Standard OPC Tag Property Substitution

Ignition
1

I am used to using tag property substitution within the definition of tags inside of a UDT. So, I would've expected the same property substitutions to work in a standard tag definition.

For instance, in a UDT it works to define the OPC Item Path as such:

ns=1;s=[{Device_pump}]{AOI_Name_pump}.{TagName}

Where {Device_pump} and {AOI_Name_pump} are parameters to the UDT.

However, it seems I cannot use {Tag_Name} within the OPC Item Path definition of a standard OPC tag, like so:

ns=1;s=[PLC]{Tag_Name}

The tag name is not substituted when I inspect the tag path in the tag browser:
image

Is that correct, or am I missing something?
Is there a way to make this work?

2

You're not missing anything; "standard" tags do not perform the pre-evaluation step UDTs do to evaluate references in that format. Your option in the short term is to use a UDT, even if it only has one member.

Longer term, we have some plans to improve this at the execution layer, but no idea when or exactly what that would look like.