<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"></head><body dir="auto"><div>Even in a feeder with line-neutral loads, the neutral still only carries the imbalance between the phase loads: the case of maximum possible neutral current is the hypothetical situation of the phase with largest line-neutral load current, with all those loads on, and both other phases having all line-neutral loads off---in order to get neutral current, you have to reduce the phase current in two legs--- </div><div>So normally in 4-wire star feeders, you only need to rate for 3 current carrying conductors. </div><div><br></div><div>If the neutral conductor connects to a solar inverter, the neutral load is either zero (3 phase inverter) or non-additive if you have a bank of 1 phase line/neutral (120 or 277 volt) inverters <br><br>/wk<div><br></div><div>William Korthof</div><div>714.875.3576</div><div>Sustainable Solutions</div><div>#956904</div></div><div><br>On Mar 4, 2014, at 1:31 PM, Allen Frishman <<a href="mailto:amfrish@aeonsolar.com">amfrish@aeonsolar.com</a>> wrote:<br><br></div><div><base href="x-msg://248/">what inverter(s) are you using? In many cases the Neutral is not considered a Current Carying Conductor by the Manufacturer and therefore you only have 3 CCC.<br><div>
<span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; font-size: medium; "><div><p class="MsoNormal"><i><span style="font-size: 10.5pt; color: black; ">Al Frishman</span></i><span style="font-size: 13.5pt; color: black; "><br></span><span style="font-size: 13.5pt; color: rgb(3, 1, 0); ">Aeon</span><span style="font-size: 13.5pt; color: rgb(255, 151, 0); ">Solar</span><span style="font-size: 13.5pt; color: black; "></span></p><p class="MsoNormal"><i><span style="font-size: 10.5pt; color: black; "><a href="tel:%28917%29%20699-6641" value="+19176996641" target="_blank">(917) 699-6641</a> - cell</span></i><span style="font-size: 10.5pt; color: black; "><br></span><i><span style="font-size: 10.5pt; color: black; "><a href="tel:%28888%29%20460-2867" value="+18884602867" target="_blank">(888) 460-2867</a></span></i><span style="font-size: 10.5pt; color: black; "><br></span><i><span style="font-size: 10.5pt; color: black; "><a href="http://www.aeonsolar.com/" target="_blank">www.aeonsolar.com</a></span></i></p></div></span>
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<br><div><div>On Mar 4, 2014, at 4:20 PM, Kirk Herander wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><span class="Apple-style-span" style="border-collapse: separate; font-family: Helvetica; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; font-size: medium; "><div bgcolor="white" lang="EN-US" link="blue" vlink="purple"><div class="WordSection1" style="page: WordSection1; "><div style="margin-right: 0in; margin-left: 0in; font-size: 12pt; font-family: 'Times New Roman', serif; color: black; margin-top: 0in; margin-bottom: 0.0001pt; "><span style="font-size: 14pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125); ">Approx.. 50 – 60ft.<o:p></o:p></span></div><div style="margin-right: 0in; margin-left: 0in; font-size: 12pt; font-family: 'Times New Roman', serif; color: black; margin-top: 0in; margin-bottom: 0.0001pt; "><span style="font-size: 14pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125); "><o:p> </o:p></span></div><div><div style="margin-right: 0in; margin-left: 0in; font-size: 12pt; font-family: 'Times New Roman', serif; color: black; margin-top: 0in; margin-bottom: 0.0001pt; "><span style="font-size: 14pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125); ">Kirk Herander<o:p></o:p></span></div><div style="margin-right: 0in; margin-left: 0in; font-size: 12pt; font-family: 'Times New Roman', serif; color: black; margin-top: 0in; margin-bottom: 0.0001pt; "><span style="font-size: 14pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125); ">VT Solar, LLC<o:p></o:p></span></div><div style="margin-right: 0in; margin-left: 0in; font-size: 12pt; font-family: 'Times New Roman', serif; color: black; margin-top: 0in; margin-bottom: 0.0001pt; "><span style="font-size: 14pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125); ">dba Vermont Solar Engineering<o:p></o:p></span></div><div style="margin-right: 0in; margin-left: 0in; font-size: 12pt; font-family: 'Times New Roman', serif; color: black; margin-top: 0in; margin-bottom: 0.0001pt; "><span style="font-size: 14pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125); ">NABCEP<sup>TM<span class="Apple-converted-space"> </span></sup>Certified Inaugural Certificant<o:p></o:p></span></div><div style="margin-right: 0in; margin-left: 0in; font-size: 12pt; font-family: 'Times New Roman', serif; color: black; margin-top: 0in; margin-bottom: 0.0001pt; "><span style="font-size: 14pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125); ">NYSERDA-eligible Installer<o:p></o:p></span></div><div style="margin-right: 0in; margin-left: 0in; font-size: 12pt; font-family: 'Times New Roman', serif; color: black; margin-top: 0in; margin-bottom: 0.0001pt; "><span style="font-size: 14pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125); ">VT RE Incentive Program Partner<o:p></o:p></span></div><div style="margin-right: 0in; margin-left: 0in; font-size: 12pt; font-family: 'Times New Roman', serif; color: black; margin-top: 0in; margin-bottom: 0.0001pt; "><span style="font-size: 14pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125); ">802.863.1202<o:p></o:p></span></div></div><div style="margin-right: 0in; margin-left: 0in; font-size: 12pt; font-family: 'Times New Roman', serif; color: black; margin-top: 0in; margin-bottom: 0.0001pt; "><span style="font-size: 14pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125); "><o:p> </o:p></span></div><div><div style="border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-top-style: solid; border-top-color: rgb(181, 196, 223); border-top-width: 1pt; padding-top: 3pt; padding-right: 0in; padding-bottom: 0in; padding-left: 0in; "><div style="margin-right: 0in; margin-left: 0in; font-size: 12pt; font-family: 'Times New Roman', serif; color: black; margin-top: 0in; margin-bottom: 0.0001pt; "><b><span style="font-size: 10pt; font-family: Tahoma, sans-serif; color: windowtext; ">From:</span></b><span style="font-size: 10pt; font-family: Tahoma, sans-serif; color: windowtext; "><span class="Apple-converted-space"> </span><a href="mailto:re-wrenches-bounces@lists.re-wrenches.org" style="color: blue; text-decoration: underline; ">re-wrenches-bounces@lists.re-wrenches.org</a><span class="Apple-converted-space"> </span>[<a href="mailto:re-wrenches-bounces@lists.re-wrenches.org">mailto:re-wrenches-bounces@lists.re-wrenches.org</a>]<span class="Apple-converted-space"> </span><b>On Behalf Of<span class="Apple-converted-space"> </span></b>Ray Walters<br><b>Sent:</b><span class="Apple-converted-space"> </span>Tuesday, March 04, 2014 4:05 PM<br><b>To:</b><span class="Apple-converted-space"> </span>RE-wrenches<br><b>Subject:</b><span class="Apple-converted-space"> </span>Re: [RE-wrenches] conductors and the 120% rule<o:p></o:p></span></div></div></div><div style="margin-right: 0in; margin-left: 0in; font-size: 12pt; font-family: 'Times New Roman', serif; color: black; margin-top: 0in; margin-bottom: 0.0001pt; "><o:p> </o:p></div><div><div style="margin-right: 0in; margin-left: 0in; font-size: 12pt; font-family: 'Times New Roman', serif; color: black; margin-top: 0in; margin-bottom: 0.0001pt; ">What is the length of the conduit to the subpanel? That will determine whether to apply the derates.<br><br><o:p></o:p></div><pre style="margin-top: 0in; margin-right: 0in; margin-left: 0in; margin-bottom: 0.0001pt; font-size: 10pt; font-family: 'Courier New'; color: black; ">R.Ray Walters<o:p></o:p></pre><pre style="margin-top: 0in; margin-right: 0in; margin-left: 0in; margin-bottom: 0.0001pt; font-size: 10pt; font-family: 'Courier New'; color: black; ">CTO, Solarray, Inc<o:p></o:p></pre><pre style="margin-top: 0in; margin-right: 0in; margin-left: 0in; margin-bottom: 0.0001pt; font-size: 10pt; font-family: 'Courier New'; color: black; ">Nabcep Certified PV Installer, <o:p></o:p></pre><pre style="margin-top: 0in; margin-right: 0in; margin-left: 0in; margin-bottom: 0.0001pt; font-size: 10pt; font-family: 'Courier New'; color: black; ">Licensed Master Electrician<o:p></o:p></pre><pre style="margin-top: 0in; margin-right: 0in; margin-left: 0in; margin-bottom: 0.0001pt; font-size: 10pt; font-family: 'Courier New'; color: black; ">Solar Design Engineer<o:p></o:p></pre><pre style="margin-top: 0in; margin-right: 0in; margin-left: 0in; margin-bottom: 0.0001pt; font-size: 10pt; font-family: 'Courier New'; color: black; ">303 505-8760<o:p></o:p></pre><div style="margin-right: 0in; margin-left: 0in; font-size: 12pt; font-family: 'Times New Roman', serif; color: black; margin-top: 0in; margin-bottom: 0.0001pt; ">On 3/4/2014 1:34 PM, Kirk Herander wrote:<o:p></o:p></div></div><blockquote style="margin-top: 5pt; margin-bottom: 5pt; "><div style="margin-right: 0in; margin-left: 0in; font-size: 12pt; font-family: 'Times New Roman', serif; color: black; margin-top: 0in; margin-bottom: 0.0001pt; "><span style="font-size: 14pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125); ">Whether or not a further derate has to be applied is the killer here, as I am working with existing panels and conductors. In an old Code Corner(HP140) J. Wiles goes through a similar scenario and calls out the allowable current rating and conductor in 310.15, but makes no mention of applying additional derate factors. The .8 derate for 4-6 conductors(l1,l2,l3, & n) will put the existing 4/0 cable between feed-in and main panel at 208 amps, less than the allowable 217. I’d hate to need to upsize the wire to 250 mcm.</span><o:p></o:p></div><div style="margin-right: 0in; margin-left: 0in; font-size: 12pt; font-family: 'Times New Roman', serif; color: black; margin-top: 0in; margin-bottom: 0.0001pt; "><span style="font-size: 14pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125); "> </span><o:p></o:p></div><div style="margin-right: 0in; margin-left: 0in; font-size: 12pt; font-family: 'Times New Roman', serif; color: black; margin-top: 0in; margin-bottom: 0.0001pt; "><span style="font-size: 14pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125); ">Kirk Herander</span><o:p></o:p></div><div style="margin-right: 0in; margin-left: 0in; font-size: 12pt; font-family: 'Times New Roman', serif; color: black; margin-top: 0in; margin-bottom: 0.0001pt; "><span style="font-size: 14pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125); ">VT Solar, LLC</span><o:p></o:p></div><div style="margin-right: 0in; margin-left: 0in; font-size: 12pt; font-family: 'Times New Roman', serif; color: black; margin-top: 0in; margin-bottom: 0.0001pt; "><span style="font-size: 14pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125); ">dba Vermont Solar Engineering</span><o:p></o:p></div><div style="margin-right: 0in; margin-left: 0in; font-size: 12pt; font-family: 'Times New Roman', serif; color: black; margin-top: 0in; margin-bottom: 0.0001pt; "><span style="font-size: 14pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125); ">NABCEP<sup>TM<span class="Apple-converted-space"> </span></sup>Certified Inaugural Certificant</span><o:p></o:p></div><div style="margin-right: 0in; margin-left: 0in; font-size: 12pt; font-family: 'Times New Roman', serif; color: black; margin-top: 0in; margin-bottom: 0.0001pt; "><span style="font-size: 14pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125); ">NYSERDA-eligible Installer</span><o:p></o:p></div><div style="margin-right: 0in; margin-left: 0in; font-size: 12pt; font-family: 'Times New Roman', serif; color: black; margin-top: 0in; margin-bottom: 0.0001pt; "><span style="font-size: 14pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125); ">VT RE Incentive Program Partner</span><o:p></o:p></div><div style="margin-right: 0in; margin-left: 0in; font-size: 12pt; font-family: 'Times New Roman', serif; color: black; margin-top: 0in; margin-bottom: 0.0001pt; "><span style="font-size: 14pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125); ">802.863.1202</span><o:p></o:p></div><div style="margin-right: 0in; margin-left: 0in; font-size: 12pt; font-family: 'Times New Roman', serif; color: black; margin-top: 0in; margin-bottom: 0.0001pt; "><span style="font-size: 14pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125); "> </span><o:p></o:p></div><div style="margin-right: 0in; margin-left: 0in; font-size: 12pt; font-family: 'Times New Roman', serif; color: black; margin-top: 0in; margin-bottom: 0.0001pt; "><b><span style="font-size: 10pt; font-family: Tahoma, sans-serif; ">From:</span></b><span style="font-size: 10pt; font-family: Tahoma, sans-serif; "><span class="Apple-converted-space"> </span><a href="mailto:re-wrenches-bounces@lists.re-wrenches.org" style="color: blue; text-decoration: underline; ">re-wrenches-bounces@lists.re-wrenches.org</a><span class="Apple-converted-space"> </span>[<a href="mailto:re-wrenches-bounces@lists.re-wrenches.org" style="color: blue; text-decoration: underline; ">mailto:re-wrenches-bounces@lists.re-wrenches.org</a>]<span class="Apple-converted-space"> </span><b>On Behalf Of<span class="Apple-converted-space"> </span></b>Jason Szumlanski<br><b>Sent:</b><span class="Apple-converted-space"> </span>Tuesday, March 04, 2014 2:57 PM<br><b>To:</b><span class="Apple-converted-space"> </span>RE-wrenches<br><b>Subject:</b><span class="Apple-converted-space"> </span>Re: [RE-wrenches] conductors and the 120% rule</span><o:p></o:p></div><div style="margin-right: 0in; margin-left: 0in; font-size: 12pt; font-family: 'Times New Roman', serif; color: black; margin-top: 0in; margin-bottom: 0.0001pt; "> <o:p></o:p></div><div><div><div style="margin-right: 0in; margin-left: 0in; font-size: 12pt; font-family: 'Times New Roman', serif; color: black; margin-top: 0in; margin-bottom: 0.0001pt; "><span style="font-family: Verdana, sans-serif; ">Both the bus and conductors need to be rated for 217 amps minimum. As you mentioned, the bus is not a problem. The way I interpret it, the conductor size required would be after derate factors are applied. The rating of the conductor is ultimately dependent on the derate factors.</span><o:p></o:p></div></div><div><div style="margin-right: 0in; margin-left: 0in; font-size: 12pt; font-family: 'Times New Roman', serif; color: black; margin-top: 0in; margin-bottom: 0.0001pt; "><span style="font-family: Verdana, sans-serif; "> </span><o:p></o:p></div></div><div><div style="margin-right: 0in; margin-left: 0in; font-size: 12pt; font-family: 'Times New Roman', serif; color: black; margin-top: 0in; margin-bottom: 0.0001pt; "><span style="font-family: Verdana, sans-serif; ">If you can locate your subpanel adjacent to the main distribution panel, you may be able to use Exception #3 to 310.15(B)(2) by connecting the panels with a short nipple. I assume you are just looking at a number of conductor derate and not an ambient temperature derate.</span><o:p></o:p></div></div><div style="margin-right: 0in; margin-left: 0in; font-size: 12pt; font-family: 'Times New Roman', serif; color: black; margin-top: 0in; margin-bottom: 0.0001pt; "> <o:p></o:p></div><div id="WISESTAMP_SIG_gmail_session"><div></div></div></div></blockquote></div></div></span></blockquote></div></div><div><span>_______________________________________________</span><br><span>List sponsored by Home Power magazine</span><br><span></span><br><span>List Address: <a href="mailto:RE-wrenches@lists.re-wrenches.org">RE-wrenches@lists.re-wrenches.org</a></span><br><span></span><br><span>Change email address & settings:</span><br><span><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></span><br><span></span><br><span>List-Archive: <a href="http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org">http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org</a></span><br><span></span><br><span>List rules & etiquette:</span><br><span><a href="http://www.re-wrenches.org/etiquette.htm">www.re-wrenches.org/etiquette.htm</a></span><br><span></span><br><span>Check out participant bios:</span><br><span><a href="http://www.members.re-wrenches.org">www.members.re-wrenches.org</a></span><br><span></span><br></div></body></html>