Re: 320 Amp Service, Tow 200A Panels?
Sounds like the utility supply's the service equipment in your case (up to the meter) this only leaves you with two option's: Install two disconnects one on each side of the meter if space permits, the disconnect feeding the apartment can have 2/0 all the way to the no-main panel in the apartment 310.15(B)(6). But if the shop is a commercial space it would require 3/0 to just the shop's panel, The second option is to locate both panels in the same location with main breakers but both panels will have to be accessible to both the owner and the renter. I would pick the first choice. In ether case the dwelling only needs 2/0 copper ran to it.
Wayne A. From: N.W.Indiana
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