[29303] in North American Network Operators' Group
Re: Summary: Bay Area Power (2000-06-14)
daemon@ATHENA.MIT.EDU (John Hall)
Fri Jun 16 15:35:16 2000
Message-ID: <394A829B.E74F4ADF@f5.com>
Date: Fri, 16 Jun 2000 12:40:11 -0700
From: John Hall <j.hall@f5.com>
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To: Jim Browne <jbrowne@jbrowne.com>
Cc: nanog@merit.edu
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When you lose a part of a multi-phase circuit, you usually get bleed
through enduser devices that are still getting power through the other
phases. Your 27VAC was probably bleen through a (or more likely several)
three-phase motors that did not have phase-outage protection circuit
breakers. They probably had stopped spinning and were slowly cooking
themselves. A building I once worked at lost one of their phases and
after an hour the fire alarm went off and we had to evacuate the whole
10 stories. A "temporary" compressor in a design model shop did'nt have
adequate protection and cooked all it's lubrication, filling the shop
with smoke. Apparently, phase-outage protection is not required in
many installations where it should be. One data-center in the same
building still had some three phase powered mini-computers (mini in
name only) and they lost almost half their hardware.
JMH
Jim Browne wrote:
> Downtown Sunnyvale around Carroll Street (including PacBell SNVCA01
> and us) lost power (on one phase only) yesterday at 12:35 PDT. PG&E
> brought it back at 15:35. PG&E said that our area is using too much
> power and we blew the breaker on that phase. The odd thing was we
> were still getting about 27 VAC on that phase with the breaker
> "blown".
--
John Hall <j.hall@f5.com> F5 Networks, Inc.
Senior Test Engineer 206-505-0800
One of the large consolations for experiencing anything unpleasant is
the knowledge that one can communicate it.
-- Joyce Carol Oates
