Turn off computer during thunderstorms?

[Mulreay]

Very true to both Patio and Kpac but we rarely get the storms of which you speak in England so my computer stays plugged in no matter what. I suppose it depends on population and building density.

[smeezekitty]

No matter what type of connection you have the power and any network connection should be unplugged...

agreed
fried a modem that way
had it pluged into phone line and there was a fair amount of lightning outside
next day the modem didnt work

[Quantos]

Population and building density don't make much of a factor.  Where you are the weather just doesn't build up to lightning very readily.

[kpac]

Very true to both Patio and Kpac but we rarely get the storms of which you speak in England so my computer stays plugged in no matter what. I suppose it depends on population and building density.

Heh, we had a storm here today just over the water...

[patio]

We tend to get huge TStorms here...and lot's of them...
Even in the dead of Winter ...which is rare.

[Quantos]

We tend to get huge TStorms here...and lot's of them...
Even in the dead of Winter ...which is rare.

That's what it used to be like in Ferny.

You're in Quebec right?  Are you guys planning any major ice storms this year?

[Mulreay]

Heh, we had a storm here today just over the water...

Where are you Kpac?

[Salmon Trout]

extreamly unlikely
but impossable to be never

The Empire State Building gets struck around 100 times a year.

[Mulreay]

The Empire State Building gets struck around 100 times a year.

I think most people don't live up as high as the empire states building though!

[kpac]

Where are you Kpac?

Over the water? Approximately 26 miles at closest.

[soybean]

I have a computer here that belonged to a friend.  It was in use during a storm and it was ruined by a power surge. I believe they were not using a surge protector on it but, of course, even surge protectors can only offer a limited degree of protection.

My mother's older computer had an internal dialup modem ruined by a storm, even though the telephone line was routed through a surge protector with phone line protection.  Fortunately, no other components were damaged. 

Aside from thunderstorms, power fluctuations can be caused by other factors.  I live in a community which has grown rapidly in the last 15 - 20 years.  I believe construction activity, particularly the connecting of electrical power to new buildings, can cause power fluctuations in a local area.  That's why I use a UPS with my main system.   

[kpac]

That's why I use a UPS with my main system.

Yeah, I've seen those. How long do they keep the PC running for?

[soybean]

Well, the time may vary quite a bit, depending on the cost of the unit.  I just looked at a unit sold by newegg.com. It's this one: http://www.newegg.com/Product/Product.aspx?Item=N82E16842111038  The specs say: Full load runtime: 3.5 minutes (550VA); Half load runtime: 10 minutes (275VA).  That's not very long but, when properly setup with a computer, the computer will be properly shutdown before the battery runs out.  So, you don't need to worry about improper shutdown if you are not there when it happens.

[kpac]

Okay, thanks. A very useful component.

[westom]

I was in the habit of shutting off my computer during thunderstorms, and naturally, I had it running from a surge protector, so I thought I was safe.  What I had not realized at the time, was that my dial-up internet connection, which had a phone-line going straight from the wall jack to the computer, did not go through a surge protector, and was therefore an easy target, so to speak.  Sure enough, lightning struck a telephone pole, which sent a surge right through the phone line and killed the computer,

  So why did that surge ignore a surge protector on every phone line (installed free by the telco) to damage your modem?  It did not.  Your conclusions are a perfect example of why observation alone leads to erroneous conclusions.

  Surge entered on AC mains seeking earth ground.  That power strip protector simply shunted (shared, connected, distributed) the surge to all other wires.  Now a surge has a path to earth by bypassed protection in the power supply.  Through motherboard and dial-up modem to earth ground via a telco installed 'whole house' protector.

1) You had damage because you permitted a surge into the building. Once inside, that energy hunts for earth ground via appliances.

2) All appliances have effective surge protection.  But your protector simply bypassed protection in the computer’s power supply.

3) You assumed based only on observation.  How junk science is created.  You did not first learn fundamental principles which are also required to make a conclusion.  For example, you did not even know that all phone lines already have an earthed ‘whole house’ protector;  phone lines already have surge protection.

4) A protector located too close to appliances and too far from earth ground may even earth surges destructively through nearby appliances.  What does a protector do?  Divert surge energy to earth ground where it can cause no harm.  But your protector had no such earth connection.

5) You assumed the plug-in protector provides protection.  Even the manufacturer does not claim that protection.  Will it stop what three miles of sky could not.  Will it few joules absorb a surge that is hundreds of thousands of joules?  You assumed that.

Point 5 specifically answer the OPs question.

That protector did not provide protection, did what its manufacturer's spec claim, AND may have contributed to modem damage.