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20 or 30 amp breaker for tesla wall charger

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Agreeing with the previous posters:
  1. Ya got 50A wire. You use a 50A breaker. Ditch the 60A breaker. It's not safe, it's the wrong one, period. Get the GFCI type of 50A breaker, as previous posters have noted.
  2. Ya got 50A breaker, 50A wire.. but that nutty NEMA14-50 is labeled, "30A". This raises weird flags. It might be a real 50A NEMA14-50, but somebody's playing silly buggers with labels. Get the actual part number (may be on the front) and manufacturer and see what ya got. If it is some bizarre 30A version of a NEMA14-50 socket, throw it out and far away and put in a real NEMA14-50.
  3. If it turns out to be a real NEMA14-50, check the manufacturer and report back here. I don't use this kind of socket, but there's been multiple posts that the cheaper versions of this kind of socket don't last, especially if you're plugging in/plugging out on a regular basis. If that's the case, find out what the high-quality type is, get one, and use that.
Once all this is settled, your UMC will get you 32A, that being all it's good for. If you want more current, you can get 40A with your NEMA14-50 by using a TWC with a NEMA14-50 plug on it. Or wiring it directly to that wire. That's your call and how much money you want to spend.

Sorry about the doom and gloom.. but I was right about the 60A breaker :).
1) Will do, I'll go grab one this weekend.
2) It's labeled Tesla and all, even the eBay ad is the same way, hence my confusion. I'll double check and Google the part number on it just to see what comes up but that 30A threw me off.
3) Noted. My charger stays plugged in all the time, I've only ever taken it out to relocate the outlet itself since I didn't have enough slack initially to reach the car, hasn't been out since.

Meh, it chargers overnight and gets the job done...I'm not inclined to buy a $400+ TWC unless I come across some stupid deal.

You're good, I know what you meant :)
 
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Related question, because I can see there are many smart people on this thread. Exactly why is GFCI required? I can understand why these are needed for kitchen and bathroom outlets, but why an indoor EV charger? I ask because the electrician I hired earlier this year put in a non-GFCI breaker, and I’m trying to sort out whether I need to get that fixed. And he put in a Leviton 14-50 outlet which I know I should probably upgrade. I never unplug my UMC so I’m not worried about wear and tear, but it is in the back of my mind.
What's the issue with Leviton anyways? I don't unplug my UMC either other than maybe twice to relocate the outlet and another time to see the 30A stamp which bought me to this post.
 
Pretty sure the GFCI requirements has always been there and applies to potentially wet areas (kitchen), outlets on the side of a house and the garage. I believe the “EV” notation was more of a clarification to make it clear it is still needed. Bottom line, it is required by code.

And @m5james: be sure to look at the outlet brand, if it is a Leviton, replace it!
What's the deal with Leviton anyways? That's been mentioned more than once without any reasoning.
 
Pretty sure the GFCI requirements has always been there and applies to potentially wet areas (kitchen), outlets on the side of a house and the garage. I believe the “EV” notation was more of a clarification to make it clear it is still needed. Bottom line, it is required by code.

And @m5james: be sure to look at the outlet brand, if it is a Leviton, replace it!

No, it wasn’t always there. They didn’t even require gfcis till the late 80s, and only in the early 2000s did they require it for everywhere in the kitchen. The GFCI requirement for the outlet in the garage is specifically for EVs, not (for example) welders.
 
This has been one of the more interesting threads on this topic, and I have read quite a few of these.

@Tronguy , to summarize one small part, it appears to me that the "14-50 thats marked 30 amp" thing, was in reference to the tesla adapter (and since been explained) vs what it sounded like it was previously, which was a 14-50 OUTLET with "30 amp" written on it.

Looks like the rest of that has been sorted out, and it was an interesting read.
 
Nope. The maximum ampacity of #8 Romex is 40 amps, which would require a 50 amp breaker.
What you’re saying makes no sense.

Yes, #8 NM-B has a max ampacity of 40 amps, meaning it can be used in a 40 amp circuit. That 40 amp circuit, if used for an EVSE, would be able to provide 32 amps max on that 40 amp circuit, due to the continuous load rule.
 
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What you’re saying makes no sense.

Yes, #8 NM-B has a max ampacity of 40 amps, meaning it can be used in a 40 amp circuit. That 40 amp circuit, if used for an EVSE, would be able to provide 32 amps max on that 40 amp circuit, due to the continuous load rule.

You can draw 40 amps from 8 Romex.

You can only draw 40 amps from a circuit protected from a 50 amp breaker. The overcurrent protection device needs to be sized 125% the continuous load. 40*125% = 50 amps. The current draw on the wire is still 40 amps. The over current protection device is a 50 amp breaker.

You are trying to combine two separate things.
 
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You can draw 40 amps from 8 Romex.

You can only draw 40 amps from a circuit protected from a 50 amp breaker. The overcurrent protection device needs to be sized 125% the continuous load. 40*125% = 50 amps. The current draw on the wire is still 40 amps. The over current protection device is a 50 amp breaker.

You are trying to combine two separate things.
#8 Romex is only good for a 40a circuit, meaning no bigger than a 40a breaker. Therefore, for EV charging, you can only draw 32a.
 
The maximum amperage rating of the circuit, circuit breaker can't exceed the maximum amperage rating of the wire used in the circuit.

The maximum amperage rating of the wire used in a circuit can exceed the maxim amperage rating of the circuit breaker. This enables you to later upgrade the circuit, circuit breaker and receptacle if desired up to the maximum supported by the wiring provided there is sufficient capacity in the home.

Since there is no specific 240V receptacle rated for 40 amps you can use a receptacle such as the 14-50R that is rated for 50 amps with a 40 amp circuit, circuit breaker. The wire must be rated for at least 40 amps. In this example the circuit breaker used cannot exceed 40 amps, i.e. be changed to a 50 amp circuit breaker without also replacing the circuit wiring after determining that there is sufficient capacity for the 50 amp circuit instead of a 40 amp circuit. If there is sufficient capacity for a 50 amp circuit then it would make sense to install a 50 amp breaker, 50 amp rated wiring and the 240V/50A receptacle instead of configuring the circuit for 40 amp.

The 80% rule is specific to plug-in and electric vehicle charging and other continuous load applications such as pool circulating pump motors.
 
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What's the deal with Leviton anyways? That's been mentioned more than once without any reasoning.
The forums are full of posts of the Leviton charring wires or cracking over time, or worse. The Leviton is deigned to be used occasionally, such as with a welder, it is not designed for continuous use. The UMC will pull 32A for many hours continuously. Search the forums and make you own decision.
 
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No, it wasn’t always there. They didn’t even require gfcis till the late 80s, and only in the early 2000s did they require it for everywhere in the kitchen. The GFCI requirement for the outlet in the garage is specifically for EVs, not (for example) welders.
Nope:

"The National Electricity Code says that GFCI-protected outlets are required for garages. Your local building codes will also state that outlets must be GFCI. This change to the code took effect back in 2008 for all 125-volt, single-phase, 15- and 20-amp outlets. GFCI’s are also required according to the International Residential Code, or IRC.

"The code also states that GFCI is necessary for the outlets for garages that are at or below ground level. The reason is there’s a high risk of flooding or other water damage with a lower floor, and the outlets must be able to shut off quickly."
 
Nope:

"The National Electricity Code says that GFCI-protected outlets are required for garages. Your local building codes will also state that outlets must be GFCI. This change to the code took effect back in 2008 for all 125-volt, single-phase, 15- and 20-amp outlets. GFCI’s are also required according to the International Residential Code, or IRC.

"The code also states that GFCI is necessary for the outlets for garages that are at or below ground level. The reason is there’s a high risk of flooding or other water damage with a lower floor, and the outlets must be able to shut off quickly."

Not sure what you are noping at…