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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif";color:black'>Ray and August:<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif";color:black'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif";color:black'>Thanks for the speedy reply. I did confuse M250s with the M215s. The actual inverters to be used are the M215s. <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif";color:black'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif";color:black'>I swear I had a spec sheet for the M190 that showed 0.75 A but I can’t find it anymore. So using 0.8A:<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif";color:black'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif";color:black'>9 * 0.8A = 7.2A<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif";color:black'>10 * .9A = 9.0A<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif";color:black'>Total = 16.2<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif";color:black'>De-rate: 16.2*1.25 = 20.25.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif";color:black'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif";color:black'>Maybe that will fly.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif";color:black'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif";color:black'>The other question is: I don’t have to use the value of the three breakers in the Solar load center to calculate my POC in the M/M/C? The code says: <i>The sum of the ampere ratings of overcurrent devices feeding a busbar or conductor shall not exceed 120% of the rating of the busbar or conductor. </i> I am assuming I don’t have to add the two 15s and the 20 and use that in figuring the back feed to the M/M/C since the M/MC is fed by a 20.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif";color:black'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif";color:black'>Thanks so much for your help. I am going to send this on to the lead inspector for the County. I am fortunate that he has always been willing to review these problems and flexible where appropriate, at least in my view.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif";color:black'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif";color:black'>Sincerely,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif";color:black'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif";color:black'>William Miller<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif";color:black'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif";color:black'>PS: I update the drawing.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif";color:black'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif";color:black'>Wm<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif";color:black'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif";color:black'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> re-wrenches-bounces@lists.re-wrenches.org [mailto:re-wrenches-bounces@lists.re-wrenches.org] <b>On Behalf Of </b>August Goers<br><b>Sent:</b> Wednesday, October 09, 2013 3:40 PM<br><b>To:</b> RE-wrenches<br><b>Subject:</b> Re: [RE-wrenches] Point of connection question<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><span style='color:#1F497D'>William,</span><o:p></o:p></p><p class=MsoNormal><span style='color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal><span style='color:#1F497D'>You have 9 M190s each running at 800 mA according to spec sheet. That equals 7.2 A nominal output current. Plus you have 10 M250s (if you look at your drawing) each running at 1 A = 10 A. 7.2 A + 10 A = 17.2 A * 1.25 = 21.5 A min breaker size. So, you'll need to round your breaker to a 25 A or 30 A breaker in the sub. You don't have any problem in the sub panel but the meter main is going to be a problem if it is a 100 A meter/main.</span><o:p></o:p></p><p class=MsoNormal><span style='color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal><span style='color:#1F497D'>Your drawing and case study notes don't seem to correspond - you mention M215s in the case study and show M250s on the drawing. If you indeed have 10 M215s then you're at 10 * 0.9 A = 9 A. 7.2 A + 9 A = 16.2 A * 1.25 = 20.25 A min breaker size. This is where it gets tricky. My fellow engineer just pointed out NEC 220.5(B) which allows you to drop fractions of amperes less than 0.5. So, I think you'd be okay with a 20 A solar breaker in this case.</span><o:p></o:p></p><p class=MsoNormal><span style='color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal><span style='color:#1F497D'>Best, August</span><o:p></o:p></p><p class=MsoNormal><span style='color:#1F497D'> </span><o:p></o:p></p><div><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> <a href="mailto:re-wrenches-bounces@lists.re-wrenches.org">re-wrenches-bounces@lists.re-wrenches.org</a> [mailto:<a href="mailto:re-wrenches-bounces@lists.re-wrenches.org">re-wrenches-bounces@lists.re-wrenches.org</a>] <b>On Behalf Of </b>William Miller<br><b>Sent:</b> Wednesday, October 09, 2013 3:07 PM<br><b>To:</b> RE-wrenches<br><b>Subject:</b> [RE-wrenches] Point of connection question</span><o:p></o:p></p></div></div><p class=MsoNormal> <o:p></o:p></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif"'>Friends:</span><o:p></o:p></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif"'> </span><o:p></o:p></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif"'>At the risk of asking a question that may have been asked and answered here in the past, I wish to pose a question about Point of Connection.</span><o:p></o:p></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif"'> </span><o:p></o:p></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif"'>Rather than outline the situation here I put it all on a web page. If any of you have a moment to review this, I would be most appreciative.</span><o:p></o:p></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif"'> </span><o:p></o:p></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif"'><a href="http://www.millersolar.com/MillerSolar/case_studies/POC/_POC_Question.html">http://www.millersolar.com/MillerSolar/case_studies/POC/_POC_Question.html</a></span><o:p></o:p></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif"'> </span><o:p></o:p></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif"'>Thanks in advance,</span><o:p></o:p></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif"'> </span><o:p></o:p></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif"'>William Miller</span><o:p></o:p></p><div class=MsoNormal align=center style='text-align:center'><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'><hr size=1 width="100%" noshade style='color:#A0A0A0' align=center></span></div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'>No virus found in this message.<br>Checked by AVG - <a href="http://www.avg.com">www.avg.com</a><br>Version: 2014.0.4142 / Virus Database: 3604/6722 - Release Date: 10/04/13<o:p></o:p></span></p></div></body></html>