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--></style></head><body lang="EN-US" link="blue" vlink="purple"><div class="WordSection1"><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1f497d">Stuart:</span></p><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1f497d"> </span></p><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1f497d">I understand the concern and appreciate the consideration to provide more reliability. The approach you suggested sounds like a band-aid, not a cure. </span></p><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1f497d"> </span></p><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1f497d">I do not know if this complete shutdown is required by the listing (a feature) or is just a bug. Does anyone have information on this? If it is not required, the manufacturers should certainly correct these problems. </span></p><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1f497d"> </span></p><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1f497d">This may be a case against All-in-on inverters. If there is a PV arc fault on systems with separate charge controllers the inverter will not curtail operation and it’s pass-through capabilities.</span></p><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1f497d"> </span></p><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1f497d">William Miller</span></p><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1f497d"> </span></p><p class="MsoNormal"><span style="font-family:"Arial","sans-serif";color:#1f497d">Miller Solar</span></p><p class="MsoNormal"><span style="font-family:"Arial","sans-serif";color:#1f497d">17395 Oak Road, Atascadero, CA 93422</span></p><p class="MsoNormal"><span style="font-family:"Arial","sans-serif";color:#1f497d">805-438-5600</span></p><p class="MsoNormal"><span style="font-family:"Arial","sans-serif";color:#1f497d"><a href="http://www.millersolar.com/"><span style="color:blue">www.millersolar.com</span></a></span></p><p class="MsoNormal"><span style="font-family:"Arial","sans-serif";color:#1f497d">CA Lic. 773985</span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d"> </span></p><p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1f497d"> </span></p><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 [mailto:<a href="mailto:re-wrenches-bounces@lists.re-wrenches.org">re-wrenches-bounces@lists.re-wrenches.org</a>] <b>On Behalf Of </b>Stuart Kriendler via RE-wrenches<br><b>Sent:</b> Tuesday, January 14, 2025 11:09 AM<br><b>To:</b> <a href="mailto:re-wrenches@lists.re-wrenches.org">re-wrenches@lists.re-wrenches.org</a><br><b>Cc:</b> Stuart Kriendler<br><b>Subject:</b> [RE-wrenches] ATS models to bypass GT hybrid inverters for maintenance/faults</span></p><p class="MsoNormal"> </p><div><div><p class="MsoNormal">Good day Wrenches,</p></div><div><p class="MsoNormal"> </p></div><div><p class="MsoNormal">2025 looks to be the year for installing more grid tied (GT) battery back up hybrid inverters on new and existing GT PV systems in a whole house backup scenario</p></div><div><p class="MsoNormal">i.e. Utility - Hybrid Inverter - House Loads</p></div><div><p class="MsoNormal"> </p></div><div><p class="MsoNormal">With these newer GT hybrids so 'sensitive', any fault on the PV side can cause them to shut down, thus stopping power to the house. </p></div><div><p class="MsoNormal">To minimise this it seems sensible to add an ATS to the system such that if/when the hybrid faults, the ATS w switch to grid power, bypass the hybrid, and power the house.</p></div><div><p class="MsoNormal">This could save an emergency truck roll or late night phone call for installers.</p></div><div><p class="MsoNormal"> </p></div><div><p class="MsoNormal">Anyone have experience on good value-for-money Listed automatic transfer switches that would do the job, 200A, 120/240V?</p></div><div><p class="MsoNormal"> </p></div><div><p class="MsoNormal">Two name brand options that came up on the less expensive end of the spectrum are:</p></div><div><p class="MsoNormal"><span style="color:#222222">- </span>Generac RXSW200A3 (<a href="https://www.generac.com/residential-products/standby-generator-transfer-switches/automatic/rxsw200a3/">https://www.generac.com/residential-products/standby-generator-transfer-switches/automatic/rxsw200a3/</a>)</p></div><div><p class="MsoNormal"> </p></div><div><p class="MsoNormal">- <b><span style="font-size:11.0pt;font-family:Aptos;color:black">Kohler 200-amp, Service Entrance RXT ATS | RXT-JFNC-200ASEQS4 (</span></b><a href="https://www.kohler.com/content/dam/kohler-com-NA/Lifestyle/PDF/PDF-g11152.pdf">https://www.kohler.com/content/dam/kohler-com-NA/Lifestyle/PDF/PDF-g11152.pdf</a>)</p></div><div><p class="MsoNormal"> </p></div><div><p class="MsoNormal">However, they each say their ATSs must be used with the corresponding generator.</p></div><div><p class="MsoNormal"> </p></div><div><p class="MsoNormal">I would imagine a simple 'grid sense' functionality would mean that if the hybrid's output was connected to the Grid/Normal lugs and the grid was connected to the Gene/Backup lugs in the ATS it should work.</p></div><div><p class="MsoNormal">However I don't want to end up with an expensive surprise in a relatively remote location where I operate!</p></div><div><p class="MsoNormal"> </p></div><div><p class="MsoNormal">Would appreciate any feedback with experience with the above or other ATS models or how people are future proofing for this scenario?<br>To do future maintenance/torque checks etc. in a GT hybrid whole home backup situation, it would be nice to bypass the inverter and keep the house powered for safety and homeowner convenience in general.</p></div><div><p class="MsoNormal"> </p></div><div><p class="MsoNormal">Thanks and best.</p></div><div><p class="MsoNormal"> </p></div><div><div><div><p class="MsoNormal">Sunniest regards,</p><div><p class="MsoNormal">Stuart</p></div><div><p class="MsoNormal">441 599 2105</p></div></div></div></div></div></div></body></html>