This video covers how to correctly edit electrical families that contain symbolic representations for the objects. For example, a receptacle is represented by a circle and two lines when set to course or medium detail level. For many electrical items you will have a physical family with a nested symbolic that adjust with the scale of the view. This video covers how to edit that nested symbol. Along with the family editing, this video also covers how to adjust line weight and color of symbolic families in Revit.
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