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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'>Eric,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>For a 6kW system on a reasonable size commercial service, it shouldn’t be a problem to stack your 2 inverters on one or two legs of the 3-phase service. Loads are never perfectly balanced, so synchronous generators don’t need to be either, up to a point. Ask the utility if you can feed the 6kW in on one leg. They’ll look at their transformer for the service in question and make a decision. If they let you do it, just try to feed in on the most heavily loaded leg of the 3-phase service.<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'>Regards,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>-Hans<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>Eric Thomas<br><b>Sent:</b> Monday, April 25, 2011 11:01 AM<br><b>To:</b> re-wrenches@lists.re-wrenches.org<br><b>Subject:</b> [RE-wrenches] Single phase to three phase interconnect<o:p></o:p></span></p></div><p class=MsoNormal><o:p> </o:p></p><p>While commercial solar work is newer to me, im surprised this hasn't been addressed very much in our forum: Interconnecting single phase inverters to three phase services. We are laying out a 6kW system using Silicon Energy Cascade modules and Aurora PVI inverters (either 2 or 3 PVI 3.0's). The challenge is finding a way to easily tie two of these inverters into the existing 3phase service. I've been reading up on Sunny Boys tech notes and on this forum about imbalance and such, but im still not comfortable enough with tie in. Due to the string configuration options, I can add a third inverter and use a three phase subpanel to aggregate the inverters then tie them in. But adding a third inverter seems like a goofy solution. In looking at available equipment, transformers, phase converters etc, I can't seem to find the right fit. Any ideas?<o:p></o:p></p><p>This system does not have a three phase inverter option due to Made in WA req's. <o:p></o:p></p><p>Thanks!<o:p></o:p></p><p>Eric Thomas<br>Solar Epiphany LLC<o:p></o:p></p></div></body></html>