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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal>I need some help please! I’m quickly losing credibility with two of my customers.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>We have two installations with Sunpreme GxB 350 bi-facial modules and Fronius IG inverters. They keep throwing Error code 240 – arc fault on the Fronius IG. <o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>We’ve been up and down these installation three times checking connections, replacing connectors, tightening connections, checking for chafed wires. Nothing to cause any visible angst.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>The team here is wondering is perhaps the module itself might be the source of the problem, with some DC arcing inside the J-Box. Any thoughts? We can’t open the j-box on an broken module (be careful handling frameless glass on glass modules <span style='font-family:Wingdings'>J</span>) because there doesn’t appear to anything accessible with modern potted j-boxes.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>As for the conditions when we get these arc fault codes – typically the peak of a sunny day when they’re making max power.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Each of the installations is a bit different. On the 7KW install with Fronius 7.5, we’ve run the two strings (10 modules each) back to the inverter separately. On the 10.5KW install with the Fronius 10.0, we ran 3 strings of 10 to a combiner box, then one set of conductor back to the Fronius 10.0 where we used the distribution plate to spead the amperage across the six string input channels.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I’m stuck – any thoughts on other potential arc-fault causes?<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><b>Howard “Scot” Arey<o:p></o:p></b></p><p class=MsoNormal>254-300-1228<o:p></o:p></p><p class=MsoNormal><a href="mailto:scot.arey@solarcentex.com">scot.arey@solarcentex.com</a><o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><img border=0 width=209 height=205 id="Picture_x0020_1" src="cid:image001.jpg@01D0A998.AFB80420" alt="logo from letterhead"><o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>