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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:14.0pt;color:#1F497D'>One Question: Output of the SunnyBoy is 240vac. So this is fed to the critical load panel, of which the SunnyIsland 120 vac output is fed to. So we need a 120/240 step up transformer between the SunnyIsland and the critical load panel to fully take advantage of the Sunnyboy array for battery charging, correct?.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:14.0pt;color:#1F497D'><o:p> </o:p></span></p><div><p class=MsoNormal><span style='font-size:14.0pt;color:#1F497D'>Kirk Herander<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:14.0pt;color:#1F497D'>VT Solar, LLC<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:14.0pt;color:#1F497D'>dba Vermont Solar Engineering<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:14.0pt;color:#1F497D'>NABCEP<sup>TM </sup>Certified installer Charter Member<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:14.0pt;color:#1F497D'>NYSERDA-eligible Installer<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:14.0pt;color:#1F497D'>VT RE Incentive Program Partner<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:14.0pt;color:#1F497D'>802.863.1202<o:p></o:p></span></p></div><p class=MsoNormal><span style='font-size:14.0pt;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>David Katz<br><b>Sent:</b> Friday, October 05, 2012 2:11 AM<br><b>To:</b> RE-wrenches<br><b>Subject:</b> Re: [RE-wrenches] AC coupling and Outback inverters<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Verdana","sans-serif"'>Hi Kirk,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Verdana","sans-serif"'>All of the Outback inverters will work AC coupled (GT and FX) as will any bi-directional H-bridge type inverter. I have used old Trace SW’s, SunnyIsland, Apollo TSW, Magnum AE and now I am using an Outback Radian to do exactly what you are talking about. I have 6 kW of grid tie inverter and an additional 4kw of modules running through a Xantrex 600 volt charge controller to the batteries that the Radian runs on. It all works flawless as long as you have a provision for protecting the batteries when the gid is down and the grid-tie PV system is making more power than the loads are using. <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Verdana","sans-serif"'>If the customer has SMA inverters, I would recommend using a SunnyIsland because the battery control when the grid goes down is so elegant. Everything else is a bit of a kludge.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Verdana","sans-serif"'><o:p> </o:p></span></p><div><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Verdana","sans-serif"'>David Katz<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Verdana","sans-serif"'>CTO & Founder<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Verdana","sans-serif"'>AEE Solar Inc<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Verdana","sans-serif"'>P: 707 825-1200<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Verdana","sans-serif"'>F: 707 825-1202<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Verdana","sans-serif"'><a href="mailto:dkatz@aeesolar.com">dkatz@aeesolar.com</a><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Verdana","sans-serif"'><a href="http://www.aeesolar.com">www.aeesolar.com</a><o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;text-autospace:none'><span style='font-size:12.0pt;font-family:"Arial","sans-serif"'> </span><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'><o:p></o:p></span></p></div><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Verdana","sans-serif"'><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"'> <a href="mailto:re-wrenches-bounces@lists.re-wrenches.org">re-wrenches-bounces@lists.re-wrenches.org</a> <a href="mailto:[mailto:re-wrenches-bounces@lists.re-wrenches.org]">[mailto:re-wrenches-bounces@lists.re-wrenches.org]</a> <b>On Behalf Of </b>Kirk Herander<br><b>Sent:</b> Thursday, October 04, 2012 2:11 PM<br><b>To:</b> RE-wrenches<br><b>Subject:</b> [RE-wrenches] AC coupling and Outback inverters<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'>I have AC-coupled an Outback quad-stack with multiple SunnyBoy 6000US inverters and it’s been running fine for 4 years. I used the off-grid version of Outbacks.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:14.0pt'>Now I have an application where a customer wants to add battery backup to an existing SunnyBoy 5000US system. And expand his array by a couple KW. So I’m thinking of using a GT Outback w/ batteries to handle the critical loads and feed the extra 2kw of PV (charging the batteries through an MX60) to the grid. And I’d like to AC-couple the SunnyBoy so the original 5 kw array can also charge the batteries, BUT I remember, at least I think so, that the GT inverter cannot be AC-coupled, only the off-grid version. Is this correct? Thanks.<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'>Kirk Herander<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:14.0pt'>VT Solar, LLC<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:14.0pt'>dba Vermont Solar Engineering<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:14.0pt'>NABCEP<sup>TM </sup>Certified installer Charter Member<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:14.0pt'>NYSERDA-eligible Installer<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:14.0pt'>VT RE Incentive Program Partner<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:14.0pt'>802.863.1202<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>