ok, I have some more details; and I am totally new to arc flash. We have a 600a service and a 400a service coming off a pad mount transformer. The KVA rating of the transformer is worn off. But it's obviously designed around a 1000amps for both services coming into the building. It's a 208Y/120 and the primary side is most likely 7.2KV.
My position is senior plant mechanic/engineer. There's a lot of sub panels which I don't worry about.
My concern is the 600amp panel, which we go into once a year to vacuum the dust out, and look things over. We were a wood shop, and now we are a packaging plant. Still very dusty... The 600amp panel is about 50 feet from the pad mount, but is feed by parellel feeders. no doubt the fault current potential is there.
Do I need the full Nomex suit when going into the 600amp panel ? or is eye protection, and a good pair of gloves all that is necessary ?