Hardware

Burned computer modem illustrates lightning danger

Photos show damaged caused when lightning strikes an internal computer modem. Reminds us to disconnect our PCs during storms.

When lightning strikes a computer, charred metal, melted plastic, and burned circuits are the results. This computer's internal modem was hit with a power surge during a storm. The computer was protected by a surge protector but it did not have modem outlets. And, despite the rise in wireless home networks, Ethernet and modem cables are still a source of danger for computers. Click the image for the full gallery.

Photo by Brad Rowden

This machine's owner brought it to IT Systems Administrator Brad Rowden--who took several photos. According to Rowden "most of the components inside of the machine were a mess."

"The case might have been salvageable with some good cleaning," Rowden told me, "but everything in there stunk terribly."

Miraculously, the machine's hard drive was undamaged and Rowden was able to retrieve all the customer's data. Despite this silver lining, I encourage you to show this gallery to your customers. If they don't take lightning seriously now, these photos might change their mind.

About

Bill Detwiler is Managing Editor of TechRepublic and Tech Pro Research and the host of Cracking Open, CNET and TechRepublic's popular online show. Prior to joining TechRepublic in 2000, Bill was an IT manager, database administrator, and desktop supp...

55 comments
mckinnej
mckinnej

Thunderstorms are a daily event here in the summer. If you unplugged for every one of those you would be unplugged more often than not. Yes, I'm exaggerating, but not much. I really prepare for these you would have to unplug every day before leaving for work. On a more personal level, I arrived home yesterday to find my server shut down. Apparently the power went off during yesterday's storm and the UPS died. I powered it back up but now the mouse doesn't work. :( Mouse works fine on other machine, so I'm worried it got the motherboard. Other USB devices seem to work though, but haven't tested everything. Sigh...that's life in the lightning capital of the U.S.

steve6375
steve6375

I work for a computer OEM and we have seen many examples like this (but not quite as bad). From experience I can say that even a near lightning strike can cause enough EM discharge to induce a large voltage into telephone cables (or long RS232 landline cables or enet cables between buildings) to fry the electronics/modem card and even the mainboard. If you have a telephone modem, always unplug the telephone cable during a thunder storm. If you are using RS232 landlines or similar long cables even if underground - always use an optical isolator. So if you find that your PC does not boot after a thunderstorm, try removing the modem card first before you throw the PC away!

Regulus
Regulus

Yes, - Happened to me also, but not so severely. Being in South Florida, during the 'rainy season' means extremely violent electrical activity almost daily. That also means that you occasionally become lax and frequently you're just not around. YEs, everything (all cables & wiring)goes through a surge protector/UPS, but I suspect that there is only so much that they can handle. Remember also, there is such a thing as a electro magnetic pulse (forget the real term) which can compromise electronics that are not even plugged in. This is probably among the reasons that many of our defense systems are deep underground.

DadsPad
DadsPad

I use UPS's on all expensive electronics at my place. Not just pc's, but TV systems. My brand of preference is APC Smart UPS, I can find them locally discounted for $129 for 1200 - 1400V. Isolated pc/laptops are protected with a less powerful UPS. A UPS uses battery(s) that charge up to run your pc or other procuct, this is better protection to isolate the outside electricity from the product using it. With a good UPS, a lightning strike through the protected wire will burn the UPS and not the pc or other electrical product. Most new UPS have protections for line modems and network cables. But I have not ever tested this.

jeslurkin
jeslurkin

...work if its outlet is not grounded. I have experience with an old house wherein the boxes were not bonded, and some were not grounded. Most of the old two-prong outlets had been replaced with three-prong without checking ground integrity.

freaknout
freaknout

Looks like two Eisa slots, thats odd

freaknout
freaknout

Phone lines don't have surge suppression nor grounding No wonder

hcgriffith
hcgriffith

After reading more of the posts relating others' experiences I thought of two points that may help. One of the commenters mentioned a cooked drive card. I been able to recover 15-20 drives by replacing the interface card with one from an identical hard drive, but not many people will have access to the number of surplus drives that I luckily have. In one instance a Seagate 40GB drive could not be seen by the BIOS and I tried a card from the same range, but of 60GB capacity and it worked! When I get a machine with a bad physical drive (click,click,click), I save the card in a static bag with detailed info about the drive and have had pretty good recovery rates. Having said that, I have probably had 15-20 failures where the drive is physically trashed and the replacement card can't help. As to UPS units, the best protection I have found are the ones that constantly provide pure sine wave output generated by the unit whether on AC or battery, thereby absorbing any surges at the UPS' input. One of the better manufacturers calls their range of this type of UPS the Smart UPS. I have no financial connection or interest in this company.

mike_johns
mike_johns

I once had a customer bring in his PC for repair after a lightning strike, but the strange part was that after burning up the modem, the hard drive failed and looking at the reporting tools about the HD, it looked like the electricity arc'ed across the plates of the drive.

Rodo1
Rodo1

...in Failure Analysis and I'd get back disc drives that looked like this occasionally. It wasn't lightning, but some "Rocket Scientist" installing a drive and forcing the power connector in backwards. I've lucked out I guess because we get some pretty heavy duty lightning storms here in Colorado. May have to re-think my strategy!

mwclarke1
mwclarke1

I had a similar issue once, but with my home wired network. I usually have everything that has a power, phone, network, cable/TV, etc protected, my main components and whatever I can afford goes behind a UPS. I have been involved with lightning studies on telco and network infrastructure, think I would know better. But one time I was moving things around, put a temporary desk in the living room on the outside wall and never got around hooking up a network hub there onto the UPS, plugged directly into the wall since needed an extension cord and did not take time to do that right then. well it happened, took a direct hit to a tree in the backyard, flashed over to the chain link fence, burned right through a extension cord had outside, laying over the fence (was running power tools the day before), forgot and left plugged into an outside outlet that unknowingly was a shared circuit with the living room outlet that my hub was plugged into. The extension cord was burned in two, outlet fried, HUB fried, then went from the HUB to every device plugged into that HUB, including two other hubs/switches and devices plugged into those. For some computers that had the PCI network cards, only had to replace those, other computers I had to replace mother boards. HUB/switches were totally gone, and both my jet direct devices. Several lessons learned, the expensive way. BTW: I had a TV once hooked to one of those cheap power strips that claimed to have surge protection, fried it and the TV. While working in Electronics and the Computer field for almost 30-years now, I have looked at many surge protection devices, taken apart after lighting has hit, there is a difference. The cheap ones are worthless. If really want to protect something, going to pay 50-60 or more for the good ones, cheaper does not work. It is just better to protect the more important devices with a UPS, just provides better protection being more isolated, against brownouts and surges.

hcgriffith
hcgriffith

When lightning strikes near a telephone line, (and it does not have to actually hit the telco line) the wire acts like the secondary of a transformer, generating a voltage by inductance. Ferrite cores, included with many modems, can reduce this surge by acting like a reverse transformer, folding the surge back on itself in a way that uses the surge's own force to counteract the voltage/current pulse. Oddly enough, simply tying knots in the wire from the wall socket to the modem can provide much the same protection. (Electronics geeks, remember the 'Left hand rule', the field generated by the surge cuts across the twisted knot and generates a current in the opposite direction, partially cancelling the surge, the more knots the better) A friend who could not remember to unplug used to lose a modem every summer until I had him use the knot strategy. He was hit again afterward but never lost the modem. A good case for using external modems, much less chance of feed through, and if the modem/PC interface is fiber, no chance, as fiber is a near perfect insulator.

jrfoleyjr
jrfoleyjr

If you place the computer (and power) inside a faraday cage and allow it to communicate to the outside world only via optical cable, you may be safe from lightning.

coolmark82
coolmark82

A few months ago when I had a bad storm in the area, The surge protector didn't protect anything. Instead, it just let the havoc of lighting tear through the network of modems, routers, and switches and racks. Good thing most of my computers are wireless now. Wireless is probably a safer alternative rather than risking a charred computer. i learned that very well.

oldbaritone
oldbaritone

I actually put a pair of fiber media converters with a 5-foot fiber between them, in between the cable modem and the router. I took a hit similar to this one a few years ago, with similar results. Now, my phone line is VOIP, so the ground is internal and behind the fiber link. The modem is downstairs by the cable service entrance, and the fiber connects the cable modem to the router. It was a cheap solution; I bought the pair of converters with the cable for less than $50. I also always suggest fiber to customers who want to run connections between buildings. With fiber, there are no problems with ground-loops between buildings, and no worries about lightning or ESD, because fiber is non-conductive. With a pair of media converters, they can run everything on Cat 5/6 inside the building. Only the link is on fiber, so they're working with equipment they're familiar with, and don't need to go to the expense of putting fiber ports in the server, switch or router - unless they want to.

Neon Samurai
Neon Samurai

Back in the day, it was getting Dos and *nix to play nice with the hardware address and interrupt. Stick an external modem on your port and your golden. Limiting the blowout to an external box rather than collateral damage inside the case is a pretty good reason too though based on the pictures. Of course, any powerbar/surgeprotector worth buying these days will have a phone cable protector and probably an RJ45 also.

abiemann
abiemann

I have a fiber-optic connection to my ISP and I haven't bothered to disconnect anything during a storm. Also, electric cables throughout the neighborhood are buried. The only time I disconnect my expensive electronics is after complete power failure.

dave1ee
dave1ee

The very reason that I highly reccommend to all of my customers to do what I have done in my shop, and my home as well. That is to have a "real surge suppresor" with cable and modem in/out attachments rated in jewels of power (not just a powerbar) or on some of my high priced Computers/electronics a UPS/Surge Suppressor. I live in SE Ohio and we get a lots of severe thunderstorms and the ones I use have saved us many times.

Slayer_
Slayer_

Wouldn't those devices detonate and effectively stop the flow of electricity?

santeewelding
santeewelding

To see if, serendipitously, the surge repurposed everything, like, creating now a desktop linear accelerator?

JohnMcGrew
JohnMcGrew

...I'll show them these. I've never experienced anything quite like this, but I have had hardware zapped by storms before. Years ago, I had a client who had almost every network card in the office fried. A light post out in the parking lot took a direct hit. There was no direct power surge in the building. However, the network cabling through the office acted as a giant antenna that absorbed quite a bit of the EMP, which was then sent through the network cards. Fortunately, only the network cards were damaged and after their replacement all was back to normal.

Chug
Chug

About 17 or 18 years ago, at my previous job, we had a coaxial Ethernet network, where computers were chained on the same cable. We had a lighting hit in the office one night that took out a repeater, hub, and every PC on that hub. At least in that case it only took out the NIC in the PC's and not the whole PC, so we just had to replace the NIC.

.Martin.
.Martin.

storms sometimes pass through Melbourne so fast, that I wouldn't have time to turn of my computer. In saying that, the only way that a surge could get into the network, is through a coax cable connected to the modem. I also have to say, I like the 200% no response :p

Bill Detwiler
Bill Detwiler

When lightning strikes a computer, charred metal, melted plastic, and burned circuits are the results. This computer?s internal modem was hit with a power surge during a storm. Do you always disconnect your computer's power/modem/network cables during a storm? Check out the photos and take the poll: http://blogs.techrepublic.com.com/itdojo/?p=1835

Neon Samurai
Neon Samurai

I was finally able to add a UPS to my system a while back and I still giggle a little when a power flicker hits, the lights go off and on and not even a hickup with the machine in-front of me. After the first power flicker that didn't take out my desktop, I started looking around the house at everything else I could add a UBS behind.

wdewey@cityofsalem.net
wdewey@cityofsalem.net

There are cheap electrical outlet checkers that will tell you if things are wired properly. Bill

jeslurkin
jeslurkin

No expert, tho' I think that they're PCI that have been blackened by the heat.

wdewey@cityofsalem.net
wdewey@cityofsalem.net

Newer surge protectors usually will have coax and telephone connectors for insulating these devices. Bill

blotto5
blotto5

i luckily never had this happen to me, but i did used to think i was safe behind a ups for power surges and whatnot. i never thought a power surge could come thru ethernet and fry my computer that way. o well i guess i should thank techrepublic for this knowledge and go try to protect my $2000 computer better.

wdewey@cityofsalem.net
wdewey@cityofsalem.net

Most fiber optic cable that I have seen once it is in the house doesn't have anything that will conduct electricity in it. Bill

trog7
trog7

about 5 years back - before "broadband" was available in my country town, I heard a storm approaching and was in the process of closing down my laptop computer, when suddenly there was a huge flash outside and one of the loudest kabooms you'll ever hear, and at the same time a big POP from inside the laptop ... the modem chip had exploded. A neighbor who had been outside at the time reckons the lightning bolt hit the ground just about a hundred yards down the road , and there are buried phone cables - not exactly close to the spot, about 40 feet from the impact, but close enough to send a huge jolt through the phone cable. Luckily that time only the modem chip blew up. So, even IF the cables are underground, don't think that will stop lightning from causing damage. As long as there are some sort of metals near to where the lightning hits, this will carry electricity. Okay, optical fiber as long as it isn't in a shielded cable should be non conducting...

wdewey@cityofsalem.net
wdewey@cityofsalem.net

Do you have any on Ethernet connections? I have looked at some Ethernet surge suppressors but I didn't know if they may cause data errors on the line. Bill

trog7
trog7

I have heard of 1000 Amp contactors vaporizing in lift wells during thunderstorms A lightning bolt travels miles through the air, what is a circuit going to do if the appliance is still plugged in ...??? A friend just a couple of years ago had every power point and appliance in his house evaporate when a power pole opposite his property was struck --- even all the cables were destroyed , just lucky the whole lot didn't catch fire !

SerrJ215
SerrJ215

A direct strike could take out surge protectors and UPS, daisychained down the length of a football field. Also this was an old fashioned modem. Witch is an old fashoned piece of silvercord 2 pair wire, connected to a wall outlet up to the phone lines, right to the machine. No hubs no switches, there are a few surge, and UPS that have connections for RJ11 connectors you can loop the connection through but this wasen't the case.

oldbaritone
oldbaritone

Shutting down alone is not enough. Unless the equipment is unplugged from power, phone and network, it's still susceptible.

Dave Pusey
Dave Pusey

Those photos just look like it's very dusty to me. First thing I would do is get use the compressed air.

SmartAceW0LF
SmartAceW0LF

That before making a final diagnosis of a fried motherboard, always pull the modem and try again. Yes, a good practice for any/all accessory cards I know. That said, as often as not, the culprit is a modem that was fried during a storm, even after the owner unplugged the box for fear of the storm damage. Same often holds true for NICs. Just one of the things I learned early on not to overlook in situations that for all practical purposes would otherwise appear to be fried motherboard.

hmmmph
hmmmph

I agree with you Neon. I am a telecommuter and have a nice lan setup. The first item my hubby did for lan was purchase a UPS that we could connect our modem to. We had an unfortunate situation that happened to us years ago with an ungrounded wire and our Modem. Never again. So now...when the power goes out...it might be dark in the house, but we still have internet access and since i'm working with a laptop - battery power that will allow me to get an email out to my boss and shut down the computers safely. I love my UPS :)

The 'G-Man.'
The 'G-Man.'

Everything has an Earth via a real Pin on the plug to socket.

santeewelding
santeewelding

Whether misspelled or not, we probably ought to start thinking of them that way, given how expensive they're getting to be.

Slayer_
Slayer_

If it won't block a surge?

JohnMcGrew
JohnMcGrew

But it's practically impossible (and tedious) to be 100% safe.

AnsuGisalas
AnsuGisalas

Not dust. Compressed air is no use. Soap and water might get it off, but we all know how useful that is on circuitry.

Glenn from Iowa
Glenn from Iowa

But the beauty of most good surge suppressors is they have insurance tied to them that will replace your equipment if it is damaged. Had a surge suppressor get fried several years ago - fortunately the computer wasn't damaged - but the company swapped out the surge suppressor with no problem. I haven't had the opportunity to use it, but most good surge suppressors I've seen recently have $10,000+ insurance for connected equipment damaged by a power event. And I hope this isn't offensive, but... no birth control method (except abstinence) is 100% percent effective either, but there's still a good reason for people to use them. :-)

wdewey@cityofsalem.net
wdewey@cityofsalem.net

They are larger cables tied directly to ground. They are completely dedicated so there is no need to redirect energy. I don't know that they will absorb 100% of a direct strike, but they re-route much of it so there is less damage to repair. Surge protectors are providing a flow of energy so they have to be able to redirect anything over a certain amount which is where their threshold comes in. Enough energy will jump through small gaps and continue down the line (or large gaps such as the distance between a cloud and the ground). Bill

SmartAceW0LF
SmartAceW0LF

That is in providing the means to disconnect everything plugged into it with one convenient plug. After all, rarely is the "surge" the death knell for electronics -lightning excluded of course- It is the ensuing "lack" of voltage or brownout that follows the surge that usually deals the death blow.

AnsuGisalas
AnsuGisalas

Apparently they cost like ten thousand, and they're so-so in reliability. What it is; a big, no, huge metal bar mounted close to the main fuse box. Connected to a bloody pike on the roof, and connected to a bloody pike down into the ground. KISS.

freaknout
freaknout

how in the world those lightning protection rods and cables on roof tops actually work.

oldbaritone
oldbaritone

I've been there, too. The surge protector will protect your equipment from transients that come down the line from a nearby hit. They just CANNOT protect your equipment from a direct hit. I know. I had a hit several years ago. I had a light in my back yard, on a tree. The tree took a direct hit. The 12-gauge extension cord to the light was literally blown into a dozen pieces. The surge came back into the house and fried the computer, two TVs, several clocks and radios, and a bunch of light bulbs. It's hard to imagine the amount of energy in a lightning bolt. I couldn't believe there was that much power. There is. So, the surge protector IS a GREAT help to protect you from the hit on your neighbor, or the hit on the power line. In that case, the surge comes along the wires, through transformers, and loses energy along the way. They're WELL WORTHWHILE, but there's only so much they can do. If you read the specifications for the protector, it will tell you how much energy it can absorb. But when lightning hits you directly, it's literally MILLIONS of volts and THOUSANDS of amps. There's no way a little box can absorb and dissipate that much energy. And the end result is pictured in the article.

AnsuGisalas
AnsuGisalas

...has a lightning bolt with your ethernet cable's name on it!

jeslurkin
jeslurkin

Thanks for the link to the other article/discussion. I have seen recommendations to use the dishwasher without soap or high-heat dry. Only problem with 'my' dishwasher (besides the fact that it is used to _actually_ wash dishes) is that it dispenses a rinsing agent that can not be stopped. OTOH, if something is so dirty it will be trashed anyway,... why not try?

AnsuGisalas
AnsuGisalas

...does no favor to electronics. It's the short end of a long stick.

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