<div dir="ltr">Appears that Zonna still has quite a few in stock. Feeling foolish to purchase more after having a TS4-2F fail into a pile of molten plastic and ruin a 405 watt bifacial module that I can no longer find a replacement for. What other options do we have for small DC coupled arrays on residential rooftops though? Not the most inspiring times to be installing rooftop PV. Hopefully I'll start having better luck with the single module units. Numerous times I've had units become bricked and not pass module voltage but this is the first time I've had this type of catastrophic failure that also inconveniently cost me the module.<div><br></div><div>Nick</div><div><br></div><div><br></div><div> </div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Mon, Nov 17, 2025 at 7:10 PM William Miller via RE-wrenches <<a href="mailto:re-wrenches@lists.re-wrenches.org" target="_blank">re-wrenches@lists.re-wrenches.org</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div><div lang="EN-US"><div><p class="MsoNormal"><span style="font-size:12pt;font-family:Verdana,"sans-serif"">Friends:</span></p><p class="MsoNormal"><span style="font-size:12pt;font-family:Verdana,"sans-serif""> </span></p><p class="MsoNormal"><span style="font-size:12pt;font-family:Verdana,"sans-serif"">I am having trouble locating these RSDs. Very few vendors appear to have these and I can’t get any to call back and verify they have them. I can’t get Tigo to return my calls. Does anyone know if these are discontinued?</span></p><p class="MsoNormal"><span style="font-size:12pt;font-family:Verdana,"sans-serif""> </span></p><p class="MsoNormal"><span style="font-size:12pt;font-family:Verdana,"sans-serif"">What are the rest of you doing for rapid shutdown? I don’t trust Alps: I have heard too many horror stories. It seems the form factor is too small to contain arc suppression measures.</span></p><p class="MsoNormal"><span style="font-size:12pt;font-family:Verdana,"sans-serif""> </span></p><p class="MsoNormal"><span style="font-size:12pt;font-family:Verdana,"sans-serif"">Somewhere I saw as an alternative the Tigo TS4-A-O. These are optimizers. I worry these will fight with the MPPT algorithm in the inverter or charge controller. There is also the TS4-A-S which has shutdown and monitoring.</span></p><p class="MsoNormal"><span style="font-size:12pt;font-family:Verdana,"sans-serif""> </span></p><p class="MsoNormal"><span style="font-size:12pt;font-family:Verdana,"sans-serif"">All input is welcome an appreciated. Thanks in advance.</span></p><p class="MsoNormal"><span style="font-size:12pt;font-family:Verdana,"sans-serif""> </span></p><p class="MsoNormal"><span style="font-size:12pt;font-family:Verdana,"sans-serif"">William</span></p><p class="MsoNormal"><span style="font-size:12pt;font-family:Verdana,"sans-serif""> </span></p><p class="MsoNormal"><span style="font-size:12pt;font-family:Arial,"sans-serif"">Miller Solar</span></p><p class="MsoNormal"><span style="font-size:12pt;font-family:Arial,"sans-serif"">17395 Oak Road, Atascadero, CA 93422</span></p><p class="MsoNormal"><span style="font-size:12pt;font-family:Arial,"sans-serif"">805-438-5600</span></p><p class="MsoNormal"><span style="font-size:12pt;font-family:Arial,"sans-serif""><a href="http://www.millersolar.com/" target="_blank">www.millersolar.com</a></span></p><p class="MsoNormal"><span style="font-size:12pt;font-family:Arial,"sans-serif"">CA Lic. 773985</span></p><p class="MsoNormal"> </p><p class="MsoNormal"> </p></div></div>
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