That will work. It'll just limit to 12a because of the plug. The plug is fine for 240v even in that case.
240v charging from two 120v receptacles
- Thread starter factorytuned2012
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What do you mean? 208 is three phase power. 240 is single phase. If you you have two hots you will have 240 from a typical house panel. It appears that this device is just a fancy junction of the two hots.
Please clarify what you are saying, as I am interested in learning something new.
This is common among Prius Prime owners... the US EVSE is the same as the one they use in 240 volt land except for the plug. Change or adapt the plug and the car can charge with 240. Remember the EVSE is just a dumb relay box; the charging is part of the car.
The face of the duplex they showed is only good for 15 amps. It lacks the little "winky" horizontal slot. If it were intended for 20 amp circuits only they'd have put two winky male plugs on it. (NEMA 5-20P.) That's the mechanical interface to keep stupid people from doing stupid things.
8 amps of 120V plus 8 amps of -120V is 8 amps of 240V.
The EVSE shouldn't use the neutral or ground during normal operations. Many have 3-prong plugs so there shouldn't be current on the third unless there's a fault.
Yup. I think a visual aid might be helpful since most people have seen them even if they don't know what it means.
https://store.leviton.com/collectio...ex-receptacle-residential-grade-white-t5825-w
And then what a NEMA 5-20 plug looks like.
I've never seen a single phase transformer on a residential application with a secondary voltage of 208v phase to phase . If there is such an animal I would be interested in seeing that myself .
Thank you for posting this. I would pull out my Tesla EVSE and take pictures of the adaptors to explain what I meant, but it's cold and I'd be bringing them inside my hotel room to lay them out on my bed to take pictures. The above 5-20 and the variations of the 5-15, 14-30, and 14-50 are similar other than their pinouts and the physical plug that goes into the EVSE or Mobile Charger as it is known which the EVSE knows what it's possible input is based on these plugs. This is why I have a concern about aftermarket adaptors that go on the end of these plugs and other work arounds for faster charging for end users that don't understand the limitations for their chosen charging method. Standard outlets and specific adaptors take a lot of the guesswork out of it.Yup. I think a visual aid might be helpful since most people have seen them even if they don't know what it means.
https://store.leviton.com/collectio...ex-receptacle-residential-grade-white-t5825-w
And then what a NEMA 5-20 plug looks like.
His statement was not correct. The peaks are 180 degrees apart in a residential 120/240 service. 120 degrees in 3-phase 208/120 which is commercial.
I agree. Maybe we was assuming 3 phase power, but in the context of the topic, it was incorrect.
I was thinking I was off my rocker being as many had agreed. Been to many a jobsite and never saw 3 phase in a house....well ran to the house. I have seen 3 phase in a house, but not from the service.
Yeah I saw it once too, years ago in a house owned by a guy that was a serious hobbyist. The same guy also built a submarine in his basement.
Fair to say it's next level.
Regardless of the setup, I have heard some who believe that any outlet used for EV charging should be commercial/spec grade. I've bought a few and have seen the teardowns. At least with 110-120V I haven't seen anything where screw posts are terribly different, but the design of the blade contacts and the receptacle body can be very different. Mostly the way the contacts are formed, where cheaper ones tend to be a U shape, while higher spec have a different shape that's supposed to be less prone to weakening. I've seen some older outlets where the outlet got really loose over time.
The biggest thing to keep in mind with these outlets is that even with a mobile charger is to not constantly unplug and plug it back in. They were designed for appliances to be plugged into for years at a time. Get the highest quality outlet you can find and leave it plugged in. I only have a 30a supply for my garage so I went with a 14-30 and I leave my EVSE plugged in at all times. This means 24a and I usually leave it at 20a for my needs. If it wasn't enough to meet my needs I'd upgrade the power supply and install a Tesla Home Charger. I have a backup EVSE with all associated parts if anything failed and a Tesla branded one in my car for use anywhere if I would get stuck somewhere. I'm a prepper level EV driver. I've not had a problem, but I don't want to chance it.
Wow. A submarine! Why not?
I have seen 3 phase it in a shop (from a convertor) for a giant Tannewitz bandsaw for cutting cedar logs, and in an elevator in a house....again from a convertor.
But even with a convertor, is converted 3 phase just as "good"?
Define " just as good " . What parameters are you measuring ?
Depends. Obviously there are a lot of electronics that are plugged but rarely removed, such as refrigerators, dishwashers, washing machines, TVs, etc. But also things like wall warts that are removed often. There are applications where it's assumed there's going to be frequent plugging and unplugging, like on a train, in an airport, tableside restaurant/cafe outlets, etc. and those need to use more robust commercial receptacles. This shows the difference between a Leviton residential grade vs a spec grade. The spec grade has a better backwire clamp (where the screws are used rather than a barb) and has "triple-wipe contacts" over a basic U shape.
https://hackaday.com/2018/05/14/the-electrical-outlet-and-how-it-got-that-way/
Tesla's Mobile Connector was primarily meant for taking on the road, but as the cheapest charging option (and I guess it used to be included with purchase) I'd think that's the way most Tesla owners charge at home. Used as originally intended, it would be frequently plugged and unplugged. It's not really all that bad for 120V commercial/spec grade outlets. But residential/contractor-grade outlets are another matter. I've replaced a few where the connection got really weak. Even where I'd think the plug was rarely removed over 25 years, like with a power strip. I think the connector just splayed out just by being in the same position all that time. But I've seen some 60 year old spec-grade outlets that were in great shape, but replaced those with GFCI receptacles. Pretty much every GFCI outlet available is spec grade.
A loose receptacle is a fire risk, especially when there are higher current devices plugged in. That's the biggest issue with push-in backwire connections. I remember 30 years ago there used to be backwire connections that could accept 14 or 12 AWG backwire, but now the holes are only for 14. I believe 12 tended to weaken more after time. Still - I've gone through a house and redid every backwire connection (receptacles and switches) to side screws.
that is why is was in quotations....as in ....." is just as good a thing"
i read that a convertor will provide adequate power, but not as efficiently as actual 3 phase, and that some machines would have the warranty voided if a convertor was used.......wondering why that might be....
it is off topic though
I have a carpenter friend who lives a ways from the road and has one of those converters for a table saw. His is essentially just a single phase motor connected to a three-phase generator (I believe in the same housing) so yeah the output would be indistinguishable from utility supplied 3-phase. But large single phase motors are expensive so the converter was too. But it was cheaper than having the utility run new wires to his shop.
You’re right about it not being as efficient though and it takes a lot of power. When he runs that particular table saw he cannot run some other machines at the same time.
That make sense. Thanks. I guess it still boils down to work over time.
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Is the generator providing 3 phase delta or wye? For running heavy loads like motors and heating elements a delta would be more efficient. Generators are also not constant like utility power with rpm fluctuations power output and hz will also fluctuate.
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