WTF was THAT ?!

[Jethro_uk]

Saturday afternoon, minding our own business, feeling *very* smug at having cut the grass before the threatened rain and thunder.

Suddenly, from nowhere, a *massive* thunderclap - simultaneous with a lightening flash and - worryingly - a blue flash from my home office.

Laptop is toast :(

But weirdly, *only* the laptop. No other sensitive electronics affected (that I know of).

My working theory, is the laptop was the only device powered by an unshielded transformer (laptop was on power supply at the time). All other stuff is either SMPS or shielded in a PSU cage.

Second most spectacular lightening strike I've ever seen. The most impressive (again, came from nowhere) was on Harrow Hill in the 1980s. Hit about 50 metres from us and split a tree in two ...

[Bob Eager]

Best one for me was at a garden party. It started to rain and a load of people decided to shelter under trees (we went for a tent).

Massive strike and they went down like ninepins. Luckily there were plenty of ambulances (about half a dozen) on site and a fair few were carted off. No one was seriously hurt, although two people had superficial burns.

So many ambulances? Buckingham Palace!

[Brian Gaff]

Sounds like it struck the mains supply. is it overhead down your way?

Mind you, some years back I was working under a table with the end of a long wire receiving aerial, trying i to bring it back through a hole, when there were sparks and crackles dancing all over the place. I felt nothing but same tingles, and yet the bang from outside was very loud. My feeling was that what I had was an induced voltage due to the nearby discharge. Made a not to fit a spark gap device. :-)

Brian

[Jethro_uk]

We have lots of pylons :)

As I say, nothing else was damaged. I have a server PC running 24/7, a desktop - all fine. 2 wireless routers and 2 cable modems - all fine.

Not bothered about replacement (it's a work one, so they can figure out how to record it). Just a PITA as I have to go into the office. Hopefully they can swap the HDD over, and send me on my way. Otherwise it'll be a few hours having to retweak it to how I like (starting with a left handed mouse).

Back in the 1990s, we had an early wireless phone which died after a thunderstorm. Careful re (cough) reading of the instructions revealed it should have been unplugged in the event of an electric storm.

[T i m]

OOI, was the laptop (router, networking kit) plugged into a surge-protected outlet? If so you may have some financial / insurance cover from that and if not, why not (not that I'm suggesting it would have guaranteed survival of any kit plugged into it etc)?

FWIW, most of the 'sensitive' kit here is plugged into surge protected trailing leads and the only things I've ever had damaged (so far) were dial-up modems and answering machines that were damaged though impulse noise via the (overhead) telephone lines.

Might not have had a strike as near as yours mind. ;-)

Cheers, T i m

[charles]

But not while the storm is in progress. You might get a strike while you are unplugging.

[Tim Streater]

It's God's punishment for your inability to spell "lightning".

[The Natural Philosopher]

Only the laptop isn't properly earthed.

[Jethro_uk]

Annoyingly not :( It was plugged into the block *next* to the surge protected one (whch may explain the survival of the desktop PC). And of course, the server PC has a UPS ...

[Jethro_uk]

Guilty as charged ...

[Davey]

I once worked for a site manager who had been struck by lightning. It had left him with no sense of hot or cold, we would be sitting there in coats, gloves and hats, and he would be happy in shirt sleeves, not realising that he was getting colder and colder. He was a terrible site manager, too!

[T i m]

Ok, and like I said it may not have made any difference (other than possibly not having to contact your house insurance)? That said, I've never tried to claim on any of these surge protector insurances to know how good they are.

I'm not sure that counts

It's possible I guess.

'Of course'. ;-)

Cheers, T i m

[Jethro_uk]

It's a work laptop, so they can suck it up :)

What's the point of a "server" that goes down with the power ? Especially if it's job is to run household security (which is isn't, but it *might* be) :)

[Timothy Murphy]

...

I've often wondered if it isn't possible to have an anti-surge device on the house supply itself?

[T i m]

A bit like company cars that can run flat out with no oil. ;-)

Well, quite, unless it comes back up ok afterwards. Unfortunately it's one of those roudtuit jobs here. The Mrs PC is on a UPS, my second WHS is on a UPS (when on) but the primary server (WHS V1) has been there for a few years now and isn't (when I know it should be and I even have one here doing nothing). ;-(

Quite. ;-)

Cheers, T i m

[Bob Eager]

One of ours runs the doorbell and the front door lock (yes, there is a manual override).

[Mike Tomlinson]

En el artículo , Jethro_uk escribió:

You may now find your surge protector is no longer effective, having sacrificed itself to a surge from that strike but still allowing power through.

Some of them have a light on them to say "protection working" or similar wording - I wouldn't take that for granted.

This is a pic of two surge-protected 4-way socket strips that I removed from an installation on top of a dormant volcano in the Canary Islands following a storm. The mains up to the top is 33kV carried on pylons and somewhat unreliable. The building in which the equipment is located is metal-framed and notionally earthed, although read on.

Note the two neon indicators on the left. One is "power on", the other is "surge protection working". Both were still lit :)

After that, I spent a lot of money on improving earthing and installing UPS. There are limits to how good an earth you can get on solid volcanic bedrock though :)

[Mike Tomlinson]

En el artículo , Timothy Murphy escribió:

It is. They're big, bulky and expensive though, so it's a balancing act deciding whether it's necessary for an individual house: its location, the type of supply and the value of the stuff inside plugged into the mains.

In towns and cities with mostly underground supplies it's probably not cost-effective. In dwellings or buildings with long overhead supplies (and ugly pole-mounted transformers, e.g. the US), it's pretty much essential.

(we're straying dangerously close into to w_tom territory here...)

[The Natural Philosopher]

'surge protectors' are totally useless at real lightning strikes, a arguably are less effective than the SMPSUS they are typically there to protect.

[Mike Tomlinson]

En el artículo , The Natural Philosopher escribió:

They're not intended to protect against lightning strikes. Nothing can do that except God, always assuming you believe in Her and she hasn't woken up with a severe case of PMT.

Depends on the PSU. A decent one with MOVs wired in common rail mode and an input filter, yes. A shitty Chinese one built down to a price, no.