Last published value is "null, Uncertain_InitialValue..." in the tag Editor

Ignition Designer:


Ignition gateway:


The ignition gateway can read the data from the opc server , but tag browser show null value in the first picture?

Presumably this means KSE hasn't sent a PublishResponse containing values for those tags yet for some reason. In the QC you're just doing a read, not a subscribe, so it's different.

It doesn't look like anything is wrong with your Ignition configuration, so it might be a Kepware issue. If you can turn off security for the connection and get a Wireshark capture we can verify that the Subscription and Monitored Items get created but no values are received.

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The IP address of the opc server is 192.168.150.23 and the ignition gateway is 192.168.150.4

A screenshot is not sufficient. Please post the actual PCAP file, or send it to IA support.

We'll need the PCAP file.

Make sure you start the capture and then edit/save the connection once you are recording so that the Subscription and Monitored Item creation is captured.

pacp.rar (2.4 MB)

The file size is too big, so I had compress it. 7Z or WinRAR can uncompress it.

This capture only contains traffic for an existing connection, not a new one that includes subscription and item creation by edit/saving in Ignition.

It doesn't contain any PublishResponses with data change notifications, but that doesn't mean anything because they aren't immediately following the subscription and items being created.

there was a login error : IllegalArgumentException: Cannot create PyString with non-byte value

It is not work after restart the vision module in gateway