M580 NUA0100 Module OPC Path

Ignition
1

Hey everyone,

Does anyone know of a way to alias the OPC Path browsed from a M580 NUA Module?

Right now the path is very long: EG

nsu=http://www.unifiedautomation.com/CustomServer/;s=0:TestTag

Does Ignition have a way to alias or is there a way to change this in the settings of the M580?

Thanks

2

You can't alias it in Ignition but you could probably parameterize a UDT or something...

Why are you concerned about it?

3

Functionally it works. It just seemed like a long path to me compared to how OPC-UA paths via Igniton's OPC-UA server are formatted.

4

Any tags from any server that come from a namespace at index 2 or above in the namespace table will use the namespace URI instead of namespace index.

Indices in the NodeId (OPC Item Path) are relative and some servers will change which tags belong to which namespace after a restart, so any index 2+ has to be explicitly specified so the client can resolve the proper index upon connecting. Index 0 and 1 have special treatment and are not expected to change.

5

Also worth noting, if you know the index, you can manually type in the OPC Item Path using the index instead (e.g. ns=2;s=Foo), but if you drag and drop from the OPC Browser it will use the URI for index 2+ instead.

6

How can I find that index?

7

Read the server's NamespaceArray variable and find the index of the corresponding URI, use a 3rd party UA client, or by some other out of bands means - maybe the software you use to configure this server can tell you.

8

I'll do some looking and report back! Thanks Kevin!

9

I tried different indexes, and it seems to be at index 2. I'll see if I can find a third party OPC-UA client that can confirm that.