Posted on 04/10/2013 6:45:54 AM PDT by Mr. K
The reality of protecting all electronic equipment against EMP from a nuclear explosion over our shores is becoming imminent. We now live in perilous times.
The information to follow on building "Faraday cages" is timely indeed. A single atmospheric nuclear detonation releases enough electromagnetic pulse (EMP) to equal 100,000 volts per square centimeter on the ground. A single detonation 200 to 400 miles over the center of the continental United States would fry every unprotected computer chip from coast to coast, and from the middle of Canada to the middle of Mexico. And we are now into Solar Cycle 23, with solar flares common and expected to continue until the first of next year. CME's are capable of extreme damage to modern computerized equipment! Sure, we have our windup BayGen radio's and spare lap top computers, but unless electronic equipment is protected from an electromagnetic pulse, they will be fried!
When Einstein and the others first refined and purified uranium, they took time off and studied its properties. That is when they discovered the "rays" that were harmful, as well as the phase transformations. In the course of their work, one of the scientists discovered that simply covering an object with a grounded copper mesh would stop virtually all electromagnetic radiation, whether proton or neutron. Obviously, they had to protect their monitoring equipment! Thus was born the "Faraday cage."
The copper mesh, like 1 inch chicken wire, worked well in large uses, like covering buildings, and it is still in use today: FEMA headquarters buildings are dome-shaped earth-bermed structures, and under the earth is a copper mesh that extends out from the base and is secured by grounding rods.
As an Electro Magnetic Pulse (EMP) travels to earth, whether from a Coronal Mass Ejection (CME) or a nuclear detonation in the atmosphere, it hits and runs along electrical power lines as well, building up voltage and amperage, which is what happened during the last solar storm a dozen years ago, blowing out transformers and leaving 6 million people in eastern Canada without power for weeks.
To prevent that problem, if you have a hard-wired generator, the wiring from the generator to the house should run in conduit that is grounded. The generator itself can have the frame grounded for added insurance, but that ground wire MUST be insulated and run to a different ground rod well away from the ground rod for building and conduit!
With radio's and smaller appliances, a Faraday cage can be built by using two cardboard boxes: one should fit tightly inside the other, and the item to be covered should itself fit reasonably well inside the smaller box. That is about the most work involved--finding the right size boxes! The outer box is then covered with aluminum foil or Mylar, as from a cheap "space blanket." A grounding wire is then taped to the foil. I then cover the foil with black 6 mil plastic, taped securely in place, to protect the foil from ripping. At the end of the ground wire I attach a cheap small alligator clip from Radio Shack. The item to be protected is placed inside the inner box, which acts as insulation from the outer box, and any EMP hitting the foil and is bled away by the ground wire.
Some medium sized electrical equipment can also easily fit into boxes covered with foil for EMP protection. My laptop computer, for example, fits easily into a Faraday box made from a box that held reams of paper: the entire lid is removable, allowing easy access to the laptop in its case, but is safely stored when not in use.
For larger items which cannot be boxed, such as living room TV sets, etc, I tape a Mylar space blanket to a piece of 6 mil black plastic sheet, using double-sticky tape every foot or so to make sure the Mylar stays in place (it is slippery). I leave a 2 inch edge of black plastic showing all around the space blanket, and while taping down the edges I put on a short lead of ground wire. When it appears that EMP or CME's are on the way, the blanket can be draped over the appliance, the alligator clip attached to a small, unobtrusive ground wire behind the cabinet, and any electromagnetic radiation will be diverted to the ground wire. Very cheap, simple, and once done, items can be "draped" for protection very quickly indeed. And the plastic blankets fold up neatly for storage, ready for use when needed.
The time to build Faraday cages or blankets is NOW, as when they are actually needed it will be far too late. Each box should be labeled on the ends and the top for the exact appliance they were built for, to eliminate any confusion when they must be protected in a hurry. Any electrical appliances not in use should be stored in the Faraday cage, where they will be kept clean, neat, in a known location, and protected against any sudden EMP surge.
Someone asked about Faraday Cages and EMP - This is probably very useful information for preppers and freepers.
It won't do you any good to have a generator to run your electronic equipment after the SHTF if it is all fried.
Even so, most comm will be down.
The internet will be toast.
The only thing you’ll be able to do with your farraday-protected computers is play video games. By yourself.
Nevertheless, I’d rather have what I don’t need than to need what I don’t have.
This would require non-aluminum metal conduit, correct?
OK so you make your Faraday cage and put your cell phone, radio, and electrical appliances in it. Then along comes the EMP and fries all the cell towers, radio transmitters, and electrical generating stations. So...whaddya got?
While the EMP threat is real, methinks that field strength is Volts/meter...not volts/square centimeter.
And 100k volts per centimeter would be a pretty good field...one which is more than enough to have lightning bolts flash out of the blue. One wouldn’t have to worry about EMP, since we’d all be electrocuted anyway.
Just thinkin’.
If you toss a blanket like this over your appliances the grounding wire can be inserted into the grounding prong in a 3-prong electrical outlet- not as good as a nice copper rod driven into the ground outside but way better than nothing.
GROUNDING is very important - if your house is not 100% 3-prong electrical outlets WITH EXCELLENT GROUNDING then it is as good as having nothing.
Your water pipes are usually really good grounds too.
I am not an electrician, I dont even play one on TV, so if there are any here PLEASE correct me if I have gotten anything wrong.
Put your cell phone in the microwave oven.
Or your butt.
Both, if they’ll fit!
I dont think so- I think Aluminum is a good conductor
(PLEASE CORRECT ME ANYONE IF I AM WRONG)
Please don’t misunderstand this reply. I think considering how to prep for an EMP or Solar event is very wise. What I don’t understand is the logic of trying to protect a generator that will require fuel which will quickly become unavailable following any event that takes out major power distribution facilities, transformers, etc.
Why try to protect a TV? I do think it makes sense to have rechargeable batteries, a solar system to provide some basic recharge system, a solar water pump, etc.
Interesting question. I have also read that grounding is not advised as the ground is the source of the surge.
We've bought a lot of non-electric stuff from Leihmans nonelectric store. It's saved us a number of times when the electric goes out because of a northeaster, or an appliance breaks. The nonelectric back up comes in handy.
A single atmospheric nuclear detonation releases enough electromagnetic pulse (EMP) to equal 100,000 volts per square centimeter...
I don’t think this guy knows what he is talking about. The bomb releases a magnetic pulse that is NOT electrical. The moving magnetic wave creates electricity in conductive metals. Antennas are perfect for generating an electrical pulse that can destroy things. The voltage would be dependent on the strength of the magnetic pulse.
I’ve heard the trash can thing works pretty well. For some reason it’s said to line the can inside with cardboard.
But it is not magnetic. It may keep an electric field from passing but not a magnetic.
His laptop?
Really?
He goes through all of that packing and unpacking before and after every use?
These measures only make sense for infrequently used or Emergency Use Only type items.
Water pipe grounding assumes a metal pipe going into the ground from your house. I know for a fact my source lines are plastic. No joy.
For smaller electronics, the easiest Faraday cage is a metal trash can that has no holes in the outside. Ground the trashcan with a metal rod and a connecting wire. Put a non conductive rubber mat in the bottom and around the sides so that nothing can touch the metal. Put your sensitive electronics inside.
“This would require non-aluminum metal conduit, correct?”
First of all, conduit is not made out of aluminum, It’s made out of galvanized thin wall iron pipe. Aluminum is actually a better conductor but it is too expensive and corrodes too easily.
Secondly, a grounded sheet stops an electrostatic field, but it is not in itself a “Faraday cage”. A Faraday cage actually doesn’t have to be grounded to be effective so long as the item to be protected including the power cords etc., are within the cage.
The Faraday cage works on the principal (discovered by Faraday), that an electric field inside of a conductor will always be zero because the electrons inside the metal always move in such a way as to always cancel the external field.
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