[rescue] 48 VDC v -48 VDC...jeez!

Kris Kirby kris at catonic.net
Mon Jul 22 13:32:26 CDT 2002


On Mon, 22 Jul 2002, Kevin Loch wrote:
> > AFAIK, all telco-style DC equipment is -48V DC.  I have never seen anything
> > called +48VDC except for UPS Batteries.

> The reason for using -48dc is chemical.  High positive DC voltages
> on certain metals (like copper) tend to oxidize rapidly.

`sealing current'

--
Kris Kirby, KE4AHR  <kris at nospam.catonic.net>  TGIFreeBSD IM: 'KrisBSD'
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