In article et,
"Dave Liquorice" writes:
On Sun, 7 Jun 2009 14:01:51 +0100, tony sayer wrote:

Could it be that a circuit breaker opened and auto reclosed that
quickly?

Seems a tad quick for an auto recloser.

I rather think that the current flow wasn't that much, well on the scale
of the power that the OHL can supply.

I'm not thinking of a trip of the breaker due to overload but due to earth
leakage.

The circuit is earth return (track), so you can't measure earth leakage,
as it's not insulated from earth.

The auto recloser on the 11kV that feeds us trips on earth
leakage. One of the insulators starting tracking over on the top of the
pole outside, we wouldn't have known if we hadn't been oustide and heard
it crackling, enough to make the auto-recloser cycle through it's three
trips in x minutes = lock out. I think we would have been aware of the
noise from inside the house if it was overload that close causeing the
trip...

I used to have an 11kV insulator I found on a walk in the countryside.
It had a very thin metal flash line over the outside of it, and was
presumably disposed of into the nearest hedge by whoever replaced it.

Theres been a lot of debate over on UK Railway as to whether or not a
video such as depicted there should be used as a public info film to
warn of what can happen if you should touch those harmless looking
wires..

It's certainly an idea but not for "general release" maybe part of a
targeted campagne within schools in areas where playing on the electrified
railyway is a problem. I think the teachers would have to be told about
and consulted before hand and some form open discussion held afterwards to
talk about it.

A friend (who isn't Internet-savvy) had a teenage child who was about
to start riding a moped, and he wasn't happy about it. Several of us
talked about it at work. I went browsing on the Internet and found
several photos of motorcycle fatalities, the idea being that his dad
would only let him on the moped after he'd gone through some of these
with him, basically to show a teenager who (like any teenager) thinks
they're indestructable, just how fragile life really is. That was 4 or
5 years ago, and about 2 years afterwards, the teenager lost a friend
in a car crash (which he wasn't involved in). He remarked to his dad
that the session with the motorcycle fatality photos had quite an
impact on him, and he thought about it each time he saw a friend doing
something stupid on a bike. (The site was ogrish.com, but it's now
gone and the name points somewhere else.)

I can't help thinking that the wrapping people in cotton wool that we
do in this country (i.e. protecting them from images of such realities)
may well result in more such incidents due to widespread ignorance.

--
Andrew Gabriel
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