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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>Folks,<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I was told that because the HI grid has poor frequency control, grid-tied inverters have to have their low frequency limit set to 57 Hz so they can ride out the worst low frequency events.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I find it hard to believe that this has been done for every single inverter installed in HI.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>But, what do I know.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Can anyone shed some light on this?<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Thanks,<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Mark Frye<o:p></o:p></p><p class=MsoNormal>Berkeley Solar Electric Systems<o:p></o:p></p></div></body></html>