Multiple 240V outlets on a single circuit is a code violation.
A 14-30 on a 50A breaker is a code violation.
A 14-50 on a 30A breaker is a code violation.
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A 14-30 on a 50A breaker is a code violation.
A 14-50 on a 30A breaker is a code violation.
deonb
Active Member
Definitely NOT a code violation, and commonly done in workshops where you have 240V power tools that you'd like to move around. Because 240V however is otherwise a bit specialized, there are other codes that come into place when you have hardwired and/or semi-hardwared appliances in place, like ovens and dryers. But for a general purpose outlet, there is nothing special about the branch circuit code (210.23) that deals with 110V vs. 240V differently.
I can pretty much guarantee you that if you have a good use case for two 14-50 outlets where you obviously only used 1 of them at a time, that you can put both of them on one branch circuit. E.g. a single car garage where you want to sometimes pull in nose first, and sometimes back in, so you want a 14-50 outlet on each wall. (Definitely allowed with 6-50, 99% sure it's allowed with 14-50 as well).
Of course, but this is outright unsafe.
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I think you're referring to 210.21 here, and though it may be technically true (though I think 210.21 technically refers to the actual load and not the capacity of the outlet), I don't think it's a safety issue as much as a user expectation issue.
Case and point, the typical 15A outlet has 2 sockets. It would be entirely possible to plug a 12A appliance into each of the 2 sockets. And it won't work since you're trying to draw 24A from a 20A circuit.
If this was an egregious safety issue, code would have called for there to be one, and only one socket (not even outlet, but socket) on a single circuit. It doesn't.
Either way, whether or not this exist as code wasn't the issue - the issue was whether it was unsafe vs. inconvenient. I maintain it's no more unsafe than a branch circuit or 2 sockets on one outlet.
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Fair enough - after some digging, I'll retract the multiple outlets comment (or more accurately, "receptacle"). There's definitely some caveats around multiple "outlets" (separate equipment connections) at other points in the code (ie, 430 - motors, etc)
210.21(B)(3) seems pretty clear to me - a 50A circuit needs a 50A outlet, and a 30A circuit needs a 30A outlet.
Why would you put in a 30A circuit, then a 50A outlet, use a 14-50 UMC adapter, and have to manually dial down the current (and check to make sure it hasn't reset)? Safe or not, legal or not, code violation or not, it's just a dumb thing to do. Do it right, put in a 14-30, and spend the $45 on the 14-30 adapter. If someone can afford the car, the $45 adapter won't break the bank...
And I pointed out it violated NEC. Besides, what's the point? We're both being sort of pedantic, anyway.
Those are high prices to put in outlets. I know each situation is different, but the fundamentals are the same. I put two NEMA 14-50 plugs into my garage, and I have only general electrical knowledge. I had an electrician check my work at a later time and it was good to go. Everything is to code. 150ft of 6ga wire was $400, another $100 for everything else. It took a few hours. I put one outlet on each one of my 200a panels. I wouldn't have done it if I had to upgrade the panel though. The quotes I received were around $1300-2200. Hourly rate of $200-400? Highway robbery.
brucet999
Active Member
As others have said, there is no way to "upgrade" your 120V outlet to 30A 240V. The 12 AWG wires that are likely there will not support more than 20A. If someone went cheap and wired with 14 AWG, then the best you can have is 15A. What you CAN do with the present wires is upgrade to either 15A 240V or 20A 240V, depending on wire size.
One complication might be that your existing outlet is one of several on the same circuit. If so, then changing one outlet to 240 may force you to make them all 240 if the one you want to covert is last in line on the branch circuit. Whatever is downstream of the converted one can still be wired 120V, but anything upstream must be blanked off or converted to 240V
Fortunately for you, Chicago electrical unions' political power made metal conduit mandatory for many years (perhaps still) so you probably have conduit going back to your service entrance panel. If it is large enough conduit, you can pull out the old wires and pull new wires big enough for your charging port:
30A 240V needs 10 AWG solid copper wires, which will fit easily inside a 3/4" conduit (a likely size for an existing 12 AWG circuit) and you can install a NEMA 14-30 dryer outlet in a new 4" box. There is a 14-30 adapter available (again) from Tesla that automatically restricts charge rate to 24A and enables you charge at 5.7kW, enough to charge my S70 from 10% SOC to 90% SOC in about 9 hours.
50A 240 needs minimum 8 AWG THHN copper wires and that would be a snug fit in 3/4" conduit; doable if there are no tight bends and not too many 90º bends altogether, and with a lot of wire-pulling lube. That would have you charging at 9.6 kW, capable of charging my S70 from 10% SOC to 90% SOC in about 5 hours.
Of course, if the panel is in, or near to, the garage, a whole new conduit could be pulled to your desired charging outlet location.
gavine
Petrol Head turned EV Enthusiast
A DIY option to save money for those who are uncomfortable wiring-up breakers and outlets, why not buy the wire (appropriately sized of course), and run it yourself?...just from the breaker panel to the outlet. You'll save a ton of labor costs vs. the electrician running the wire. Just pay the electrician to bring the wire into the boxes and connect to the breaker and outlet. You're actually doing all of the hard work. Connecting wires is the easy part.
The longer the run, the more you'll save.
The longer the run, the more you'll save.
deonb
Active Member
In that case you can argue by buying a perfectly good UL Listed product and plugging it into an outlet, and have the breaker trip out because of other unrelated (but also perfectly good) items plugged into other outlets that were not known to be on the same branch, is also not meeting user expectations, and is also inconvenient.
I feel as if everybody forgot what it was like to own 1000W desktop computers... Actually, even my laptop now has dual 450W power supplies, so they're getting up there.
Some electricians won't agree to that, or even to use customer-supplied parts/wire. If someone wants to go that route, make sure you have buy in from your electrician before doing all that work yourself.
Well, yeah... That has me thinking - I once lived in a house where the sellers had installed a stacked washer/dryer on the main floor after the elderly resident couldn't manage the stairs to the basement laundry. The installers daisy-chained the new main floor dryer off the basement dryer outlet. I assumed it was not inspected and wouldn't pass, but now you have me reconsidering. Guess I'll dig through the NEC and see what I find.But that's what we DO on TMC!
ElectricTundra
P85D AP1
Where do you plan to get a neutral from for those downstream 120v?
OP, make sure your electrician knows that this is a constant current use and so wiring must be sized for 25% larger. E.G., you can only do 16a on 12ga, not 20a. Also, if you're tight on funds, you may be OK with your current outlet. You can likely get 4+ MPH out of it so 48 miles for 12 hrs overnight or a bit more if you can plug it in longer. A larger circuit for faster charging is nice but not necessary for many people.
Multiple 240v outlets on a single circuit is quite common in wood and metal shops. Similarly, it's not unusual to see a 14-50 on a circuit wired and breakered for 30a. Wiring, outlet, and load can always be bigger than the breaker, but never smaller.
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brucet999
Active Member
Oops. You got me there. That only works if the multiple outlets had been on a three-wire circuit as my garage was.
