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--></style></head><body lang="EN-US" link="blue" vlink="purple"><div class="WordSection1"><p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Verdana","sans-serif"">Friends:</span></p><p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Verdana","sans-serif""> </span></p><p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Verdana","sans-serif"">I was whining on this forum recently about an <a href="https://millersolar.com/MillerSolar/Portfolio/Inverters/battery_iinverters/JP_Radian/JP_Radian.html">off-grid system</a> that was tripping GFI and AFCI breakers and devices. </span></p><p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Verdana","sans-serif""> </span></p><p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Verdana","sans-serif"">The problem seemed to be related to high THD on the voltage waveform experienced when the generator was charging the batteries. We first discovered this THD problem when inexpensive AC voltmeters disagreed with True-RMS AC voltmeters. Subsequent testing with Power Quality Monitors indicated 28% THD of the voltage waveform.</span></p><p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Verdana","sans-serif""> </span></p><p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Verdana","sans-serif"">Well it turns out that when these three-stack Radian inverters were set for Generator AC input mode, the charger circuits generated a lot of THD (28%f in our case). However, when we selected Backup, Support or UPS mode the THD went down to 3.5%f.</span></p><p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Verdana","sans-serif""> </span></p><p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Verdana","sans-serif"">For those of you that have had various appliances that perform poorly with a given inverter, you might check to see if the failures coincide with generator run. It could be that it is the charging circuit that is the culprit and not the inverting circuit. Knowing this could be helpful.</span></p><p class="MsoNormal" style="margin-top:12.0pt"><span style="font-size:12.0pt;font-family:"Verdana","sans-serif"">I hope this information may prevent one or more of you from tearing out hair. For a full report of our travails, see this <a href="https://millersolar.com/MillerSolar/case_studies/25_GFI%20Tripping/GFI_Tripping.html">link</a>.</span></p><p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Verdana","sans-serif""> </span></p><p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Verdana","sans-serif"">William</span></p><p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Verdana","sans-serif""> </span></p><p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Verdana","sans-serif"">PS: It has only been a few days since we adjusted the settings, but so far no more tripping.</span></p><p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Verdana","sans-serif""> </span></p><p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Verdana","sans-serif"">WM</span></p><p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Verdana","sans-serif""> </span></p><p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial","sans-serif"">Miller Solar</span></p><p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial","sans-serif"">17395 Oak Road, Atascadero, CA 93422</span></p><p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial","sans-serif"">805-438-5600</span></p><p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial","sans-serif""><a href="http://www.millersolar.com/">www.millersolar.com</a></span></p><p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial","sans-serif"">CA Lic. 773985</span></p><p class="MsoNormal"> </p></div></body></html>