[58692] in North American Network Operators' Group
Re: "They all suck!" Re: UPS failure modes (was: fire at NAC)
daemon@ATHENA.MIT.EDU (David Lesher)
Thu May 29 22:02:39 2003
From: David Lesher <wb8foz@nrk.com>
To: nanog@merit.edu (nanog list)
Date: Thu, 29 May 2003 21:59:38 -0400 (EDT)
In-Reply-To: <Pine.LNX.4.44.0305291619090.27497-100000@sasami.anime.net> from "Dan Hollis" at May 29, 2003 04:19:52 PM
Reply-To: wb8foz@nrk.com
Errors-To: owner-nanog-outgoing@merit.edu
Speaking on Deep Background, the Press Secretary whispered:
>
>
> On Thu, 29 May 2003, Sean Donelan wrote:
> > The most annoying thing about UPSes is they fail at
> > exactly the time they are needed most.
....Like tape drives..
> ok, what UPSes do telcos use (besides their monster battery arrays)
>
> -Dan
They eschew same. Telco stuph runs on that -48v. It's their steak
& potato...err E.
But the price is high and not just the cost. A telco string stores
enough to qualify as weapons of mis destruction. Drop a wrench
and learn Braille. You need a PE with a track record in battery
plant design. You need a separate room, separate ventilation,
separate entrance, etc.
But your MTBF is many years. Yes, you lose individual loads,
but the string carries on. Provided, of course, you keep the
rectifiers running, and know when they fail...and fix same. (ATT
NYC Toll switch and DACS...)
--
A host is a host from coast to coast.................wb8foz@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
