Could not load parameter model

Hey guys!

I’ve created a Nested UDT with parameters and while attempting to run the wizard, I ran into an error without detail that says “Could not load parameter model”.

Any I dea why that may be happening?

I’m attaching the error as an image.

More info:
My child UDTs each have a parameter (called Offset) to be used as a pointer on where to start reading the data (since I’m reading Siemens’ DB).
Each tag uses this offset for the indirect addressing, so I get DB500.Real{Offset+n} (n being a fixed number on each tag since the structure is fixed).

Now, on My parent UDT, I have a “MainOffset” parameter, and on the children instances I have declared the Offset parameter as {MainOffset+n} (n being each UDT’s corresponding offset, fixed number}.

Anyone else seeing this? I have the same issue (not nested UDT’s) - the multi instance wizard has always thrown this error in Ignition 8 for me.

Hello Julian.

We’ve been investigating what the problem could be. The fact is that you must define a default tag provider and database in the project properties.

Once you’ve done this, the problem goes away.

Hope this might be helpfull for you.

1 Like

Sorry, a what again?

  • So, what you mean is that Ignition’s OPC Server isn’t the default provider?
  • And is a database is needed even if I’m not used archived tags?

Yes, database is necessary ever.

Tried to create the UDT in this folder

and put the default provider in project properties

Ignition’s OPC Server is not a tag provider at all. It is a provider of OPC items and subscriptions thereto. Tags within Ignition include more than just OPC items.

FWIW, there’s a great deal of sloppy terminology around OPC. OPC supplies items that may be tags in a target PLC or other device. They are not connected to tags in Ignition unless subscribed by a tag provider.