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Electrician coming - final verification

OK the electrician is coming today (YAY!!!) Still a month off from delivery but this is a great first step. I THINK I have it but want to confirm with everyone that this set-up will be ok:

I ordered the Bryant 9450FR NEMA 14-50 outlet for the garage:

Given that it's in the garage I am thinking I will need a GFI 50 Amp Breaker (I've seen all these confusing threads about 40Amps etc ...something to do with the car only pulling a certain amount and not close to 50 but I think I should stick with 50 right???)

I also ordered the 14-50 NEMA adaptor from Tesla.

This set-up should work fine correct?
 
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I can’t speak to the outlet (although any NEMA 14-50 outlet should work with Tesla's NEMA 14-50 adapter) but about the 50A breaker, the reason people talk about 40A is because that is the maximum rated current for any 50A breaker. Breakers are generally de-rated to provide 80% of the breaker amperage on a continuous basis.
 
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Sophias_dad

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Jul 29, 2018
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Massachusetts
You should get the 14-50 wired for 50 amp service, even though the UMC will only truly use 32 of that. It is admittedly confusing, but to get 32A continuously the circuit should be designed for at least 40 amps.

The reason to to 50 amp service is so that at some future point you can plug a different charger in and get 40 amps continuously out of it.
 
Thx! I have seen SO MANY conflicting articles re: GFCI. Some say not necessary and due to the onboard GFCI will cause faulty breakers, other say to use one. UGH! I think I am leaning towards not using one and swapping out later if necessary. Given the ambiguity out there AND the significant cost increase on the breaker itself, does not seem worth it to me.
 

Sophias_dad

Active Member
Supporting Member
Jul 29, 2018
2,585
3,023
Massachusetts
Thx! I have seen SO MANY conflicting articles re: GFCI. Some say not necessary and due to the onboard GFCI will cause faulty breakers, other say to use one. UGH! I think I am leaning towards not using one and swapping out later if necessary. Given the ambiguity out there AND the significant cost increase on the breaker itself, does not seem worth it to me.
It may not be up to you. I assume the electrician won't install a new garage outlet that doesn't have a GFCI breaker, if one is required.
 

Rocky_H

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Feb 19, 2015
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Boise, ID
Thx! I have seen SO MANY conflicting articles re: GFCI. Some say not necessary and due to the onboard GFCI will cause faulty breakers, other say to use one. UGH! I think I am leaning towards not using one and swapping out later if necessary. Given the ambiguity out there AND the significant cost increase on the breaker itself, does not seem worth it to me.
Well, there are two questions, and it depends on what you're asking:
1. Does it make sense? No, it's kind of hokey and pointless and does have potential to cause unnecessary problems.
2. Does code require it? Yes.

So I don't really consider it a question up for debate. I am not going to put in a code violation or recommend anyone to.

And yes, I and most here recommend just doing it as a full normal 50A circuit if you can--breaker, wire and 14-50 receptacle all set for that level. There is a possible exception that can allow 50A outlet types on 40A circuits, but it's generally just nicer to have it as a full standard level one that matches the outlet type.
 
Not the most exciting thing I'm sure but OUTLET IN! Cannot wait. Opted for no GFCI based on some of the annoying stories I am hearing.

outlet.png
 
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OK the electrician is coming today (YAY!!!) Still a month off from delivery but this is a great first step. I THINK I have it but want to confirm with everyone that this set-up will be ok:

I ordered the Bryant 9450FR NEMA 14-50 outlet for the garage:

Given that it's in the garage I am thinking I will need a GFI 50 Amp Breaker (I've seen all these confusing threads about 40Amps etc ...something to do with the car only pulling a certain amount and not close to 50 but I think I should stick with 50 right???)

I also ordered the 14-50 NEMA adaptor from Tesla.

This set-up should work fine correct?
I am looking at this exact same set up as I expect my M3LR delivery in June 2022. How is the Bryant working for you? I will be having the GFCI 50A breakers installed as well. Did your electrician happen to provide information on what industrial grade copper wire they used? Tx!
 
(I've seen all these confusing threads about 40Amps etc ...something to do with the car only pulling a certain amount and not close to 50 but I think I should stick with 50 right???)
Perhaps the confusion about 40A is the following:
  • A circuit can be used up to 80% of its maximum for continuous loads like EV charging. So a 50A circuit can be used for EV charging up to 40A.
  • A 14-50 or other x-50 outlet can be on a 40A as well as a 50A circuit, since there are no x-40 outlets. If that is the case, the circuit can support up to 32A continuous loads like EV charging.
For a new 14-50 outlet installation, it is best to install a 50A circuit, unless the difference between 40A and 50A circuits would be too much for your main panel. Note that the Tesla mobile connector with 14-50 plug adapter will only do 32A, so it can be used on either a 40A or 50A circuit, but there are also 40A plug-in EVSEs available that would require a 50A circuit. If you think in the future you may want to install a 48A (hardware) EVSE in place of the outlet, you may want to have 60A-capable wiring run.
 
There are legitmate reasons why you might opt for a 40a circuit (or even smaller), for instance, not enough capacity left in your service or panel, smaller wiring already in place, etc... Essentially any situation where going bigger is going to trigger significant extra costs. However, if you can, you should do the 50a circuit. I also recommend using wiring capable of 60a just in case you wish to upgrade to a wall connector at some later date.

I've got one 6-50 wired for 40a because i didn't know any better back in 2011 when I was having the work done for my new LEAF (since the LEAF maxed out at 16a, anyway, 30a charging seemed future-proof). The install guide for my EVSE said 40a on a 6-50, so that's what I did. Still works fine and I charge my M3 every night using the 30a EVSE that I got back then (Every year or so, I open it up and check for any signs of loose connections or heating). When I added the M3 and became a two EV household, I did a second 14-50 outlet with a 50a breaker, but wire capable of supporting 60a. The electrician had already assumed I would want it that way, and I didn't even have to ask.
 
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I am looking at this exact same set up as I expect my M3LR delivery in June 2022. How is the Bryant working for you? I will be having the GFCI 50A breakers installed as well. Did your electrician happen to provide information on what industrial grade copper wire they used? Tx!

Working well. No info specifically but I will say the cost of the wire was insane. I can't recall exactly now but I think it was close to $200 for a 40 foot run.
 

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