Question

Is it necessary to remove the plug of a pc/router from the wall socket when
the threat of lightening strikes ?

Aries...

but why?

pmj...

It's not actually *necessary*!!!...

Though it may well be advisable, depending on your assessment of
the Risks & the possible costs/inconvenience involved.

See my other Reply as to what *can* happen, when there's a very large
Spike/Surge in the Mains, caused by a Lightning Strike on a nearby
Electricity Sub-Station.

Flyiñg Ñuñ 2°°6 +...

Ooooops!!!!!!! :(

pmj...

It depends whether you mind the Router getting Damaged if there's
a particularly heavy Surge or Spike - or even getting completely
"fried" if there's a direct Hit.

It's a question of risk assessment & weighing up the risks,
(& the benefits & disadvantages & costs) in your particular situation.

pmj...

If you have the Router (& any other equipment that is Connected to
the Mains Supply) Connected through a "Surge Protector" then that
*can* help Minimise the chances of damage, but it can't eliminate
them completely.

& also, there's always the possibility of a Surge or Spike coming
in through the *Phone* Line, so you would need to UnPlug the *Phone*
Cable from it as well, to be sure of full protection.

I've never UnPlugged any of my equipment during any Thunderstorms
(& we get quite a few around here) & in about 8 or 9 Years I've only
ever had *one* problem due to Lightning...

That was in 2000 (or was it 2001?) & The Electricity Sub-Station just
round the corner got hit & there was a *huge* Surge/Spike through our
Mains & it burnt out the Motherboard, Processor, Graphics Card & (Dial
Up) Modem in my PC.

They were easy enough (though not very cheap!) to replace, but it
meant that the PC was out of action until I was able to replace them,
the next day.
:-(

Aries...

Personally I always remove plugs to my pc and router during a thunderstorm

pmj...

& do yo ualso Remove (UnPlug) the *Phone* Line Connection to it?

but my friend wants to know why just turning off the switch isn't

Saxman...

Add your telephones to that as well! You will be charged for repairs
on equipment owned by you, but insurance companies sometimes pay.

pmj...

Well - a Flash of Lightning is several *Million* Volts & also several
*Million* Amps of Current!!! - More powerful than *any* man Made
Electrical Source.

Jeff Gaines...

No way pmj!!!

Voltage may certainly be in the order of millions of Volts but not
current, 500,000 Amps peak current is nearer the mark. Still enough to

pmj...

OK, so not "several Millions" of Amps - but "half a Million" Amps.

Thanks for the correction.

Half a Million Amps is still a lot though, isn't it?

pmj...

Yep!!!

& also to make anything that is on the receiving end of it
comprehensively Brokted!

give you a tingle.

Have a look at:

& mere *Switch* (with what is usually just a 3 mm Gap between the
Contacts) won't Stop a Bolt of Lightning getting through, will it?

At least if the stuff is physically UnPlugged (Disconnected),
then the Lightning won't be able to get through - unless it's a
direct hit, in which case the damage to the Modem/Router/PC will
be the least of your worries!

Aries...

I'll pass that on to my friend as that is the best explanation I've seen so
far. Personally I always unplug even when I go out for a couple of hours
just in case.... Thanks PMJ

sufficient.?

datasmog...

Do you also unplug the televisions, radios, clocks, and any other
domestic appliances, fridges, washing machines (especially dangerous as
they are also connected to the water main) for example? Have you ever
seen a light bulb explode? Might be a good idea to remove all those as

Ali...

Replacement cost of lightbulb - 60p
Replacement cost of computer - £500-£2000

well.
;-)

Aries...

TVs yes but the others no LOL

andon...

If you see a house hit by lightening you may well notice that all the
electrical fitting are blown clear out of the plaster/wood. That the
nails have been forced out of the plaster board and sprayed around
the rooms. A house near us even had the nails ripped out of the
floorboards :-(

Aries...

I do know of somebody who had their house so badly damaged by lightning
they had to move out for 6 months whilst it was being repaired. The wife
was ironing at the time :eek:

andon...

What ! For the whole six months?

Aries...

LOL ;)

As has been stated above.... it is down to personal assessment of
risk. How many houses have you heard of being hit like that one? It
is the only one I know of. I have heard of the odd few over the years
via TV & media. Compared with the number of houses in the UK, it must
be pretty rare.

As for surge protection, a good UPS or even surge-block will have
phone line protection sockets too. I am sure that if your friend was
using such a device any damage that was not contained by this would
be considered by an insurer as "beyond reasonable precaution".
However, I would check with the insurer. It has got to be worth the
call for the peace of mind.

The most common risk is from these big surges/spikes. Either overhead
power-lines or sub-stations getting hit are the main culprits.

Ali...

Two reasons:
1) the surge can come along the 'neutral' wire - that isn't switched.
Actually, it can come along all the wires.

2) the switch isn't going to stop the surge from a lightning strike anyway.

Aries...

thanks Ali - :)

BoyPete...

Don't rely on surge protectors. They cannot handle the thousands of volts of
a lightening strike.

Aries...

I don't use a surge protector, I remove the plugs, just wanted to know why

BoyPete...

A lightningh strike on your house, or any part of the electrical, or
telephone connection to your house, WILL result in your computer and
router/modem being fried.

Smokey...

Val my friends modem was fried last year along with many others in the
village during a storm. The local pc repair shop did a roaring trade

Aries...

Did she switch off the plug and remove it tho? I'm asking this on behalf
of a friend who wants to know the reason for actually removing the plug :)

Aries...

so just switching off the plug is not sufficient. ?

w_tom...

Lightning seeks earth ground. It will find earth via a path you
provide before getting into the building, or it will find destructive
paths via your appliances. Will those little contacts in a switch
separate to stop what 3 miles of sky could not?

Aries...

Thanks for the advice, links and for replying to my question, much
appreciated :)

Nothing is going to stop, block, or absorb lightning. That also
applies to surge protectors without an earthing connection. Ben
Franklin did not try to stop lightning to church steeples. Franklin's
solution also gave lightning an electrically shorter path to earth.
The effective solution shunts (diverts, connects, rechannels) lightning
on a shorter path to a superior earth ground. It applies to lightning
rods, to surge protectors, or to incoming utility wires that are
connected directly to earth with nothing but a ground block and short
wire.

Earthing is what a 'whole house' type protector does. Unlike plug-in
types, the 'whole house' solution provides a shorter path to earth.
Lightning that does not enter a building (instead earthed at the
service entrance) will not find destructive paths through household
appliances; will not overwhelm protection already inside all
appliances. Examples of effective solutions:

Early 1900 Ham radio operators would disconnect antenna leads and
still suffered lightning damage. Damage in the Ham Shack stopped when
those antenna leads were earthed.

Problem with being dependant on disconnecting or switching off is
dependency on a very unreliable actor - the human.