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Home Charger only charging at 18amps

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Hi all,

I'm a personal assistant and my boss and their spouse each have Tesla's (2021 Model Y and 2021 Model 3) and had a home charger installed before I came on board. The home charger is only charging at 18amps. If you adjust the car to take a charge beyond 18 amps, it charges for 10 minutes and then turns off. It does this on both of the household's Teslas and even on a Tesla that belonged to a friend of theirs who came over to test it out.

I had the electrician who installed it come out and he said that he doesn't know why it wouldn't be able to charge beyond 18 amps- he says that that amperage wouldn't be straining the panel that supplies power.

I'm not familiar with teslas and this is in my lap now. Anyone have any ideas what the issue could be?
 
There's more to it than the panel.
- The charger must be configured to provide a maximum power that respects the panel/breaker/wire limits.
- The charger tells the car how much it can provide maximum
- The car decides how much to pull, up to that maximum
The fact you can go higher than 18A in the car means the maximum is higher. You probably see 18/32A or something like that. That second number is what the charger allows.
The fact that charging stops after 10 minutes, assuming you haven't reached your target charging limit, is because an error occurs. Normally, a message should be displayed on the car when that arrives. If you are too late and haven't seen the message, you can go in the message log of the car to see what that message was. I think it's under "service", a button called "Notifications".
Often, it's because something heats more than it should (there are thermal sensors in the charger, in the car etc..). Other times it's because the voltage drops below a certain acceptable threshold, which might indicate a wire that is too long / too thin for the power that's pulled from it.

Have a look at the error message and report back here.
 
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Hi all,

I'm a personal assistant and my boss and their spouse each have Tesla's (2021 Model Y and 2021 Model 3) and had a home charger installed before I came on board. The home charger is only charging at 18amps. If you adjust the car to take a charge beyond 18 amps, it charges for 10 minutes and then turns off. It does this on both of the household's Teslas and even on a Tesla that belonged to a friend of theirs who came over to test it out.

I had the electrician who installed it come out and he said that he doesn't know why it wouldn't be able to charge beyond 18 amps- he says that that amperage wouldn't be straining the panel that supplies power.

I'm not familiar with teslas and this is in my lap now. Anyone have any ideas what the issue could be?
Any messages on the car's screen when it turns off? Red T light near the plug at the car? Red lights on the charger?

I'm assuming that this is a Tesla Gen3 HPWC(glass front) permanently mounted on the wall, please feel free to correct me if I'm wrong. Many of them have trouble with overheating up until the -G revision, but there would be messages and red lights, and they tend to throttle down the current rather than cutting it off entirely.
 
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Any messages on the car's screen when it turns off? Red T light near the plug at the car? Red lights on the charger?

I'm assuming that this is a Tesla Gen3 HPWC(glass front) permanently mounted on the wall, please feel free to correct me if I'm wrong. Many of them have trouble with overheating up until the -G revision, but there would be messages and red lights, and they tend to throttle down the current rather than cutting it off entirely.
Thanks, I'll be checking for the error message today and the red lights. I'm attaching some photos of the charger, not sure if it';s the one you're referencing.
 

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Thanks, I'll be checking for the error message today and the red lights. I'm attaching some photos of the charger, not sure if it';s the one you're referencing.
So, yes, that's a Gen3 HPWC. You should look at the left side of the charger for the model number/revision. If its ending in -G, it isn't prone to overheating.

If you can get in the car, you can check the 'Driving...Service...Notifications' in the in-car screens to see notifications that may have been displayed but timed-out during the charging sessions. (that's the car icon on the lower left of the screen, a press on 'service', and then a press on 'notifications')
 
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So, yes, that's a Gen3 HPWC. You should look at the left side of the charger for the model number/revision. If its ending in -G, it isn't prone to overheating.

If you can get in the car, you can check the 'Driving...Service...Notifications' in the in-car screens to see notifications that may have been displayed but timed-out during the charging sessions. (that's the car icon on the lower left of the screen, a press on 'service', and then a press on 'notifications')
Many thanks to you, this is very helpful! I'll check that today.
 
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Many thanks to you, this is very helpful! I'll check that today.
Sorry I've been away, hopefully this isn't a dead thread. It looks like this charger is the kind that can overheat, since the model number doesn't end in -G.

I also discovered that the problem isn't occurring on the Model Y. When I set the amps to charge at 40A on the Y, it slowly reduces the amps over the course of an hour or so. So it doesn't turn off, but it still isn't taking a charge at the correct amps consistently.

Still waiting to get opportunity to get error code on Model 3 when it shuts off.
 

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Any messages on the car's screen when it turns off? Red T light near the plug at the car? Red lights on the charger?

I'm assuming that this is a Tesla Gen3 HPWC(glass front) permanently mounted on the wall, please feel free to correct me if I'm wrong. Many of them have trouble with overheating up until the -G revision, but there would be messages and red lights, and they tend to throttle down the current rather than cutting it off entirely.
On the model 3, the charger goes from green to red
 
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Sorry I've been away, hopefully this isn't a dead thread. It looks like this charger is the kind that can overheat, since the model number doesn't end in -G.

I also discovered that the problem isn't occurring on the Model Y. When I set the amps to charge at 40A on the Y, it slowly reduces the amps over the course of an hour or so. So it doesn't turn off, but it still isn't taking a charge at the correct amps consistently.

Still waiting to get opportunity to get error code on Model 3 when it shuts off.
Yes, open a case with Tesla and they'll send you a replacement charger. Happily the swap doesn't take an electrician, you can just remove four screws(two from above, two from below) from the charger, pop it off, and reinstall the new one.
 
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BTW, this is the latest info I've seen regarding requesting replacement...

 
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BTW, this is the latest info I've seen regarding requesting replacement...

thanks!
 
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