We typically run a #6 combined EGC/GEC on all residential systems just to keep it simple. The cost difference is typically negligible. We use irreversible C-crimps to combine the wires in a roof mounted junction box.
*Jason Szumlanski* *Fafco Solar* On Wed, Nov 28, 2012 at 10:56 PM, mac Lewis <maclew...@gmail.com> wrote: > Hello wrenches, > > What constitutes a separately derived system? Would you consider a > breaker tied enphase system a separately-derived system? Suddenly, > inspectors in our AHJ are considering all PV systems separately derived > systems and thus requiring applying GEC sizing (as opposed to EGC sizing) > from the inverter(s) to the tie in point. This does not jive with my > understanding. Would like to hear other thoughts about this. > > Here is the definition of a separately derived system as per 2008 NEC > Article 100 Definitions: > > *Separately Derived System*: *A premises wiring system whose power is > derived from a source of electric energy or equipment other than a service. > Such systems have no direct electrical connection, including a solidly > connected grounded circuit conductor, to supply conductors originating in > another system.* > > For your enphase systems do you size your ground from roof to the breaker > panel as an EGC or a GEC? > > > Thanks in advance for your thoughts. > > -- > > > > Mac Lewis > > * > > "Yo solo sé que no sé nada." -Sócrates > * > > _______________________________________________ > List sponsored by Home Power magazine > > List Address: RE-wrenches@lists.re-wrenches.org > > Options & settings: > http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org > > List-Archive: > http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org > > List rules & etiquette: > www.re-wrenches.org/etiquette.htm > > Check out participant bios: > www.members.re-wrenches.org > > >
_______________________________________________ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options & settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules & etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org