<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">My understanding was that the din mountable QOU breakers were rated to 125 vDC, and are internally the same as the QO. The difference was the connectors, and the mounting method.<div>I've used the QOUs reliably at 120 v nom on an EV, (but don't try this at home, kids)<br><div>We still use the QOs sometimes based on cost and availability, but I don't use them on anything over 24 v nominal anymore. </div><div>They were handiest in that one breaker line could cover AC and low volt DC.</div><div>With MPPT high voltage arrays, and some of Midnite Solar's new products (Mini DC & Baby DC boxes), though, we've found less and less of a place for the venerable QO line.</div><div><br><div>
<span class="Apple-style-span" style="border-collapse: separate; border-spacing: 0px 0px; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; text-align: auto; -khtml-text-decorations-in-effect: none; text-indent: 0px; -apple-text-size-adjust: auto; text-transform: none; orphans: 2; white-space: normal; widows: 2; word-spacing: 0px; "><div>R. Walters</div><div><a href="mailto:ray@solarray.com">ray@solarray.com</a></div><div>Solar Engineer</div><div><br class="khtml-block-placeholder"></div><div><br class="khtml-block-placeholder"></div><br class="Apple-interchange-newline"></span>
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<br><div><div>On May 16, 2010, at 2:25 PM, Kurt Albershardt wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">Square-D tells me they have tested the breakers to a higher voltage (can't recall now whether it was 80V or 125 VDC) but the listing is indeed for 48 Volts. 24V battery systems are useful for a lot of applications, but the unfortunate lack of a 5A breaker means we can not use them to derive a Class 2 supply, which would make them about 10x as useful to me.<div><br></div><div><br></div><div><br><div><div>On May 15, 2010, at 9:22 , jay peltz wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">Hi Rebekah,<div><br></div><div>The 48v is a max rating not a nominal rating.</div><div>So yes only good for 12 and 24v systems.</div><div><br></div><div>However with CBI breakers I don't understand why the need for QO for DC anymore?</div><div><br></div><div>jay</div><div><br></div><div>peltz power<br><div><div>On May 15, 2010, at 6:28 AM, Rebekah Hren wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><table cellspacing="0" cellpadding="0" border="0" style="position: static; z-index: auto; "><tbody><tr><td valign="top" style="font: inherit;">Hi,<div>One thing to be clear about is whether these are listed for "48 volt systems," or for max 48 volts?</div><div>I was under the impression that they were max 48 volts, meaning you really shouldn't use them on a system >24volts nominal.</div><div><br></div><div>Rebekah Hren</div><div>North Carolina</div><div> <div><br><br><a href="http://thecarbonfreehome.com/">http://thecarbonfreehome.com/</a><br><br>--- On <b>Sat, 5/15/10, Kurt Albershardt <i><<a href="mailto:info@es-ee.com">info@es-ee.com</a>></i></b> wrote:<br><blockquote style="border-left-width: 2px; border-left-style: solid; border-left-color: rgb(16, 16, 255); margin-left: 5px; padding-left: 5px; position: static; z-index: auto; "><br>From: Kurt Albershardt <<a href="mailto:info@es-ee.com">info@es-ee.com</a>><br>Subject: Re: [RE-wrenches] AC breakers used in DC applications<br>To: "RE-wrenches" <<a href="mailto:re-wrenches@lists.re-wrenches.org">re-wrenches@lists.re-wrenches.org</a>><br>Date: Saturday, May 15, 2010, 12:59 AM<br><br><div id="yiv787743009"><div>The Square-D catalogs are marginally clear on which breakers
are listed for DC and for what voltages, but when I tried to select an appropriate load center for a DC application earlier this year I quickly ran into a number of conflicts in their catalogs. Here is the response from Schneider tech support (Case# 4845778 on 1/19/10 in case anyone runs into problems with an inspector):</div><div><br></div><div><br></div><div><br></div>The load center catalog numbers listed below are UL LISTED, File E6294, for use on 48 V dc systems. The load centers listed ARE NOT MARKED for use on this voltage system, however are suitable for the application. QO branch breakers, 10-70 ampere (1 and 2 pole) are also UL LISTED for use on 48V dc systems. Short circuit current rating is limited to 5,000 amperes when used on 48V dc.<br>QO24L70F, S or RB QO612L100F, S, DF, DS, DFCU, DSCU, RB, TRB or RBCU QO816L100F, S, DF, DS, DFCU, DSCU, RB or RBCU<br>QO112L125G or QO11224L125G QO116L125G QO11624L125G QO120L125G
QO12024L125G QO124L125G or QO12030L150G QO124L150G QO130L150G or QO112L200G or QO130L200G or QO13040L200G QO142L225G or<br>GRB or GRB<br>or GRB<br>GRB<br><div>GRB GRB GRB or GRB QO142L225GRB</div><div><br></div><div><br></div><div>I can email the PDF to anyone who needs a copy.</div><div><br></div><div> </div></div></blockquote></div></div></td></tr></tbody></table></blockquote></div><br></div></div>_______________________________________________<br>List sponsored by Home Power magazine<br><br>List Address: <a href="mailto:RE-wrenches@lists.re-wrenches.org">RE-wrenches@lists.re-wrenches.org</a><br><br>Options & settings:<br><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><br><br>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><br><br>List rules & etiquette:<br><a href="http://www.re-wrenches.org/etiquette.htm">www.re-wrenches.org/etiquette.htm</a><br><br>Check out participant bios:<br>www.members.re-wrenches.org<br><br></blockquote></div><br></div></div>_______________________________________________<br>List sponsored by Home Power magazine<br><br>List Address: <a href="mailto:RE-wrenches@lists.re-wrenches.org">RE-wrenches@lists.re-wrenches.org</a><br><br>Options & settings:<br><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><br><br>List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org<br><br>List rules & etiquette:<br>www.re-wrenches.org/etiquette.htm<br><br>Check out participant bios:<br>www.members.re-wrenches.org<br><br></blockquote></div><br></div></div></body></html>