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Outdoor 2-gang box with 5-15 + something 240V

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Like many others here I'm sure, I frequently visit family with limited charging options. I've made myself a 14-30 to 10-30r cable that I use to charge from dryer outlets. It's been a life saver. But, I'm interested in a more permanent and less janky solution.

I don't think this house has capacity for a 50amp circuit. It does already have an outdoor duplex 5-15. I'd also really prefer to keep the visible changes to a minimum. My home base is Boston, but family are in Montreal, Canada.

What I was thinking was I'd enlarge the outdoor box to a 2-gang, and install a 1-gang sized L6-15/20/30 (depending on what the panel can accommodate) along side the dual 5-15.

I fully intend on having an electrician do the work. But, I know there are some knowledgeable folks here, and perhaps I can get an answer quicker ;)

Can I put 250 and 125 receptacles in the same electrical box?
What would the box size requirements be for these configurations? Will a standard 2-gang box be ok?
Anyone know of a nice outdoor 2-gang box that could fit a single L6-20/30 + GFCI 5-15?
 
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Interesting. I just got (or at least I think I got) the opposite answer.

I just added a 14-50 outlet in the garage, and while we were crawling under the house stringing wires, decided to throw in a pair of duplex 20 amp 120v outlets too. So, one run of #4-3, and one of 12-3. I did most of the mechanical work, to save labor cost, and asked if I could put the pair of 20's and the 14-50 in the same box, and the electrician said no. Not sure why, but I think it was because there aren't any cover plates with that combination of outlets.

In hindsight, having two boxes was really the right answer, from a practical matter. The high current wires are so stiff to work with, having anything else in the box would have been more than annoying.
 
A 14-50 just wouldn't physically fit along side a 5-15 receptacle in a duplex box. It is too big.

Why would you use a locking 240v? Why not just a regular 6-15, 6-20 or 6-30?

I don't know what the codes would say about outdoor 6-20 or whatever receptacles. A normal receptacle would need to be gfci protected, but probably not a 240v one?
 
You won't be able to find any plates for that combo. You should be able to find one for a 6-20 to go with a 5-20 duplex. Then get/make an adapter cable to 14-50 and you'll be set up for reasonably quick charging.

Duplex/Single Receptacle - Platt Electric Supply

Those exist. Ones for a larger locking outlet won't exist. An L6-20 comes in at 1.56 inches, too big for that plate. A 6-20 is perfect at 1.37 inches.
 
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There are some differences in the National Electric Code (NEC) and Canadian Electric code (CEC); and differences in CEC by province. I believe you are installing this in Montreal, correct? If so perhaps @llavalle or some others from the Quebec Tesla Club club-tesla-quebec could give you a better answer.....

I don't have a definitive answer for you - code wise - but I've seen a L6-30R installed alongside a 5-15 with a custom wall plate. This was done inside of a garage, by a licensed electrician in Quebec, Canada. Not sure if it was to code but it was from a reputable company. It was done using 2 of those. Sharing a plate on the outside but inside the wall, each side was isolated. Since the install was inside, no GFI needed - an no special needs for a cover.

If the GFI requirement is the problem in you specific case, keep in mind that if you install the outlet high enough above finished grade, you don't need one. (not sure if practical) ref : 86.306, section 2.
The receptacle in Subrule (1)(a) shall be protected with a ground fault circuit interrupter of the Class A type, when the receptacle is installed outdoors and within 2.5 m of finished grade.

Also worth mentioning, you could simply install a 5-20 in place of the 5-15 (with the correct, upgraded wiring). Charging at 1920W(16amps) instead of 1440W (12amps). With the basic load of charging (coolant pumps, etc), it makes a huge difference. Clearly not as fast as 240V@24amps but it might do the trick.
 
You can do this with a 14-50, or ??

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Parts from Home Depot/amazon