New 42Volt systems

[Rob Weinstock]

>-> There's also the old safety and licensed repairers problem for DC
>-> equipment, you can't go above 48Vdc before you need trade licences to
>-> start working on electrical equipment.  Of course, rules in the US
>-> may be different.
>
>  I don't see any bright yellow "WARNING!" stickers on the coil or plug
>wires, which run at ~20,000 volts.  Most modern electronic ignitions put
>out enough amperage to knock your socks off too.

True, but there isn't enough current in that application. Now, 48 Vdc from 4 
car batteries can put out 2000 amps briefly. Also, dc current is way more 
difficult to interrupt than ac current - you can open a switch and the 
current can continue to flow across the gap. So the risk is from either 
electrocution or a very nasty plasma burn if you happen to be in the 
vicinity of a short. I used to be a plant engineer for a large chemical 
company. They had a fatality due to a shorting 48 vdc battery system -- this 
was a room sized system. Once the short occured, there was nothing they 
could do until the battery charge depleted itself.

My feeling is that distribution systems in vehicles will remain 12 Vdc for a 
very long time. Specific accessories that require a higher voltage source 
will likely incorporate an internal boost converter, sealed from probing 
DIY'ers.

Regards,

Rob
_________________________________________________________________
Get your FREE download of MSN Explorer at http://explorer.msn.com

----------------------------------------------------------------------------
To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes)
in the body of a message (not the subject) to majordomo at lists.diy-efi.org