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Anyone ever use a 240 volt dryer outlet to charge when visiting relative or friend? do set max amp rate in car to safe amount.

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Anyone ever use a 240 volt dryer outlet to charge when visiting relative or friend? I assume you must be careful to limit your charge rate to 20 amps.
It seems one can make it to your relative's destination but not have enough charge to get to a supercharger on the return trip home.
 
Um... it depends on where you start(home) and where you finish(relatives house)

In theory, you shouldn't need to limit the charge rate. Most dryer outlets are 14-30, which means if you are using the right adapter(direct from the UMC) it'll limit the car to 24 amp charging.

The only place this gets a bit sticky is when you use the 14-50 adapter(assuming you have a 14-50 receptacle), and the car won't know if its on a 50 amp circuit or a 40 amp circuit, and even then it doesn't matter because your UMC has a hard-limit of 32 amp charging.

If you are using a 14-30 to 14-50 adapter and then plugging the umc into the 14-50, it'll try to get 32 amps out of the 30 amp circuit and after a while the breaker will trip. You should manually turn the charge rate to 24 amps in this case.
 
When I drove my Bolt to my sisters place and needed to charge over night, she said, "no problem, we have a 240V outlet in the garage from when we had an electric water heater"... when I got there and looked at the outlet, it looked melted.... so I made sure the breaker was turned off, made sure it was dead with a multi meter and disassembled it. The wire ends at the breaker looked like they were in perfect condition, and the wire ends at the outlet were fine, but the outlet itself looked like it had an internal fault that caused the damage. I replaced it with a new outlet, and used my "home built" 240V extension cord coupled with an adjustable amperage L2 EVSE set to 24 amps and everything worked out fine. If I didn't know how to do wiring I would have been SOL though!

Keith

PS: I always recommend a stout 240V extension cord (mine is a welding extension with different plug and socket attached) when charging at a relatives house off of their dryer plug... it is seldom in a convenient location for plugging in the car.
 
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Plugged in many times to family and friends 240 dryer outlet. Usually no problem. I have a 50 amp fuse at home, usually charge 30 amps or so. Plugging into my father-in-laws and the car dial did not down the amperage and popped the breaker. No big deal, but embarrassing, especially at night trying to locate the breaker box. I usually reduce amperage to 20A to be safe, and check the wiring for any excessive heat. I carry a thick, 50 amp extension cord.
 
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If you use the Tesla connector ( purchased from Tesla current price $ 35 plus tax) ) then it will automatically set the current to 24A, or else you may need to check and set it manually to 24A if it does not set itself to 24A.
 
When I drove my Bolt to my sisters place and needed to charge over night, she said, "no problem, we have a 240V outlet in the garage from when we had an electric water heater"... when I got there and looked at the outlet, it looked melted.... so I made sure the breaker was turned off, made sure it was dead with a multi meter and disassembled it. The wire ends at the breaker looked like they were in perfect condition, and the wire ends at the outlet were fine, but the outlet itself looked like it had an internal fault that caused the damage. I replaced it with a new outlet, and used my "home built" 240V extension cord coupled with an adjustable amperage L2 EVSE set to 24 amps and everything worked out fine. If I didn't know how to do wiring I would have been SOL though!

Keith

PS: I always recommend a stout 240V extension cord (mine is a welding extension with different plug and socket attached) when charging at a relatives house off of their dryer plug... it is seldom in a convenient location for plugging in the car.
How long of an extension cord do you recommend?