Can I install a 60 amp circuit breaker for the wall charger if I have a SR version?

[johnruiz94]

I have a Model 3 SR, and Tesla says the Rear-Wheel Driver version can charge at 32A and recommends to install a 40 amp breaker.

Can I still install a 60 amp breaker and it wont damage the car in any way? I want to future proof the circuit breaker in case I get a new car later or ever upgrade cars. I just want to make sure electrically I'm not ruining anything.

 

[Rice&Curry]

If you use a Tesla home charger, then it will automatically adjust itself to the current ( 60 amp will deliver 48 amps) . I have installed a 60 amp circuit breaker in my house.

 

[Sophias_dad]

The charger won't deliver more than the car can take, so going with the 60 amp breaker is the right move.

 

[johnruiz94]

Thanks guys, that's what I figured

 

[zoomer0056]

Nit: its a wall connector, the charger is in the car. The breaker is for safety and is there to protect wires and equipment downstream from it. If you use a 60amp breaker you should also use a wire guage rated to handle the breaker current. Breakers are easy to replace, no need to put a 60amp one in until you need it. The wire is another story, much harder to change out. I have a gen 3 wall connector with a 60 amp breaker and appropriate wire guage (i dont remember what the guage is) for my 2022 MSLR. Like post #2 says, the current is limited to 48 amp.

 

[Tronguy]

Let’s take this from the top.

Teslas hooked up to L2 connectors like the Wall Connector get 208 to 240 Volts AC.

The interesting question is how much current the car draws.

The car talks to the Wall Connector to find out how much current it can supply. It then looks at its own navel to see how much current the car can accept. (The max on your car is 32A; but one can set the car’s charge rate to something less on the control screen. It’s still a case of navel-staring.)

The smallest number wins, and the car’s electronics draws that much, and no more. It’s the car that actually sets the actual current, nothing else.

For what it’s worth, the car also talks to the battery management system to work out limits; if one is charging to 100%, the current draw will be a lot less than 32A as one approaches that 100% state of charge. Heck, cold temperatures will reduce the amount of current the car draws, at least until the battery warms up.

So, with a SR M3, max L2 current is fixed by the AC to DC rectifiers in the car. On a LR or P, there’s three of them at 16A each, for 48A. Your car’s got two because they’re sizing the charge rate to the smaller battery and saving some money, so that’s why 32A.

So, you could do a little future-proofing by putting in a 60A breaker and wire that can handle 60A to your wall connector. You’d tell your Wall Connector that it’s on a 60A circuit. The WC will tell the car that it’s on a 60A circuit, the car will do its navel staring, and will draw 32A. Nothing broken or overloaded. If somebody shows at your place with a car that can draw 48A, then that car will draw 48A. If you buy a Tesla later that can draw 48A, you’ll be all set.

However, there’s the cost. The breaker for a 40A circuit is the same as for a 60A circuit. But copper costs serious money, so, depending upon how long the wire is between your breaker box and the WC, you might be out between $20 to $200 more for the wires capable of handling 60A than 40A.

To me, that’s not a biggie, and I’d probably go for the bigger wire/breaker, but it’s your call.

By the by: I’ve got a 2018 M3 LR in the garage and a Gen 2 WC. It’s set for a 60A circuit (48A max). But the manual for the WC mentions switch settings for a 200A circuit, apparently for early model S’s!