<HTML xmlns="http://www.w3.org/TR/REC-html40" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:v="urn:schemas-microsoft-com:vml" xmlns:w="urn:schemas-microsoft-com:office:word"><head><META content="text/html; charset=iso-8859-1" http-equiv="Content-Type">
<meta content="Microsoft Word 14 (filtered medium)" name=Generator><!--[if !mso]><style>v\:* {behavior:url(#default#VML);}
o\:* {behavior:url(#default#VML);}
w\:* {behavior:url(#default#VML);}
.shape {behavior:url(#default#VML);}
</style><![endif]--><style><!--
/* Font Definitions */
@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;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0in;
margin-bottom:.0001pt;
font-size:12.0pt;
font-family:"Times New Roman","serif";}
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.MsoAcetate, li.MsoAcetate, div.MsoAcetate
{mso-style-priority:99;
mso-style-link:"Balloon Text Char";
margin:0in;
margin-bottom:.0001pt;
font-size:8.0pt;
font-family:"Tahoma","sans-serif";}
p.MsoListParagraph, li.MsoListParagraph, div.MsoListParagraph
{mso-style-priority:34;
margin-top:0in;
margin-right:0in;
margin-bottom:0in;
margin-left:.5in;
margin-bottom:.0001pt;
font-size:12.0pt;
font-family:"Times New Roman","serif";}
span.EmailStyle18
{mso-style-type:personal;
font-family:"Calibri","sans-serif";
color:#1F497D;}
span.EmailStyle19
{mso-style-type:personal-reply;
font-family:"Calibri","sans-serif";
color:#1F497D;}
span.BalloonTextChar
{mso-style-name:"Balloon Text Char";
mso-style-priority:99;
mso-style-link:"Balloon Text";
font-family:"Tahoma","sans-serif";}
.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;}
/* List Definitions */
@list l0
{mso-list-id:743258974;
mso-list-type:hybrid;
mso-list-template-ids:1352305210 67698705 67698713 67698715 67698703 67698713 67698715 67698703 67698713 67698715;}
@list l0:level1
{mso-level-text:"%1\)";
mso-level-tab-stop:none;
mso-level-number-position:left;
text-indent:-.25in;}
@list l0:level2
{mso-level-number-format:alpha-lower;
mso-level-tab-stop:none;
mso-level-number-position:left;
text-indent:-.25in;}
@list l0:level3
{mso-level-number-format:roman-lower;
mso-level-tab-stop:none;
mso-level-number-position:right;
text-indent:-9.0pt;}
@list l0:level4
{mso-level-tab-stop:none;
mso-level-number-position:left;
text-indent:-.25in;}
@list l0:level5
{mso-level-number-format:alpha-lower;
mso-level-tab-stop:none;
mso-level-number-position:left;
text-indent:-.25in;}
@list l0:level6
{mso-level-number-format:roman-lower;
mso-level-tab-stop:none;
mso-level-number-position:right;
text-indent:-9.0pt;}
@list l0:level7
{mso-level-tab-stop:none;
mso-level-number-position:left;
text-indent:-.25in;}
@list l0:level8
{mso-level-number-format:alpha-lower;
mso-level-tab-stop:none;
mso-level-number-position:left;
text-indent:-.25in;}
@list l0:level9
{mso-level-number-format:roman-lower;
mso-level-tab-stop:none;
mso-level-number-position:right;
text-indent:-9.0pt;}
ol
{margin-bottom:0in;}
ul
{margin-bottom:0in;}
--></style><!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]--></head><BODY>
<DIV><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Chris/August:<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoListParagraph style='text-indent:-.25in;mso-list:l0 level1 lfo1'><![if !supportLists]><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><span style='mso-list:Ignore'>1)<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>The terminal temperatures in a piece of equipment should have been evaluated as part of the Listing process. The manufacturer should specify the temperature rating of the terminals and the wire temperature and type, e.g. (Al/Cu). The NRTL will do temperature measurements on the minimum specified wire and terminals at max power and max specified ambient. If all the temperatures are ok then the product would be approved for 90C wire even if the temperature rating of that terminal was lower. This is because a Listed terminal is approved for general use and no temperature tests will be run in the field.<o:p></o:p></span></p><p class=MsoListParagraph><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoListParagraph><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>This issue also ties into the minimum and maximum wire sizes allowed and the wire bending space inside the product. For Example: A product might be designed for copper wire only due to wire bending. The wire bending space required for the larger Al wire might be greater than available space in the product (this is typically a significant cost driver). The use of Al wire would be precluded even if the Al wire would fit in the terminal and the terminal were rated from Al/Cu. In our case we specify 90C copper wire only and test for that at the minimum wire size allowed by NEC to carry the design current and at max power / max ambient we specify. Min and max torques must also be specified. All of this should be on the unit rating label or in the manual.<o:p></o:p></span></p><p class=MsoListParagraph><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoListParagraph><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>What happens on the other end of the wire is a separate issue and you need to make sure the terminal at the other end also meets NEC requirement at the conditions specified by the manufacturer of that equipment.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Best Regards,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>John Berdner<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>General Manager, North America<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><img alt=SmallBannerPictEngnew height=113 id="Picture_x0020_1" src="cid:image001.jpg@01CDFA3C.9E6DCC30" width=468><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>SolarEdge Technologies, Inc.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>3347 Gateway Boulevard, Fremont CA 94538 USA </span><b><i><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#C00000'>(*Please note of our new address.)</span></i></b><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><br>T: 510.498.3200, X 747<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>M: 530.277.4894 <o:p></o:p></span></p></div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><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> Thursday, January 24, 2013 11:59 AM<br><b>To:</b> RE-wrenches<br><b>Subject:</b> Re: [RE-wrenches] Equipment Rating vs. Terminal/Lug Rating<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Hi Chris,</span><o:p></o:p></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Here are my thoughts on your questions/notes below. Please note that I'm in no way an expert in this field, I've only had to deal with it from time to time through our workings with various situations and AHJs. </span><o:p></o:p></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p><p class=MsoListParagraph><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>1.</span><span style='font-size:7.0pt;color:#1F497D'> </span><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>I believe terminal and equipment ratings can vary within one piece of equipment. Even a typical breaker might have a 70°C rated terminal but is only rated at 40°C max operating temperature. I would think that this is the manufacturer's decision on what rating to apply to their overall equipment - and it might very well be driven by a UL type test but I don't know. I've called inverter manufacturers a few times to try to figure out what their terminal and or equipment temperature ratings are. Most of the time they don't know. More recently I've been told 75°C but wasn't given any documentation to prove it. I just saw a recent SunPower branded PowerOne inverter manual which stated it has 90°C terminal ratings.</span><o:p></o:p></p><p class=MsoListParagraph><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>2.</span><span style='font-size:7.0pt;color:#1F497D'> </span><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>NEC 110.14(C) addresses this a bit. My understanding is that the current standard for equipment rated over 100 A is 75°C (and 60 °C for less than 100 A) but that older equipment, say 40 years + old, was 60°C. This is what our inspectors in San Francisco have told me and seems to be consistent to what I see on the equipment labels (we take digital photos of equipment labels for each project) for existing equipment. Once again, this is only a rough rule of thumb and I'm sure that there are other temp ratings for certain types of equipment. For example, I'm looking at a Murray LC008DF residential load center which states "Size wire only to 60°C or 75°C ampacity limits. Size wire in accordance with breaker markings and wire bending space requirements." The breaker then in turn says "CU-AL 60/75°C WIRE."</span><o:p></o:p></p><p class=MsoListParagraph><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>3.</span><span style='font-size:7.0pt;color:#1F497D'> </span><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Good question. </span><o:p></o:p></p><p class=MsoListParagraph><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>4.</span><span style='font-size:7.0pt;color:#1F497D'> </span><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>I guess that would be specified in the equipment manual or maybe be some internal manufacturer documentation. Or maybe once again a UL-driven type requirement?</span><o:p></o:p></p><p class=MsoListParagraph><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>5.</span><span style='font-size:7.0pt;color:#1F497D'> </span><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Most modern load centers, panel boards, disconnect switches that I've seen are all 60/75 °C rated. I'm looking at the device label on a Square D DU324 disconnect and it says "Lugs suitable for 75°C CU - AL conductors." </span><o:p></o:p></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Anyway, this might provide some info for you. Do you have a particular issue in mind that you're trying to solve for?</span><o:p></o:p></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Best, August</span><o:p></o:p></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p><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>Chris Anderson<br><b>Sent:</b> Thursday, January 24, 2013 6:52 AM<br><b>To:</b> RE-wrenches<br><b>Subject:</b> [RE-wrenches] Equipment Rating vs. Terminal/Lug Rating</span><o:p></o:p></p><p class=MsoNormal> <o:p></o:p></p><p class=MsoNormal style='margin-bottom:12.0pt'><span style='font-family:"Arial","sans-serif";color:#222222;background:white'>How to properly size conductors based on insulation and termination temperature ratings is an often discussed topic among PV designers. Those discussion have provided clarity and understanding of the issue but determining equipment rating, as opposed to termination rating, is still unclear. See below for questions and discussion.</span><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:#222222'><br><br><span style='background:white'>According to Square D documentation on terminations (Bulletin No. 0110DB9901R2/02, March 2002):</span></span><o:p></o:p></p><p class=MsoNormal style='background:white'><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:#222222'>The Underwriters Laboratories® General Information on Electrical Equipment Directory states the following about terminations: “A 75 °C or 90 °C temperature marking on a terminal (e.g., AL7, CU7AL, AL7CU or AL9, CU9AL, AL9CU) does not in itself indicate that a 75 °C or 90 °C insulated wire can be used unless the equipment in which the terminals are installed is marked for 75 °C or 90 °C.”</span><o:p></o:p></p><div><p class=MsoNormal style='background:white'><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:#222222'> </span><o:p></o:p></p></div><div><p class=MsoNormal style='background:white'><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:#222222'>Questions are as follows:</span><o:p></o:p></p><p class=MsoNormal style='margin-left:47.25pt;background:white'><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:#222222'>1.</span><span style='font-size:7.0pt;color:#222222'> </span><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:#222222'>If a piece of equipment contains any individual components that are rated for 75deg is it still possible to for the overall rating to be 90deg? Presumably, relative location/distance of 75deg-rated components may allow for sufficient heat dissipation between components.</span><o:p></o:p></p><p class=MsoNormal style='margin-left:47.25pt;background:white'><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:#222222'>2.</span><span style='font-size:7.0pt;color:#222222'> </span><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:#222222'>If a piece of equipment does not have a temperature explicitly marked on it's exterior is there an implied rating? 75deg? 60deg?</span><o:p></o:p></p><p class=MsoNormal style='margin-left:47.25pt;background:white'><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:#222222'>3.</span><span style='font-size:7.0pt;color:#222222'> </span><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:#222222'>Are ratings determined by a specific UL test or are they manufacturer specified?</span><o:p></o:p></p><p class=MsoNormal style='margin-left:47.25pt;background:white'><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:#222222'>4.</span><span style='font-size:7.0pt;color:#222222'> </span><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:#222222'>Is there a specific distance of separation required between two differently rated pieces of equipment and/or terminations? Certain equipment manufacturers have stated that an extended terminal protruding from a 75deg-rated component would allow for a 90deg-rated lug and 90deg conductor sizing.</span><o:p></o:p></p><p class=MsoNormal style='margin-left:47.25pt;background:white'><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:#222222'>5.</span><span style='font-size:7.0pt;color:#222222'> </span><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:#222222'>Square D documentation indicates that <u>all</u> 600 V equipment is either 60 or 75deg-rated. Is this true? Referenced documentation is 11 years old. Perhaps this has changed?</span><o:p></o:p></p><p class=MsoNormal style='margin-left:83.25pt;background:white'><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:#222222'>1.</span><span style='font-size:7.0pt;color:#222222'> </span><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:#222222'>Pertinent excerpt: For electrical equipment rated for 600 V and less, terminations are typically rated at 60 °C, 75 °C or 60/75 °C. No distribution or utilization equipment is listed and identified for the use of 90 °C wire at its 90 °C ampacity.</span><o:p></o:p></p></div><div><p class=MsoNormal style='background:white'><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:#222222'>Thanks for any input or advice,</span><o:p></o:p></p></div><div><p class=MsoNormal> <o:p></o:p></p></div><p class=MsoNormal>-- <o:p></o:p></p><div><p class=MsoNormal> <o:p></o:p></p></div><div><p class=MsoNormal>Regards,<o:p></o:p></p></div><div><p class=MsoNormal> <o:p></o:p></p></div><p class=MsoNormal>Chris Anderson + Ben Walter<o:p></o:p></p><div><p class=MsoNormal>Borrego Solar Systems<o:p></o:p></p></div><div><p class=MsoNormal>Lowell, MA 01851<o:p></o:p></p></div><div><p class=MsoNormal> <o:p></o:p></p></div></div></DIV>
<DIV STYLE="FONT-FAMILY: Courier New; FONT-SIZE: 9pt">
<P CLASS="MsoNormal" STYLE="MARGIN: 0cm 0cm 0pt"><FONT FACE="Calibri"><SPAN STYLE="COLOR: navy; FONT-SIZE: 10pt">CONFIDENTIALITY NOTICE: This e-mail and its attachments are intended only for the use of the individual or entity who is the intended recipient and may contain information that is privileged, confidential and exempt from disclosure or any type of use under applicable law. If the reader of this e-mail is not the intended recipient, or the employee, agent, or representative responsible for delivering the e-mail to the intended recipient, you are hereby notified that any dissemination, distribution, copying, or other use of this e-mail is strictly prohibited. If you have received this e-mail in error, please reply immediately to the sender.</SPAN></FONT> </P><FONT FACE="Calibri"><SPAN STYLE="COLOR: navy; FONT-SIZE: 10pt">
<P CLASS="MsoNormal" STYLE="MARGIN: 0cm 0cm 0pt"><B><SPAN LANG="DE" STYLE="FONT-FAMILY: Webdings; COLOR: green; FONT-SIZE: 13.5pt; mso-ansi-language: DE">P</SPAN></B><SPAN STYLE="COLOR: green; FONT-SIZE: 10pt"> Please think of the environment before printing this email</SPAN><SPAN STYLE="COLOR: #4f81bd"></SPAN></P></SPAN></FONT></DIV></BODY></HTML>