Sole connection indicates that a GEC is connected to only one type of grounding electrode. This term is easily mis- understood. For example, a GEC can be connected to more than one grounding electrode—say, two ground rods—and still be considered to have a sole connection. Similarly, multiple GECs connected to the same grounding electrode are each considered to have a sole connection. When GECs have a sole connection, their maximum size is limited per NEC Sections 250.66 for an ac system and 250.166 for a dc system. The 2014 NEC adds some clarification on this.
Brian Mehalic NABCEP Certified Solar PV Installation Professional™ R031508-59 IREC ISPQ Certified Affiliated Instructor/PV US-0132 PV Curriculum Developer and Instructor Solar Energy International http://www.solarenergy.org On Wed, Sep 18, 2013 at 4:52 PM, Aladdin Solar <cpick...@aladdinsolar.com>wrote: > ** > Yes, Jay, this is a TenKSolar system -- they certainly do have a habit of > taking the 'thinking outside the box' approach! > > The microinverter manufacturer states in their installation manual, > "Connect the grounding electrode conductor to the microinverter ground > clamp" so it's quite clear we are dealing with GEC rules. > > Thanks for all your comments and the reminder of the NEC 250.166(C) > exception which I hadn't really connected with before. > > I'm having difficulty understanding what the requirement in that paragraph > actually means. When it states "that portion of the grounding electrode > conductor that is the sole connection to the grounding electrode shall not > be required to be larger than 6AWG..." -- what does "that portion" and > "sole connection" mean? If we have a number of GEC branches from that are > irreversably spliced to a single 6AWG conductor bonded to the grounding > electrode, do those various GECs affect the "that portion" and "sole > connection" at all? > > Charlie Pickard > NABCEP Certified PV Installation Professional ™ > Aladdin Solar, LLC > > > > ----- Original Message ----- > *From:* Bill Brooks <billbroo...@yahoo.com> > *To:* 'RE-wrenches' <re-wrenches@lists.re-wrenches.org> > *Sent:* Wednesday, September 18, 2013 2:42 PM > *Subject:* Re: [RE-wrenches] GEC sizing for a high amp,low voltage PV > system with microinverters > > Nick,**** > > ** ** > > Thanks for the clarification—it is a mysterious threaded hole….**** > > ** ** > > Bill.**** > > ** ** > > *From:* re-wrenches-boun...@lists.re-wrenches.org [mailto: > re-wrenches-boun...@lists.re-wrenches.org] *On Behalf Of *Nick Soleil > *Sent:* Wednesday, September 18, 2013 10:19 AM > *To:* RE-wrenches > *Subject:* Re: [RE-wrenches] GEC sizing for a high amp, low voltage PV > system with microinverters**** > > ** ** > > Hi Bill and wrenches,**** > > To clarify, our new Enphase M250 microinverter does not have a grounding > terminal. The grounding of the M250 will be provided through the Engage > cable. We only have a hole in the lid, in the rare case that a lug will be > desired or required by the AHJ, but we do not provide the grounding clip > with the microinverter. A grounding terminal can be added to the > microinverter. We have an application note on alternate grounding methods > for the M250, if needed.**** > > ** ** > > ** ** > > > > __________ Information from ESET NOD32 Antivirus, version of virus > signature database 8815 (20130918) __________ > > > The message was checked by ESET NOD32 Antivirus. > > http://www.eset.com > > ------------------------------ > > _______________________________________________ > List sponsored by Home Power magazine > > List Address: RE-wrenches@lists.re-wrenches.org > > Change email address & 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 > > > > > __________ Information from ESET NOD32 Antivirus, version of virus > signature database 8815 (20130918) __________ > > > The message was checked by ESET NOD32 Antivirus. > > http://www.eset.com > > > > __________ Information from ESET NOD32 Antivirus, version of virus > signature database 8817 (20130918) __________ > > > The message was checked by ESET NOD32 Antivirus. > > http://www.eset.com > > _______________________________________________ > List sponsored by Home Power magazine > > List Address: RE-wrenches@lists.re-wrenches.org > > Change email address & 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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