<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"></head><body dir="auto"><div>We had the same request in NC by Duke Energy. The inverter mfg. says they can do it but it'd be outside of the values on the label that the inverter is listed to. I don't think Duke cares, but the AHJ may. </div><div><br></div><div>Brian<br><br>Typos courtesy of my iPhone. </div><div><br>On Feb 4, 2013, at 6:44 PM, "Mark Frye" <<a href="mailto:markf@berkeleysolar.com">markf@berkeleysolar.com</a>> wrote:<br><br></div><blockquote type="cite"><div><meta http-equiv="Content-Type" content="text/html; charset=us-ascii"><meta name="Generator" content="Microsoft Word 12 (filtered medium)"><style><!--
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</o:shapelayout></xml><![endif]--><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></div></blockquote><blockquote type="cite"><div><span>_______________________________________________</span><br><span>List sponsored by Home Power magazine</span><br><span></span><br><span>List Address: <a href="mailto:RE-wrenches@lists.re-wrenches.org">RE-wrenches@lists.re-wrenches.org</a></span><br><span></span><br><span>Options & settings:</span><br><span><a href="http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org">http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org</a></span><br><span></span><br><span>List-Archive: <a href="http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org">http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org</a></span><br><span></span><br><span>List rules & etiquette:</span><br><span><a href="http://www.re-wrenches.org/etiquette.htm">www.re-wrenches.org/etiquette.htm</a></span><br><span></span><br><span>Check out participant bios:</span><br><span><a href="http://www.members.re-wrenches.org">www.members.re-wrenches.org</a></span><br><span></span><br></div></blockquote></body></html>