Sketcher > Dimensioning Sketcher Geometry > Working with Dimension Tools > Reference Dimensions > About Reference Dimensions
About Reference Dimensions
You can create new reference dimensions, and you can convert existing dimensions to reference dimensions. Reference dimensions must have at least one section geometry entity.
The symbolic name for a reference dimension is rsd# REF, where # represents the dimension ID. You can refer to reference dimensions in Sketcher as sd# or as rsd#. Reference dimension names cannot be used as parameter names.
When you create a relation, you can use known and reference dimension on the right-hand side, however, carefully use the reference dimensions. Reference dimensions are dependent of the section geometry and require regeneration. Regeneration updates the section geometry, which updates the reference dimensions.
* If you click Sketch > Reference and place a dimension using only geometries that are external to the sketch, a known dimension is created.