Charging hookup questions...

[Trebor Srevlis]

I am preparing for a new Tesla. My home has three 150 A main circuits for 450A total (I have three panels, with 150A main breaker on each one). I would like to hire an electrician to put in 2 gauge copper wire to my garage with a 100 amp breaker. I have a few questions.

If I use a Tesla Wall Connector, are those typically wired directly to the wire to the panel, or do people wire the Wall Connector to a NEMA 14-50 plug, and then plug it into a NEMA 14-50 outlet?

Those receptacles are rated for 50A, so I believe that means that I could not use a 100A breaker, and would need a 50A one. If so, is there a connector that is rated for 100A? I see some ones on Amazon that are 100A, but they are like $600 for plug and socket. Or I guess people just wire the Wall Connector directly to the wire to the panel?

So when people talk about NEMA 14-50 receptacles, does that mean they are not using a Tesla Wall Connector and just plug the car directly into the NEMA 14-50 because the cars have on-board chargers? And if so, is that slower charging than if they use the Tesla Wall Connector directly wired to a 100 Amp breaker?

And finally, do people ever use another brand of wall charger with Teslas? And if so, do any have faster charge rates without being much more expensive? I read there are some that have adapters and can charge many brands of cars.

 

[Tdreamer]

The Tesla Wall Connector is usually hard-wired back to the panel. I believe current Tesla models have a maximum onboard charging capacity of 48A for level-2 chargers (including the Tesla Wall Connector), so using a breaker larger than 60A isn't really needed. The exception being if you have an older Tesla that has a 72A onboard charger (my Sept '17 X100D has the 72A onboard charger for example).

If you charge regularly at home, then installing the Tesla Wall Connector is probably a good idea. If you charge infrequently, you could just have a NEMA 14-50 outlet installed, and use the mobile connector that come with the car (keeping in mind, I believe it only charges at a 32A maximum). I'm told the Tesla Wall Connector is well priced when compared to other EV charging solutions. I didn't shop around when I got mine installed.

 

[kkillebrew]

Plugging a wall connector into a NEMA 14-50, or any outlet is not efficient use of the that particular charger, which will charge at 48 to 80 amps when direct connected without a plug. Some electricians can correct me but I believe the limit for a 14-50 is under 48 amps.

 

[Trebor Srevlis]

Ok. So sounds like I want a Wall Connector directly wired to the panel.

And I want to use 2 gauge wire to make it more future proof.

And it can supposedly charge at up to 80 amps, which would mean I need a 100 amp breaker.

Has there been any talk of a 3rd generation Wall Connector? I won't have the car for a while, so I could do everything else and put in the latest Wall Connector at the last minute.

 

[ReddykwRun]

Plugging a wall connector into a NEMA 14-50, or any outlet is not efficient use of that particular charger, which will charge at 48 to 80 amps when direct connection without a plug. Some electricians can correct me but I believe the limit for a 14-50 is under 48 amps.

Yep, 20% less for continuous service rating rule.

 

[ReddykwRun]

I am preparing for a new Tesla. My home has three 150 A main circuits for 450A total (I have three panels, with 150A main breaker on each one). I would like to hire an electrician to put in 2 gauge copper wire to my garage with a 100 amp breaker. I have a few questions.

If I use a Tesla Wall Connector, are those typically wired directly to the wire to the panel, or do people wire the Wall Connector to a NEMA 14-50 plug, and then plug it into a NEMA 14-50 outlet?

Those receptacles are rated for 50A, so I believe that means that I could not use a 100A breaker, and would need a 50A one. If so, is there a connector that is rated for 100A? I see some ones on Amazon that are 100A, but they are like $600 for plug and socket. Or I guess people just wire the Wall Connector directly to the wire to the panel?

So when people talk about NEMA 14-50 receptacles, does that mean they are not using a Tesla Wall Connector and just plug the car directly into the NEMA 14-50 because the cars have on-board chargers? And if so, is that slower charging than if they use the Tesla Wall Connector directly wired to a 100 Amp breaker?

And finally, do people ever use another brand of wall charger with Teslas? And if so, do any have faster charge rates without being much more expensive? I read there are some that have adapters and can charge many brands of cars.

Are you planning on Daisey Chaining for multiple EV's with their own respective Wall Chargers?

 

[Trebor Srevlis]

Have no plans for more than one EV, but the 2 gauge wire should allow that later.

 

[DCGOO]

Have no plans for more than one EV, but the 2 gauge wire should allow that later.

It would do that of course, but 2 gauge is really unnecessary. No new Tesla will ever charge at more than 48 amps, requiring a 60 amp circuit. Even if you get a second Tesla, wall connectors are designed to support load sharing automatically with a data cable between them. There is nothing wrong with installing 2 gauge if you really want to, but it is overkill and it’s capacity will never be used. If you are shopping, I would suggest getting a quote for 6 gauge, 60 amp circuit along with your 2 gauge 100 amp quote, and see if you still want to go there. 6 gauge Romex is available and does not require conduit in many cases.

I have an X with 72 amp capability, and a 3 with 48 amp capability. I charge both vehicles using a single 60 amp circuit, with the master wall connector set to 48 amps. It works perfectly and was vastly easier to install.

 

[Steinmetz]

You really should decide on your required Amperage capacity at the Wall Connector location.Knowing that, the distance involved , conduit or Romex, will determine the wire gauge required. NEC RECOMMENDATION is voltage drop of 5% or less combined feeder and branch circuits.

 

[animorph]

I have two wall connectors sharing a 100A circuit with 2 gauge copper wiring. That gets me 72A to my X if it is charging alone, 48A to the 3 if it is charging alone, or 40A to both if they are charging at the same time. It's as future-proof as you can get. While we planned to allow for two wall connectors, they were installed over a year apart. So one wall connector on a 100A circuit is not totally crazy. The only real difference is the extra wire cost.

 

[Rocky_H]

Yes, they are hardwired. If you are up for doing the 100A capable circuit wiring run, that would not be a bad idea to do for the future proofing because the long wiring run is the main part of the labor. But I would probably end that in a small subpanel or junction box, so you can easily make changes to it later from that point to add a second one. It will make that second job a bit cheaper/quicker.

 

[Trebor Srevlis]

"It would do that of course, but 2 gauge is really unnecessary. No new Tesla will ever charge at more than 48 amps, requiring a 60 amp circuit"

Why will no new Tesla charge over 48 amps? Not even a 2023 Cybertruck with a 300 kWh battery?

 

[DCGOO]

"It would do that of course, but 2 gauge is really unnecessary. No new Tesla will ever charge at more than 48 amps, requiring a 60 amp circuit"

Why will no new Tesla charge over 48 amps? Not even a 2023 Cybertruck with a 300 kWh battery?

Ok, I will grant you that. But no one knows what they will offer for the Cybertruck since it will be several years before that vehicle is available. A bigger pack gets you range, especially when towing, but does not necessarily mean you eat more for routine daily driving. Which is what home charging is designed to cover. Tesla seems to be backing away from using 90 or 100 amp circuits for anything at home. So I suppose I should have said "for any currently available models."

My X can charge at 72 amps, but you cannot buy that option any more. Frankly, 48 amps fills the daily needs of my X in a couple of hours. If I need a more aggressive schedule, I can go to a supercharger. But in 5 years of Tesla driving, that has only happened to me once.

 

[Rocky_H]

A bigger pack gets you range, especially when towing, but does not necessarily mean you eat more for routine daily driving. Which is what home charging is designed to cover. Tesla seems to be backing away from using 90 or 100 amp circuits for anything at home. So I suppose I should have said "for any currently available models."

I find this is a blind spot that a lot of Tesla owners have, and it needs a reminder from time to time.

AC charging is not just for at home. High amp AC charging is a very useful thing for filling gaps on routes between Superchargers or other fast DC charging stations. There are still routes on major U.S. federal highways that are hundreds of miles long in between Superchargers. These routes frequently have 75 to 80A wall connectors installed at businesses along the way to somewhat cover those gaps. These have been arranged by Tesla owners who needed them. But there are getting to be fewer and fewer cars that can make good use of them, and it is making these routes difficult to travel.

 

[Tim K]

Hi - distance (voltage drop) has major impact on size cable. I have a 95 foot run from the main panel and put in a 100 amp sub panel in teh garage for my 14-50 & HPWC. I can only use one at a time and have the HPWC set to 72a as my X has that option. Charges at 50+mph. This required 2/3 with ground MC. https://www.southwire.com/calculator-vdrop