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   Hippy Steve (exador23@m.ai6yr.org)'s status on Thursday, 15-Jan-2026 04:44:15 JST Hippy Steve

   So many people in #VanLife groups putting their lives at risk with their #Solar systems. The problem is inverter size vs system voltage. People are running 3500W and even higher wattage inverters on a 12V battery bank. That's 300A of current!! Not only do the wires need to be massive, expensive, and hard to negotiate around curves, but at those current levels you'd need to constantly monitor the torque on the connections and any heat build up in the wires.

   Every connection is going to have some resistance. The higher the current the greater the voltage drop/heat build up through that resistance. This then causes thermal expansion/contraction which will loosen those connections resulting in even higher resistance and heat. Note the positive feedback loop. There's very little room for error at such high current levels. the same process can happen with a poor crimp.

   12V is fine up to 2kW. 24V to 4kW. Anything above that and you should just go 48V.

   • Embed this notice
     Hippy Steve (exador23@m.ai6yr.org)'s status on Thursday, 15-Jan-2026 04:44:13 JST Hippy Steve

     in reply to

     • derptron
     • Dave Mc

     @crazyeddie @guigsy

     I think if I had a medical device and that was the only AC load, I'd consider one of those all-in-one power stations. A small inexpensive one should suffice. They can be recharged with DC from your main batteries. I'd keep the inverter too, but just powered off.

     That way, if your main system went down, or the power station went down, you've still got power for the CPAP. And you can take it with you if your were on a trip or camping or whatnot.

     Steve's Place repeated this.
   • Embed this notice
     AI6YR Ben (ai6yr@m.ai6yr.org)'s status on Thursday, 15-Jan-2026 04:44:13 JST AI6YR Ben

     in reply to

     • derptron
     • Dave Mc

     @exador23 @crazyeddie @guigsy If you are in Southern California (SCE) territory, and in high fire danger areas, SCE will generally pay for a all-in-one power station specifically for CPAP and other medical equipment (if you fill out the right paperwork, of course). I know a lot of people with those (free power stations, large ones, with solar panels) because they are on CPAP.

   • Embed this notice
     derptron (crazyeddie@mastodon.social)'s status on Thursday, 15-Jan-2026 04:44:14 JST derptron

     in reply to

     • Dave Mc

     @guigsy @exador23 Been thinking this is the way to go. I have a CPAP I have an inverter for but I could probably make a USB adapter for it and it'd be happier.

   • Embed this notice
     Dave Mc (guigsy@mstdn.social)'s status on Thursday, 15-Jan-2026 04:44:15 JST Dave Mc

     in reply to

     @exador23 in my (European) van, I don't have an inverter. I've got a 280Ah lithium battery. But I cook and heat with gas. I've got a few USB C PD outlets wired into the 12v battery means I can charge a 15" laptop at 30 watts, which is just enough to slowly gain battery while I'm playing light games. I don't have anything on mains.

   • Embed this notice
     Stephen Hoffman (hoffmanlabs@infosec.exchange)'s status on Friday, 16-Jan-2026 04:47:45 JST Stephen Hoffman

     in reply to

     @exador23 Mmmmmmmmm toasty!

   • Embed this notice
     Hippy Steve (exador23@m.ai6yr.org)'s status on Friday, 16-Jan-2026 04:47:46 JST Hippy Steve

     in reply to

     And here's another one posted today. They're running 3500W at 12v and wondering why this wire is reaching its melting point.

     mark repeated this.
   • Embed this notice
     mark (atleagle@mastodon.online)'s status on Friday, 16-Jan-2026 04:48:38 JST mark

     in reply to

     • Stephen Hoffman

     @HoffmanLabs @exador23 give it a little help and you may have a welder