<div dir="ltr"><div class="gmail_default" style="font-family:verdana,sans-serif">Bill,</div><div class="gmail_default" style="font-family:verdana,sans-serif"><br></div><div class="gmail_default" style="font-family:verdana,sans-serif">
I would be happy to contribute.</div><div class="gmail_default" style="font-family:verdana,sans-serif"><br></div><div class="gmail_default" style="font-family:verdana,sans-serif">Regarding the 120% rule, I'm not sure I agree. There can be panelboards connected in series in a supply side connection, and there can be loads in PV inverter aggregation panels used in supply-side connections. For example, it is common to install a dedicated outlet circuit for monitoring gateways in microinverter system aggregation panels.</div>
<div class="gmail_default" style="font-family:verdana,sans-serif"><br></div><div class="gmail_default" style="font-family:verdana,sans-serif">This below is compliant, and would have the same need for the 120% rule as a load side connection if I understand the rationale correctly (notwithstanding the way each code cycle is organized):</div>
<div class="gmail_default" style="font-family:verdana,sans-serif"><br></div><div class="gmail_default" style="font-family:verdana,sans-serif">Supply<-->Fusible Disconnect<-->Aggregation Panel<-->Sub-Aggregation Panels<-->PV Inverters and Loads</div>
<div><br></div><div><br></div><div class="gmail_default" style="font-family:verdana,sans-serif">I'm not up to speed on the 2014 changes, so I'm really just talking about the changes from 2008 to 2011, which seem to have moved in the direction of applying 705.12(D)(1)-(7) to both load- and supply-side interconnected systems in 2011, whereas 690.64(B)(1)-(7) in 2008 clearly applied to load-side connections only.</div>
<div class="gmail_default" style="font-family:verdana,sans-serif"><br></div><div class="gmail_default" style="font-family:verdana,sans-serif">Are you saying 705.12(D)(1)-(7) in 2011 apply to load-side connections only? That's not the way I interpret it. </div>
<br><br><div id="WISESTAMP_SIG_gmail_session" href="http://WISESTAMP_SIG_gmail_session"><div style="font-size:13px;font-family:Verdana,Arial,Helvetica,sans-serif"><div style="margin:0 0 8px 0"><p style="margin:0"><span><span>Jason Szumlanski</span></span></p>
<p style="margin:0"></p><div class="gmail_default" style="font-family:verdana,sans-serif;display:inline">Fafco Solar</div><br> <p></p><div style="clear:both"></div></div><img src="https://wisestamp.appspot.com/pixview.gif?p=chrome&v=3.42.0&t=1404154583977&u=d0c775731865b324" width="1" height="1"></div>
<img src="http://ws-stats.appspot.com/ga/pixel.png?yes__count=true&e=legacy_impression"></div><div class="gmail_extra"><br><br><div class="gmail_quote">On Fri, Jun 27, 2014 at 8:12 PM, Bill Brooks <span dir="ltr"><<a href="mailto:billbrooks7@yahoo.com" target="_blank">billbrooks7@yahoo.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div lang="EN-US" link="blue" vlink="purple"><div><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">Jason,<u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d"><u></u> <u></u></span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">It sounds like you want to get involved with the PV industry forum. We have about 30+ active members this year so your input would be welcome.<u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d"><u></u> <u></u></span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">I think your idea about organization needs to be informed about some details. First of all, you need to read the new, very different, 705.12(D). SolarPro has a nice article about code updates.<u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d"><u></u> <u></u></span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">Secondly, rules on the supply side are very different than load side. Supply side connections, by definition have no loads connected to them. It is simpler and does not need any 120% rule. The 120% rule is a very conservative restriction. No such restriction exists on the supply side.<u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d"><u></u> <u></u></span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">Too much to cover all the issues now—suffice it to say there are many, many reasons to keep supply-side and load-side connections separate.<u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d"><u></u> <u></u></span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">Bill.<u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d"><u></u> <u></u></span></p><p class="MsoNormal"><b><span style="font-size:11.0pt;font-family:"Calibri","sans-serif"">From:</span></b><span style="font-size:11.0pt;font-family:"Calibri","sans-serif""> RE-wrenches [mailto:<a href="mailto:re-wrenches-bounces@lists.re-wrenches.org" target="_blank">re-wrenches-bounces@lists.re-wrenches.org</a>] <b>On Behalf Of </b>Jason Szumlanski<br>
<b>Sent:</b> Friday, June 27, 2014 5:45 AM<br><b>To:</b> RE-wrenches</span></p><div class=""><br><b>Subject:</b> Re: [RE-wrenches] Combining Multiple Inverters<u></u><u></u></div><p></p><p class="MsoNormal"><u></u> <u></u></p>
<div><div><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif"">It depends on your applicable code. In the 2008 code, 690.64(B) was specifically titled "Load Side" and the provisions of that section in full were not applicable to supply side connections. That was probably not the intention (i.e. the 120% rule and OCPD requirements should have applied to aggregation panels). In the 2011 code, 705.12(D) is the similar section, but it has been titled "Utility Interactive Inverters." This section now "allows" load side connections, but the requirements (1) through (7) of this section still apply to supply side connections (my interpretation).<u></u><u></u></span></p>
</div><div><div class="h5"><div><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif""><u></u> <u></u></span></p></div><div><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif"">The better code organization IMO would be:<u></u><u></u></span></p>
</div><div><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif""><u></u> <u></u></span></p></div><div><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif"">705.12 (A) Allow supply side connections<u></u><u></u></span></p>
</div><div><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif"">705.12 (B) Allow load side connections<u></u><u></u></span></p></div><div><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif"">705.12 (C) Integrated Electrical Systems<u></u><u></u></span></p>
</div><div><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif"">705.12 (D)(1)-(7) The requirements for all interconnection methods<u></u><u></u></span></p></div><div><p class="MsoNormal">
<span style="font-family:"Verdana","sans-serif"">705.12 (E) Greater than 100kW<u></u><u></u></span></p></div><div><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif""><u></u> <u></u></span></p>
</div><div><p class="MsoNormal"><span style="font-family:"Arial","sans-serif""></span><span style="font-family:"Verdana","sans-serif""><u></u><u></u></span></p></div><div><p class="MsoNormal">
<span style="font-family:"Verdana","sans-serif"">A bit off-topic, but we recently had a utility reject a plan to install a 320A meter socket with a 200A main distribution panel and a 100A solar aggregation panel (with four 20A backfed breakers). The two panels were to be fed from double lugs in the meter can. They said this was not allowed - they didn't want solar in their meter can. When I pointed out that dual 200A load panels are commonly fed this way and this was no different because I could just backfeed each 200A panel with two 20A breakers, my comment was met with blank stares.<u></u><u></u></span></p>
</div><p class="MsoNormal" style="margin-bottom:12.0pt"><u></u> <u></u></p><div><div><div style="margin-bottom:6.0pt"><p style="margin:0in;margin-bottom:.0001pt"><span style="font-size:10.0pt;font-family:"Verdana","sans-serif"">Jason Szumlanski<u></u><u></u></span></p>
<div><p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif""></span><span style="font-size:10.0pt;font-family:"Verdana","sans-serif"">Fafco Solar</span><span style="font-size:10.0pt;font-family:"Arial","sans-serif""></span><span style="font-size:10.0pt;font-family:"Verdana","sans-serif""><u></u><u></u></span></p>
</div><p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Verdana","sans-serif""><br> <u></u><u></u></span></p></div><p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Verdana","sans-serif""><img width="1" height="1" src="https://wisestamp.appspot.com/pixview.gif?p=chrome&v=3.42.0&t=1403872191075&u=dedcb4cd140ce271"><u></u><u></u></span></p>
</div><p class="MsoNormal"><img src="http://ws-stats.appspot.com/ga/pixel.png?yes__count=true%20&e=legacy_impression"><u></u><u></u></p></div><div><p class="MsoNormal" style="margin-bottom:12.0pt"><u></u> <u></u></p>
<div>
<p class="MsoNormal">On Thu, Jun 26, 2014 at 6:11 PM, Corey Shalanski <<a href="mailto:cshalanski@joule-energy.com" target="_blank">cshalanski@joule-energy.com</a>> wrote:<u></u><u></u></p><blockquote style="border:none;border-left:solid #cccccc 1.0pt;padding:0in 0in 0in 6.0pt;margin-left:4.8pt;margin-right:0in">
<div><div><p class="MsoNormal"><img border="0" src="https://mailfoogae.appspot.com/t?sender=aY3NoYWxhbnNraUBqb3VsZS1lbmVyZ3kuY29t&type=zerocontent&guid=4710ea9a-f97d-435f-a3b5-0de6c0b1180d"><span style="font-size:7.5pt;font-family:"Gadugi","sans-serif";color:white">ᐧ</span><u></u><u></u></p>
</div><div><p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:black">Perhaps I should've been more specific with my scenario. I was imagining a supply side connection, as this would more commonly be the case when combining multiple inverters. In this case it seems like the provisions of 705.12(D) for load side conections don't even apply, no? Rather 705.12(A) becomes the relevant section, and I see very few restrictions there.</span><u></u><u></u></p>
<div><p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif""><u></u> <u></u></span></p></div><div><p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:black">Even with a load side connection I would tend to agree with Jason's interpretation: Does the "source interconnection" in 705.12(D)(1) refer to each individual inverter, or can it refer to an aggregated "source"?</span><span style="font-size:10.0pt;font-family:"Arial","sans-serif""><u></u><u></u></span></p>
</div><div><p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif""><u></u> <u></u></span></p></div><div><p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:black">I am interested in pursuing this idea, mainly to understand how/where the NEC forbids it. In lieu of a clear Code reference against it, how is this any different from a branch circuit (in reverse)? ie, as with microinverters.</span><span style="font-size:10.0pt;font-family:"Arial","sans-serif""><u></u><u></u></span></p>
</div><div><div><div><p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif""><u></u> <u></u></span></p></div><div><p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:black">--</span><span style="font-size:10.0pt;font-family:"Arial","sans-serif""><u></u><u></u></span></p>
</div><div><p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:black">Corey Shalanski</span><span style="font-size:10.0pt;font-family:"Arial","sans-serif""><u></u><u></u></span></p>
</div><div><p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:black">Joule Energy</span><span style="font-size:10.0pt;font-family:"Arial","sans-serif""><u></u><u></u></span></p>
</div></div></div><div><p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:black">New Orleans, LA</span><span style="font-size:10.0pt;font-family:"Arial","sans-serif""><u></u><u></u></span></p>
<div><div><p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:black"><img border="0" src="https://ssl.gstatic.com/ui/v1/icons/mail/images/cleardot.gif"></span><span style="font-size:10.0pt;font-family:"Arial","sans-serif""><u></u><u></u></span></p>
</div></div><div><div><p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif""><u></u> <u></u></span></p><div><div><p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:black">On Thu, Jun 26, 2014 at 9:20 AM, <<a href="mailto:re-wrenches-request@lists.re-wrenches.org" target="_blank">re-wrenches-request@lists.re-wrenches.org</a>> wrote:</span><span style="font-size:10.0pt;font-family:"Arial","sans-serif""><u></u><u></u></span></p>
</div><blockquote style="border:none;border-left:solid #cccccc 1.0pt;padding:0in 0in 0in 6.0pt;margin-left:4.8pt;margin-right:0in"><p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:black"><br>
Message: 11<br>Date: Thu, 26 Jun 2014 09:10:07 -0400<br>From: Jason Szumlanski <<a href="mailto:jason@fafcosolar.com" target="_blank">jason@fafcosolar.com</a>><u></u><u></u></span></p><div><p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:black"><br>
To: RE-wrenches <<a href="mailto:re-wrenches@lists.re-wrenches.org" target="_blank">re-wrenches@lists.re-wrenches.org</a>><br>Subject: Re: [RE-wrenches] Combining Multiple Inverters<br>Message-ID:<u></u><u></u></span></p>
</div><p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:black"> <<a href="mailto:CAJJtG3oQGBLzatinUHFp_GhivzYD6dLdsLAnkc1ofG9tR1RFgA@mail.gmail.com" target="_blank">CAJJtG3oQGBLzatinUHFp_GhivzYD6dLdsLAnkc1ofG9tR1RFgA@mail.gmail.com</a>><br>
Content-Type: text/plain; charset="utf-8"<u></u><u></u></span></p><div><p class="MsoNormal" style="margin-bottom:12.0pt"><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:black"><br>
<br>705.12(D) reads, "... the interconnection provisions for the<br>utility-interactive inverter(s) shall comply with (D)(1) through (D)(7)."<br>That's inverters - plural. The interconnection must be protected by<br>
dedicated OCPD, not each inverter individually. Microinverters comply<br>because of this interpretation.<br><br>That said, I've never done it. An accumulator panel is pretty cost<br>effective when you consider the alternative cost of an enclosure and the<br>
Polaris connectors. I guess if you are making the Polaris connections<br>inside the main load center or inside an inverter you can eliminate the<br>cost of a dedicated enclosure. There would be some material and labor<br>
savings.<u></u><u></u></span></p></div><p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:black">?If the inverter has a maximum OCPD rating, you will be limited by that.<br>
?Microinverters "get around" that by the wire and inverter being<u></u><u></u></span></p><div><p class="MsoNormal" style="margin-bottom:12.0pt"><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:black"><br>
sized/rated for the entire maximum string.<br><br>Jason Szumlanski<u></u><u></u></span></p></div></blockquote></div></div></div></div></div></div></blockquote></div></div></div></div></div></div>
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