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lightning protection

PostPosted: Wed Jul 26, 2006 2:55 pm
by jonas
having read jopets unfortunate incident... how can we protect our precious gear from a thunderstorm?

is it enough that the equipment is turned off? should we unplug all our equipment from the mains? does it mean then that we shouldnt listen to music when there's a thunderstorm?

PostPosted: Wed Jul 26, 2006 3:06 pm
by rascal101
Lightning rod.

PostPosted: Wed Jul 26, 2006 3:34 pm
by Jon Agner
rascal101 wrote:Lightning rod.


True, but the lightning rod should be properly grounded as well. useless 'yan pag walang ground rod or the ground rod is not properly installed/mounted :wink:

Now, as far as thunderstorms are concerned, there are places that are susceptible to lightning strikes. If you're living in a high-rise condominium, make sure that the building is properly grounded and there's adequate lightning protection, since lightning looks for the shortest path possible.

Houses situated near large open areas (parks, playgrounds and open fields) are also susceptible to lightning strikes as well. So make sure that your equipment is adequately protected from lightning strikes. Houses with elevated tanks and antenna towers are also highly susceptible, so if you have these, make sure that the tower posts are properly grounded.

Isolation transformers may also be used as an added protection for your audio equipment. If I recall, Prof. JM during his lecture on Tubes101, drew a simple configuration for an isolation transformer with grounding leads on the primary. The ground leads should be connected to an earth ground (puede sa PLDT ground)

Hope this helps.

Cheers.

PostPosted: Wed Jul 26, 2006 3:46 pm
by aye
sir, pwede surge absorber such as Metal Oxide Varistor (MOV) or gas arrester.

PostPosted: Wed Jul 26, 2006 4:33 pm
by noctilux
isolation transformer, MOV's, TRUE ground wiring, and master disconnect switch or breaker close to equipment. When not in use, disconnect. The arcing of a lightning strike is known to jump through switches.

Isolation transformer: much ballyhoo against the use of this due to "current limitations" but I use a 5kVA trannie. I think this is sufficient for my load. This however should be with a connection to a reliable ground to shunt all the noise as well as surges. Lightning strikes are essentially DC and will not go through an isolation transformer. This was discussed previously in a topic closely related to surges.

MOV's: this should clamp overvoltages in the kilo-region instantaneously. Again lambasted for the apparent degrading sonic effects. I would use 3 of these, line to line and 1 each for line to ground. If it protects my gear, I would decide to give away 5% of my sound quality if any. I myself have not personally heard a sonic disadvantage to using MOV's. The problem however is you do not know if it's still working. Most of the time though, it blows like a firecracker when subjected to longer term surges or something as powerful as a kilovolt lightning strike

Industrial grade TVSS: or Transient Voltage Surge Suppressors connected parallel to your circuit. Available with a 45-60 day leadtime. You can connect this at the circuit breaker right after the service entrance of the house. Manufacturers: Liebert, MGE

Cheapest: Unplug

Remember, our computers are prone to lightning strikes not from the pwerline but from the phone line. Same with TV's from the cable line. Lightning rods are efficient if you have it in the highest portion of the area but is not a guarantee that your house won't be hit (I saw this one in Discovery Channel). Though you may get hit, you may get hit only once, as lightning never strikes the same place twice, daw... :twisted: :twisted:

PostPosted: Wed Jul 26, 2006 8:20 pm
by ihatejazz
For God's sake, pull out the plugs!!!
save the music for another day.
shit happens and don't be the unlucky one 8)

PostPosted: Fri Jul 28, 2006 8:49 am
by rascal101
It isn't fun to listen to music during thunderstorms anyway.

PostPosted: Fri Jul 28, 2006 9:25 am
by fld
its always safe to unplug the gears when lightning strikes. It aint worth the risk of gears damaged during that time....

PostPosted: Tue Aug 22, 2006 6:06 pm
by Octaver
fld wrote:its always safe to unplug the gears when lightning strikes. It aint worth the risk of gears damaged during that time....


This is the real SAFE Action especially for your expensive gears. There is no guarantee for 100% safe when lightning strikes lightning rods are just to prevent further damage but still need to unplug your electrical equipment during thunderstorm.

Imagine a Gap on your spark plug requires 10,000 - 30,000 Volts in order to jump (Arc) electricity in the air gap, how much more with this?


Image

PostPosted: Fri Sep 08, 2006 4:02 pm
by [L]es
For God's sake, pull out the plugs!!!
save the music for another day.
shit happens and don't be the unlucky one


how close is close ? what i do now is as soon as i hear thunder i unplug everything. too paranoid ? or just fine ?[/quote]

PostPosted: Fri Sep 08, 2006 4:06 pm
by ihatejazz
[L]es wrote:
For God's sake, pull out the plugs!!!
save the music for another day.
shit happens and don't be the unlucky one


how close is close ? what i do now is as soon as i hear thunder i unplug everything. too paranoid ? or just fine ?
[/quote]

Better safe than sorry :wink:

PostPosted: Fri Sep 08, 2006 4:08 pm
by [L]es
sabagay. and for that i delegate listening task to my el cheapo 1.3k headphones. but for what it's worth ? sounds pretty good a :D

PostPosted: Sat Sep 09, 2006 12:03 am
by JackD201
ihatejazz wrote:For God's sake, pull out the plugs!!!
save the music for another day.
shit happens and don't be the unlucky one 8)


Don't use a phone with a cord either!

Don't you watch CS!? :lol:

PostPosted: Sat Sep 09, 2006 12:14 am
by [L]es
CS ?

PostPosted: Sat Sep 09, 2006 2:53 am
by amandarae
Octaver wrote:
fld wrote:its always safe to unplug the gears when lightning strikes. It aint worth the risk of gears damaged during that time....


This is the real SAFE Action especially for your expensive gears. There is no guarantee for 100% safe when lightning strikes lightning rods are just to prevent further damage but still need to unplug your electrical equipment during thunderstorm.

Imagine a Gap on your spark plug requires 10,000 - 30,000 Volts in order to jump (Arc) electricity in the air gap, how much more with this?


Image


Yep!

FWIW, the spark plugs have no positive streamers and negative streamers charging continuously at any given instant of time. Lightning happens when both of these meet and their path becomes of "negligible resistance" per se. I believe the free space attenuation loss is 120 pi, so that is nothing to the mega volt charge of lightning.
But then again........what do I know.

PostPosted: Sat Sep 09, 2006 5:25 am
by stereophile
jonas- Hi. Guess what, the other day I had a referral to see a patient struck by lightning :!: :shock: He lived to tell the tale: He was having a bad round of golf with some buddies in a GC in Cavite. It started to rain and he heard thunder. He asked his caddie where the nearest shelter would be. She said it was two holes away. He decided to seek shelter beside a tall coconut tree with an umbrella in his right hand and a golf club in his left. There was a flash of light, then...BOOM :!: :!: :!: He was thrown a few feet by the blast :!: :shock: He did not lose consciousness, but suffered electrical burns. He was rushed to a clinic where his wounds were cleaned and stitched. He had a 1.5cm entry wound on his right palm and two 1.5cm exit wounds on his left palm. The jolt of electricity traversed his body from one hand to the next :!: The wound edges were a little singed, but except for these and some swelling and numbness the patient was ok. I told him that he was extremely lucky to be alive.

Moral of the story: When you hear thunder and see lightning, stop play and seek shelter immediately. Do not stand in the open or near trees. Do not hold an umbrella nor a club.


I tell you this tale because you may not be as lucky as this patient. Learn from this patient's mishap.

I am now wondering if the massive jolt of electricity 'recharged' his game. :roll: The next few rounds will reveal if his handicap increased :D or decreased... :cry:

PostPosted: Sat Sep 09, 2006 5:51 am
by jonas
stereophile wrote:jonas- It started to rain and he heard thunder. He asked his caddie where the nearest shelter would be. She said it was two holes away. He decided to seek shelter beside a tall coconut tree with an umbrella in his right hand and a golf club in his left. There was a flash of light, then...BOOM :!: :!: :!: He was thrown a few feet by the blast :!: :shock: He did not lose consciousness, but suffered electrical burns. He was rushed to a clinic where his wounds were cleaned and stitched. He had a 1.5cm entry wound on his right palm and two 1.5cm exit wounds on his left palm. The jolt of electricity traversed his body from one hand to the next :!: The wound edges were a little singed, but except for these and some swelling and numbness the patient was ok. I told him that he was extremely lucky to be alive.

Moral of the story: When you hear thunder and see lightning, stop play and seek shelter immediately. Do not stand in the open or near trees. Do not hold an umbrella nor a club.



since the coconut tree wasnt burned, i guess the lightning struck him directly? there was this show on TV where the lightning struck the water on a football field and all those who were playing football either fainted or got very weak and needed to be brought to the ER. also related to your story, when I was in high school, I remember caddies telling me that i shouldnt bring those umbrellas with the metal points/ends since that attracts lightning. what happened to his umbrella and the club (what club was it?) baka lucky club na ala "the natural"?

PostPosted: Sat Sep 09, 2006 6:00 am
by stereophile
The lightning hit the coconut tree first because it got burned. I guess some of it still hit him directly, since he has entry & exit wounds. I 4got to ask about he umbrella. Yes, it was a graphite club. He didn't say much about the golf club though, so it must be ok.

PostPosted: Sat Sep 09, 2006 11:43 am
by JackD201
[L]es wrote:CS ?


Ooops CSI throw in Myth Busters na rin they actually proved that it can happen.

PostPosted: Sat Sep 09, 2006 3:28 pm
by amandarae
stereophile wrote:jonas- Hi. Guess what, the other day I had a referral to see a patient struck by lightning :!: :shock: He lived to tell the tale: He was having a bad round of golf with some buddies in a GC in Cavite. It started to rain and he heard thunder. He asked his caddie where the nearest shelter would be. She said it was two holes away. He decided to seek shelter beside a tall coconut tree with an umbrella in his right hand and a golf club in his left. There was a flash of light, then...BOOM :!: :!: :!: He was thrown a few feet by the blast :!: :shock: He did not lose consciousness, but suffered electrical burns. He was rushed to a clinic where his wounds were cleaned and stitched. He had a 1.5cm entry wound on his right palm and two 1.5cm exit wounds on his left palm. The jolt of electricity traversed his body from one hand to the next :!: The wound edges were a little singed, but except for these and some swelling and numbness the patient was ok. I told him that he was extremely lucky to be alive.

Moral of the story: When you hear thunder and see lightning, stop play and seek shelter immediately. Do not stand in the open or near trees. Do not hold an umbrella nor a club.


I tell you this tale because you may not be as lucky as this patient. Learn from this patient's mishap.

I am now wondering if the massive jolt of electricity 'recharged' his game. :roll: The next few rounds will reveal if his handicap increased :D or decreased... :cry:


His biggest mistake......was to be under the tree(any tree) in a lightning storm. This is a no-no in such a situation. The umbrella is nothing (nor a car, etc.), but the tree.........