I have a 13.2KV-480/277V transformer that is existing. Is it possible to tap the feed right before the primary side to a second transformer of the same capacity approximately 500 ft away?
If this is a utility owned transformer, why are you considering tapping into the cable? If this is a newer type transformer, it is probably dead front construction and probably has feed through bushings that will allow you to install your new run right off the bushings with another set of elbow terminators.