On 02/08/2017 05:00 PM, James Wilkinson Sword wrote:
On Wed, 08 Feb 2017 21:55:06 -0000, Phil Hobbs
wrote:
On 02/08/2017 02:46 PM, James Wilkinson Sword wrote:
On Wed, 01 Feb 2017 17:31:50 -0000, Mr. Man-wai Chang
wrote:
A small town's sudden power surge fried tech gear in hundreds of homes
Full story:
http://www.foxnews.com/tech/2017/01/...eds-homes.html
Residents in the small Pennsylvania town of Brookville must've wondered
what on earth was going on earlier this month when a sudden power surge
caused electrical appliances and gizmos in up to 1,000 homes to fry,
explode, or simply conk out.
What may have momentarily seemed like some kind of weird supernatural
happening was actually an electrical surge caused by a failed power
line
component, according to an AP report. Local media said that "damage
ranged from residents losing a refrigerator to losing all appliances in
the kitchen or losing everything in the house."
Up to a quarter of the town's 4,000 residents were thought to have been
affected by the incident, with many reporting fried computers, burned
electrical meters, and damaged power strips. Some even spoke of
fluorescent lights suddenly exploding.
When the surge occurred, the high volume of calls flooding into the
emergency services forced the local fire department to call for extra
help from three nearby facilities.
As for the local cops, the incident tripped its main office radio,
causing them to miss the first emergency calls. The first they knew
something was up was when they heard the fire trucks roaring through
the
town.
"We were fortunate that nobody was hurt," Tracy Zents, the director of
Jefferson County's Department of Emergency Services, told AP.
You should have anything expensive in a UPS.
Big help if the house burns down. 
I've heard of folks getting MOVs put in right at the meter, outside the
house. In that sort of super nasty surge, they explode and isolate the
house from the line. Never had the urge to do it myself, but it might
be good insurance.
Wouldn't a really big surge destroy the first thing it hits, i.e. the
main fuse, meter, etc?
It matters where the big arc happens, though. You don't clear a high
energy 1600-4800V circuit with a domestic 240V breaker, that's for sure.
The result is an _arc flash_, which you do _not_ want in your
vicinity, trust me. (Youtube has a lot of examples if you doubt this.)
Having a major league arc flash on a cinderblock foundation outside the
house is a very different proposition from having one in a breaker box
mounted to a wooden stud wall inside, for one thing, but I'm outside my
experience here, so I'll happily defer to any actual power engineering
types who want to chime in.
Cheers
Phil Hobbs
--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics
160 North State Road #203
Briarcliff Manor NY 10510
hobbs at electrooptical dot net
http://electrooptical.net