Protecting equipment from lightning???
Protecting equipment from lightning???
(OP)
Hello all!
A guy I work with just read a book concerning computer hardware/software, and how to protect them from lightning. The author suggested that if you tie the cord in three knots (between the outlet and the computer) it will protect the computer from an electrical surge from lightning.
The idea is that when a high level of voltage travels through the cord and reaches one of the knots, it will block the high voltage from passing through the knots. He said to use three knots incase the first set don't get the job done.
Being an aerospace guy, I don't know whether or not to believe this, but I figured that this is a good place to pose the question.
Does this suggestion have any merit??
A guy I work with just read a book concerning computer hardware/software, and how to protect them from lightning. The author suggested that if you tie the cord in three knots (between the outlet and the computer) it will protect the computer from an electrical surge from lightning.
The idea is that when a high level of voltage travels through the cord and reaches one of the knots, it will block the high voltage from passing through the knots. He said to use three knots incase the first set don't get the job done.
Being an aerospace guy, I don't know whether or not to believe this, but I figured that this is a good place to pose the question.
Does this suggestion have any merit??
Regards,
Grant
Aerospace Engineer






RE: Protecting equipment from lightning???
There is no benefit at all by doing this to protect from lightning.
RE: Protecting equipment from lightning???
RE: Protecting equipment from lightning???
RE: Protecting equipment from lightning???
Thanks for your explaination. If I understand you correctly, the damage to the computer isn't caused by the direct voltage from the lightning, but rather the voltage going to ground via a path other than the computer cord? Then how does my computer get damaged? Sorry for the ignorance...
buzzp,
"There is no benefit at all by doing this to protect from lightning."
Why not?
rbulsara,
"Just let us know which aircraft will be using this technology!!!!! for our safety!"
I ain't tellin!
Actually, we try to dissipate lightning in aircraft, and try to route it out of the airplane via a path OTHER than the electrical and avionics systems... This is why we use static wicks on the trailing edges.
Regards,
Grant
Aerospace Engineer
RE: Protecting equipment from lightning???
RE: Protecting equipment from lightning???
The only thing that the knots in the power cord would do is restrict surge current flowing in the power cord. There will be no surge current flowing in the power cord unless something in the computer has flashed over, in which case it is too late to prevent damage.
RE: Protecting equipment from lightning???
Regards,
Grant
Aerospace Engineer
RE: Protecting equipment from lightning???
RE: Protecting equipment from lightning???
Practically however, after going through real inductive medium like transformers, conduits with many other cables carrying current, etc (unless of course, the lightning striked right next to the cord and induced a surge capacitively), I cannot see what additional benefit would the inductance of three knots do in terms of suppressing current (dimensionally, it would feel like a conductor for the surge anyways).
RE: Protecting equipment from lightning???
:)
Regards,
Grant
Aerospace Engineer
RE: Protecting equipment from lightning???
RE: Protecting equipment from lightning???
First string the power cord through a key before tying the knot. Use the second knot to tie a kite string to the cord. Go fly the kite during the next thunderstorm. Then ...
RE: Protecting equipment from lightning???
Well first off we need to define what this is suppossed to help and under what conditions. I believe we can rule out a direct strike (using the cord as path to ground) since the cord will be vaporized immediately.
I don't really care to take the time to explain why something so off the wall will not work. Ill leave you to figure that out by conducting some experiments. One loop is not going to do anything for you. The inductance of the wire itself is likely more effective at reducing 'transients' than one knot.
RE: Protecting equipment from lightning???
RE: Protecting equipment from lightning???
Most electronics is protected to some degree against some level of line spikes. A power strip with a circuit breaker and a MOV provides some additional protection.
RE: Protecting equipment from lightning???
A guy I work with just read a book concerning computer hardware/software, and how to protect them from lightning. The author suggested that if you tie the cord in three knots (between the outlet and the computer) it will protect the computer from an electrical surge from lightning.
The idea is that when a high level of voltage travels through the cord and reaches one of the knots, it will block the high voltage from passing through the knots. He said to use three knots incase the first set don't get the job done.
///There may be some analogy applied from the Lightning Air Terminal downwires that are supposed to form a smooth run from the air terminal to ground rods so that the lightning does not have to negotiate any turns thus not causing any path to some other conductive surfaces and paths to the ground (which would be unwelcome).\\\
Being an aerospace guy, I don't know whether or not to believe this, but I figured that this is a good place to pose the question.
///Real smart.\\\
Does this suggestion have any merit??
///In highly unlikely case that the lightning would actually travel along the cord, there would be some merit. However, the lightning peak power is so destructive that the cord knots will provide very little or negligible protection. Normally, the lightning elevates the potential on all conductive paths, surfaces and soil surrounding the direct lightning hit to the ground.\\\