I've wanted to find a thermostat that could handle DC Voltage for a while now, but I haven't done the research. What I've wanted to do is to tap right off the PV input, through a thermostat, into a simple resistive heater. That way, it won't drain the battery to warm the array. If the resistive heater is designed for 120V AC, then it should work pretty well with 3 60 cell modules in series. I'd want to actually do the math with the Voc and Vmp and temperatures before suggesting an actual design, but shooting from the hip, If you have 5 or 6 modules in series, then just wire 2 heating pads in series. If you have 10 to 12 modules in series, just put 3 heating pads in series. You get the gist. I think the only difficult part to really figure out is the thermostat. I don't know if anyone makes a thermostat that would work with the DC voltage. Otherwise, you'd need a DC relay or contactor, but then you'd need a source for the control voltage...
Anyways, just some food for thought. If anyone has ideas about a high voltage DC thermostat, I'd love to hear about it. Thanks, Kienan Green-Go Solar Distribution LLC Maxfield Solar LLC (installation and consulting company) maxfieldso...@hotmail.com<mailto:maxfieldso...@hotmail.com> (801) 631-5584 (Cell) ________________________________ From: RE-wrenches <re-wrenches-boun...@lists.re-wrenches.org> on behalf of Chris Schaefer via RE-wrenches <re-wrenches@lists.re-wrenches.org> Sent: Thursday, February 9, 2023 11:01 AM To: RE-wrenches <re-wrenches@lists.re-wrenches.org> Cc: Chris Schaefer <ch...@solarandwindfx.com> Subject: Re: [RE-wrenches] Fortress Battery Heater Ray, I'd suggest reaching out to the Fortress techie's as they just introduced a heater product for their enclosure products. While I don't believe they have a unit specif to the eVault but you should be able to make it work. Christopher On Wed, Feb 8, 2023 at 6:43 PM Jerry Shafer via RE-wrenches <re-wrenches@lists.re-wrenches.org<mailto:re-wrenches@lists.re-wrenches.org>> wrote: Pet heater have worked for me, I air gap a sealed heater box under the battery, thermostat inside the top of the battery. It's slow and low power but does the trick Fun times On Wed, Feb 8, 2023, 3:05 PM Ray Walters via RE-wrenches <re-wrenches@lists.re-wrenches.org<mailto:re-wrenches@lists.re-wrenches.org>> wrote: Hi All; I have a fresh Fortress Evault installation with a Solark inverter. The batteries are indoors in the center of the house, but the customer is not there full time, so the battery is unfortunately going below freezing. What are the best options for setting up a heating system for the E Vault? Here are ideas that I have not tried, but am considering: 1) add a 240 v, 1000 w baseboard heater in the room near the battery that is wired to only run off the generator. Run the generator until the heat comes up, and then hopefully after 30 minutes, the battery would begin accepting a charge. 2) Add an 120 vac heating blanket under the evault that would be wired to a thermostat, but also have a relay control from the PV system, so that the heater would only operate when the sun was out, and the battery was below 50F. I don't quite know how to set this up with the Solark's load controls. I've considered some DC options, but they don't make much sense, since the inverter has to be on to charge from PV anyway. The long term plan is for the client to finish the insulation, and sheet rock, and add a gas wall heater in there as needed. Thanks, Ray Walters Remote Solar in the Colorado mountain cold..... _______________________________________________ List sponsored by Redwood Alliance Pay optional member dues here: http://re-wrenches.org List Address: RE-wrenches@lists.re-wrenches.org<mailto:RE-wrenches@lists.re-wrenches.org> 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/re-wrenches@lists.re-wrenches.org/ 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 _______________________________________________ List sponsored by Redwood Alliance Pay optional member dues here: http://re-wrenches.org List Address: RE-wrenches@lists.re-wrenches.org<mailto:RE-wrenches@lists.re-wrenches.org> 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/re-wrenches@lists.re-wrenches.org/ 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 -- Chris Schaefer’s [http://www.solarandwindfx.com/wp-content/uploads/2015/01/Solar-Wind-FX-Logo.png]<http:www.solarandwindfx.com> Tel/Fax 585-229-2083 or Cell 585-748-1870 5115 South Hill Road ~ Canandaigua New York 14424 www.solarandwindfx.com<http://www.solarandwindfx.com> ~ E-mail: ch...@solarandwindfx.com<mailto:ch...@solarandwindfx.com> [http://solarandwindfx.com/wp-content/uploads/2015/01/certs.jpg] Thomas Jefferson, the author of our great Constitution, once said, "democracy" will cease to exist when you take away from those who are willing to work and give to those who would not."
_______________________________________________ List sponsored by Redwood Alliance Pay optional member dues here: http://re-wrenches.org List Address: RE-wrenches@lists.re-wrenches.org 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/re-wrenches@lists.re-wrenches.org/ 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