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Tesla shares 48V architecture with other automakers

electrek.co

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Re: Tesla shares 48V architecture with other automakers

#361

Post by brnt »

jdewerd wrote: post #338
DannyBee wrote: post #272

Earlier quoted context omitted.

48V has been considered for automotive for decades. The problem was not know how. It simply has never been worth it before to retool things in practice. It's also electrically a lot more noisy. The limit of what is considered low volt is like 60v or something.

It was never worth it to retool for decades ? Or was there a pathological lock-in between suppliers and manufacturers that prevented even the most obvious innovations from happening if they required any amount of coordination?

Try counting the number of businesses involved in making a vehicle.

Re: Tesla shares 48V architecture with other automakers

#362

Post by RF_Savage »

hulitu wrote: post #354
DannyBee wrote: post #272

Earlier quoted context omitted.

48V has been considered for automotive for decades. The problem was not know how. It simply has never been worth it before to retool things in practice. It's also electrically a lot more noisy. The limit of what is considered low volt is like 60v or something.

> The limit of what is considered low volt is like 60v or something. As far as i know, 60 V is the limit for alternating current. For DC it is 24 V.

Depends on the region. 56V AC and 72V DC here. -48V has been the standard voltage in telecoms for +100years, so 48V systems and parts are not that exotic.

Re: Tesla shares 48V architecture with other automakers

#363

Post by TheLoafOfBread »

andrewf wrote: post #355
TheLoafOfBread wrote: post #121

Earlier quoted context omitted.

Ethernet can be used as a bus (see CSMA/CD), but if there are more than 2 nodes, performance of whole bus will go to complete shit and there is no guarantee that an ECU will transmit a single packet during its run, because that CD has no automatic arbitration, it is just random disconnection and try again. Not good for critical things like ABS. That's also whole reason why FlexRay was spawned, because even that FR is…

I think that's what 10BASE-T1S (standardized in 2019) is for. It has a non-CSMA/CD arbitration scheme. https://www.electronicspecifier.com/industries/industrial/an...

So... you need new PHYs and new Ethernet controllers to use T1S?

Re: Tesla shares 48V architecture with other automakers

#364

Post by MrBuddyCasino »

mmaunder wrote: post #246

Many comments here seem to be confusing the accessories circuit voltage with the electrical vehicle motor and drive system. The vehicle motors have a combined power output of 450KW which requires a high voltage 800V system or the wiring would be so heavy it would not be feasible. This spec appears to be the accessories circuit with Tesla pushing for a new 48V standard. That’s super smart because it immediately means…

48V is also currently used on the supporting electric traction motor of "Mild Hybrid" cars.

Re: Tesla shares 48V architecture with other automakers

#365

Post by TheLoafOfBread »

eglretgj wrote: post #344
yinser wrote: post #39

I liked the interview with auto engineer Sandy Munro discussing the change https://youtu.be/ADwGGEj8sqQ?si=qp6akvy1yyWPTYNe - moving the voltage up means you can drop current - increase the data rate by using ethernet and PoE - using ethernet and PoE means you don’t have to run one off wires to each device, they can share a bus which results in half the copper being used in a lower voltage car - moving the voltage up…

I work for another EV manufacturer. Good God I would love to switch from CAN to ethernet. We already have way too many CAN buses and we're considering adding more. But it will take decades for our suppliers to even consider the switch. We just paid Bosch $15M for an upgrade to our brakes, they promised the change in six months, it took them two years and quite a few additional millions of dollars, and it's filled wit…

Well, then you should maybe ask why do you need such complexity, when cars 5-10 years did not needed to do exactly same task - taking a person from point A to point B.

Re: Tesla shares 48V architecture with other automakers

#366

Post by 0xDEAFBEAD »

jmrm wrote: post #141

>48V architecture also potentially improves overall electrical efficiency for reasons that I am not sufficiently qualified to explain beyond a kindergarten level This is double bad in a green energy and EV website: On one hand, they admit they don't now why that happens, but on the other hand, they also didn't research just a bit more on that, and that's bad journalism. Most of the comment threads in this HN post are…

>Most of the comment threads in this HN post are a lot more informative than the article

To be fair, how many commenters on HN would accept a job in journalism if it was offered to them?

We're lucky that so many qualified people share their takes for free on this website.

Re: Tesla shares 48V architecture with other automakers

#367

Post by yetihehe »

klysm wrote: post #307
horacemorace wrote: post #280

Earlier quoted context omitted.

Faster slew rate for all switch supplies in the system. Nothing directly runs 48v.

I’m still skeptical. Why can’t it be filtered out

It can, it just requires up to a dollar more per device.

Re: Tesla shares 48V architecture with other automakers

#368

Post by szundi »

user_named wrote: post #321
mmaunder wrote: post #246

Many comments here seem to be confusing the accessories circuit voltage with the electrical vehicle motor and drive system. The vehicle motors have a combined power output of 450KW which requires a high voltage 800V system or the wiring would be so heavy it would not be feasible. This spec appears to be the accessories circuit with Tesla pushing for a new 48V standard. That’s super smart because it immediately means…

"super smart" - more like completely obvious to everyone for decades

That’s what Elon said, no innovation, just made the step

Re: Tesla shares 48V architecture with other automakers

#369

Post by lmpdev »

mmaunder wrote: post #246

Many comments here seem to be confusing the accessories circuit voltage with the electrical vehicle motor and drive system. The vehicle motors have a combined power output of 450KW which requires a high voltage 800V system or the wiring would be so heavy it would not be feasible. This spec appears to be the accessories circuit with Tesla pushing for a new 48V standard. That’s super smart because it immediately means…

I get this a lot

I work at an electronics store in Australia

This week I had a customer dumbfounded why his 3,500W inverter almost caught fire

He was using 8-gauge wire (~56A max)

He needed 00-gauge (almost 300A max)

If he’d have run the system at 48V instead of 12V he’d have saved $200+ per metre on cabling his inverter

My advice on voltage selection for a vehicle is once you’re needing more than a few metres of 0-gauge, you should possibly increase the voltage of the system

High current cabling means expensive ANL, mega or other high performance fuses or other expensive circuit protection methods

I strongly believe that 48V systems are inherently safer than 12V systems when it comes to the public doing DIY work

Re: Tesla shares 48V architecture with other automakers

#370

Post by SilverBirch »

erupt7893 wrote: post #227
SilverBirch wrote: post #147

Earlier quoted context omitted.

Hi, excuse me. Just want to say, don't appreciate you rounding me up with the anti-semites. "We humans". No - those anti-semites, and us reasonable people. Wouldn't like to mix with them thanks. You can make whatever excuses you want for him, but that's what they are, excuses.

This is silly, don't stand on some high horse. If you don't think you have the capability to be unreasonable, you are delusional. Every single person on this planet is capable of evil, but majority luckily see that as a path that ends badly.

I think there's a bright bold line between me and the anti-semites and I think that you're doing the work of the anti-semites to pretend there's not. Everyone is capable of evil. Some people actually do evil things though and some people don't. The issue here isn't what people are capable of, it's what they're doing, and Elon Musk is endorsing crackpot anti-semitism on the platform he owns in the aftermath of the largest attack on Jews since the holocaust.
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