<div dir="ltr"><div class="gmail_default" 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).</div>
<div class="gmail_default" style="font-family:verdana,sans-serif"><br></div><div class="gmail_default" style="font-family:verdana,sans-serif">The better code organization IMO would be:</div><div class="gmail_default" style="font-family:verdana,sans-serif">
<br></div><div class="gmail_default" style="font-family:verdana,sans-serif">705.12 (A) Allow supply side connections</div><div class="gmail_default" style="font-family:verdana,sans-serif">705.12 (B) Allow load side connections</div>
<div class="gmail_default" style="font-family:verdana,sans-serif">705.12 (C) Integrated Electrical Systems<br></div><div class="gmail_default" style="font-family:verdana,sans-serif">705.12 (D)(1)-(7) The requirements for all interconnection methods</div>
<div class="gmail_default" style="font-family:verdana,sans-serif">705.12 (E) Greater than 100kW</div><div class="gmail_default" style="font-family:verdana,sans-serif"><br></div><div class="gmail_default" style="font-family:verdana,sans-serif">
</div><div class="gmail_default" 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.</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:0px 0px 8px"><p style="margin:0px"><span><span>Jason Szumlanski</span></span></p>
<p style="margin:0px"></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=1403872191075&u=dedcb4cd140ce271" 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 Thu, Jun 26, 2014 at 6:11 PM, Corey Shalanski <span dir="ltr"><<a href="mailto:cshalanski@joule-energy.com" target="_blank">cshalanski@joule-energy.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex"><div dir="ltr"><div hspace="streak-pt-mark" style="max-height:1px">
<img style="width: 0px; max-height: 0px;" src="https://mailfoogae.appspot.com/t?sender=aY3NoYWxhbnNraUBqb3VsZS1lbmVyZ3kuY29t&type=zerocontent&guid=4710ea9a-f97d-435f-a3b5-0de6c0b1180d"><font color="#ffffff" size="1">ᐧ</font></div>
<div class="gmail_extra"><span style="font-family:arial,sans-serif;font-size:13px"><font color="#000000">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.</font></span><div style="font-family:arial,sans-serif;font-size:13px">
<font color="#000000"><br></font></div><div style="font-family:arial,sans-serif;font-size:13px"><font color="#000000">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"?</font></div>
<div style="font-family:arial,sans-serif;font-size:13px"><font color="#000000"><br></font></div><div style="font-family:arial,sans-serif;font-size:13px"><font color="#000000">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.</font></div>
<div>
<div style="font-family:arial,sans-serif;font-size:13px"><div><font color="#000000"><br></font></div><div><font color="#000000">--</font></div><div><font color="#000000">Corey Shalanski</font></div><div><font color="#000000">Joule Energy</font></div>
</div></div><div style="font-family:arial,sans-serif;font-size:13px"><font color="#000000">New Orleans, LA<br></font><div><div><font color="#000000"><img src="https://ssl.gstatic.com/ui/v1/icons/mail/images/cleardot.gif"></font></div>
</div><div><div class="gmail_extra"><font color="#000000"><br></font><div class="gmail_quote"><div><font color="#000000">On Thu, Jun 26, 2014 at 9:20 AM, <span dir="ltr"><<a href="mailto:re-wrenches-request@lists.re-wrenches.org" target="_blank">re-wrenches-request@lists.re-wrenches.org</a>></span> wrote:<br>
</font></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex"><font color="#000000"><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>><div><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:<br></div> <<a href="mailto:CAJJtG3oQGBLzatinUHFp_GhivzYD6dLdsLAnkc1ofG9tR1RFgA@mail.gmail.com" target="_blank">CAJJtG3oQGBLzatinUHFp_GhivzYD6dLdsLAnkc1ofG9tR1RFgA@mail.gmail.com</a>><br>
Content-Type: text/plain; charset="utf-8"<div><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.<br><br></div>?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<div><br>sized/rated for the entire maximum string.<br>
<br>Jason Szumlanski<br><br></div></font></blockquote></div></div></div></div></div></div></blockquote></div></div></div>