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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='color:#1F497D'>We have been using the Siemens line of disconnects. They are designed for use on DC circuits, and are UL listed for this application…<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><a href="http://www.sea.siemens.com/us/internet-dms/btlv/CircuitProtection/HeavyDutySafetySwitches/docs_HeavyDutySafetySwitches/PV%20datasheet%20Sept2010.pdf">http://www.sea.siemens.com/us/internet-dms/btlv/CircuitProtection/HeavyDutySafetySwitches/docs_HeavyDutySafetySwitches/PV%20datasheet%20Sept2010.pdf</a><o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>-Glenn<o:p></o:p></span></p><p class=MsoNormal><span style='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>Kirk Herander<br><b>Sent:</b> Monday, March 19, 2012 4:41 PM<br><b>To:</b> RE-wrenches<br><b>Subject:</b> [RE-wrenches] Sqd H series disconnects<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><span style='font-size:14.0pt'>Hello,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:14.0pt'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:14.0pt'>I am combining -4- series strings at the array in a series-fused combiner. The sum Isc of the four strings is 22.64 adc. I want to use either a HU361(30 amp) or HU362(60 amp) as a disco at the inverter instead of running individual strings a long distance from the arrays to the factory-supplied SMA fused disco. So the Isc rating for the HU361 Is 11.5 amps per pole, the HU362 is 38 amps per pole. Although not clear in the SQD datasheet, I think that if two poles are series together the DC(non-pv dc) rating is a full 30 amps for the HU361, and 60 amps for the 362. But the limiting factor in a PV application is the per-pole Isc rating, regardless of putting 2 poles in series (this does not increase the Isc rating of the respective disconnect), correct? I’m assuming my only choice in this instance is to use the 60 amp disco?<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:14.0pt'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt'>Kirk Herander<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt'>VT Solar, LLC<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt'>dba Vermont Solar Engineering<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt'>NABCEP<sup>TM </sup>Certified installer Charter Member<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt'>NYSERDA-eligible Installer<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt'>VT RE Incentive Program Partner<o:p></o:p></span></p><p class=MsoNormal>802.863.1202<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>