Dimension to the center of an object in elevation view

[Anonymous]

I'm relatively new to Revit (I'm migrating over from AutoCAD), so I'm trying to figure out the differences in Revit with dimensioning compared to AutoCAD.  I have a specific example I'm hoping to get help with.  When I'm in a wall evelation view, I would like to place a dimension to indicate the height of a wall mounted TV from the floor to the horizontal centerline of the TV.  I'm used to AutoCAD snapping the dimension to that TV's horizontal centerline for me, but this doesn't occur in Revit.  Hoping for clarification on how I can make this happen.  

I have a duplex wall outlet on that same elevation view, and my dimension snaps to the horizontal centerline of that object, so I'm not sure what the difference is between that and my TV object.

Thanks.

Mike

[ToanDN · Accepted solution]

Edit the family and make sure there is a Reference Plane drawn where the centerline should be, and is Set as Center (Elevation) from the Properties.  That also allows you to set the extension line of the dimensions to a special pattern and even a centerline symbol if they measured to a centerline of a family component.