We have a multitude of these same issues with the TS40-A-F. We followed every new guideline from Tigo in order to avoid corrupted signals but still had issues. After a hot breezy day in NJ last year caused a Tigo failure to spread the roof caught on fire and caused millions in damage. Thankfully no one was injured. We spent the rest of 2024 pulling 6 MW's of Tigos off of other roofs for this customer. I have heard multiple stories of similar issues for many very experienced installers.
David Buckner SES ________________________________ From: RE-wrenches <[email protected]> on behalf of Nick Lucchese via RE-wrenches <[email protected]> Sent: Wednesday, November 19, 2025 12:11 PM To: [email protected] <[email protected]>; RE-wrenches <[email protected]> Cc: Nick Lucchese <[email protected]> Subject: Re: [RE-wrenches] Tigo TS4-A-F CAUTION: External Email. 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. Nick On Mon, Nov 17, 2025 at 7:10 PM William Miller via RE-wrenches <[email protected]<mailto:[email protected]>> wrote: Friends: 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? 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. 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. All input is welcome an appreciated. Thanks in advance. William Miller Solar 17395 Oak Road, Atascadero, CA 93422 805-438-5600 www.millersolar.com<http://www.millersolar.com/> CA Lic. 773985 _______________________________________________ List sponsored by Redwood Alliance Pay optional member dues here: http://re-wrenches.org<http://re-wrenches.org/> List Address: [email protected]<mailto:[email protected]> Change listserver email address & settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org There are two list archives for searching. When one doesn't work, try the other: https://www.mail-archive.com/[email protected]/ http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules & etiquette: http://www.re-wrenches.org/etiquette.htm Check out or update participant bios: http://www.members.re-wrenches.org<http://www.members.re-wrenches.org/>
_______________________________________________ List sponsored by Redwood Alliance Pay optional member dues here: http://re-wrenches.org List Address: [email protected] Change listserver email address & settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org There are two list archives for searching. When one doesn't work, try the other: https://www.mail-archive.com/[email protected]/ http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules & etiquette: http://www.re-wrenches.org/etiquette.htm Check out or update participant bios: http://www.members.re-wrenches.org

