Yes, in moderation — for example, when you are trying to use the logo at a small size that renders the wordmark unreadable. Another example would be using the standalone crest as a recurring element in a PowerPoint presentation.
In limited circumstances, with size constraints, it may also be acceptable to keep “Wisconsin” (or, for secondary logos, the department/unit name) and remove the “University of Wisconsin–Madison” line of the wordmark. For approval, contact University Marketing.
For most applications, the W Crest should be used at a minimum height of .5 inch.