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Domestic Lightning Protection Systems, Bangkok?


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Anyone aware of companies installing domestic lightning protection systems at 'domestic' prices, all the big names are concentrating on commercial systems at 'commercial' prices (too many zeros).

I reckon we need six air terminals (lightning conductors) with three ground conductors and earth mats (I expect the contractor to do a survey of course).

My reason for asking? We had a direct hit yesterday afternoon, scared the willies out of the wife and blew 3 ridge tiles into next week, the structural damage was limited by our steel roof structure being very well connected to the re-bar all the way to the piles (it's a damn good earth already).

Thank heaven there was no fire!

Photos:

post-14979-0-68761500-1384424519_thumb.j post-14979-0-55929000-1384424738_thumb.j post-14979-0-96455400-1384424792_thumb.j

We were lucky and got away with no damage to the house wiring, quite a bit of technology was not so lucky:-

  1. Satellite LNB - replaced free by True (all three receivers survived)
  2. TOT WiNet router and POE adaptor - replaced free by TOT
  3. Linksys wireless router - replaced by a 2,500 Baht Trendnet unit (better spec)
  4. 2 of three UPS's gave their lives protecting PCs etc. - around 5,000 Baht each
  5. Half a dozen CFLs and all six of our electronic ballasted fluorescents died, not replaced them yet, HomePro trip tomorrow.

Roof was fixed for an amazing 2,280 Baht including materials (back home that would have been 2,280 Pounds).

All in all we got off lightly, next time we may not be so lucky.

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Just a hint, lightning loves "pointy things" the sharper the better. May not look authentic or pretty but round all the pointy things on your roof and above the roof.

Although nothing will protect agianst a direct strike, think about installing Lightning surge protectors on your electrical pannel, cheap and effective protection.

Also remember lightning rods are designed to "atract" lightning than shunt/send it to a safe place/ground.

Also look around your home, lightning will usually be attracted to "things" antennas, structures that are near and higher than you structure. Agian beaware of the pointy things.

Google "lightning zones risks" there are several good sites that will give you an idea of your risk of being hit.

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Removing or rounding the (pointy) teak barge boards is not an option. So we need something "pointier" to direct any strikes away from the structure.

We already have whole house surge arrestors (which now have new cartridges although, interestingly, the indicators did not show any triggering) and good quality (Belkin) plug-in protection at the technology, I have no doubt that much of our kit that didn't die was saved by these.

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I think my house is built on a lode stone or something. Over the past 15 years, I have had three very close lightning strikes, and one direct hit ( or perhaps I have angered the gods). I did a lot of research on lightning rods, etc. My personal conclusion is that lightning rods are basically decoration. For proper protection, lightning diffusers, as seen on radio transmission towers are needed. They are commercial products, and very expensive. I decided to stay with insurance coverage.

Sent from my iPad using Thaivisa Connect Thailand mobile app

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I live in Bangkok and around two years there was a direct strike on my neighbor's house which is right next door...only a few meters separate our houses on one boundary line. It occurred shortly after midnight during a bad, bad thunderstorm. It blew a hole in the very top of roof by blasting away approx a half dozen concrete shingles/tiles...it was of course raining hard which allowed rain to flow in for several hours before it stopped raining. They got the roof repaired the next day.



The wife and I were awake in bed when that lightning bolt hit...couldn't sleep with all the lightning & thunder going on...suddenly, a bright flash and deafening sound at the some millisecond in time. Since both light and sound were heard at the same instant (and pretty much caused our hearts to skip a few beats) I was worried it may have hit and damaged the house. Well, there was no visible signs it hit our house also, but it did smoke my ADSL modem, my router, my VOIP adapter, the power adapter for the fax machine, the power adapter for a cordless phone upstairs, and the power adapter for a cordless phone downstairs. Shortly after the strike I could tell something was wrong with some of mentioned devices because of the LEDs on them...and next morning I confirmed the damage. The lighting may have rode in on my phone lines and/or electric lines. After that I built and installed a 3 line mode whole house surge protector/suppressor on my main circuit box and installed lightning suppressors for the phone lines.



Knock on wood but I haven't had any lightning damage since and have went through some more heavy-duty thunderstorms with some lightning strikes being very close by. But I will be the first to admit, if a lightning strike occurs directly on your house/electric/phone service it's probably still going to do some electrical damage even with first rate surge protection. Preaching to the choir I know.


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I live in Bangkok and around two years there was a direct strike on my neighbor's house which is right next door...only a few meters separate our houses on one boundary line. It occurred shortly after midnight during a bad, bad thunderstorm. It blew a hole in the very top of roof by blasting away approx a half dozen concrete shingles/tiles...it was of course raining hard which allowed rain to flow in for several hours before it stopped raining. They got the roof repaired the next day.

The wife and I were awake in bed when that lightning bolt hit...couldn't sleep with all the lightning & thunder going on...suddenly, a bright flash and deafening sound at the some millisecond in time. Since both light and sound were heard at the same instant (and pretty much caused our hearts to skip a few beats) I was worried it may have hit and damaged the house. Well, there was no visible signs it hit our house also, but it did smoke my ADSL modem, my router, my VOIP adapter, the power adapter for the fax machine, the power adapter for a cordless phone upstairs, and the power adapter for a cordless phone downstairs. Shortly after the strike I could tell something was wrong with some of mentioned devices because of the LEDs on them...and next morning I confirmed the damage. The lighting may have rode in on my phone lines and/or electric lines. After that I built and installed a 3 line mode whole house surge protector/suppressor on my main circuit box and installed lightning suppressors for the phone lines.

Knock on wood but I haven't had any lightning damage since and have went through some more heavy-duty thunderstorms with some lightning strikes being very close by. But I will be the first to admit, if a lightning strike occurs directly on your house/electric/phone service it's probably still going to do some electrical damage even with first rate surge protection. Preaching to the choir I know.

Err... unplug when it starts getting bad?

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  • 3 months later...

A quick bump of this to update.

The 'lightning man' came yesterday, apparently a local chap who does these things as part of his business, of course I wasn't home at the time.

He left a fag-packet sketch which I've used to create a Visio drawing (see below) and will return today (maybe) with a quote.

post-14979-0-23520400-1393295223_thumb.j

I'm no expert on lightning protection systems, and information on the web is sketchy regarding steel roof structures like ours, plenty on wooden roof construction.

Any and all input on the following queries (and any other thoughts) appreciated:-

  1. Can I use the roof structure as part of the down-conductor so we don't have visible wires?
  2. Should all the down-conductors be bonded together?
  3. Should the lightning system be bonded to the electrical ground?

I know No.3 will be controversial as it seems to depend where in the world you are located whether you bond or not.

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To answer some of your questions:

1. The lightning protection system should be kept separate and insulated from your roof structure.

2. The lightning protection system is joined together on the roof, air terminals should be as close to the end of ridge with 1 foot maximum from the end. With the air terminal too far from the roof end the lightning strike will likely strike your roof end tiles and not the air terminal. Depending on roof length more air terminals may be required at equal spacings along the roof ridge.

The down conductor, usually bare copper 35mm2 should be installed at opposite diagonal ends of the house keeping the run as straight as possible with no sharp bends and terminated to their own grounding rods. Installing the down conductor in a conduit is ok.

3. Your lightning system should be bonded to your main earth terminal, if not you will have a potential difference between the two earths and during a lightning strike potentially high voltages will appear at your consumer side of your electrical installation. It is paramount that total house surge protection devices are installed upstream of any circuits.

A test point should be installed on the down conductor to measure and ensure integrity of your lightning protection system. From this point is where you can take a bonding conductor to your main earth terminal.post-124565-13934866897613_thumb.jpg the attached picture shows the test box I have installed.

The conductor on the roof should be insulated from the structure, see attached picture showing electrical insulators that I have used.post-124565-1393486843107_thumb.jpg

PFor connections to the ground rod, cad weld type connections should be used, in Thailand these are called "one time" connections and are readily available. Ensure ground rods are inside an earth pit.

All metallic structures within your house/roof has to be bonded to your main earth terminal to avoid potential differences and flash over during a lightning strike.

For further information have a look on the Furse website which is a company that specializes in earthing systems.

Sent from my iPad using Thaivisa Connect Thailand

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