Re: 42 Volt Electrical Systems

[Mark Dadgar <mdadgar@xxxxxxxxx>]

Bolhuijo, Spam Warrior, wrote:
> > I didn't ask Larry how they came to choose 42 volts, as opposed to
> > some multiple of 1.5 volts as we are used to with batteries, but
> > then I'm not an electrical engineer.  I expect we'll be seeing more
> > on this in the future.
>
>  I have a guess - our good old 12V systems run at closer to 14V
> during normal operation using 6 cells.  14V/6 * 18 = 42V.  That's
> just tripling the cell count over standard.  Perhaps at rest, the

There was an article about this in a recent Roundel, as well as a  
couple of mainstream car magazines.

Apparently, the idea is to use a 30volt battery to power the starter  
motor, water pump, air-conditioning compressor, etc, and an  
additional 12volt battery to run the normal 12v appliances normally  
found on a car.

42v total, but not all on the same circuit.

- - Mark, not even playing an engineer at work
  '95 M3
  '97 528i 5-spd
- ---
Mark Dadgar
Product Manager
CoreOS, Mac OS X
Apple Computer	
mdadgar@domain.elided

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