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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'>Wrenches,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>I’m have a mental block with battery backup systems such as the Outback Radian. Perhaps someone can help me get over it!<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Essentially these systems sell back power off the top of the battery bank and the array is maintaining the state of charge of the battery bank through traditional charge controllers. If you have a modest battery bank sized for limited use on critical circuits and a good size array for the benefit of net metering I would think it would be necessary to limit the current the charge controllers are capable of delivering to the battery bank to prevent damage to the batteries when the controllers are Bulking or Absorbing, but then it would seem that we limiting the utility of the larger array. If the current from the controllers was not limited they will self-limit as voltage rises, plus I suppose they will mostly be in float mode except when the batteries are cycled but again it seems that we are limiting the capability of the array compared to a straight grid tied system with a traditional grid tied only inverter.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>An example would be a 8000 watt array using a couple of flexmax80 controllers with a string of 8 - L16 AGMs feeding a Radian.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>What am I missing here?<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Thanks <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Rich<o:p></o:p></span></p><div><div><div><div><p class=MsoNormal><span style='font-size:10.5pt;font-family:"Arial","sans-serif"'><o:p> </o:p></span></p></div></div></div></div></div></body></html>