<html><head></head><body><div style="color:#000; background-color:#fff; font-family:Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:13px"><div id="yui_3_16_0_ym19_1_1505320624260_15247">Dear Wrenches,</div><div id="yui_3_16_0_ym19_1_1505320624260_15246"><br></div><div id="yui_3_16_0_ym19_1_1505320624260_15245">I have a residential ground mounted installation that did not pass inspection due to schedule 40 PVC conduit stubbing up from a trench to the inverters and subpanel. The inverters and subpanel are hung on Unistrut, which is attached to the rear posts of the ground rack. There is a second subpanel next to the main on the side of the house with schedule 40 stubbing up into it as well.</div><div id="yui_3_16_0_ym19_1_1505320624260_15415"><br></div><div id="yui_3_16_0_ym19_1_1505320624260_15604">The inspector insists that conduit stubbing out of the ground is subject to physical damage and needs to be replaced with schedule 80 even though it is not in an area where vehicles or mobile equipment are used. Is there a generally accepted definition of "areas of physical damage" as seen in 350.10 (F)?<br></div><div id="yiv9409159970"><div id="yui_3_16_0_ym19_1_1505320624260_15244"><div id="yui_3_16_0_ym19_1_1505320624260_15243" style="color:#000;background-color:#fff;font-family:Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:13px;"><div id="yiv9409159970yui_3_16_0_ym19_1_1505320624260_14148"><span></span></div> <div id="yui_3_16_0_ym19_1_1505320624260_15242" class="yiv9409159970qtdSeparateBR"><br><div id="yui_3_16_0_ym19_1_1505320624260_15764">The inspector has said he would consider my argument if I can provide language from the Code to back up my position.</div><div id="yui_3_16_0_ym19_1_1505320624260_15749"><br></div><div id="yui_3_16_0_ym19_1_1505320624260_15748">Any help is greatly appreciated.</div><div id="yui_3_16_0_ym19_1_1505320624260_15728">Jerry Caldwell</div><div><br></div></div></div></div></div><div class=".yiv9409159970yahoo_quoted"> <div style="font-family:Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:13px;"> <div style="font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:16px;"> <div dir="ltr"><font face="Arial" size="2"> On Saturday, October 4, 2008 8:28 AM, Geoff Greenfield <geoff@third-sun.com> wrote:<br></font></div> <br><br> <div class="yiv9409159970y_msg_container"><div dir="ltr">thanks for input Bill, and also for tip on zipties. We have dealt with intermittent groundfaults caused by faulty xlp! Had to spray water on array to "find" it. PITA! Almost makes me want to submerge the spool next time and do my own test. <br></div><div dir="ltr"><br></div><div dir="ltr"> <br></div><div dir="ltr"><br></div><div dir="ltr">For a brighter energy future,<br></div><div dir="ltr"><br></div><div dir="ltr">Geoff Greenfield<br></div><div dir="ltr">President<br></div><div dir="ltr">Third Sun Solar & Wind Power Ltd.<br></div><div dir="ltr">340 West State Street, Unit 25<br></div><div dir="ltr">Athens, OH 45701<br></div><div dir="ltr"><br></div><div dir="ltr">740.597.3111 Fax 740.597.1548<br></div><div dir="ltr">www.Third-Sun.com<br></div><div dir="ltr"><br></div><div dir="ltr">Clean Energy - Expertly Installed<br></div><div dir="ltr"><br></div><div dir="ltr"><br></div><div dir="ltr"><br></div><div dir="ltr"><br></div><div dir="ltr"><br></div><div dir="ltr"><br></div><div dir="ltr">----- Bill Brooks <<a rel="nofollow" ymailto="mailto:billbrooks7@yahoo.com" target="_blank" href="mailto:billbrooks7@yahoo.com">billbrooks7@yahoo.com</a>> wrote:<br></div><div dir="ltr">> Geoff,<br></div><div dir="ltr">> <br></div><div dir="ltr">> SS zip ties are good, but you must be very careful not to pull them tight.<br></div><div dir="ltr">> They should only be snug, not tight. These SS zip ties have been shown to<br></div><div dir="ltr">> cause ground faults in many cases. Commercial rooftops are accessible, but<br></div><div dir="ltr">> not readily accessible. Conductors must be supported properly and protected<br></div><div dir="ltr">> from physical damage. The conductors must follow structural members. If they<br></div><div dir="ltr">> leave structural members, they must be in a raceway of some kind. A variety<br></div><div dir="ltr">> of options there.<br></div><div dir="ltr">> <br></div><div dir="ltr">> Bill.<br></div><div dir="ltr">> <br></div><div dir="ltr">> -----Original Message-----<br></div><div dir="ltr">> From: <a rel="nofollow" ymailto="mailto:re-wrenches-bounces@lists.re-wrenches.org" target="_blank" href="mailto:re-wrenches-bounces@lists.re-wrenches.org">re-wrenches-bounces@lists.re-wrenches.org</a><br></div><div dir="ltr">> [mailto:<a rel="nofollow" ymailto="mailto:re-wrenches-bounces@lists.re-wrenches.org" target="_blank" href="mailto:re-wrenches-bounces@lists.re-wrenches.org">re-wrenches-bounces@lists.re-wrenches.org</a>] On Behalf Of Geoff<br></div><div dir="ltr">> Greenfield<br></div><div dir="ltr">> Sent: Friday, October 03, 2008 7:19 AM<br></div><div dir="ltr">> To: RE-wrenches<br></div><div dir="ltr">> Cc: Randy; Kent Phillips<br></div><div dir="ltr">> Subject: [RE-wrenches] Protection of Conductors<br></div><div dir="ltr">> <br></div><div dir="ltr">> Hey wrenchers... we have an internal debate going about a code section<br></div><div dir="ltr">> interpretation... "subject to physical damage". Code compliance is a must,<br></div><div dir="ltr">> best practice is an expectation (...weighed against material and labor cost<br></div><div dir="ltr">> (prevailing wage job)). <br></div><div dir="ltr">> <br></div><div dir="ltr">> Application is a flat roof with no public access (locked hatch). We are<br></div><div dir="ltr">> using DP+W "Power-tube" flat roofing system for the first time... the<br></div><div dir="ltr">> question is how to deal with the inter-row N-S wire runs... about 100 gaps<br></div><div dir="ltr">> about 24" between the E-W rows of panels. There are plenty of 2"x2" strut<br></div><div dir="ltr">> members running under the array N-S. We will "exit" the array field in<br></div><div dir="ltr">> ridgid conduit to combiner boxes.<br></div><div dir="ltr">> <br></div><div dir="ltr">> The flat roof system we usually use has built in wire trays... using this<br></div><div dir="ltr">> new system has brought up this question... Our options include dressing the<br></div><div dir="ltr">> XLP bundles with SS zip ties alongside the N-S struts, or using Galv. RMC,<br></div><div dir="ltr">> strapped, with bushings (or S-80 PVC) at all these walkways... or using<br></div><div dir="ltr">> Unistrut (w/cap) as a lay in wireway (to speed up labor (debatable)).<br></div><div dir="ltr">> <br></div><div dir="ltr">> Below are some of the code references... the basic question seems to be:<br></div><div dir="ltr">> does the limited access of this roof keep us out of "subject to physical<br></div><div dir="ltr">> damage"? What is a "Readily accessible location?"<br></div><div dir="ltr">> <br></div><div dir="ltr">> Thanks everyone.<br></div><div dir="ltr">> <br></div><div dir="ltr">> For a brighter energy future,<br></div><div dir="ltr">> <br></div><div dir="ltr">> Geoff Greenfield<br></div><div dir="ltr">> President<br></div><div dir="ltr">> Third Sun Solar & Wind Power Ltd.<br></div><div dir="ltr">> 340 West State Street, Unit 25<br></div><div dir="ltr">> Athens, OH 45701<br></div><div dir="ltr">> <br></div><div dir="ltr">> 740.597.3111 Fax 740.597.1548<br></div><div dir="ltr">> www.Third-Sun.com<br></div><div dir="ltr">> <br></div><div dir="ltr">> Clean Energy - Expertly Installed<br></div><div dir="ltr">> <br></div><div dir="ltr">> <br></div><div dir="ltr">> > <br></div><div dir="ltr">> > Next, one might argue, I suppose, that the racking system itself, acts<br></div><div dir="ltr">> > as<br></div><div dir="ltr">> > protection and that the conductors should therefore, not be considered<br></div><div dir="ltr">> > to<br></div><div dir="ltr">> > be exposed. I disagree based on NEC definition. That stated, I<br></div><div dir="ltr">> > would<br></div><div dir="ltr">> > consider these NEC references for more perspective:<br></div><div dir="ltr">> > <br></div><div dir="ltr">> > Pretty straightforward NEC 100 Definitions Exposed (as applied to<br></div><div dir="ltr">> > wiring<br></div><div dir="ltr">> > methods): On or attached to the surface... <br></div><div dir="ltr">> > <br></div><div dir="ltr">> > NEC 300.4 gives various cases for protection against physical damage<br></div><div dir="ltr">> > requirements. Long article. Worth a read. Does not address our<br></div><div dir="ltr">> > exact<br></div><div dir="ltr">> > case, but I would say that the following methods would be appropriate<br></div><div dir="ltr">> > based on similar cases... <br></div><div dir="ltr">> > <br></div><div dir="ltr">> > NEC 344.10 (A)(1) Galvanized steel and stainless steel RMC. ...shall<br></div><div dir="ltr">> > be<br></div><div dir="ltr">> > permitted under all atmospheric conditions and occupancies. <br></div><div dir="ltr">> > <br></div><div dir="ltr">> > NEC 352.10(f) Exposed. PVC conduit shall be permitted for exposed<br></div><div dir="ltr">> > work.<br></div><div dir="ltr">> > PVC conduit used exposed in areas of physical damage shall be<br></div><div dir="ltr">> > identified<br></div><div dir="ltr">> > for the use. FPN: PVC conduit, Type Schedule 80, is identified for<br></div><div dir="ltr">> > areas<br></div><div dir="ltr">> > of physical damage. <br></div><div dir="ltr">> > <br></div><div dir="ltr">> > Also,<br></div><div dir="ltr">> > <br></div><div dir="ltr">> > NEC 690.31(A) ...Where photovoltaic source and output circuits<br></div><div dir="ltr">> > operating<br></div><div dir="ltr">> > at maximum system voltages greater than 30 volts are installed in<br></div><div dir="ltr">> > readily<br></div><div dir="ltr">> > accesible locations, circuit conductors shall be installed in a<br></div><div dir="ltr">> > raceway.<br></div><div dir="ltr">> > <br></div><div dir="ltr">> > One might argue, then, why don't the module interconnects have to be<br></div><div dir="ltr">> > protected, also...<br></div><div dir="ltr">> > <br></div><div dir="ltr">> > NEC 690.31(B) is really the key to all of this: Single-Conductor<br></div><div dir="ltr">> > Cable.<br></div><div dir="ltr">> > Single-conductor cable type USE-2, and single-conductor cable listed<br></div><div dir="ltr">> > and<br></div><div dir="ltr">> > labeled as photovoltaic (PV) wire shall be permitted in exposed<br></div><div dir="ltr">> > outdoor<br></div><div dir="ltr">> > locations in photovoltaic source circuits FOR PHOTOVOLTAIC MODULE<br></div><div dir="ltr">> > INTERCONNECTIONS within the photovoltaic array. <br></div><div dir="ltr">> > <br></div><div dir="ltr">> > So, I suppose that if our source circuit interconnections extend from<br></div><div dir="ltr">> > row<br></div><div dir="ltr">> > to row, then we can leave those exposed. I don't like it, but it<br></div><div dir="ltr">> > would<br></div><div dir="ltr">> > probably have to be accepted. <br></div><div dir="ltr">> > <br></div><div dir="ltr">> ><br></div><div dir="ltr">> _______________________________________________<br></div><div dir="ltr">> List sponsored by Home Power magazine<br></div><div dir="ltr">> <br></div><div dir="ltr">> List Address: <a rel="nofollow" ymailto="mailto:RE-wrenches@lists.re-wrenches.org" target="_blank" href="mailto:RE-wrenches@lists.re-wrenches.org">RE-wrenches@lists.re-wrenches.org</a><br></div><div dir="ltr">> <br></div><div dir="ltr">> Options & settings:<br></div><div dir="ltr">> <a rel="nofollow" target="_blank" href="http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org">http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org</a><br></div><div dir="ltr">> <br></div><div dir="ltr">> List-Archive:<br></div><div dir="ltr">> <a rel="nofollow" target="_blank" href="http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org">http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org</a><br></div><div dir="ltr">> <br></div><div dir="ltr">> List rules & etiquette:<br></div><div dir="ltr">> www.re-wrenches.org/etiquette.htm<br></div><div dir="ltr">> <br></div><div dir="ltr">> Check out participant bios:<br></div><div dir="ltr">> www.members.re-wrenches.org<br></div><div dir="ltr">> <br></div><div dir="ltr">> _______________________________________________<br></div><div dir="ltr">> List sponsored by Home Power magazine<br></div><div dir="ltr">> <br></div><div dir="ltr">> List Address: <a rel="nofollow" ymailto="mailto:RE-wrenches@lists.re-wrenches.org" target="_blank" href="mailto:RE-wrenches@lists.re-wrenches.org">RE-wrenches@lists.re-wrenches.org</a><br></div><div dir="ltr">> <br></div><div dir="ltr">> Options & settings:<br></div><div dir="ltr">> <a rel="nofollow" target="_blank" href="http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org">http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org</a><br></div><div dir="ltr">> <br></div><div dir="ltr">> List-Archive: <a rel="nofollow" target="_blank" href="http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org">http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org</a><br></div><div dir="ltr">> <br></div><div dir="ltr">> List rules & etiquette:<br></div><div dir="ltr">> www.re-wrenches.org/etiquette.htm<br></div><div dir="ltr">> <br></div><div dir="ltr">> Check out participant bios:<br></div><div dir="ltr">> www.members.re-wrenches.org<br></div><div dir="ltr">> <br></div><div dir="ltr"><br></div><div dir="ltr">_______________________________________________<br></div><div dir="ltr">List sponsored by Home Power magazine<br></div><div dir="ltr"><br></div><div dir="ltr">List Address: <a rel="nofollow" ymailto="mailto:RE-wrenches@lists.re-wrenches.org" target="_blank" href="mailto:RE-wrenches@lists.re-wrenches.org">RE-wrenches@lists.re-wrenches.org</a><br></div><div dir="ltr"><br></div><div dir="ltr">Options & settings:<br></div><div dir="ltr"><a rel="nofollow" target="_blank" href="http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org">http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org</a><br></div><div dir="ltr"><br></div><div dir="ltr">List-Archive: <a rel="nofollow" target="_blank" href="http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org">http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org</a><br></div><div dir="ltr"><br></div><div dir="ltr">List rules & etiquette:<br></div><div dir="ltr">www.re-wrenches.org/etiquette.htm<br></div><div dir="ltr"><br></div><div dir="ltr">Check out participant bios:<br></div><div dir="ltr">www.members.re-wrenches.org<br></div><div dir="ltr"><br></div><br><br></div> </div> </div> </div></div></body></html>