This post isn’t about “tiled UVs” (“UDIM”), it’s about multiple UV sets (layouts).
Polygon mesh models can have multiple UV sets. this becomes useful when the UV layout that is optimal for a certain texture isn’t efficient for different texture (in the same material).
For example, we might have a model of furniture, or clothing, in which the UV layout that is best for the fabric weave pattern, isn’t the best for dirt and wear & tear, or stickers.
In such cases we can define different UV sets for the model, each suitable for a different texture.
In this example, having a separate UV Set for the logo texture allows placing it without affecting the checker texture that is displayed an all the surfaces:
To create multiple UV sets:
In the UV editor view, from the UV Sets menu, select UV Set Editor to open the UV Set Editor:
In the UV Set Editor, press the New button to create a new UV Set and double click it in the list to rename it:
Close the UV Sets Editor.
The UV Editor view now displays the new UV Set that is empty, and UV creation and editing operations will now affect the new UV Set.
To switch to edit a different UV Set, select it from the list at the bottom of the UV Sets menu:
To link a texture to a specific UV Set:
Make sure the texture is connected to the material set for the model.
Select the model.
Open Windows > Relationship Editors > UV Linking > Texture-Centric:
Select the wanted texture from the material texture list on the left and select the wanted UV Set from the models UV Sets list on the right: