[JSTARR]

I'm trying to get a grasp about the switchover from ccs (& Chademo) to NACS and compatability with Superchargers.
From superficial press hits, it at first seemed just a connector swap, which seemed like a trivial change.
Going a bit deeper, it seems to be primarily a change in the form of digital communication protocol and also regarding the mechanism for how the communications link between power supply (charger) and vehicle is transmitted/received.
From superficial research, I think ccs and also early teslas used something called the CAN bus, which is present in most ICE cars to enable systems to work together. PLC, which our cars will soon utilize, is s serial communications carried on the current conductor wires and is used in the grid & houses etc. Japanese standard Chademo is also serial and the name is an abbreviation for the expression "how about some tea" which is quicker.
If anyone has a better explanation or a link that really explains this stuff, I would love to learn more. Aloha JAS.

[Paladin1]

CHAdeMO based in Paris is actually an abbreviated form of Charge de Move, but the Nihongo pun is O cha demo ikaga desuka - "Let’s have a cup of tea while charging," or "the time it takes to have a cup of tea."

[JSTARR]

Tnx

[Pictor]

The CCS1 to NACS is indeed largely a connector swap. They both use the ISO-15118 communication standard. Older T* used to use a CAN bus based standard but they've switched to ISO-15118 several years ago. I suspect the move was largely a result of the EU requirement that CCS2 be the standard in that market and CCS2 also uses ISO-15118. There are some differences that have been raised between NACS and CCS1 and it's ISO-15118 (-20) standard and the one I keep hearing about is with support for 277v for AC charging.

277v is supported by plenty of DC CCS1 destination chargers but even the current Tesla AC wall charger doesn't show 277v as being supported - at least not that I've found. So I'm not clear on how or even if T* still supports 277v to the vehicle for AC charging and there could be problems with this which I have not run into in the wild with my own use of T* Destination chargers on CCS1 cars. I believe some Model 3 and Y cars supported 277v but that's not the same as their EVSEs support that voltage or even if the future standard would support it. It seems like something that was once considered and then abandoned.

In either case, 277v is just a single leg of a 480v 3-phase Wye feed measured from Neutral to Line (~277v=480v/1.732) used in commercial settings and it's possible to get 240v/120v from that power source. If anyone has information on how T* is using 277v for AC destination charging, I'm interested in official references (no Reddit posts please). I cannot comment on ChaDeMo.

[JSTARR]

Thanks for good explanations, guys. I'm getting closer to understanding more of this stuff.
Beautiful day up in the Catskill Mtns here. Enjoy!

[exxxviii]

One more thing to add... On the car, it is a lot more than just the connector change. The J1772 & CCS connector uses separate conductors for AC & DC. The J3400/NACS uses the same two conductors for both. Therefore, the electrical path from the port to the battery must be redesigned. This will likely mean a new onboard charger that switches in and out of the electrical path based on the charging method.

[AlanG]

Originally Posted by exxxviii

One more thing to add... On the car, it is a lot more than just the connector change. The J1772 & CCS connector uses separate conductors for AC & DC. The J3400/NACS uses the same two conductors for both. Therefore, the electrical path from the port to the battery must be redesigned. This will likely mean a new onboard charger that switches in and out of the electrical path based on the charging method.

Any idea how Ford managed the transfer? They are just sending out adapters to the installed base.

Alan

[exxxviii]

Originally Posted by AlanG

Any idea how Ford managed the transfer? They are just sending out adapters to the installed base.

Alan

Fords are not native NACS. The adapters simply route the 2 NACS conductors from the dispenser to the 2 CCS DC conductors on the car. The adapters will not work with J1772 AC charging.

[JSTARR]

Does this mean BMW's and other production BEV's will need a more complex path to using NACS chargers?
If so, what could that look like?

[exxxviii]

Originally Posted by JSTARR

Does this mean BMW's and other production BEV's will need a more complex path to using NACS chargers?
If so, what could that look like?

Yes, future cars will all need a "smart" onboard charger to go along with the NACS port. The charger will need bypass switching on the input side of the charger to redirect DC directly to the battery. Basically, they just need to mimic what Tesla has been doing for over a decade.

[JSTARR]

I had thought they could manage the switchover & other required hardware offboard, in the cable and adaptor for pre MY 2025 BEVs.

[exxxviii]

Originally Posted by JSTARR

I had thought they could manage the switchover & other required hardware offboard, in the cable and adaptor for pre MY 2025 BEVs.

Looping back to your original post, there are three major changes coming:

1. Manufacturer onboarding: This is necessary for anything else to work. This is the process of Tesla and BMW connecting their back-end computer systems so that when you plug in to a Supercharger, Tesla recognizes your VIN as a valid vehicle to charge and then allows charging. When this is done, our cars will be authorized and billed through the BMW app, not the Tesla app. Tesla and BMW are doing this sometime in early 2025.
2. CCS Adapters: Second is for all the cars with CCS charge ports, Tesla or BMW must provide adapters to enable us to physically connect our cars to a Supercharger. If Tesla follows the same pattern as with Ford & Rivian, we should be able to order adapters around the time Tesla & BMW announce that we are onboarded.
3. NACS Ports: Future cars, starting sometime in 2025 will come with NACS ports instead of the CCS ports like we have today. Those cars will be able to directly connect to a Supercharger without an adapter.

Here's some other unrelated stuff and stuff that is not going to happen.

• NACS Port Retrofit: BMW is unlikely to retrofit a native NACS port in our cars. So, we will have to use the NACS to CCS adapters for the life of our cars.
• Magic Dock: Tesla has a few thousand Superchargers equipped with Magic Dock. These are essentially adapters built into the charging stations. We can charge at any of those today if we setup an account in the Tesla app.
• Digital Communication Protocols: This is already in play. (See Magic Dock.) Tesla Superchargers have been able to speak the CCS protocol for several years.
• V2 Superchargers: We will never be able to use V2 Superchargers. Those are early versions that do not speak the CCS protocol. Fortunately, there are not as many of those and Tesla is replacing them over time with newer generation Superchargers.

[JSTARR]

1. What is likely path to back end manufacturer onboarding by BMW for IX etc? Is this a sofrware or a hardware thingy?

I appreciate these explanations and apolologize for being a bit slow & dense as this is not my sphere of expertise. But it's coming to me!

[exxxviii]

Originally Posted by JSTARR

1. What is likely path to back end manufacturer onboarding by BMW for IX etc? Is this a sofrware or a hardware thingy?

This is pure software work at galactic headquarters, not as much our cars.

When a car connects to a DC fast charger, it must authenticate and authorize the car for charging. If a BMW connected today through an adapter, which is entirely possible, it would identify itself to the Supercharger as a BMW and provide its VIN or some kind of account identifier. The Tesla Supercharge would attempt to look it up, not recognize it, and not allow charging.

The onboarding is Tesla and BMW connecting their back-end servers so that when you connect and your car identifies itself as a BMW, the Tesla Supercharger knows that BMWs are now OK, and it would call BMW and ask if this particular VIN is authorized to charge. When BMW says "yes," then the Supercharger would start charging.

It is a little more involved in this, but this is the simplified version. And, there is also an OTA update needed for our cars to support this. (At least, both Ford and Rivian pushed OTAs to coincide with the onboarding announcement.)

[Pictor]

Originally Posted by exxxviii

This is pure software work at galactic headquarters, not as much our cars.

When a car connects to a DC fast charger, it must authenticate and authorize the car for charging. If a BMW connected today through an adapter, which is entirely possible, it would identify itself to the Supercharger as a BMW and provide its VIN or some kind of account identifier. The Tesla Supercharge would attempt to look it up, not recognize it, and not allow charging.

The onboarding is Tesla and BMW connecting their back-end servers so that when you connect and your car identifies itself as a BMW, the Tesla Supercharger knows that BMWs are now OK, and it would call BMW and ask if this particular VIN is authorized to charge. When BMW says "yes," then the Supercharger would start charging.

It is a little more involved in this, but this is the simplified version. And, there is also an OTA update needed for our cars to support this. (At least, both Ford and Rivian pushed OTAs to coincide with the onboarding announcement.)

This can be done via Plug-and-charge for 2024+ MY BMW iX or via the app which would apply to all BMW iX. The app approach requires the adapter and T* to enable that in the app assuming pre-validation that the car is a BMW which probably means the non-plug and charge BMWs will only get this enabled after everyone else is onboarded first.

[Paladin1]

My guess is that Tesla will be added as a service in the MyBMW app just as Shell Recharge and EA are now for the "legacy" iXs. That will require a charging station selection and activation from the app, but not a huge inconvenience, and you can pre-load payment so no CC required. It should also allow preconditioning when you select a Tesla charger on the native route planning software when BMW updates the OS in any of its iterations.