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Installing the Tesla Wall Connector - Output Current?

Installing the Tesla Wall Connector - Output Current?

In the installation manual for the wall connector there is a rotary switch that sets the maximum current that the wall connector is allowed to draw (based on your wire gauge used and circuit breaker size). If I go for max, using a 100A breaker and appropriate wire gauge, I can set it for 80A. Does this mean that the Model 3 will actually charge at an 80A rate? I think I read somewhere that a wall charger is limited to 32A with a Model 3. And if that's the case, why do I have an option to go as high as 80A? Does that only apply to a model X or S?

wingsy | 18. Mai 2019

I may or may not have answered my own question. According to this chart, 48A is all I can get from the wall connector for a Model 3. I have a Model3+, so I hope I can get 48A out of this thing.

https://www.tesla.com/support/home-charging-installation/wall-connector

roger.klurfeld | 18. Mai 2019

The charger is actually in the vehicle. The maximum charge rate using a wall connector is 48 amps, provided the wall charger is hard wired. If it is the plug-in variety, the maximum charge rate is 40 amps. If you use the mobile connector, version 2, the maximum charge rate is 32 amps.

kevin_rf | 18. Mai 2019

If you have a long range (310 miles, LR , LR AWD, Performance) the model 3 can charge at rates up to 48a. If you have one of the shorter range vehicles, SR, SR+, or MR you are limited to 32a.

That said, if you plan in the future going with a second Tesla (spouse, kids driving), you can daisy chain up to four wall connector off the same breaker. So a 50a or 60a breaker would make sense. Larger breakers require larger wires driving up cost.

Either way, enjoy!

EVRider | 18. Mai 2019

Model S and X with the high amperage charger (no longer available) can charge at 72A. Older Model S’s with the dual charger can charge at 80A. That’s why the wall connector supports 80A charging.

Linebet | 18. Mai 2019

@kevin_rf, I have a Model 3 LR, and it only charges at 32A. I plug into a 14-50 outlet.

kevin_rf | 18. Mai 2019

Linebet, 32a is the limit of the mobile charging cable, not the LR. The LR limit is 48a. The OP is looking at a wall connector which when setup with the correct wiring and breaker can charge at the limit of the car. 48a for LR, 32a for the rest.

Linebet | 18. Mai 2019

Thanks.

Tronguy | 18. Mai 2019

Just so we're clear on this: The charger in the car won't draw more than the maximum of (a) the amount the charger can handle or (b) the amount that the electronics on the other end of the cable plugged into the Tesla says it can handle. Finally, if the electronics on the other end of the cable Sees Something Odd (unbalanced 240 AC, 120 VAC with a sudden drop in voltage as the current goes up (signs of a small-wire extension cord) or something like that, the current draw will be dropped. That last is called a "Safety feature that is nice, but one shouldn't depend upon it if one is thinking life and limb".
So, this approach has its advantages. Suppose one puts in the wires and breakerage to handle a full-bore Model S, which can do 80A steady state and requires a 100A breaker. A Model 3 LR plugged into that isn't going to draw more than 48A because of the limit in its internal charger; the right kind of Model S will draw 80A; and a Model 3 SR will draw its max, 32A I think.
On the other hand, the bigger gauge wire costs more; there can be issues with how big a breaker one can put into a given amperage service; and so on. So, suppose one has a 100A breaker box, the electrician says it's ok for a 40A breaker, but no more; so one sets the switches for 32A max, and that's the max _any_ car is going to do plugged in there.
It's just possible to get into trouble with this scheme. Suppose that one puts in wire that's only good for 20A, sets the switches for 32A, the car tries (and maybe!) succeeds at 32A, then we all have fun watching the house burn down. So, don't do that :).

wingsy | 18. Mai 2019

If the charger inside my M3+ can only charge at a max current of 32A, then how is it that a SuperCharger can charge it at a bazillion amps?

I want to be able to see my neighbor's house lights dim when I plug in my M3.

RichardKJ | 18. Mai 2019

The Supercharger bypasses the charger in the car and feeds DC directly to the battery (tempered by some electronics). In fact a Supercharger is basically a stack of the in-car charger modules.

kevin_rf | 18. Mai 2019

In a nutshell, when you charge at 120v/240v the 32a/48a supplies in the car convert the input ac to 350-400v DC at 16-24ish amps.

The super charger is already at 350-400v DC so it bypasses the chargers and directly chargers the batteries. Either my brain is fried, or a 250kw DC charger is delivering 400v DC at 625a!!! That's meth scary.

wingsy | 27. Mai 2019

Confirmed. Wall connector max current set to 48A, M3+ charges at 32A.

Tesla2018 | 27. Mai 2019

If you have a model S with 80 Amp charging capacity, how many miles per hour of range do you get while charging as compared to a regular model without the dual chargers? At a supercharger it wouldnt make a difference. Since supercharging is free for life for most of the earlier cars, why did people spend thousands more for the dual charger if it only speeds up at home charging?

EVRider | 27. Mai 2019

@Tesla2018: The high amperage charger in my 2018 Model S charges at 72A and gives me about 52-53 miles of range per hour. Unlike the old dual chargers, the high amperage charger became standard equipment on the 100D so I didn’t pay extra for it (and wouldn’t have). Tesla discontinued the high amperage charger shortly after I ordered my car.

tedmbrady | 27. Mai 2019

I have a Model 3 long range AWD. I have the wall charger with 6 gauge wire, 60A breaker and set to "9" which is 60amp, max 48A output. So my car will get 48A if I need it to. But then I also dial it down in the car (or phone) cuz I do not need that kind of demand on a daily basis. I usually have it set to 36A.

ADinM3 | 27. Mai 2019

@tedmbrady, just curious what made you dial back the amperage and in particular pick 36A? Was it trying to be easier on battery, concern over wires heating, something else, etc? Just curious as most usually max things out.

If your 6awg wiring is not individual wires pulled through conduit (i.e. THHN, not 3 or 4 NM-B wire), then you made a good choice as 6 gauge NM-B is technically not enough to pull 48A continuous load.

tedmbrady | 28. Mai 2019

ADinM3, I have the correct wiring, I just don't need the speed at which 48A charges (although occasionally it is nice to have) vs the load on my service. 48A is not a small load, and when also running the dryer, rest of the home, etc I just don't see the need. That's all.