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At home 25kW DC charging

svet-am

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There is a bit more to it than that. The wire must be THN, THWN, SE... (i.e. rated 75 °C) and not NM-B or UF-B (60 °C) in order to use a 60A breaker with it and charge at 48A. The fact that your house has a 50 A breaker protecting this wire suggests it is not rated 75 °C. Unless you can verify that the wire is rated 75 °C you will have to stick with the 50A breaker and charge at 40A max.
The electrician who did the work for me verified that wiring would be fine. It was done at 50A previously by the previous homeowner (we see it in the permit history that he did it himself, another good reason to pull permits folks) and they slapped a 50A on for who knows what reason. It would be fine at 60A though.
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Zoidz

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There is a bit more to it than that. The wire must be THN, THWN, SE... (i.e. rated 75 °C) and not NM-B or UF-B (60 °C) in order to use a 60A breaker with it and charge at 48A. The fact that your house has a 50 A breaker protecting this wire suggests it is not rated 75 °C. Unless you can verify that the wire is rated 75 °C you will have to stick with the 50A breaker and charge at 40A max.
When this discussion comes up, I always ponder how many people will understand/know/care/etc. and how many house fires will result from DIY installs using NMB, or worse yet, aluminum wire to save money on wire costs.
 

wizard467

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When this discussion comes up, I always ponder how many people will understand/know/care/etc. and how many house fires will result from DIY installs using NMB, or worse yet, aluminum wire to save money on wire costs.
Running aluminum to a sub panel is fine as long as it is sized appropriately. Your main panel is probably fed by aluminum.
 

DB-EV

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No, no, no. Several EVSE are equipped with a NEMA 14-50P plug and are rated at 40A max charging rate. Such a unit MUST be plugged into a 14-50R receptacle wired to a 50 Amp. breaker using conductors rated for 50 Amps. Because of a weird exception in the NEC there are 14-50R receptacles wired to 40 Amp breakers. EVSE plugged into such an outlet must not charge at more than 32A and in order to be safe several manufacturers (Tesla and Rivian for example) limit the current their 14-50P equipped EVSE can deliver to 32 A.

If you have a 14-50R receptacle in your house you must insure that the breaker and wiring are rated at 50A before plugging in a 40A EVSE. If your 14-50R is on a 40A circuit you must not install EVSE capable of charging at 40A.
Sorry dude, that's what I meant, I think. I didn't go check my prior research. For some reason I thought it could go into a 48 A (which may not exist) and would provide 40 A draw.

Don't hit me : )
 

flabyboy

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Imagine what would happen if all homes in the neighborhood had something like this installed. I hope we are prepared for what is coming the next decade. I doubt we are
 

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Zoidz

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Running aluminum to a sub panel is fine as long as it is sized appropriately. Your main panel is probably fed by aluminum.
As an electrical engineer, I'm completely familiar with the NEC and aluminum wiring installation requirements. It's alot more than sizing it properly. As I stated in my original comment, I'm referring to DIYers that don't know and/or don't care, resulting in expansion/contraction issues, oxidation of connections, and possibly ending in a fire.
 

Pherdnut

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Seems like a lot of $ for just a few more miles an hour. Doesn't everybody have to sleep eventually?
 

ajdelange

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Seems like a lot of $ for just a few more miles an hour. Doesn't everybody have to sleep eventually?
Most of the time a slow charging rate is more than sufficient. When you need the juice is for the situation where you need to leave the house with 85 or 90% SoC rather than at the 60 - 70% to which you normally charge. IOW you want to add 10 - 30% in a few hours. Then you want the max 10.52 kW charging so you can top up in a couple of hours.
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