Equipment and Location are just Group Items with one of a predefiened set of Item tags applied. Point Items are your existing Items with at least one of the predefined Point tags and an optional Properties tag applied. And these are standard Item tags, nothing special. See Items | openHAB for the syntax. See HABot Walkthrough (2/n): Semantic Tagging & Item Resolving for how to apply the semantic model using .items files. Yes, the model has been around long before OH 3 and it’s the same model as used by HABot.
So, to create an Equipment, create a Group Item with an Equipment tag. Then add the Items that are part of that Equipment to the Group. Then add Point/Properties tags to the Items you added to the Equipment Group. It’s all done with standard Item concepts (Group membership and Item tags).
Locations are the same. They are just a plain old Group Item with a Location tag. Equipment and Points are made a part of a location through Group membership.
Because the list is changing, you’ll want to look in MainUI for the current list of supported tags for Location, Equipment, Points, and Properties. Just click on the “semantic tag” field and you’ll see a list of the currently supported tags. The link above shows an old set which is still correct but not complete.
Using Thing autodiscovery, “Create Equipment from Thing” and the automatically built parts of the Overview Page based on the semantic model, I can do the same. I’m not saying one way is better than the other, just that both support these kinds of use cases. Thats the part I want future readers to understand. You don’t want to learn a new way of doing things and that is perfectly valid and fine. But I don’t want people to think that it’s impossible to do with managed Items too.