" An AC breaker is far more likely to trip than a DC string fuse"
I completely disagree. We have never, not once, had to reset a tripped inverter output circuit AC breaker that I know of, but have replaced many dozens of DC string fuses and GFCI fuses in inverters, most of the time for undiagnosed failures. There is a reason we keep a good supply of 1A, 15A, and 20A Littlefuses in a drawer here. Jason Szumlanski On Wed, Apr 30, 2014 at 9:56 AM, Drake <drake.chamber...@redwoodalliance.org > wrote: > There are good reasons to want to put AC combiners under modules, but > some reasons not to want to. > > An AC breaker is far more likely to trip than a DC string fuse, due to the > surge availability. As a PV system is designed to last a minimum of 25 > years, the installer might not be the one to sort out problems decades down > the line. > > A strategy I prefer would be to use a SolaDeck as a junction box. Run > small wires to a convenient AC combiner location. > > > At 12:43 PM 4/29/2014, you wrote: > > Dave > > I agree, in the case of microinverters, you already have a main PV System > disconnect at the Load Panel to shut down the system that is readily > accesible. I would consider the disconnect on the roof as a supplemental > disconnect for the purposes of maintenance by authorized personal that only > needs to be accessible. > > Bill > > > On Tue, Apr 29, 2014 at 8:44 AM, Dave Click <davecl...@fsec.ucf.edu > > wrote: > I think 240.24(A)(4) allows the installation of the inverter OCPDs in > the SolaDeck hidden under a module. > > 240.24 Location in or on Premises. > (A) Accessibility. Overcurrent devices shall be readily accessible and > shall be installed so that the center of the grip of the operating handle > of the switch or circuit breaker, when in its highest position, is not more > than 2.0 m (6 ft 7 in.) above the floor or working platform, unless one of > the following applies: > ... > (4) For overcurrent devices adjacent to utilization equipment that they > supply, access shall be permitted to be by portable means. > > > And if panelboards / fused safety switches are allowed to have > screwed-down covers over the OCPDs, I'd think that installing a removable > module over these OCPDs would meet NEC. I guess an AHJ could argue that > this requires TWO covers be removed, unlike a panelboard or a switch. > > DKC > > > On 2014/4/29, 11:15, Jason Szumlanski wrote: > > 690.9(D) is not applicable to the original discussion because we were > talking about an Inverter output circuit, not a PV Source or Output circuit. > > 690.34 may apply if you call a SolaDeck with breakers a junction box, but > I can see that being a stretch in the mind of many. > > My and Ray's question about the screws on the SolaDeck cover itself > requiring a tool to render it accessible is still an issue if the breakers > themselves need to be "readily accessible," but that would also apply to a > Midnite MNPV, which also has a cover with a screw. > > > Jason Szumlanski > > On 4/28/2014 5:57 PM, Bill Brooks wrote: > > > Read 690.9(D) and 690.34. Not sure where this “hysteriarun for the > border” sentiment is coming from. > > > > 690.9(D) Photovoltaic Source and Output Circuits. Listed PV > > overcurrent devices shall be required to provide overcurrent > > protection in PV source and output circuits. The overcurrent > > devices shall be accessible but shall not be required to > > be readily accessible. > > > > 690.34 Access to Boxes. Junction, pull, and outlet boxes > > located behind modules or panels shall be so installed that > > the wiring contained in them can be rendered accessible > > directly or by displacement of a module(s) or panel(s) secured > > by removable fasteners and connected by a flexible > > wiring system. > > > > This is not a change. Please help me understand the concern. > > > > Bill Brooks. > > > > > > From: re-wrenches-boun...@lists.re-wrenches.org > [mailto:re-wrenches-boun...@lists.re-wrenches.org<re-wrenches-boun...@lists.re-wrenches.org>] > On Behalf Of Ray Walters > Sent: Monday, April 28, 2014 2:23 PM > To: RE-wrenches > Subject: Re: [RE-wrenches] (no subject) > > > > Interesting so does "require a tool" include taking a screw off the cover > plate of the combiner box, too? > What a game changer. I'm going to Mexico for my next project; I'll > actually enjoy even more being the sole AHJ on the project. > > > R.Ray > Walters > > > CTO, Solarray, > Inc > > > Nabcep Certified PV Installer, > > > Licensed Master > Electrician > > > Solar Design > Engineer > > > 303 > 505-8760 <303%20505-8760> > > > On 4/28/2014 2:52 PM, Michael Morningstar wrote: > > Readily accessible is now defined in the 2014 NEC. Installing OCPD’s > underneath a module is a major faux paux, and I can’t imagine any AHJ > thinking otherwise. Having to remove a module in order to reset a breaker, > what a drag. > > > > "Capable of being reached quickly for operation, renewal or inspection > without requiring those concerned to use a tool, to climb over, remove > obstacle or other.” > > > > Michael > > > > > > > > > > On Apr 28, 2014, at 10:29 AM, William Miller <will...@millersolar.com > > wrote: > > > > You call it a solar panel, I call it a glass j-box cover plate. > > William > > Miller Solar > > > On Apr 28, 2014, at 9:21 AM, Jason Szumlanski <ja...@fafcosolar.com> > wrote: > > If that is the interpretation, > I don't see how the breakers are "readily accessible" in a SolaDeck > mounted anywhere, regardless of whether it is under a module. It > requires removal of four screws (using a tool) to access the breakers > inside the enclosure. It's all up to the AHJ. It has not been an issue > locally here. I can see how other jurisdictions may not > concur. > > > > _______________________________________________ > 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<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 > > 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 > > > > _______________________________________________ > 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 > > > > > > -- > William Hoffer > 161 SE Fourth Ave > P.O. Box 1823 > White Salmon, WA 98672-1823 > suneng...@gmail.com <bhof...@sunergyengineeringservices.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 > > _______________________________________________ > 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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