[FoxNews]A small town's sudden power surge fried tech gear in hundreds of homes

[Mr. Man-wai Chang]

A small town's sudden power surge fried tech gear in hundreds of homes

Full story:

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.

[James Wilkinson Sword]

You should have anything expensive in a UPS.

[Phil Hobbs]

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.

Cheers

Phil Hobbs

[James Wilkinson Sword]

Wouldn't a really big surge destroy the first thing it hits, i.e. the main fuse, meter, etc?

[Phil Hobbs]

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

[David Lesher]

The Washington Post had some great photos of a house with every outlet and switch blown out of the walls.

Seems there was a FIOS installer trenching there when it happened. The WP didn't say, but from the imagery, I suspect they crossed the 34KV feed to the pictured pad-mount transformer with its 240/120 output.

It was news because Verizontal refused to pay; saying it was the contractor's fault not theirs.

[James Wilkinson Sword]

Which it was. But the contractor should have to pay, and Verizon has to pay in the interim, just as if you order something online and it's lost in the post, it's the postal company's fault, but you still claim from the seller, and the seller from the postal company.

[David Lesher]

Have you ever won an argument with Verizontal?

[CRNG]

This thread reminds me of a surge protector question I have.

I have a Tripp-LIte surge protector

It has two "filter banks": one marked (50db) and the other (75db). What do those number mean? Different levels of surge protection?

[Mike Rotch]

The Isobar has internal barriers (isolated filter banks) that prevent line noise from causing A/V distortion, computer lock-ups, data errors and similar problems. Filtering is accomplished by combining toroidal chokes, ferrite rod-core inductors, HF/VHF capacitors and layers of metal oxide varistors into isolated filter banks that remove EMI/RFI interference.

[CRNG]

On Sun, 12 Mar 2017 10:13:05 -0400, Mike Rotch wrote in

Oh, thanks very much Mike. I know very little about electronics. BTW, which provides the greater barrier to line noise: the 75db I presume?

[Ralph Mowery]

The higher the DB, the greater the barrier to line noise is correct. With out a refference the db does not give much information. It should be refferenced to something like milliwatts or millivoltes.

The 25 db of difference is about 300 times as much, but with out a refference that number does not mean much.

[CRNG]

On Sun, 12 Mar 2017 06:17:48 -0500, CRNG wrote in

Thanks again to Mike and Ralph for the comments.