<html><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8"><meta name="Generator" content="Microsoft Word 14 (filtered medium)"><style><!--
/* Font Definitions */
@font-face
{font-family:Helvetica;
panose-1:2 11 6 4 2 2 2 2 2 4;}
@font-face
{font-family:Helvetica;
panose-1:2 11 6 4 2 2 2 2 2 4;}
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
@font-face
{font-family:Tahoma;
panose-1:2 11 6 4 3 5 4 4 2 4;}
@font-face
{font-family:Verdana;
panose-1:2 11 6 4 3 5 4 4 2 4;}
@font-face
{font-family:Consolas;
panose-1:2 11 6 9 2 2 4 3 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0in;
margin-bottom:.0001pt;
font-size:12.0pt;
font-family:"Times New Roman","serif";
color:black;}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:blue;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{mso-style-priority:99;
color:purple;
text-decoration:underline;}
p
{mso-style-priority:99;
mso-margin-top-alt:auto;
margin-right:0in;
mso-margin-bottom-alt:auto;
margin-left:0in;
font-size:12.0pt;
font-family:"Times New Roman","serif";
color:black;}
pre
{mso-style-priority:99;
mso-style-link:"HTML Preformatted Char";
margin:0in;
margin-bottom:.0001pt;
font-size:10.0pt;
font-family:"Courier New";
color:black;}
span.apple-converted-space
{mso-style-name:apple-converted-space;}
span.HTMLPreformattedChar
{mso-style-name:"HTML Preformatted Char";
mso-style-priority:99;
mso-style-link:"HTML Preformatted";
font-family:"Consolas","serif";
color:black;}
span.EmailStyle21
{mso-style-type:personal-reply;
font-family:"Verdana","sans-serif";
color:#1F497D;}
.MsoChpDefault
{mso-style-type:export-only;
font-size:10.0pt;}
@page WordSection1
{size:8.5in 11.0in;
margin:1.0in 1.0in 1.0in 1.0in;}
div.WordSection1
{page:WordSection1;}
--></style></head><body bgcolor="white" lang="EN-US" link="blue" vlink="purple"><div class="WordSection1"><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1f497d">Chris:</span></p><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1f497d"> </span></p><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1f497d">The 2014 code would require individual disconnecting means prior to aggregation, i.e. an AC combiner. Therefore your scenario would not exist.</span></p><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1f497d"> </span></p><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1f497d">Wm</span></p><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1f497d"> </span></p><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1f497d"> </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";color:windowtext">From:</span></b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";color:windowtext"> RE-wrenches [mailto:<a href="mailto:re-wrenches-bounces@lists.re-wrenches.org">re-wrenches-bounces@lists.re-wrenches.org</a>] <b>On Behalf Of </b>Christopher Warfel<br><b>Sent:</b> Wednesday, February 27, 2019 10:43 AM<br><b>To:</b> <a href="mailto:re-wrenches@lists.re-wrenches.org">re-wrenches@lists.re-wrenches.org</a><br><b>Subject:</b> Re: [RE-wrenches] Multiple inverters</span></p></div></div><p class="MsoNormal"> </p><p>I know I keep popping up on this, but 2014 makes no sense if it is saying to connect multiple inverters to one disconnect. It would be difficult and dangerous to take one out of service for any reason including replacement. I would that that you'd have to shut down all the inverters just to replace one. Some of the large commercial/industrial/utility systems have hundreds of inverters and there is no way they would install a system to this interpretation of the NEC.</p><div><p class="MsoNormal">On 2/27/2019 12:22 PM, Starlight Solar Power Systems wrote:</p></div><blockquote style="margin-top:5.0pt;margin-bottom:5.0pt"><p class="MsoNormal">William, </p><div><p class="MsoNormal"> </p></div><div><p class="MsoNormal">It seems this question needs to be addressed: What is the intended meaning of \u201cinstalled in one system\u201d in 2014? If you have separate \u201csystems\u201d, they should not be governed by 705.12. So, at what point does a \u201csystem\u201d begin and end? PV modules to the disconnect? ...to the load panel? ...to the service entrance?</p></div><div><p class="MsoNormal"> </p></div><div><p class="MsoNormal">Larry</p><div><p class="MsoNormal"> </p></div><p class="MsoNormal"> </p><div><div><p class="MsoNormal">On Feb 25, 2019, at 10:42 PM, William Miller <<a href="mailto:william@millersolar.com">william@millersolar.com</a>> wrote:</p></div><p class="MsoNormal"> </p><div><div><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1f497d">August:</span></p></div><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1f497d"> </span></p><div><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1f497d">The 2014 code, which the AHJ for this project is using, states the following:</span></p></div><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1f497d"> </span></p><div><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1f497d">(<i>1) Dedicated Overcurrent and Disconnect. The source</i></span></p></div><div><p class="MsoNormal"><i><span style="font-family:"Verdana","sans-serif";color:#1f497d">interconnection of one or more inverters installed in one</span></i></p></div><div><p class="MsoNormal"><i><span style="font-family:"Verdana","sans-serif";color:#1f497d">system shall be made at a dedicated circuit breaker or fusible</span></i></p></div><div><p class="MsoNormal"><i><span style="font-family:"Verdana","sans-serif";color:#1f497d">disconnecting means.</span></i></p></div><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1f497d"> </span></p><div><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1f497d">Note that the language says, \u201cThe source interconnection\u2026\u201d (singular), and \u201cat a dedicated circuit breaker\u2026\u201d(again singular). This makes it obvious to me that the language says that the outputs of multiple inverters need to be aggregated and connected via<span class="apple-converted-space"> </span><u>one</u><span class="apple-converted-space"> </span>OCPD. I think the other wrenches missed this point.</span></p></div><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1f497d"> </span></p><div><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1f497d">Your input is valuable by contrasting the language of the 2014 code with that of the 2017 version. The inclusion of the phrase \u201cEach source\u2026\u201d in the 2017 code completely changes the meaning. Some AHJs will look to future code versions for clarity even if they are not yet adopted. I think this is a good thing, and I really appreciate you bringing up the new language.</span></p></div><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1f497d"> </span></p><div><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1f497d">The article from AEIA magazine ratifies the conclusion I drew from the 2014 code. Fortunately the AHJ is misinterpreting the section to allow the more liberal interpretation, the one that the 2017 code reflects. I find it best to contact the plan checker directly, which I did, and we are approved for multiple OCPDs. By the way, I think that article is well written and I have book marked it.</span></p></div><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1f497d"> </span></p><div><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1f497d">I don\u2019t know if the 2014 language was a mistake corrected in 2107, or what the thinking was of the authors. Regardless, we live by the language, not the intent.</span></p></div><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1f497d"> </span></p><div><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1f497d">Thank you as well to all who responded.</span></p></div><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1f497d"> </span></p><div><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1f497d">William Miller</span></p></div><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1f497d"> </span></p><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1f497d"> </span></p><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1f497d"> </span></p><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1f497d"> </span></p><div><p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">From:</span></b><span class="apple-converted-space"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif""> </span></span><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">August Goers [mailto:<a href="mailto:august@luminalt.com"><span style="color:purple">august@luminalt.com</span></a>]<span class="apple-converted-space"> </span><br><b>Sent:</b><span class="apple-converted-space"> </span>Monday, February 25, 2019 9:07 AM<br><b>To:</b><span class="apple-converted-space"> </span>William Miller; RE-wrenches<br><b>Subject:</b><span class="apple-converted-space"> </span>Re: [RE-wrenches] Multiple inverters</span></p></div><p class="MsoNormal"> </p><div><div><p class="MsoNormal">Hi William - </p></div><div><p class="MsoNormal"> </p></div><div><div><p class="MsoNormal">In this case, it is helpful to look forward to the 2017 NEC for guidance:</p></div></div><div><p class="MsoNormal"> </p></div><div><div><div><p class="MsoNormal"><image001.png></p></div></div><div><p class="MsoNormal"> </p></div><div><div><p class="MsoNormal">I believe it's perfectly fine to have multiple inverter breakers in your main.</p></div></div><div><p class="MsoNormal"> </p></div><div><div><p class="MsoNormal">August</p></div></div><div><div><p class="MsoNormal">Luminalt</p></div></div><p class="MsoNormal"> </p></div></div><p class="MsoNormal"> </p><div><div><div><p class="MsoNormal">On Mon, Feb 25, 2019 at 8:42 AM William Miller <<a href="mailto:william@millersolar.com"><span style="color:purple">william@millersolar.com</span></a>> wrote:</p></div></div><blockquote style="border:none;border-left:solid #cccccc 1.0pt;padding:0in 0in 0in 6.0pt;margin-left:4.8pt;margin-top:5.0pt;margin-right:0in;margin-bottom:5.0pt"><div><div><div><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif"">Friends:</span></p></div><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif""> </span></p><div><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif"">I have an NEC code question on an upcoming project. It is a home that has an existing 8 kW ground-mounted grid-tied system. The owner wants to add another 10 kW of grid-tied PV. My question is about 705.12, point of connection. Specifically section (D)(1). That section states:<span class="apple-converted-space"> </span></span></p></div><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif""> </span></p><div><p class="MsoNormal"><i><span style="font-family:"Verdana","sans-serif"">The source interconnection of one or more inverters installed in one system shall be made at a dedicated circuit breaker or fusible disconnecting means.</span></i></p></div><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif""> </span></p><div><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif"">So if there are going to be two inverters on premise, do the outputs have to be aggregated to connect via one circuit breaker? This might be difficult to do as the exiting inverter is connected via a different sub-panel than the one that is planned to receive the new inverter output.</span></p></div><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif""> </span></p><div><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif"">This<span class="apple-converted-space"> </span><a href="https://iaeimagazine.org/magazine/2014/01/16/load-side-pv-connections/" target="_blank"><span style="color:purple">article</span></a><span class="apple-converted-space"> </span>addresses the question.</span></p></div><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif""> </span></p><div><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif"">I would be very grateful if any of you can share any experience you might have in interpreting this section of the code.</span></p></div><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif""> </span></p><div><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif"">Thanks in advance.</span></p></div><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif""> </span></p><div><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif"">William</span></p></div><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif""> </span></p></div></div><p class="MsoNormal" style="margin-bottom:12.0pt">_______________________________________________<br>List sponsored by Redwood Alliance<br><br>List Address:<span class="apple-converted-space"> </span><a href="mailto:RE-wrenches@lists.re-wrenches.org" target="_blank"><span style="color:purple">RE-wrenches@lists.re-wrenches.org</span></a><br><br>Change listserver email address & settings:<br><a href="http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org" target="_blank"><span style="color:purple">http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org</span></a><br><br>List-Archive:<span class="apple-converted-space"> </span><a href="http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html" target="_blank"><span style="color:purple">http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html</span></a><br><br>List rules & etiquette:<br><a href="http://www.re-wrenches.org/etiquette.htm" target="_blank"><span style="color:purple">www.re-wrenches.org/etiquette.htm</span></a><br><br>Check out or update participant bios:<br><a href="http://www.members.re-wrenches.org/" target="_blank"><span style="color:purple">www.members.re-wrenches.org</span></a></p></blockquote></div><p class="MsoNormal"><span style="font-size:10.5pt;font-family:"Helvetica","sans-serif"">_______________________________________________<br>List sponsored by Redwood Alliance<br><br>List Address:<span class="apple-converted-space"> </span></span><a href="mailto:RE-wrenches@lists.re-wrenches.org"><span style="font-size:10.5pt;font-family:"Helvetica","sans-serif";color:purple">RE-wrenches@lists.re-wrenches.org</span></a><span style="font-size:10.5pt;font-family:"Helvetica","sans-serif""><br><br>Change listserver email address & settings:<br></span><a href="http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org"><span style="font-size:10.5pt;font-family:"Helvetica","sans-serif";color:purple">http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org</span></a><span style="font-size:10.5pt;font-family:"Helvetica","sans-serif""><br><br>List-Archive:<span class="apple-converted-space"> </span></span><a href="http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html"><span style="font-size:10.5pt;font-family:"Helvetica","sans-serif";color:purple">http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html</span></a><span style="font-size:10.5pt;font-family:"Helvetica","sans-serif""><br><br>List rules & etiquette:<br></span><a href="http://www.re-wrenches.org/etiquette.htm"><span style="font-size:10.5pt;font-family:"Helvetica","sans-serif";color:purple">www.re-wrenches.org/etiquette.htm</span></a><span style="font-size:10.5pt;font-family:"Helvetica","sans-serif""><br><br>Check out or update participant bios:<br></span><a href="http://www.members.re-wrenches.org/"><span style="font-size:10.5pt;font-family:"Helvetica","sans-serif";color:purple">www.members.re-wrenches.org</span></a></p></div></div><p class="MsoNormal"> </p></div><p class="MsoNormal"><br><br></p><pre>_______________________________________________</pre><pre>List sponsored by Redwood Alliance</pre><pre> </pre><pre>List Address: <a href="mailto:RE-wrenches@lists.re-wrenches.org">RE-wrenches@lists.re-wrenches.org</a></pre><pre> </pre><pre>Change listserver email address & settings:</pre><pre><a 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></pre><pre> </pre><pre>List-Archive: <a href="http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html">http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html</a></pre><pre> </pre><pre>List rules & etiquette:</pre><pre><a href="http://www.re-wrenches.org/etiquette.htm">www.re-wrenches.org/etiquette.htm</a></pre><pre> </pre><pre>Check out or update participant bios:</pre><pre><a href="http://www.members.re-wrenches.org">www.members.re-wrenches.org</a></pre><pre> </pre></blockquote></div></body></html>