Turn Off Computer While Thundering ?

[miodo2009]

Is it a good idea to turn off a computer when it's thundering ?

[sbk]

I do, unplug too. But then we've had our place hit by lightning and had our computer fried so I am now very wary.

[PoorSucker]

You should be OK if you have an UPS.

Unplug your modem though.

The power surge goes through the telephone line.

[sbk]

UPS won't stop a lightning strike but yes, unplug the phone line out of the modem too.

[Daewoo]

You can buy "powerboards" (multiple power outlets) that have surge protection for both the mains power, and also for your wired landline...

simply turning off the computer or modem is no guarantee against damage... I remember talking to a Canon technician who said he could track a storms path across Sydney by his call-outs to fix Fax machines...

Daewoo

[garyh]

You can buy "powerboards" (multiple power outlets) that have surge protection for both the mains power, and also for your wired landline...

simply turning off the computer or modem is no guarantee against damage... I remember talking to a Canon technician who said he could track a storms path across Sydney by his call-outs to fix Fax machines...

Daewoo

Those power boards are no guarantee either.

[astral]

Unplug the computer and the phone line.

This is what happened to my neighbours electric meter after a direct strike on the pole.

[garyh]

Unplug the computer and the phone line.

This is what happened to my neighbours electric meter after a direct strike on the pole.

Bet you had to change tour under wear after that happened.

[astral]

Bet you had to change your under wear after that happened.

Not quite, but is the only time I have ever used a fire extinquisher in anger.......

[welo]

I remember a discussion on this very message board with the conclusion that nothing (surge protector, outlet off switch) will protect the computer when the house is directly 'hit' by a lightning strike other than completely disconnecting from the power source. Even then the energy might travel through the house/ground near the computer and damage it.

But a surge protector might protect against a lightning strike in the neighborhood that is inducing a surge into the grid.

I'm just doing the parrot here repeating what I've heard, so others, please, do correct me!

[garyh]

I remember a discussion on this very message board with the conclusion that nothing (surge protector, outlet off switch) will protect the computer when the house is directly 'hit' by a lightning strike other than completely disconnecting from the power source. Even then the energy might travel through the house/ground near the computer and damage it.

But a surge protector might protect against a lightning strike in the neighborhood that is inducing a surge into the grid.

I'm just doing the parrot here repeating what I've heard, so others, please, do correct me!

Surge protectors vary in quality, they also need an earth and most thai power points don't have an earth. Unplugged is far safer than relying on the surge protector.

[dave_boo]

I agree that unplugging is the best option.

Another thing that I haven't seen in LOS, and is common in my homeland, are lighting rods. Basically really big metal poles that go up in the air and are grounded out to attract the lighting down the path you decide rather than it wreaking havoc on your investments....

[BB1950]

Unplug the computer and the phone line.

This is what happened to my neighbours electric meter after a direct strike on the pole.

Unplug??? Easier said then done. Sometimes you don't have the time.

I had a very similar incident with a direct strike. In my case there was nothing left of the meter box or meter. Sparks shot out from the wires like a roman candle for a distance of 10 meters till the power company managed to find the place and turn of the grid (over an hour later). The lightning also hit struck the TV antenna of the neighbors house and his TV literally exploded.

I actually was using the computer at the time. It struck without any warning! Like a shot in the dark, very bright and disorienting, and the sound it was deafening loud! I have a UPS which also has phone line protection and the house is well grounded. I can say in this case the UPS saved my computer in a fraction of a second the computer was turned off and the monitor flashed. I did lose the data I was working on but the computer was saved.

However, I can't say the same for 1 external CD R/W, 1 TV, 1 Satellite Receiver with LNA, and 1 DVD player which all had to go to the shop for repairs.

Also 3 fluorescent light fixtures literally exploded about and 25 light bulbs blew out (all which were on at the time). Also sparks shot out from the wall plugs just like what you have seen in the movies.

I'm sitting in the dark, trying to figure out what just happened. About 20 minutes later, I see the lights go on at the neighbors but all my lights are still out... I'm walking around the house with a flashlight trying to assess the situation. Then I hear this loud humming sound outside. I open the door to check what the heck the noise is and to my surprise, I see the flames/sparks shooting from the meter box.

I quickly run back in the house and kill all the mains. I go back out to assess the situation. The flames are shooting across the road, so I can't leave by vehicle to notify anyone. The flames are about to set the tree on fire outside my neighbors bedroom with her screaming "what you do" and crying.

We try calling the police and fire services and were getting nowhere as we live in the boonies. We just had to sit and wait it out, hoping someone would notice. Thankfully, a young boy did, and directed the emergency crews in the right direction.

Something I will never forget.

The point is: Yes, unplugging expensive electronic equipment is the best suggestion. But sometimes you don't have the opportunity or time. In this case the UPS did its job well and protected my computer, so that also works. But as mentioned before by others YOU NEED A PROPER EARTH for it to work! I can't express the importance of that any better.

By the way, since strike was so unannounced and disorienting, it took me a couple days to figure out just what exactly happened. When you are at ground zero, you have no external perspective.You just witness all these strange and bizarre things happening around you. It happened in a flash of an instant, but it definitively seemed much longer.

[astral]

I do agree on the Earth.

When I had my house rewired I insisted on 3 pin sockets at all outlets,

despite the electrician's opinion, "no need".

You can check the earth, by connecting a light bulb between live and earth on a plug,

if it lights the earth connection is good.

[garyh]

I would insist also on earth leakage protection which if you tried your test would trip out the safety switch, much better than having someone dead.

[Mosha]

To the OP, it depends how loud. Seriously if the gap between flash and bang hits single figures when counting. I turn off.

Edited July 13, 2010 by Mosha

[astral]

I would insist also on earth leakage protection which if you tried your test would trip out the safety switch, much better than having someone dead.

That was an integral part of the new distribution box that the electrician fitted.

Though they can be added to any existing system for greater safety.

[garyh]

I would insist also on earth leakage protection which if you tried your test would trip out the safety switch, much better than having someone dead.

That was an integral part of the new distribution box that the electrician fitted.

Though they can be added to any existing system for greater safety.

If you can connect a light between active and earth and get the light to stay on your safety switch is not working.

[elkangorito]

If you want proper info on Surge Protection Devices (SPD's), try the DIY section.

[loong]

I had a direct hit on the antenna for my CDMA modem

Modem and computer totally fried

Had to get a new modem and computer (and underwear!)

Unplug modem and disconnect your computer from the mains.

[garyh]

I had a direct hit on the antenna for my CDMA modem

Modem and computer totally fried

Had to get a new modem and computer (and underwear!)

Unplug modem and disconnect your computer from the mains.

I disconnect all wires from outside to the computer, tv, fridge, washing machine, dishwasher, etc, that includes, antennas, phone lines and power cords. Those who think they are safe by just turning off the power switch should have a good relationship with Buddha.

[T_Dog]

Unplug the computer and the phone line.

This is what happened to my neighbours electric meter after a direct strike on the pole.

Astral, Thanks for posting that photo. Very impressive. I used to analyze lightning damage at an avionics company so pics like that are very interesting to me. You can never predict lightning behavior, but disconnecting everything is good practice.

[welo]

I have a UPS which also has phone line protection and the house is well grounded. I can say in this case the UPS saved my computer in a fraction of a second the computer was turned off and the monitor flashed.

That's valuable information! From other comments on this forum I assumed that a UPS would not save any equipment with a lightning strike so close.

I guess that a direct lightning strike to the house (TV antenna or mobile phone antenna) would still be 'too much' for a UPS to handle though.

welo

[elkangorito]

A Primary (direct) strike will, on most occasions, cause damage.

Secondary strikes can generally be controlled if appropriate protection is used. Appropriate protection is a device that has a fault capacity of between 25kA & 50kA (25 000 amps & 50 000 amps) @ an interval of between 8 to 20 micro seconds. This device is normally connected to your Distribution Board (consumer unit).

These 'secondary strike' devices are available everywhere but must be installed by someone who knows how to do this properly.

UPS's are not supposed to provide any protection against lightning. They may provide protection against voltage surges, depending upon the type of UPS used.

Edited July 16, 2010 by elkangorito

[Orion76]

About a year ago my building got hit by lightning.

I had a Leonics UPS with a surge protector. Result:

UPS: dead

Epson laser printer: dead

Belkin adsl router: dead

Intel Mac Pro: dead

I ended up getting the printer repaired on warranty, the Mac warranty was expired so it was 40,000bht to replace the motherboard. Router and UPS went in the trash.

Worst of all the motherboard was not in stock so I was without my work station for several weeks.

I purchased a large APC UPS, hoping it will protect me better, but whenever there is thunder I shut down my computer and unplug to be safe.

[welo]

Thanks, elkangorito, for the clarification!

Orion, I guess you cannot blame a UPS with surge protector for failing to protect equipment in case of a primary strike. A lightning strike is not a 'surge' in the network but a massive event. Of course there are UPS devices of different quality, some doing what they are supposed to do, others don't.