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NEMA 5-20 to 14-30 for 15A level 2 EVSE?

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My twin brother and I have been displaced by a deadly EF-4 tornado. I was injured and my car was crushed, putting more burden than ever on my bro’s car that he can no longer keep charged (no garage or even a driveway at the temporary home). It doesn’t help that it takes Premium gas and prices temporarily doubled with the recent pipeline hack.

We’ll never be able to return to our basement workshop/lab so we are trying to resume operations in a rented place where I found the hard way that this NEMA 5-20 outlet was wired for 220v:

Yeah, it fried some equipment. No, it wasn’t hanging out like that but it was surrounded by webs and had no wall plate. The temporary home uses nothing but these same 5-20 outlets wired to 120v so I didn’t have any reason to suspect it was 220v here. Just yesterday I knocked out the boarded up window to install that window-unit AC and might’ve grabbed a more-efficient 220v unit if I had known sooner!

To make lemons from lemonade, I’d like to use the 220v outlet to charge my brother’s car while at the workshop. Heck, I might even have to stay in the workshop until I find a place since the landlord plans to sell once the home is rebuilt. My bro has a 220v Level 2 EVSE and the Volt can only charge at 15A:


It seems these outlets can easily handle it and even GM recommends a 20A socket. My only remaining concern would be others trying to use it for a higher-amperage car. I can’t share our electricity anyway so I will 3D print an outdoor EVSE mount and rig up a lock of some kind.

My remaining questions are:
-Is it OK to use an adapter for NEMA 5-20 to 14-30 as long as I am staying under 15A?
-Should I instead grab my NEMA 14-30 socket from the tornado-damaged home and install it here? Guess I should remove the breaker or cap the wires (wire nuts?) if we go that route.

We had help from an electrician friend when installing this one in the old place’s garage and he’s now out of state so I don’t trust my limited experience without someone telling me exactly what wires go where, especially in this rotting workshop. Yes, that is daylight you see inside the walls there. Damned tornado.

If you're sure it won't pull more than 15 amps what I would do is install the NEMA 6-20R that should be there and make up a pigtail to adapt to 14-30, I'll hazard a guess it doesn't use the neutral connection and you can leave that floating. That's probably the closest to legal option, don't put a 14-30 in that box, the cable feeding it is likely only 3 conductors (two lives to provide the 240 and a ground), not 4 with a proper dedicated neutral.

Thank you. The Chevy Volt draws under 15A even on a Level 2 EVSE rated for more so we are good there. Good call on the 6-20R... when I googled 5-20R 220v before I found results suggesting that people were using it for 220v air conditioners and not just 20A 120v AC units. Scary and definitely needs to be fixed/changed to 6-20R.

I checked and you are right: the cabling does not have a neutral. The building is one-room cinderblock with direct access to the rafters above the outlet and breaker box so I may just run four conductors with the 14-30R outlet and a new breaker. That breaker box looks like it came from WWII era and I really don’t know what I’ll be getting into with it so I am still looking into pigtails. A seller on Amazon makes these two:

Supposedly they are both 6-20P to 14-30R but what’s strange about the second one is that they show a 5-20P on the first pic. The other pics show 6-20P as they should but if that’s what you get then I still have to wonder why the same seller has two listings for the same thing. Weird... and also weird that the one in the picture would seemingly adapt my strange 220v 5-20R socket that I shouldn’t be able to adapt without swapping for a 6-20R! Not that I would do that. If I use an adapter at all it will be for a 6-20R outlet as you suggest.

Thanks for your help.

For $60 I'd make my own pigtail, Home Depot or wherever will have the parts and suitable cable by the foot, likely under $30 in parts.

Yeah, I still plan to but I’ve been trying to get to a hardware store for days and it just isn’t happening soon. The very transportation situation this is meant to help with just isn’t allowing it yet. Thought I would start some comparison-shopping in the mean time. ;) Thanks again!


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