DC power versus AC power
owen at delong.com
Mon Dec 30 03:09:50 UTC 2002
Absolutely. Often, there are more than a few hundred amps available.
Remember, many of those switch rooms were built to specs to drive a very
large number of solenoids, relays, etc. All relatively high-current
devices compared to today's solid state stuff. Alot of the specs were
never reduced, the rooms just got bigger, and the number of customers.
There's a reason the backbone is multiple copper plates and not just
--On Sunday, December 29, 2002 5:40 PM -0800 Scott Granados
<scott at wworks.net> wrote:
> Is 48V DC at the amps present normallyin switch rooms etc enough to cause
> electricucian? I have seen bad things with wrenches dropped across
> batteries even 12 volt car batteries although in this case it was a large
> battery bank in a submarine but I was curious about the 48V sources in
> switch rooms.
> ----- Original Message -----
> From: "David Lesher" <wb8foz at nrk.com>
> To: "nanog list" <nanog at merit.edu>
> Sent: Sunday, December 29, 2002 4:43 PM
> Subject: Re: DC power versus AC power
>> Unnamed Administration sources reported that Michael Painter said:
>> > > > But, as Stephen already eluded to... Compared with an AC plant
> design, to
>> > me, one of the biggest drawbacks of a DC plant is safety (I have had
>> > to kick a fellow worker away from the rack before). <<
>> > What was the worker doing? Is this 48 VDC?
>> Bet so.
>> And note, it's not just ISP's, of course. I heard that Sprint
>> PCS ha[s,d] a Dallas tech in critical condition and a dead switch
>> after a dropped wrench & resulting fire.
>> In the words of Phil Esterhaus:
>> Let's be careful out there....
>> A host is a host from coast to coast.................wb8foz at nrk.com
>> & no one will talk to a host that's close........[v].(301) 56-LINUX
>> Unless the host (that isn't close).........................pob 1433
>> is busy, hung or dead....................................20915-1433
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