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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='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>I think I just read that SMA has changed their long-standing 15A per string fuses to 20A.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>You might look to see if it applies to existing systems.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Hope it helps.<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'>Glenn<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 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>Jason Szumlanski<br><b>Sent:</b> Thursday, February 06, 2014 12:50 PM<br><b>To:</b> RE-wrenches<br><b>Subject:</b> [RE-wrenches] DC Series Fusing in inverters<o:p></o:p></span></p></div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal><span style='font-family:"Verdana","sans-serif"'>SMA inverters typically come with 15A KLKD fuses pre-installed. I have seen a bunch of blown fuses recently (after cold weather)... It seems that some dealers are just assuming the 15A fuse is okay for series strings and not doing the calculations. I've been finding quite a few Evergreen systems or parallel connected two-string SunPower systems that should have 20A fuses per NEC 690.8. The problem does seem to be worse where inverters are exposed to direct sunlight, presumably from fuses that no longer meet their ampacity rating due to heat.<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Verdana","sans-serif"'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Verdana","sans-serif"'>Anyone else run into this frequently?<o:p></o:p></span></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><span style='font-family:"Verdana","sans-serif"'>Jason Szumlanski<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Verdana","sans-serif"'>Fafco Solar<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Verdana","sans-serif"'><o:p> </o:p></span></p></div></div></div></body></html>