+1. John Wiles is awesome—and he would never mistake PV source or array circuits for a service. Not only are PV power circuits not a service, but PV systems (inverter output circuits) are not a service. The NEC defines all of this as power production equipment (705.2).
By definition a service can only be provided by a "serving utility" (Article 100). That definition does not apply to PV systems. Having said that, Section 230.82(6) does allow PV systems to connect to the supply side of a service disconnect. But that allowance doesn't magically change the PV system into a service; it is still (parallel) power production equipment. If you're still in the planning phase, Nick, it is a good idea to see if they will allow you to use MC "that complies with 250.118(10)" according to 690.31(E) in NEC 2011. DCB On Nov 9, 2012, at 7:44 AM, Dave Click wrote: > Nick, what the AHJ is telling you may actually be in reference to 250.97; for > most PV output circuits (yes these are necessarily dc) this bonding > requirement applies since array VOC > 250 VDC. As Kent just pointed out, > these dc conductors clearly don't meet the NEC definition of a service. > > "250.97 Bonding for Over 250 Volts. For circuits of over 250 volts to ground, > the electrical continuity of metal raceways and cables with metal sheaths > that contain any conductor other than service conductors shall be ensured by > one or more of the methods specified for services in 250.92(B), except for > (B)(1)..." followed by an exception. > > Seems that FMC is OK as an EGC if your conductors have <20A OCPDs, which I > imagine you do, but that FMC also can't be longer than 6' (see 250.118(5)). > So I think your AHJ is probably right and I just learned something. If you're > running a separate EGC anyway, you may want to ask why this bonding business > is so important-- but I don't have an NEC reference on this to help you argue > this. Maybe the AHJ would allow you to just run MC cable as the 2011 NEC > allows. > > John Wiles is awesome. Someone on this list had to say it. > > DKC > > On 2012/11/8 23:22, Nick Vida wrote: >> Hi Wrenches, >> >> Thanks for you comments. Fun for the day is hearing they want to apply >> section 230 about service conductors and say that flex is not >> a metallic raceway because it is no good for bonding. They are defining >> the pv source circuits as a service. >> I am getting a distinct Wiles vibe here. >> >> I find it so annoying when they try to put out these distinctions with >> no code, no city ordinance and not even an internal memo, especially >> when they remain obstinate without going to the trouble to actually >> legitimize the interpretation. >> >> Dan- are the output circuits necessarily DC? I would have to look at NEC >> for a minute, but it doesn't seem to add up to me right now. >> >> Thanks, >> >> Nick Vida >> >> >> _______________________________________________ >> 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 >
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