<html><head><style type='text/css'>p { margin: 0; }</style></head><body><div style='font-family: Times New Roman; font-size: 12pt; color: #000000'>esteemed wrenches (or just steamed if youve been out in the hot lately)<div><br></div><div>I'm curious why more folks don't use the same flat roof ballasted rack approach for large ground mounts? Geotech weed barier and off we go... my initial calcs sat its a cost saver... my instinct says it viable, but my other instinct says "if it were this easy I would see it all the time (and I've never seen it)</div><div><br></div><div>what's up? frost heave/instability? wav-i-ness of the ground? better performance at steep angle worth all the extra cost (not according to my pencil with today's mod costs). Thoughts? <br><br>For a brighter energy future,<br><br>Geoff Greenfield<br>President<br>Third Sun Solar & Wind Power Ltd.<br>340 West State Street, Unit 25<br>Athens, OH 45701<br><br>740.597.3111 Fax 740.597.1548<br>www.Third-Sun.com<br><br>Clean Energy - Expertly Installed<br><br><br><br><br><br><br>----- "Dave Click" <daveclick@fsec.ucf.edu> wrote:
<br>> Thanks all.<br>> <br>> It was my understanding that we should still be running the conductors <br>> of the same circuit through the same raceway, even if it is the DC input <br>> into the inverter since that DC oscillates slightly (nowhere near as <br>> much as AC). I wasn't concerned about eddy currents in the FNMC of <br>> course but the metal box itself, a concern being voiced on this list <br>> before. I'd be more concerned about this if it were a 1MW inverter <br>> rather than a 7kW, but still.<br>> <br>> Thanks for the info on the GEC tap and I'm glad the split bolts work here.<br>> <br>> The conduit in question doesn't seem to be there just for physical <br>> protection; the wire runs from the east end of the array for 100'+ and <br>> only the last 3' are in conduit. If it were only for protection I'd be <br>> fine with it being open-ended on both ends, but since it's there to feed <br>> the conductors into the box, that's why I was treating it as a regular <br>> conduit that required a cord grip at the other end. Where do others make <br>> the distinction?<br>> <br>> Thanks,<br>> DKC<br>> <br>> -------- Original Message --------<br>> Subject: Re: [RE-wrenches] DC positive and negative in same conduit, <br>> other inspection issues<br>> From: Kelly Keilwitz, Whidbey Sun & Wind <kelly@whidbeysunwind.com><br>> To: RE Wrenches listserve <re-wrenches@lists.re-wrenches.org><br>> Date: 2009/8/19 21:10<br>> <br>> > Dave,<br>> > Only GEC's are subject to the "continuous" rule (250.64C). It sounds like<br>> > your are talking about an EGC tapped from the GEC.<br>> > <br>> > When splicing PV GEC's required under 690.47D, either together (from<br>> > separated arrays) or to the existing AC GEC (if close enough), we have been<br>> > allowed to use split bolts instead of irreversible splices, per 250.64D1,<br>> > "Grounding Electrode Conductor Taps" (at end of paragraph). I.E., the<br>> > "continuous" rule is only being applied to the main GEC.<br>> > <br>> > I agree with Kurt on the LTNMF being used only as extra (not required) wire<br>> > protection for the USE-2. We often do this when running PV conductors<br>> > between short separations in modules or rails. I would think that only<br>> > temperature and fill corrections would apply - and only if the length<br>> > requires.<br>> > <br>> > -Kelly<br>> > <br>> > Kelly Keilwitz, P.E.<br>> > Whidbey Sun & Wind, LLC<br>> > Renewable Energy Systems<br>> > NABCEP Certified PV Installer<br>> > 987 Wanamaker Rd, <br>> > Coupeville, WA 98239<br>> > PH & FAX 360-678-7131<br>> > sunwind@whidbeysunwind.com<br>> > <br>> > On 8/19/09 2:41 PM, "Dave Click" <daveclick@fsec.ucf.edu> wrote:<br>> > <br>> >> For the grounding electrode wiring, it seems that it's fine to me since<br>> >> they ran the continuous #6 to each rail and then to the rod, qualifying<br>> >> as the 690.47(D) supplemental electrode. But the split bolts tapping<br>> >> that GEC to "ground the disconnect," these are required to be<br>> >> irreversible connections to the ground bus in that disconnect, right?<br>> > <br>> > <br>> > <br>> > <br>> > <br>> > <br>> > _______________________________________________<br>> > List sponsored by Home Power magazine<br>> > <br>> > List Address: RE-wrenches@lists.re-wrenches.org<br>> > <br>> > Options & settings:<br>> > http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org<br>> > <br>> > List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org<br>> > <br>> > List rules & etiquette:<br>> > www.re-wrenches.org/etiquette.htm<br>> > <br>> > Check out participant bios:<br>> > www.members.re-wrenches.org<br>> > <br>> > <br>> _______________________________________________<br>> List sponsored by Home Power magazine<br>> <br>> List Address: RE-wrenches@lists.re-wrenches.org<br>> <br>> Options & settings:<br>> http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org<br>> <br>> List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org<br>> <br>> List rules & etiquette:<br>> www.re-wrenches.org/etiquette.htm<br>> <br>> Check out participant bios:<br>> www.members.re-wrenches.org<br>> <br>> </div></div></body></html>