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Can I install a NEMA 14-50 now and convert it to a Tesla wall charger later?

Can I install a NEMA 14-50 now and convert it to a Tesla wall charger later?

What do I need to tell the electrician so that I can use the wire being installed Tuesday for NEMA 14-50 to supply power to Tesla wall charger someday? Can it be done? Would the box connection have to be redone? What type of wiring can handle both?

Thanks to all those with electrical knowledge in advance.

Xerogas | July 8, 2018

Buy one of these, plug it into your NEMA 14-50, and just leave it on the wall? https://shop.tesla.com/us/en/product/vehicle-accessories/model-s_x_3-gen...

Depends on what your reason for wanting the larger wall charger is. For most people, the mobile connector is plenty

stevenmaifert | July 8, 2018

The answer is yes, but the HPWC will require a 60A breaker for 48A charging to your Model 3 and probably a heavier gauge wiring from your breaker box than would be required for the NEMA 14-50. If you are serious about a future upgrade, best to do the wiring and breaker now.

Steven.haver | July 8, 2018

It depends on what your goals are—why do you want the Wall Connector? And why don’t you want it right now? If you want to someday install multiple Wall Connectors to charge multiple vehicles simultaneously, then that’s one set of considerations. If you just want to get your full 48A (11.5kW) charge rate for a long range model 3, then that’s another set of considerations.

14-50R can accept up to 4AWG but it’s pretty hard to work
with (thick cable, hard to maneuver). Easier to use 6AWG, which is what a lot of people here on the forums have done, but that will decrease the max amperage. It also depends on your build envinronment. Does the cable go through an attic? Through wet environments? The rating for 6AWG is
55A (60 °C), 65A (75 °C) 75A (90 °C)

What would be really helpful is a service loop (extra wire length) somehow included in the box or conduit. If you don’t have enough cable length to install the Wall Connector, then you will either have to re-run wire or make that electric box a junction box.

Some advice for your 14-50 install:
1) Make sure it’s high enough off the ground (for ease of use, so no one trips on it, and to avoid inadvertent water exposure). Remember that your UMC will hang down a couple of feet.
2) The ground pin should be facing up.

SUN 2 DRV | July 8, 2018

@ Garyeop The Wall Connector and a 14-50 outlet can use similar wiring. But ideally the Wall Connector would like to be on a 60 amp two wire circuit and the 14-50 on a three wire 50 amp circuit. Why pay for more and thicker wires than either one needs by itself?

To charge at the car's max 48 amp rate you'll need a Wall Connector on a 60 amp circuit. Is it feasible to just install a Wall Connector from the outset, rather than having to figure out what to install to support both?

Garyeop | July 8, 2018

Answer to most questions...I am cheap. I want to see if I can get by using my included cord and a NEMA 14-50. If not, I want to spend as little as possible to upgrade. I think the best answer is to buy a second set of charge cables if I get tired of pulling mine out of the car every night. The charge rate is plenty with the NEMA plug.

Thanks for the advice!

Atoms | July 8, 2018

If you wish to upgrade someday, tell them that and install Awg6 or Awg4 wires (black and red) and Awg10 for ground. This will handle 60A line required for 48A charging. Just check to see how you would install the wall charger and make sure the 14/50 box is installed such that it is an easy swap. Th circuit breaker would need to be changed from 50A to 60A and the electrical box replaced with the wall charger.

chuck | July 8, 2018

You certainly can and it's a good strategy.

A Tesla HPWC will install over and cover a flush-mounted single-gang wall box. A 14-50 will install in a -- preferably deep -- single-gang wail box.

Most any electrician will install a NEMA 14-50 with AWG8 (a.k.a Eight Gauge, or #8 wire) wire. Code allows up to 55A through #8 and a 14-50 is only rated for 50A, so it's a good fit. But, a Tesla HPWC can use up to 80A. The Model 3 is limited to 48 actual charging amps. But, who knows? Maybe there's an X or S or maybe a future Tesla model in your future. Besides, to charge a Model 3 at 48A requires a 60A circuit to the HPWC.

So my suggestion to people installing a 14-50 for Tesla charging is to do three things a little bit differently:

First, use -- or have your electrician use -- #6 or #4 wire (paradoxically, wire gets bigger as its AWG number gets smaller). The heavier wire will cost a bit more (maybe a dollar or two per-foot more, copper is expensive) and an electrician may charge you a little more for labor to install the heavier wire just because it's more difficult to work with. BUT, once the heavier wire is in, you'll be able to upgrade the circuit in the future if you decide to install a hard-wired HPWC. Otherwise, to fully utilize an HPWC, you'll have to replace the wire and the putting in of the wire is often the major expense in installing such a circuit.

Second, leave -- or ask your electrician to leave -- an extra foot or so of "slack" wire in the wall cavity behind your new 14-50 outlet. You -- or your electrician -- will be thankful for this bit of extra wire if and when you decide to convert the outlet to a hardwired HPWC.

And, third, an HPWD should be installed about 48-58 inches above the floor. So install -- or ask your electrician to install -- the NEMA 14-50 at about that height. If, in the future, you upgrade to a hardwired HPWC, it can be mounted right over the wall box that the 14-50 was removed from.

If you thusly install a NEMA 14-50 outlet, then, if you decide to upgrade to a hardwired HPWC in the future, all you -- or your electrician -- need do is remove the 14-50 cover plate and outlet, pull out the handy extra length of wire, cap the neutral wire since the HPWC doesn't use it, install the HPWC over the wall box, and upgrade the circuit breaker in the breaker panel.

If you later decide to remove the HPWC -- perhaps you decide to sell your house -- all you -- or your electrician -- need to is remove the HPWC, spackle and paint the holes from its the mounting screws, uncap the neutral wire, reconnect the 14-50 outlet, push the extra wire back into the wall, mount the 14-50 and its cover plate, and put back the 50A breaker.

The point is: use heavier wire than is strictly necessary for a 14-50, leave a bit of slack, and mount the 14-50 about where you'd like to someday mount an HPWC.

chuck | July 8, 2018

By the way, if you want to use heavier wire on Tuesday, call your electrician first thing tomorrow morning to be sure that he brings the heavier wire with him. It's heavy stuff and he may not normally carry it on his truck.

SUN 2 DRV | July 8, 2018

@Garyeop In that case just get a regular 14-50 installed, and I'm sure you'll be more than happy with charging overnight.

Even when you go on a trip you'll most likely only use SuperChargers, which have their own cable. You don't need to bring your Mobile Connector.

The second most likely charging would be at one of the third party J-1772 stations. You'll need your J-1772 adapter, but again you don't need your Mobile Connector.

So you can virtually always leave your Mobile Connector at home.

I'm a big fan of the Wall Connector, but many people certainly get by with just using their Mobile Connector.

nagesh | July 8, 2018

Can some one post the pic of your 14-50 socket? How is ground pin up? is that in code?

chuck | July 8, 2018

"Even when you go on a trip you'll most likely only use SuperChargers, which have their own cable. You don't need to bring your Mobile Connector."

I would suggest at least bringing the J1772 adapter along.

Coastal Cruiser. | July 8, 2018

nagesh, that's an ez one. You can just google "NEMA 14-50r". The "r" stands for receptacle. Below is a link to a LEVITON brand, which I have found is decent quality. (Be advised though that if one is going to be constantly plugging and unplugging the cord, a far more expensive 14-50 outlet is required).

https://www.amazon.com/Leviton-279-Receptacle-Industrial-Grounding/dp/B0...

-------------
chuck, +1 for your posts on this topic.

rje2417 | March 26, 2020

Hello,
I’m currently using a nema 14-50 plug for charging my Tesla. It’s using 6 gauge wire and a 50 amp breaker. Can I use a Gen 3 charger with a 50 amp breaker and 6 gauge wire? It would be a big job to run new wire and don’t mind having slower charge time. Any help would be greatly appreciated!!!!
Thanks,
Rob

Big_Ed | March 26, 2020

Yes. Just set the HPWC accordingly during the commissioning process. 50A circuit gives you max 40A supplied to the vehicle.

https://www.tesla.com/sites/default/files/support/charging/Gen3_WallConn...

Earl and Nagin ... | March 27, 2020

@rje,
Big_Ed is correct.

Frank99 | March 27, 2020

Also, depending on the installation techiques, wire type used, and the associated hardware, you might be able to use a 60 Amp breaker which would give you a full 48A charge rate. I'd really recommend that you have a certified electrician make that determination, though, because there's a lot of caveats that need to be reviewed.

bjrosen | March 27, 2020

If you are ever planning on getting a Tesla Wall Connector then the most cost effective thing is to do it now. The biggest cost is having the electrician show up, one visit is cheaper than two. The TWC is only $500, my electrician charged me $750 to run a 240V/60A line and install mine. It's really convenient having a permanently wired in EVSE, a TWC is well worth the cost. If you really don't want to spend the money for a Tesla Wall Connector now then you should absolutely have the electrician run a 60A line, most of your expense is labor so there is no reason to cheap out on the wire.

Lonestar10_1999 | March 27, 2020

You could also run another set of #6 wires giving you 2- #6 per phase and connect it to a 100A-2P breaker. This would be the ideal circuit for the wall charger, especially if you plan on charging two Tesla vehicles simultaneously.