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Is NEMA 14-50 AND Tesla Wall Connector a good idea?

Does anyone install Tesla Wall Connector AND NEMA 14-50 (or 6-50) outlet? Seems that this would either require 100A total dedicated current from breaker box OR somehow add a NEMA plug to the Tesla Wall Connector so that we have to go through the NEMA plug regardless. My electrician was saying this is what some people do but maybe there was a misunderstanding?

Is it relatively easy to convert TWC to NEMA 14-50 and vice-versa ? Seems like it is from what I've read.

Thank you!
 
Actually a 14-50 limits you to 40A of charging (80% of capacity for continuous loads, and EV charging is a continuous load), and isn't really future proof in that sense. Most future proof is to run a cable that can handle 100A (80A continuous) because J1772 supports up to 80A of charging, and some vehicles like old Model S vehicles with dual OBCs, Rivians, and Lucids do have 80A OBCs in their vehicles. Modern Tesla vehicles use a 48A OBC (except the Model 3 standard range which has a 32A OBC), so the 14-50 won't let you charge at full capacity.
A MY only charges at 32 amps when plugged in to a 14-50 receptacle on a 50 amp breaker.
 
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A MY only charges at 32 amps when plugged in to a 14-50 receptacle on a 50 amp breaker.
Not true. Every MY has a 48A OBC, and can charge at up to 40A when powered by a 14-50 outlet with a EVSE that's capable of supplying 40A. The 32A limitation is on the Gen 2 Mobile Connector but is not inherent to the outlet itself and what electrical code dictates you can pull from it. And the statement that you cannot ever get the full 48A from a 14-50 outlet is true no matter what EVSE you are using.
 
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Thank you again everyone - I'm learning a lot here.

Yeah I would think the hardest thing to install is the wiring because that requires conduit, painting, attic access. So I think if I have them run the 4 wires (2 hot, neu, gnd) with 6AWG that covers 50A. However, I don't think 6 AWG would be enough to cover potential upgrade to 100A (about 30 ft run, up from breaker to attic, across attic, down to either TWC or outlet). From what I'm reading it looks like 1 or 2 AWG would probably be required to potentially support 100A which is probably a big added cost.
 
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SageBrush

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I don't think 6 AWG would be enough to cover potential upgrade to 100A (about 30 ft run, up from breaker to attic, across attic, down to either TWC or outlet)

IIRC, an 100 Amp sub-panel would require a 70 Amp feeder to meet NEC load requirements. That would be a #4 AWG presuming NMC cable, but I personally would choose #3 AWG to err on the safe side.

The biggest problem I see with thinking about combining a 14-50 receptacle with a wall connector is that power sharing is not possible. You are stuck if the receptacle is for uses other than EV charging, but if two EVs charging is the goal, then ditch the 14-50 and install two power sharing devices connected to a 60 Amp breaker in the main panel with #6 AWG. That will provide about 460 EPA charging miles a 10 hour night to split between the cars.
 
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I've been charging my cars since 2002. I've only, EVER used a 220-volt outlet, with the wall connector now with the Tesla. I never could figure why ANYONE would need a $400 box to charge their car when a ten-dollar box would do the same job, both overnight, both reliable. But, if someone wants to spend more, go for it! My cars still run, charged mostly with my garage outlet and the wall connector, and occasionally by supercharger when on trips. The car charges full every morning after a night of slow 220-volt charging.

I can understand that some folk can't plan that far ahead and need to charge in the middle of the day, immediately, to make it -- somewhere -- quick!!!, rather than planning for the day's needs the night before. I guess I'm a planner.
 
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RoBoRaT

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Nov 22, 2018
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Does anyone install Tesla Wall Connector AND NEMA 14-50 (or 6-50) outlet? Seems that this would either require 100A total dedicated current from breaker box OR somehow add a NEMA plug to the Tesla Wall Connector so that we have to go through the NEMA plug regardless. My electrician was saying this is what some people do but maybe there was a misunderstanding?

Is it relatively easy to convert TWC to NEMA 14-50 and vice-versa ? Seems like it is from what I've read.

Thank you!
My neighbor OP - in case you are looking for Gen 3 WC, here is my shameless "plug" FS:
:p

 
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I've been charging my cars since 2002. I've only, EVER used a 220-volt outlet, with the wall connector now with the Tesla. I never could figure why ANYONE would need a $400 box to charge their car when a ten-dollar box would do the same job, both overnight, both reliable.
Penny wise, pound foolish. If that $10 outlet ever catches fire because the half prongs don't grip the plug as well as they used to and it overheats and ignites something, you're going to pay a hell of a lot more than the $40-80 difference between that outlet and the Bryant or Hubbell. You're already saving a ton of money by doing the install yourself but skimping on the cost of the outlet is just foolish when the result could easily be a destroyed plug, a fire, or both.
 
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Don't mess with outlets, just install a wall charger and someday if you move you can take it and cap off the wiring if you want. But you probably won't - that old charger won't be worth the cost of relocating it by that point.

For multiple charging locations you can run 100A or whatever to a subpanel and then break it out to each location but it's likely cheaper to just run multiple ~60A circuits directly from your main breaker panel. And very few people actually benefit from the full 60A circuit and 11kW charge rate, most wouldn't even notice the difference between that and the cheapest 20A (4kW) circuit with plain old 12/2 Romex. Overnight is overnight, and even 4kW on a short 10-hour night will still get you 40kWh which is 50% of the car's capacity and ample for most commutes.
 
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Does anyone install Tesla Wall Connector AND NEMA 14-50 (or 6-50) outlet? Seems that this would either require 100A total dedicated current from breaker box OR somehow add a NEMA plug to the Tesla Wall Connector so that we have to go through the NEMA plug regardless. My electrician was saying this is what some people do but maybe there was a misunderstanding?

Is it relatively easy to convert TWC to NEMA 14-50 and vice-versa ? Seems like it is from what I've read.

Thank you!
220 dryer plug 30 amp and usually charge at 26 A. If I charge overnight I’m fully charged the next morning. Only cost was the extension cord. I love it!
 
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220 dryer plug 30 amp and usually charge at 26 A. If I charge overnight I’m fully charged the next morning. Only cost was the extension cord. I love it!
Uh...that's against code. You're only supposed to be able to go up to 24A on a 30A outlet and that's supposed to be enforced by the EVSE.
 
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Charging an EV is not like running the dryer for 45 minutes to dry your clothes. I have a Sense energy monitor and I can see that my dyer on 'high' uses about 7kw of power. But it is not always 'on' it can cycle off and on as the internal temp warms and cools. The car however can pull 32 amps (I have a RWD) for hours and hours. Don't mess with substandard components. For my 14-50 I ran #6 wire to add margin and used a Hubble receptacle. And the Tesla Wall Connector is limited to 32 amps when I set it up. That's all my car will do anyway, but even if my car could go to 40 amps I can't ever see the need to charge are that rate. In fact I don't even charge at 32 amps, I normally dial it back.

While I installed the wire and outlet, I had an electrician land it in the subpanel. The first time I charged at 32 amps I noticed after about 2-3 hrs the car stopped charging. I couldn't figure out why. I checked the breaker and it had tripped. I didn't check it right away, it was a few hours after it tripped. I reset the breaker and re-started the charging. Eventually the same thing happened. This time I quickly checked the breaker and it must have been around 200 F. It did the job, it tripped at a high temperature. The electrician had installed a cheap breaker, whatever he had on the truck. Didn't make the panel brand (should not have to as long as they were compatible.) However, this could have caught the circuit box on fire. I bought a new breaker with the matching brand and it fixed the problem. Tossed the bad breaker.

There is a YouTube video from Munro and Associates that talks about this problem. I can't imagine spending $50K on and EV and skimping on the outlet to save <$100.

An easy test is to just touch all the components of your charging hardware, the plug, wire, outlet, cable, breaker, after it has been running for a few hours. Anything that is more than warm needs to be checked out. Maybe the wires aren't fully seated or torqued, maybe the breaker is the wrong type, or the bus bars were corroded, maybe a wire is under sized.

 
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Not true. Every MY has a 48A OBC, and can charge at up to 40A when powered by a 14-50 outlet with a EVSE that's capable of supplying 40A. The 32A limitation is on the Gen 2 Mobile Connector but is not inherent to the outlet itself and what electrical code dictates you can pull from it. And the statement that you cannot ever get the full 48A from a 14-50 outlet is true no matter what EVSE you are using.
Well I plug my model y into a 14-50 plug every day using the mobile connector supplied by Tesla and the 14-50 adapter and it draws a max of 32A. If you can tell me how to get more charging power out of that setup I would be forever in your debt.
 
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