Electrical people. Opinions on this L2 Install?

[Supratachophobia]

Some codes allow to round up as a 55 amp breaker is rare.

Personally I’m not a fan of rounding up as at some point the person installing that circuit will not be around and all people will see is the 60 amp breaker and thing that circuit is good for 48 amp continuous load. I’d prefer the 50 amp breaker so the lowest portion of that circuit is visible and not hidden in a wall.

+1. Rounding up to the next available size breaker should be allowed (I think a snippet from the code was posted above), but my personal risk appetite is closer to SANZC02, and if charging at 40a anyway, a 60a breaker isn't going to make a difference in the first place. I'm happy for it to trip if it hits 50.

While I certainly respect everyone's individual risk tolerances, at the end of the day, the code, which is designed with the express purpose of your house not burning down, says that it's okay to charge at 48 amps on a 60 amp breaker.

6-3 on a 60 amp breaker is what Tesla originally had in their Gen1 and Gen2 hpwc install instructions and I've personally never had an issue nor heard of an issue with a hardwired charger running under those conditions. I will add that they called for pure copper explicitly. Certainly more issues with improperly installed 14-50 outlets and mobile charger. And by issues, I mean garages and houses burning down.

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[ElGuano]

While I certainly respect everyone's individual risk tolerances, at the end of the day, the code, which is designed with the express purpose of your house not burning down, says that it's okay to charge at 48 amps on a 60 amp breaker.

I thought we were talking about 40 amp charging here. With 48 amps, it's not just "ok to charge with a 60amp breaker," you MUST have it due to breakers typically being rated for non-continouous load (or 80% of their rating for continuous load).

 

[Supratachophobia]

I thought we were talking about 40 amp charging here. With 48 amps, it's not just "ok to charge with a 60amp breaker," you MUST have it due to breakers typically being rated for non-continouous load (or 80% of their rating for continuous load).

Oh. OP still totally needs #6 for 40amps continuous. Is he considering 8? That's a hard no.

 

[DucRider]

6-3 on a 60 amp breaker is what Tesla originally had in their Gen1 and Gen2 hpwc install instructions and I've personally never had an issue nor heard of an issue with a hardwired charger running under those conditions.

Gen 1 installation manual:
NOTE: For most branch circuits of 100A, use 3 AWG (26.7 mm2), 75°C (167°F) copper wire. For installations less than 100A, use conductors that are sized according to local electrical codes
Gen 2:
Use conductors that are sized in accordance with local wiring regulations. The selected cable must be able to sustain periods of constant load of up to the maximum amperage selected by the electrician.

 

[Rivian Owner]

If you are going to spend the money to put a sub panel in the garage, why not size the panel large enough for future expansion? The wire, panel, and breakers may cost a little more but the labor costs won't change. If you have to put holes in walls or the ceiling that will need to be patched, it makes sense to spend a little more to get some added capacity. Considering that you may eventually upgrade to bi-directional (BiDi) charging the upgraded capacity will save having to replace what your electrician is going to install now.

 

[SparkyR1t]

If you are putting in a sub panel, you might as well run something much bigger than 6

Agree if you’re doing a sub panel I would not go less than 100 amps for future growth. Also neutral and ground would be required but almost all wall connectors require a neutral or ground reference for circuitry and led lighting do it correctly and pull the extra conductor.

 

[babock]

Agree if you’re doing a sub panel I would not go less than 100 amps for future growth. Also neutral and ground would be required but almost all wall connectors require a neutral or ground reference for circuitry and led lighting do it correctly and pull the extra conductor.

Not all. None of my EV chargers(4 of them including 3 that plug into outlets) require neutral including the 240V input for the portable charger that comes with the Rivian.

 

[teartags]

Wow, this got out of hand quick. Didn't know I'd get 3 pages of responses!
Nowhere in my original post did I mention a subpanel.
I am running 6-3 Romex to a shutoff in the garage
6AWG THHN in conduit from shutoff to Charger
It'll all be hooked to a 50 amp breaker
I will charge at 40 amps.
Thanks again all.

 

[Electrified Outdoors]

technically you need #4 if your running NMB Romex for the 60 amp circuit even though your only charging at 48 amps. THHN in conduit is the way to go for max safety if you want #6. Another option might be #6 MC but not sure if it meets code. Make sure you pull a permit and get it inspected to CYA.

 

[babock]

technically you need #4 if your running NMB Romex for the 60 amp circuit even though your only charging at 48 amps.

My electrician just ran 6 AWG NMB romex. I was there when the city of Los Angeles building inspector signed off on it.

48A EV charger with 60 A breaker.

 

[godfodder0901]

My electrician just ran 6 AWG NMB romex. I was there when the city of Los Angeles building inspector signed off on it.

48A EV charger with 60 A breaker.

Sounds about right for LA...

 

[babock]

Sounds about right for LA...

You mean in that they actually follow code?

 

[godfodder0901]

You mean in that they actually follow code?

Yeah, let's go with that...

 

[Zoidz]

My electrician just ran 6 AWG NMB romex. I was there when the city of Los Angeles building inspector signed off on it.

48A EV charger with 60 A breaker.

Speaking from experience, you might (or might not) be surprised at how many inspectors don't know the NEC and will sign off without looking at the details. Other inspectors go the other direction - fail everything when they are in doubt, and make you prove otherwise.

The circuit needs to be 60A. The weakest link, #6 Romex, is not 60A.

 

[Electrified Outdoors]

My electrician just ran 6 AWG NMB romex. I was there when the city of Los Angeles building inspector signed off on it.

48A EV charger with 60 A breaker.

It will probably be fine, and you have it permitted. Can’t tell you how many times I have seen this. They love running that 6/2 ROMEX. The funny thing is the Romex is rated for 90c just like the THHN but NEC requires ampacity derating to 60C which is why its ampacity is only 55 amps.

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