can Alias tag scope be different from base tag?

[TheWaterboy]

A program I am working with has all its tags in the controller scope. The tags that needed meaningful names for SCADA consumption were aliased. Being the OCD kind of person I tend to become when trying to understand someone else's code, I exported the tags and changed their scopes to appropriate places and imported. All the tags looks right and there were no errors . . . however... The Alias and Base tags appear to have become disconnected from each other with no other outward error.

I have tags named N119[15] for example, they are aliased to a meaningful name like Vat_3_Weight. I placed N119 into program scope and let Vat_3_Weight remain in controller scope since that is what SCADA will use.

Next, using the tag organizer I enter a value into the global tag Vat_3_Weight. That value does not show up in the program scoped base tag of N119.

I didn't think that the alias and base had to share the same scope, if true that certainly weakens the usefulness of an alias.

What have I missed here?

 

[TConnolly]

An alias tag can be program scope when the base tag is controller scoped.

However, you cannot have a program scoped base tag with a controller scoped alias, nor can you have a programed scoped tag alias a base tag locally scoped in another program.

 

[TheWaterboy]

Well then . . . that is less than optimal.
I looked for that to be in the documentation but as yet I have not located that restriction.