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

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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!
 
Either the wall connector or a NEMA 14-50 will work well for Tesla charging.
In the future if you wanted to remove a wall connector and install a NEMA 14-50 that would not be difficult or costly to do as long as your electrician runs all 4 wires (2 hots, a neutral, and a ground) required for a NEMA 14-50. The Tesla wall connector only requires 3 wires (2 hots and a ground).

I installed my wall connector myself. It is not particularly difficult to do and there are many Youtube videos out there on the installation. I ran all 4 wires because I wanted the option to install a NEMA 14-50 if I ever have a need to do so.
Or, if you only have 3 wires (hot-hot-ground) you can install a NEMA 6-50.
 
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Why do you believe a 100 amp circuit would be required? The Tesla Gen3 Wall Connector is configured via a BT connection and your phone, tablet or laptop computer. The Gen3 Tesla Wall Connector can be configured for use on either 120V or 240V circuit rated between 15 amps and 60 amps. The Tesla Gen3 Wall Connector can support automatic load balancing where 2 or more Wall Connectors are charging at the same time.
My Gen 3 Tesla Wall Connector can only be used on 208/240 volt circuits rated 15, 20, 30, 40, 50, or 60 amps. No provision for running it from 120 volts.

Screen Shot 2022-12-07 at 10.43.13 PM.png
 
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Thank you so much for all the replies. I'm having second thoughts about my first electrician choice (they did a great job on my solar but they seem less knowledgeable about EV chargers). I'm leaning now towards just getting a 14-50 installed - I think that's the most future proof way to go. I think at some point all the charger ports on EV's will be standardized (although who knows - Apple still uses lightning cable so maybe Tesla is a big enough gorilla to have a proprietary standard and everyone else will have to add adapters).

Thank you so much! You've cleared up some of my misunderstandings. I'm looking forward to ordering my Model Y soon.
If you want to install two or more circuits for EV charging using a sub panel, the feeder to the sub panel needs to be designed for continuous loads. For example, if you install a Tesla Wall Connector using a 60 amp breaker and a NEMA 14-50 (or 6-50) on a 50 amp circuit, which will charge one car at 48 amps and another at 40 amps, the load calculation for the feeder needs to consider the load as a continuous load of 88 amps.

If you install the Wall Connector on a 50 amp breaker and the NEMA receptacle also on a 50 amp breaker, the cars will both charge at a maximum of 40 amps each and the load calculation for the feeder news to consider the load as a continuous load of 80 amps.

Note that such a circuit needs to be installed in conduit using THHN/THWN wire. The sub panel *could* be wired without a neutral since both loads would be strictly 240 volt loads, however I would install a neutral as it might be convenient to install some 120 volt circuits to the sub panel for other devices. And depending on your local inspector, he or she may require a neutral. In the event any additional circuits were installed in the sub panel, it would need to be fed with a larger breaker and larger wire to serve those additional circuits.

Personally I have two Tesla Wall Connectors for my Model X Plaid and Model Y LR with individual runs of #6 AWG THHN/THWN wire (in PVC conduit) run to my electrical panels. After spending over $200,000 for the cars, it did not make any sense to do it any other way, and was relatively easy as the panels are in the garage.

However, my son, who is on more of a budget that I am, shares a single Wall Connector on a 50 amp circuit for his Model 3 rear wheel drive and Model 3 Performance. Just requires a little coordination between him and his girl friend.

Using a sub panel and installing more than one circuit off the sub panel, installing two circuits back to your main panel or panels without a sub panel, installing a single 240 volt circuit with 20, 30, or 50 amp receptacles, or installing one or more Wall Connectors to the afore mentioned circuits depends on your particular circumstances and budget. I know of a person who only has 100 amp service in his house and he installed a 30 amp circuit (using #10 Romex (non metallic cable)) to a Tesla Wall Connector (charges at 24 amps) and has no problems. Car is always charged in the morning since he gets home about 6 PM. I think most people overestimate their requirements, but some have unique requirements were they need to charge faster than 24 amps. Only you know what you need.

I suggest using a licensed electrician for such electrical work, and getting a permit if required.

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What? No. You just need to use wire type and gauge that is appropriately rated for the level of circuit it is going to supply. What type is used is more determined by the location where the line is going to be run.
I was discussing two specific circuits that are feeders to a sub panel. The circuits for the capacity of the feeders I was discussing, with the wire size shown in the Mike Holt Electrical Toolbox need to be 75˚ rated wire, which is most often THHN/THWN wire run in conduit.
 
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I was discussing two specific circuits that are feeders to a sub panel. The circuits for the capacity of the feeders I was discussing, with the wire size shown in the Mike Holt Electrical Toolbox need to be 75˚ rated wire, which is most often THHN/THWN wire run in conduit.

My cursory view of the Mike Hold exercise was that one example was in a hot environment so THHN was used for derating. If adjustments or corrections to ampacity are not in play damp/wet is not a facctor, then any wire from the 75C column is a good choice
 
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My cursory view of the Mike Hold exercise was that one example was in a hot environment so THHN was used for derating. If adjustments or corrections to ampacity are not in play damp/wet is not a facctor, then any wire from the 75C column is a good choice
Neither Mike Holt example specified hot environment, and there is no derating for any reason in either example.

I concede the point that any 75˚ wire, not just THHN/THWN wire, can be used as long as it is suitable for the environment in which it is installed.

I just mentioned THHN/THWN wire because it is the most common wire available, and is what is most often installed. And I did not want someone think they could wire a sub-panel with an 80 continuous load with #3 AWG NM cable, or 88 amps with #2 AWG NM cable, which must be chosen from the 60˚ column in the ampacity tables. Since the largest copper NM cable made, to my knowledge, is #2 AWG, which is only good for 95 amps, there is no NM cable available that would be suitable to wire the sub panels in my examples.

Appropriately sized SER cable could be used, however that is almost always available in aluminum, and it would be really large size conductors and difficult to handle.

Therefore, the sub panels in my examples would most likely be wired with 75˚ wire, which must be installed in conduit or MC cable could be used in place of conduit. THHN/THWN is the most common such wire.

I hope this helps the OP understand what is needed when he is dealing with his electrician.
 
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Most future proof is to run a cable that can handle 100A (80A continuous)
But if on a sub panel, what size cable should that be? Do you want some other miscellaneous circuits on the sub panel?

I found a really nice calculator that does a lot more than the Mike Holt Electrical Toolbox:


It allows calculation using any kind of wire, and calculates for combinations of continuous and non-continuous loads.

Here are a few examples:

Sub panel with TWC set for 48 amps and 20 amps of miscellaneous (non-continuous) loads:

Screen Shot 2022-12-10 at 1.50.14 PM.png


Sub panel set for two 40 amp EV charging circuits, and 20 amps of other loads:
Screen Shot 2022-12-10 at 1.51.51 PM.png


Someone had a sub panel that was only fed with a 30 amp circuit (assuming NM-B cable): If other loads were only 5 amps, you could still charge at 20 amps without having to run new wire to the sub panel:
Screen Shot 2022-12-10 at 1.23.46 PM.png


Keep in mind this is 5 amps of other circuits at 240 volts, so you could divide 10 amps of 120 volt loads between each side of the 240 volt feeder circuit.

And if using more than one TWC cost can be kept down by using the power sharing capability of the TWC.

Hope this is helpful and interesting.
 
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I give up. Not worth the negativity.
I get your point but what @SageBrush was saying (perhaps in a negative way) is that there are actually a lot of factors and nuances in the electrical code; That’s why electricians actually go to school. Most of it isn’t necessarily hard, one just needs to know it and the risk of using a calculator is that in simplifying things it can miss important factors.
 
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