Hi,
So you question does not tell me much, I don't know if this is an API question or not. Sounds more like it is not so here is what I can tell you in regards to units from an imported linked CAD. Explicitly sets the unit of measure for imported geometry. The values are Auto-Detect, feet, inch, meter, decimeter, centimeter, millimeter, and Custom factor.
If you specify Auto-Detect for an AutoCAD file created in Imperial (English), then the file imports with feet and inches as the units. If the AutoCAD file was created in metric, then the file imports into Revit with millimeters as the units.
Read more at https://knowledge.autodesk.com/support/revit-products/learn-explore/caas/CloudHelp/cloudhelp/2014/EN...
and http://help.autodesk.com/view/RVT/2016/ENU/?guid=GUID-AB37F1CB-CF6B-4C15-B26A-D0F0F3EF1F2B
also remember that
Revit API forum is for API (Application Programming Interface) questions.
For non-API questions, please choose other forums that is more appropriate. For example,
Installation and licensing:
http://forums.autodesk.com/t5/installation-licensing/bd-p/24
Revit Architecture (including common platform product usage questions):
http://forums.autodesk.com/t5/revit-architecture/bd-p/133
Revit Structure:
http://forums.autodesk.com/t5/revit-structure/bd-p/153
Revit MEP:
http://forums.autodesk.com/t5/revit-mep/bd-p/188
In case it is an API question please elaborate a bit more your question in order to help you out with a better response.
Cheers,