribute Type?

I have set up an OPC UA Client in VTScada. I am trying to access data along with its timestamp. Does VTScada support all the different types as defined in part 6 of the OPC Foundation’s OPC UA specification, section 5.1.2? I am looking to use the DataValue type (23).

I have created two tags with the same node addressing but one has the ty field set to 1, and the other 23. The value for both tags is only the data. The tag with ty=23 does not have any other information when viewing in the tag browser.

When I use UA Expert as a client I can see all of the value attributes including Source and Server Timestamp, along with the data. Is this something VTScada supports?

I have set up an OPC UA Client in VTScada. I am trying to access data along with its timestamp. Does VTScada support all the different types as defined in part 6 of the OPC Foundation’s OPC UA specification, section 5.1.2? I am looking to use the DataValue type (23). I have created two tags with the same node addressing but one has the ty field set to 1, and the other 23. The value for both tags is only the data. The tag with ty=23 does not have any other information when viewing in the tag browser. When I use UA Expert as a client I can see all of the value attributes including Source and Server Timestamp, along with the data. Is this something VTScada supports?
edited 4 days ago at 6:45 pm

I reached out to our dev team for more on this and they confirmed the following:

"
VTScada supports the DataValue type (pt 6, 5.2.2.17). It sets up MonitoredItems in the OPC UA server to return both the source timestamp and server timestamp. When storing data retrieved from the OP CUA server, VTScada prefers to use the source timestamp, if available, otherwise the server timestamp. The timestamp and data is stored in the IO tag and used when recording data for the VTScada Historian.
"

Therefore, you won't see the timestamp in the tag but, if you look at the data's raw view, you should see the timestamps associated with value changes are based on the source timestamp and not the server's received timestamp.

If this isn't working for you, you may want to set your server to UTC time just to check to see if there is a timezone issue affecting your results. Just a thought.

If you are looking to do something like draw a timestamp from a tags most recent value, you can always create a calculation tag where the expression is set to [TagYouNeedTimeStampFor]\Timestamp. I suspect this calculation tag would need to be a string but am unsure if the result will be given as a timecode or string value. If a timecode is returned, you may need to add some extra functions to the expression to convert the timecode to a readable timestamp in the format you wish to show.

I reached out to our dev team for more on this and they confirmed the following: " VTScada supports the DataValue type (pt 6, 5.2.2.17). It sets up MonitoredItems in the OPC UA server to return both the source timestamp and server timestamp. When storing data retrieved from the OP CUA server, VTScada prefers to use the source timestamp, if available, otherwise the server timestamp. The timestamp and data is stored in the IO tag and used when recording data for the VTScada Historian. " Therefore, you won't see the timestamp in the tag but, if you look at the data's raw view, you should see the timestamps associated with value changes are based on the source timestamp and not the server's received timestamp. If this isn't working for you, you may want to set your server to UTC time just to check to see if there is a timezone issue affecting your results. Just a thought. If you are looking to do something like draw a timestamp from a tags most recent value, you can always create a calculation tag where the expression is set to [TagYouNeedTimeStampFor]\Timestamp. I suspect this calculation tag would need to be a string but am unsure if the result will be given as a timecode or string value. If a timecode is returned, you may need to add some extra functions to the expression to convert the timecode to a readable timestamp in the format you wish to show.

Trihedral Engineering Ltd.

edited 4 days ago at 5:24 pm
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