Just reading about how LED lites can last several times longer on the same batteries than conventional flashlites, and that they contain a circuit and a chip. Does anyone know if they are as susceptible to "frying" as typical commerical electronics by an Electro-Magnetic Pulse?
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Are the LED flashlites susceptible to EMP?
- Thread starter scotjute
- Start date
A metal flashlight body either ferous or aluminum or whatever will have some positive protection affect compared to a plastic body, but it does not cover the entire flashlight. The EMP has a window of opportunity, the clear part out front that the light goes through. Any metal falshlight with LED that is in use at the time wil probably get zapped.
I would say that the whites and newer blues and greens that all say no greater than 5V reverse voltage would be most susceptible, with some of the older tech yellow and red that were more forgiving of reverse voltage but less efficient would be less susceptible.
If the metal flashlight was setting on a metal surface face down, and the rim all the way around was not insulated by either anodized finish or paint or whatever, the protection could be pretty good. Any such flashlight stored in a metal container with non-insulated metal lid would have a good chance of surviving. 2 layer faraday cages are much better at blocking such stuff.
I would say that the whites and newer blues and greens that all say no greater than 5V reverse voltage would be most susceptible, with some of the older tech yellow and red that were more forgiving of reverse voltage but less efficient would be less susceptible.
If the metal flashlight was setting on a metal surface face down, and the rim all the way around was not insulated by either anodized finish or paint or whatever, the protection could be pretty good. Any such flashlight stored in a metal container with non-insulated metal lid would have a good chance of surviving. 2 layer faraday cages are much better at blocking such stuff.
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A simple metal housing only has a very limited effect in blocking an EMP - if at all. It's wrong to assume that a Faraday-box will protect electronics from an EMP - it protects stuff on the inside from electricity, but not from magnetic waves in the magnitude an EMP produces. Only very expensive metal alloys protect against an EMP, the main point is that there must be *no holes* whatsoever and the shielding should be made of one piece of metal, because any junctions are possible entry-holes for the EMP waves.
And it's not important whether the unit is in use at the moment of the EMP or not, if the EMP is inducing a strong enough current in the electronic parts, they *will* be fried.
BTW, if you experience an EMP killing your LED flashlights, you will probably have quite some other problems to think about first. ;-)
-Connor
And it's not important whether the unit is in use at the moment of the EMP or not, if the EMP is inducing a strong enough current in the electronic parts, they *will* be fried.
BTW, if you experience an EMP killing your LED flashlights, you will probably have quite some other problems to think about first. ;-)
-Connor
The trucks ignition system probably won't, but the LED ought to.
Since the electrical system grounds through the frame of all cars and trucks I know of, the frame and body will act as an antenna for conducting EMP to the ignition and charging system. Same goes for metal bodied flashlights out in the open. Faraday cages only work when the contents are not touching the cage directly. So line your metal box with foam or at least cardboard.
Since the metal body is part of the circuit, it will conduct EMP to the electronics. The metal body would only shield if the flashlight used a circuit separate from the body. A good strong EMP will probably blow the itty-bitty filament in your metal bodied Mag-Lite's bulb too. Having the switch turned off won't help as an EMP will cause an electron flow along any available path. Including back through the battery and around the wrong way.
pil sung - 'Crow
Just got thru reading the stuff on Candlepowerforums.com, last post todate on this was on 3/7/03. It appears that most think that if the flashlite is in a tightly enclosed metal box, but insulated from said box, that it may survive. Do a box within a box, or multiple layers of metal and insulating material and survival odds go up. Also metal bodied flashlites more resistant that non-metallic bodied lites. Cover the lens cap with metal and resistance increases. Someone even did experiment with 2 different LED flashlites in microwave. The metal bodied one survived (kept shining), the plastic bodied one did not. Forgot the test length, but belive they said it was just for a second or so.
I remember reading an engineering document put out by the military about protecting a structure against EMP. They used double doors that created an "airlock" type arrangement. Each door had a specially designed electromagnetic seal that had a tight metal-to-metal fit all around. Air vents were covered with elaborate screen systems. The general concept was that no openings were allowed to be more than a few mm in size. Another interesting thing is that the sheet metal for the walls had to be a certain thickness, else plane waves could penetrate.
By the way, has anyone heard if they used EMP (high power microwave) bombs in Iraq?
Scott
By the way, has anyone heard if they used EMP (high power microwave) bombs in Iraq?
Scott