[migbgold]

Hey all:
I have a Tesla Level 2 wall charge installed in my garage that I use for my Model X SUV. It charges at a rate of 11+Kwh pulling 48 amps of continuous load from a 60 Amp circuit. Goes through the garage 240V outlet.

I also just got an i5 M60 and no one at the BMW Center was providing me a clear opinion as to whether I should charge that with a BMW Wall Charger or simply get a J1772 adapter for the Tesla cable that can plug into the i5.

Am I correct that the Wall Box from BMW would be a lower 30 or so continuous load v. the Tesla Wall Charger at 48?

And wouldn't it make more sense to just put the adapter on the Tesla Wall Charger rather than install a Wall Box (assuming I am not interested in charging both EV's at the same time which I am not going to be doing).

Thank you for any clarification to this issue

[GT99]

Following. I have the same situation. I bought the Lectron adapter, and it's working fine.

[RichardInCA]

My hard-wired wallbox charges at 40Amps.

[LVBMW]

The BMW Wallbox max charging is 40 amps.

[scas12]

I have an Autel charger that pulls 48A and works just fine. So shouldn’t be a power problem, I just don’t know how well the adapters work.

[i5rpm]

I got the TeslaTap adapter and it works fine. On a 60amp circuit as well. I just leave it connected to my Tesla wall adapter. I don’t know the exact rate though as I can’t find a way to see it in the app or in the car….

[btlalum]

Have no idea about the BMW power connector (charger is actually in the car for AC chargers) but I use my Tesla HPWC (high power wall connector), formerly used with my Tesla S, just fine with an NACS-to-J1772 adapter. Mine is also 240V on a 60A circuit, so 48 A is the maximum spec'd using using the 80% continuous load rule. The current actually used is set by the car (Tesla and i5 M60) although the Tesla HPWC can be set to provide higher currents for cars that can accept that. Mine is neither wired appropriately for that nor are its DIP switches set to allow it. It works just fine with the adapter in my experience, given the i5 M60's 48A limit.

[essgee]

Does anyone know why the BMW chargers are 40A while the car is capable of taking in 48A (per MyBMW app)?

[SkykingUSA]

Originally Posted by essgee

Does anyone know why the BMW chargers are 40A while the car is capable of taking in 48A (per MyBMW app)?

I don't know for sure, but it could be because a 40A charger can be plugged into a wall outlet, where a 48A charger cannot. A 48A charger must be hard-wired into the wall (at least that's the electrical code where I live in California, and I suspect it's similar elsewhere in the USA). By limiting their charger to 40A, maybe they expect to sell more of them because more people may be able to (or choose to) plug it in rather than hard-wire it?

Or, maybe they got a deal from their supplier on 40A parts, but not 48A parts? Good question.

[essgee]

I’m contemplating between the BMW Wallbox (40A limit) and the ChargePoint Home Flex (80A limit). The i5 is my first and only EV at home. The price diff between the two is only $50 and actually the Bimmer one costs more as you’d expect. The wiring/installation cost will of course be higher, may be by $500, with a 60A wiring so the car can be charged at 48A. Wondering if it’s worth it. What would make the decision easy is a comparison/estimate of charging speeds at 40A vs 48A. Please share any data/thoughts. Appreciate the help.

[btlalum]

It scales pretty much as the input power.....so 48/40 -> ~20% faster (assuming your available electrical supply would keep the voltage the same). At least that's been my experience with a Tesla S and now an i5.

[RichardInCA]

Honestly, the BMW Wallbox that I have is pretty plain vanilla - if I did it over again, I might well go with a ChargePoint/other brand. They all do what they say on the tin. Honestly for home charging I think that the current rating feels less critical to me as I’m charging the car when I want not trying to do some pseudo fast charge. My office has 6kW charging which is just fine during the day when I’m at work. I routinely charge 9kW at home.

[agorski]

As mentioned in another thread on charging, if you don't need the high amperage to get to your target SOC at the time you need it, then you should probably get a lower amp charger or dial down the amperage the car takes. This is better for your battery.

The only other consideration I might mention is whether you really want yet another online account with a company that collects your data. A dumb charger like the BMW or a base model GrizzlE solves this.

[SkykingUSA]

My eDrive40 is my first BMW and first electric vehicle too. I bought a 48A charger (Emporia) and hard-wired it into the garage. I bought it before I took delivery of the car so I would be ready on day one. Initially, I thought it would be best to get the highest amp charger available so it would charge the fastest. I don't regret having that 48A option now, but after almost 5 months of electric car ownership, I realized that the difference between 40A and 48A is not very significant to me.

It's not that significant for my use case because I typically charge the car from 40% to 65% (my regular charging routine, typically twice per week) and only charge higher than that when I'm planning a longer trip. I also ended up reducing the charging Amps down to 10A to make things a little easier on the battery. The claims of charging taking 8-10 hours (basically all night) were essentially if you charge from 0% to 100%. That situation doesn't apply in a "normal" day-to-day case for me, so in a sense, when I bought the charger (before I had the car) I was concerned about what ended up being a non-issue. I rarely charge the car more than about 25% of it's capacity (40% to 65%) so it doesn't take long at all when charging at 48A. That's why I decided to charge at 10A now. I am in no rush to charge the car up and can let it run all night most times so that's what I do.

When deciding on which charger to buy, try to figure out your use case on a day-to-day basis. Will you need to use 50% of the battery capacity every day when driving to and from work, or will you need to use only 10%? Then base the amperage you need on that. I usually charge my car twice per week and don't often use more than 25% of the battery capacity for each charge.

If you're like me, you may find that it's much less of a concern than you originally thought. I am glad I have the option to charge quickly at 48A for those times when I forget to charge the car the night before, or for longer trips on short notice, but typically I charge at much lower rates. By the way, I'm happy with my Emporia charger. It always works, and it was one of the least expensive chargers on the market. The only thing I added to it was a $20 wall-mounted cable hanger and plug holder so I didn't have to cover the plug with its rubber cap every time I use it. I'd say half the time I cover it, and the other half I just plug it into the wall mount.

Cable Mount/Holster:
https://www.amazon.com/Charger-Nozzl...1zcF9tdGY&th=1

Picture of my setup:

[lilstevie]

Originally Posted by agorski

As mentioned in another thread on charging, if you don't need the high amperage to get to your target SOC at the time you need it, then you should probably get a lower amp charger or dial down the amperage the car takes. This is better for your battery.

Charging at 0.1c or 0.2c on AC isn’t going to make that much of a difference tbh. Anything under 1c, and especially under 0.5c will be largely similar in terms of impact