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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:12.0pt;font-family:"Arial","sans-serif"'>Colleagues:<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif"'>I was invited to troubleshoot a Sunny Island system. What I found is a Sunny Island mini-grid system behaving oddly. The generator, when started with the SI, would run for a few minutes and then shut down. Further investigation revealed that the SIs were indicating that the inverters were sending lots of power back to the generator, even with the Sunny Boy turned off. <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif"'>I don’t know if this was actually the case, nor can I grasp how this could happen. The system was programmed as a PV/Gen only system. Fortunately I reached an off-grid tech at SMA and we were able to resolve the issue. I am not sure what we did but I suspect that simply rebooting the Sunny Islands was the cure.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif"'>I post this in case any of you experience this problem and could benefit from my experience. Also, I want to understand this better. Could it be true that the inverters could send power to the generator? I know the circuitry is there to sell to AC2, which is how this system would work as a true grid-interactive system, but how did it get triggered? Was it battery-selling to the generator? I welcome any comments.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif"'>What I am starting to think is that the Sunny Island system, like any feature rich system, is complicated and has the potential to be less reliable than simpler systems. On the plus side I could also think of these systems as job security for the knowledgeable technician.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif"'>Sincerely,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif"'>William<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'><img width=64 height=28 id="Picture_x0020_1" src="cid:image002.jpg@01CFD2C5.A1F6CC90" alt="Gradient Cap_mini"><br>Lic 773985<br><a href="http://www.millersolar.com/">millersolar.com</a><br>805-438-5600<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>