Gentlemen: The IEEE 1159 Power Quality Standard for Commercial & Industrial applications a good standard to help avoid downtime due to power outages, sags, surges, and related. Search Google for :IEEE1159.1. IEEE1159.2, IEEE1159.3 and IEC 61000-4-30 for standard which provide the methodology for assessing power-quality factors and indices.
This link will provides general education: http://grouper.ieee.org/groups/spd/ This link will help you calculate ROI should you decide to spend valuable capital on mitigation equipment: http://grouper.ieee.org/groups/1346/points.html I had the opportunity to work with PQ guys in the 1990s and their/our work helped establish a new standard at SEMI. http://powerstandards.com/cbema.htm The Point: Typically a "sag" of 60% of nominal voltage will be "seen and felt as a power outage" by most electrical components. Therefore a "zero voltage" condition is not needed to experience a power outage. All that is needed to create a "zero voltage or power outage experience" is a 60% of nominal voltage which is enough to shutdown your equipment. http://ecmweb.com/mag/electric_postmortems_vs_predictions/ Most of the WISPs I work with have either some kind of back up. In the United States most I see is APC or Exide UPS systems. But it is one thing to have UPS and another to have UPS+Power Conditioning. . Summer is coming around in the US. Highly constrained distribution systems may experience some downtime. I've always been interested in "downtime" statistics for big WiSP, medium WiSPs, and smaller WiSPs. I'm sure this is some hat compete information and the downtime not only due to electrical issues. There is also network downtime, software downtime. etc. One commerical carrier funded an interesting report that compared uptime of commercial wireless networks versus uptime of a traditional IP network (LAN not wireless). Thanks for your time, F.Lopez --- "Edward H. Winters" <[EMAIL PROTECTED]> wrote: > Looks real to me ... > > http://www.nac.net/announcements.asp?Action=View&ID=83 > > ** Update ** > > 6/22/2007 - 12:45am > > Our Cedar Knolls Facility (MMU) is no longer running > on generator power. > Utility service has been restored. All systems are > functioning normally and > no disruption in power occurred at MMU. > > The Parsippany data center (OCT) is still running on > generator power while we > resolve a problem at that site. > > --------------------------------------------------------------------- > > 6/21/2007 - 10:30pm > > We have experienced a power problem caused by > lightning in our Parsippany, NJ > (OCT) Data Center. This location is currently > running on generator power. > If you are having any problems with your server > please call our Network > Operation Center Directly at 973-590-5050. > > In addition our Cedar Knolls Site (MMU) is also on > Generator Power but has not > experienced any problems. > > Ed > > On Thu, 21 Jun 2007 23:50:14 -0400 > Michael Erskine <[EMAIL PROTECTED]> wrote: > > > DSLR's Excuse for being off line.... > > > > Thu Jun 21 21:58:42 EDT 2007 > > ================================================== > > DSLR is offline at the moment, total power failure > at the > > data center we use (www.nac.net) an hour ago means > we have > > to bring servers up individually, and check for > errors. > > > > update: > > Thu Jun 21 23:09:54 EDT 2007 > > Looks like this is going to take hours to sort > out > > and we're off to do an all nighter at the data > center :( > > > > > > Link to nac... Which was working at time for > post? > > > > http://www.nac.net/ > > > > Which part of power outage is an excuse? The part > that > > was spelled subpoena? > > > > Ayup, twice in as many years.. > > > > > > > > > > -- > > WISPA Wireless List: wireless@wispa.org > > > > Subscribe/Unsubscribe: > > http://lists.wispa.org/mailman/listinfo/wireless > > > > Archives: > http://lists.wispa.org/pipermail/wireless/ > > > -- > WISPA Wireless List: wireless@wispa.org > > Subscribe/Unsubscribe: > http://lists.wispa.org/mailman/listinfo/wireless > > Archives: http://lists.wispa.org/pipermail/wireless/ > ____________________________________________________________________________________ Yahoo! oneSearch: Finally, mobile search that gives answers, not web links. http://mobile.yahoo.com/mobileweb/onesearch?refer=1ONXIC -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/
