Hacker News new | ask | show | jobs
by linsomniac 5 days ago
As I understand it, the US is mostly waiting for UL listing of equipment, which hasn't been a priority because no US locals have allowed them. With Utah and others starting to allow them, UL listing will likely come at some point (hopefully shortly) thereafter.

There's this device: https://usa.apsystems.com/ez1-installers/

And also this: https://connectder.com/

3 comments

State plug in solar legislation tracker: https://www.brightsaver.org/legislation-tracker

(passed in 10 states, 2 awaiting signatures, as of this comment)

If I understand the devices correctly, the current generation of microinverters should meet all power-limit requirements and disconnect if the grid goes away.
You’re correct, but states are looking for UL 3700 compliance, which extends current anti islanding inverter protection requirements to GFCI intelligence and circuit overload protection (you can overload the branch circuit without the breaker tripping, for example). Intelligent EV chargers support these protections, this is the generation version of protections mentioned.

https://electrek.co/2026/07/20/us-first-ul-3700-balcony-sola...

https://pluginsolarus.com/learn/ul-3700-safety-standard-expl...

https://permitpower.org/wp-content/uploads/sites/35/2026/01/...

https://www.cesa.org/wp-content/uploads/Plug-In-Solar.pdf

Thanks for the links. I hope they don't make it difficult to add batteries to these systems. You can pick up five plus kilowatt rack mount batteries relatively cheaply. It would be unpleasant if they only permitted the expensive no-user-serviceable-parts battery boxes like jackery.
Hoymiles just got UL3700 approved this week and sold by Bright Savers
Looks like that system uses the "AP Systems EZ1" microinverter I mentioned above. Their "latest news" page lists UL 3700 with a date of about a week ago, so it looks like they've gotten it.