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Rad

Lightning strike!

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Ooh migawd! My home was struck by lightning! :-X AGAIN! The second time in less than one year. It fried my TV!! The last time it fried my TV and damaged the PC. But I'm not counting myself lucky this time :x

What's the matter with weather today?! Does my house have this "strike me" sign that I don't know about? :?:

Grrrrrrrr.........

Rad

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Rad,

There is usually (in the USA) a grounding rod or lightning rod attached to the side of a house or very near it. It is to guide static electricity and lightning along the rod, into the ground, away from a house, without harming it.

Check with a local building contractor, I'd expect your home has something similar. Perhaps that or something else needs improvement.

I hope the storms (and especially the next rainy / monsoon season) will be kinder to you and your neighbors!

Take care.

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There is usually (in the USA) a grounding rod or lightning rod attached to the side of a house or very near it. It is to guide static electricity and lightning along the rod, into the ground, away from a house, without harming it.

Actually, that won't work. The estimated power of a direct lightning strike can go well over 1,000,000 watts, with an unbelievable current. This is enough to physically jump over a conventional ground and still make contact.

In other words: there is no real guaranteed protection against a direct lightning strike. If it's a minor strike, yes, lightning rods and grounds can help, but not if 100% of the full force of the lightning hits a building or object. (I know this because I have some electrical engineering background, plus I grew up in Tampa, FL, otherwise known as "the lightning capital of North America.")

About all you can do to protect yourself and your equipment is to stay indoors and unplug any essential electronic gear from the AC outlets.

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There is usually (in the USA) a grounding rod or lightning rod attached to the side of a house or very near it. It is to guide static electricity and lightning along the rod, into the ground, away from a house, without harming it.

Actually, that won't work. The estimated power of a direct lightning strike can go well over 1,000,000 watts, with an unbelievable current. This is enough to physically jump over a conventional ground and still make contact.

In other words: there is no real guaranteed protection against a direct lightning strike. If it's a minor strike, yes, lightning rods and grounds can help, but not if 100% of the full force of the lightning hits a building or object. (I know this because I have some electrical engineering background, plus I grew up in Tampa, FL, otherwise known as "the lightning capital of North America.")

About all you can do to protect yourself and your equipment is to stay indoors and unplug any essential electronic gear from the AC outlets.

Er---- :cry: you're not making me feel better :D I'll have to unplugged all essential electric equipments then.

Cheers!

Rad

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You can spend the money to buy and install one of those triangular shaped radio towers. As long as it is higher than the house, it is a virtual certainty that it will take the strike. Just make sure there are plenty of grounding wires at the bottom of the tower.

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You can spend the money to buy and install one of those triangular shaped radio towers. As long as it is higher than the house, it is a virtual certainty that it will take the strike. Just make sure there are plenty of grounding wires at the bottom of the tower.

As many people find out the hard way even a $300 surge protector will NOT stop a direct lightning hit*. There is a specific device called a lightning arrester that CAN. However they aren't ever cheap. No such thing as a cheap lightning arrestor. (There are cheap ones to attach to your cable line and if you have an outside antenna, I highly recommend one -- they're about $80 and will protect ONE cable only.)

* Wibby took some Electrical Engineering courses and could bore you with technical reasons for this but won't except to say those little parts can't stand the voltage and temperature.

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As many people find out the hard way even a $300 surge protector will NOT stop a direct lightning hit*.

Haha, yeah. I remember thinking "Oh, no need to worry about lightning - my $20.00 extension cord has a built-in surge protector! Says so right on the box!"

One fried motherboard and power supply later, I started unplugging everything whenever storms roll through.

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Well, Blue's original suggestion was actually pretty good. A lightning rod won't help too much if it takes a direct hit, as Pecman pointed out but the idea of a grounded lightning rod is actually to handle the smaller voltages/currents (static electricity) that are constantly around us and that precede a real strike.

A major lightning strike happens in a fractiion of a second but it is preceded by a build up of difference in potential (emf) between the earth and the surrounding air. Dissipating that can make it less likely that potential will built up to such a level that lightning acually stikes.

Static electricity can appear in a variety of circumstances. I once happened to unplug my ham antenna during a snow storm and actually saw a two-inch spark jump to a radiator from the connector. And that was with no lightning in the area!

Trab's suggestion of a grounded ham radio tower will also work as it has the same effect and by it's larger diameter and could carry more current safely.

Most important is to make sure your house isn't the most attractive point for the strike... reducing the static charges in the air is a good way.

But frankly, if lightning strikes nearby power or telephone or tv/Internet cable it can take out your TV/Computer/Home Audio/Video equipment, no amount of home protection is gonna guarantee you are unscathed.

On that happy note........

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I lost my last trusty computer through a lightning strike on telephone equipment up the road. The surge appeared to have gone through the internal modem and fried the motherboard.

On the good news, that was a Pentium-Pro 180 with a 2GB hard disk and 32MB of RAM. The insurance company replaced it with what they considered to be an entry level computer - Celeron 1.8GHZ, 20GB hard disk and 256MB of RAM. I paid the excess ($100) and then paid a small amount more (about another $100) and got the hard disk and RAM upgraded before they shipped it to me.

I now have TWO surge protectors on the phone line, in addition to the one on the powerline. Yes, they aren't perfect, but they help (especially when you live at the end of the power line and supply has been known to become intermittent at times).

Graeme

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I don't know if it works to protect from lightning, but I run all my computer equipment (except the laser printer) through two UPS units. They continually cut in and out as we have small brownouts, surges, and outright failures. We've only had lightning in this area 2 or 3 times in 10 years, so I'm not overly concerned. I've had more trouble from viruses (virii?) and mechanical faults within the computers than from electrical deviations.

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A few problems... local construction sites sending spikes up and down the power lines and a general unstable power mains situation prompted me to buy an AVR Automatic Voltage Regulator about six months ago after I lost 3 (count 'em) PC power supplies. I did overkill and got a 3KW unit... lightning season started after that and while a major lightning storm fried my cable modem, and those of about 300 other folks, nothing got through the AVR and all MY equipment survived. Telco is great up here with shielded telephone lines... so my DSL and ISDN backups kept me online. Do I sound paranoid? Well I also bought a power generator at the same time, lest I miss broadcasting a newscast on OutQ! :cry:

An ounce of prevention.....

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Dude, you're doing the right thing. Getting a decent uninterruptible power supply is the cheapest insurance you can get for stuff like this. I have a 2KW APC box on my main computer in my office, plus a bigger one in my downstairs recording studio, and we have little APC battery backups on all the other computers in the house.

Most of those will only keep the things running for 10 minutes or so, but you figure that's more than enough to cover the little power bumps that happen from time-to-time. Still, when we got hit by the January 1994 Northridge earthquake, I was in my office at the time, working on my computer, on-line to the Net and listening to the radio, when the house started shaking. One minute later, after I picked myself up from off the ground, the only light in my entire house was from the few monitors backed up by UPS's! Without those, it would've been a lot harder to crawl out of the rubble.

BTW, if you're running a generator for your stuff, be sure to get a regulated output for it, and make sure the output voltage is "sine-wave clean." This is a lot better for audio and computer gear.

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