Can some one tell me how important is it to consider AVR in arcflash studies and its impact in the studies and incident energy calculations.

In a generator with an external exciter, such as a GE EX2100 static exciter, there is a regular maintenance duty that is absolutely insane, changing the brushes. Letting a brush holder loose while changing a brush can result in welding parts of the brush assembly together, and ruining your whole day. I also need data on modelling the AVR for arc flash hazard while changing brushes. The equation to use is very simple, but getting the voltage, bolted fault current (assuming arc current is half), and clearing time to use, and what working distance should be used, is proving to be difficult. Can any vendors provide a model to use for arc calculation at brush holders???

You may want want to post your question in the appropriate forum section or perhaps the moderator will move it there.
You may want to read the specs on the exciter as there may be something on max available fault current and allowable time for that before it shuts down. That would give some worst case info and the voltage you should know and the working distance is probably about 18"

Gautham - this is the same question that you posted in another thread. As with my response in the other thread, this should be a new thread and please do not duplicate postings. I have notified the moderator to move your other posting to a new thread and this one should be deleted as it is a duplicate posting.
It just makes it easier for everyone using this valuable forum.