EMPs come in all sizes: from "You need a Very Sensitive meter" to all the way up to "Toasts the Earth".

My Power company offers a Spread payment on a "Whole House Surge Suppressor". Something like that will provide as Robust protection as is presently available. I have it. Goes between Your Meter and the Box. Has a Tell-tale to inform You if it is still on-line.

 

Just build a Faraday cage around your house and you will be fine.

 

House wiring and terminal devices will not be affected by any form of an EMP. Supposedly only electronic devices connected to the grid might be affected by the perceived power surge due to an EMP event.

 

This is incorrect: during 1859 Carrington event telegraph wires were on fire and all kinds of fires in telegraph offices.
No protection is possible (as far as I know) for a civilian dwelling. On the other hand it might not be important: if the Event so strong as to burn the wiring, one would have other issues much more important. Like dying from the Event or its consequences. Or living in the world without electricity.

 

It may or may not. Lots of variables. Plan on it frying and possibly starting some fires.

You can protect it somewhat by putting EMP protection on the input from commercial power using thyristors, but if the house is not protected itself as a Faraday cage, the house wiring could pick up enough energy to fry the wiring as well as what is connected.

One way to reduce (not eliminate) this risk is to have all the wiring, from the meter box right up to the connection boxes (which should be metal) in metallic conduit, with the whole system well grounded.

This might not totally prevent damage, but it should significantly help prevent the spread of any fires caused by over heated wires.

It is much better to be prepared for everything being destroyed, and having at least some backups protected in Faraday cages.

Just my opinion.

 

You can protect it somewhat by putting EMP protection on the input from commercial power using thyristors, .

I think that a metal-oxide varistor (MOV) would be the proper device to use for voltage transients caused by a CME or EMP. Even MOV's might not be 100% effective, because the rise time of the voltage spike from a EMP would exceed the MOV's capability to respond. MOV's are usually considered a single event device, since one lightning strike or large transient can require replacement of the MOV). Given that some transients can come in waves, if the first transient takes out the MOV then later transients can still do damage. This is not saying that you should give up trying to protect your house. I use MOV protected strips to protect my stuff also. Just be knowledgeable about what you are using, and why.

PS It might be worth contacting your local utility to see if they have any information on what is available.

These have been EMP tested to control arcing in homes. These will work in older homes, so no change in the wiring.

http://communities.leviton.com/serv...m/servlet/JiveServlet/downloadBody/2684-102-1-4245/Spec 5280 5380 7280 7380.pdf

 

Difference Between EMP And CME ...

A EMP is extremely powerful and extremely quick. Some idea how big. 1) Scruff across a shag rug then touch a door knob. Zap! Ouch. 2) A direct hit from a mega lightning strike. Blam! 3) A small EMP strike. 4) A big EMP strike. All in kinda in order giving a feeble idea of the energy involved. Small, big, bigger for sure and oh my Gawd! All very quick indeed. Like an instant.

We were taught that an EMP is thousands of times quicker than a lightning strike.

A CME like the Carrington even was a coronal mass ejection due to probably a X1000 or higher solar flare. Very powerful. Very drawn out over time up to days but certainly minutes and probably hours. A CMP will fry any length of conductor, be it elevated, on the surface or in a house or even buried ... IF the length of wire or what ever conduit is long enough. Minimum length?

Shorter the better? Longer the not better?

Dunno. Maybe a few hundred feet. Maximum length? Probably a few hundred feet to get things cooking and longer the worserer. Very long conduits like miles of power lines or big towers, buildings or phone cables would definitely be affected. Both an EMP and CME are very dangerous. The EMP lasts only an instant. A CMP can go on for days. Either would set us back 150 years.

Different events. A CME is natural. A EMP most likely man made and deliberate.

If one can protect electronical devices, they might get through a big CME. Not enough area to be zapped if separated from other conduits. A big EMP can and will fry un protected electronical stuff if non protected. Different events. Kinda different methods but perhaps the same eventual damage. Pick your poison. Either would destroy lots of modern stuff we use everyday.

 

One thing that people forget about the Carrington event.. it happened during the infancy of electrical transmission. Wires weren't insulated well if at all. Grounding wasn't nearly as effective as modern systems. Disconnects and switches were not available or were very slow or manual.

Not saying that crap wouldn't happen during another event of that level, however, some of the effects that occurred then may not happen at all in present day systems. However, other end user device effects could be magnified.

 

Our main line into the house is grounded 6 inches deeper than code, against bedrock, and has a plastic pipe inside the wall to the fuse box. Would a NEMP cause a fire in my house?

 

Probably not. But the grounding doesn't work for EMP: the event is way too fast.

 

If you are serious about protecting your home from an EMP look up the Halo PDCE. I think its overkill for your home. This is more for your concrete bunker. As a side benefit, you and all your neighbors will be free from direct lightning strikes, so check one more thing off the list.

Just remember, if there is enough radiation or electromagnetic energy to not trip your main breaker and catch your home wiring on fire, you'll likely already be dead.

PS - I have no affiliation with the company that makes the product. I build hardened critical infrastructures for the private sector.

 

Apples, oranges, or possibly kiwi fruit

 

If your house wiring burns up in an EMT strike then you burn also

 

So you mean it buried deeper than code requires? That will help somewhat, depending on the soil type and moisture, in reducing the energy pickup between the transformer and the house, which is where most of the energy comes from. Dry sandy soils won't matter much, with wet clay it will make a huge difference.

In electrical work grounding and earthing refer to making an electrical connection to the earth, while buried or underground refer to installing something in the ground.

 

EMP's come in two basic wavelengths. Long and Short. Solar events produce long wavelength pulses that induce voltage and current in long runs of wire, say a transmission grid, will overload connected devices with higher voltage and current than they are designed to carry thus destroying them. An electronic device not connected to the mains grid does not have the lengths of wire inside to effectively capture the pulse in a long wavelength event, so most of those will survive.

Nuclear blasts produce short wave EMP pulses, and most household electronics are susceptible, albeit to varying degrees. I've seen videos of testing various containment methods with high-power radio emitters proving that just a small gap in the containment structure can let in the pulse, but at a weakened strength.

So the protection methods for long and short wave pulses is different, as well as the integrity requirements of the containment device, relative to the strength of the pulse. All of these variables are nearly impossible to predict. The only practical preparation is to duplicate important electrical gear in containment devices, including batteries, chargers, solar, comm, etc. and unplugging things from the "grid" when not in use, the theory being only things plugged into the grid will be susceptible to a long wavelength pulse, although still susceptible to a short wavelength pulse.

 

The wavelength information is something i was looking for, but I was also going to add that the effects also vary wildly depending on the strength of the source. The electromagnetic waves induce current in wires they pass through, the only way this become dangerous is when enough current is generated to damage what is on either end of circuit, or to melt the interconnection itself. A HUGE amount of power would be required to actually melt house wiring, when you think that most circuits in houses are wired to carry more current than what the circuit breaker kicks out at, as a safety measure. As mrjaw said, the long wave lengths of solar magnetic pulses typically means electronics and short runs of wires would not be too likely to pick up these wavelengths, however i think the reverse is not true, short wavelength electromagnetic waves like would be generated by an EMP device or nuclear detonation can easily be picked up by transmission lines and household wiring, but the amount of power those devices are actually capable of generating pales in comparison to a big CME magnetic pulse hitting the earth directly. And of course you have to think also that anything which spreads in all directions like that is weaker, and the further you are from it, the less you experience. I would venture a guess that only those close enough to the blast to be directly effected(house blown down) would receive enough energy to actually turn your house wiring molten. The reason EMPs are so damaging to electronics is they are more sensitive, instead of a big heavy gauge wire to absorb all that energy, you are talking about tiny gauge wires, and thin traces of copper in circuit boards, all the way down to nano meter thin interconnections inside of processors. Very small amounts of additional current can over load such small thing pieces of metal.

I really think house wiring itself is pretty safe, the problem is in the event of a short wave pulse, damage to electronics, and in a long wave pulse, overwhelming current coming into the house from the transmission lines. An electrical engineer can probably design an overvoltage protection circuit to prevent carrington event type levels of energy from overloading your house and melting wires.

 

The frequency domain range from any EMP event produces infinitely wide band width ranges. There is absolutely NO DIFFERENCE between protection methods over frequency range.

Might go take a course in BASIC ELECTRICAL ENGINEERING theory before giving us this long BS.

 

First off, wear your seatbelt when you're in your car. I mean it. Accidents WILL happen. EMP statistically will not happen. Your life is better spent preparing for things that have and will happen again, and only when every single plausible and possible situation has been prepared for, you may then prepare for an EMP.

That said, I play with lighting simulation equipment for a living and I posted a very long dissertation on EMP for those who believe every mylar bag faraday cage retailer on the web. It's as low a level as I could make it, yet if you're concerned about EMP, then you need to read this. I know what powerful lighting, magnetic fields, electrostatic fields, and other sorts of electromagnetic events do to all sorts of things, and while you might get lucky, you can't assume any of your planning for EMP will do you a lick of good. Your government has spent billions to protect their assets against EMP and it's still wishful thinking and finger crossing as to whether or not it will all work or not.

Plastic conduit is pointless in EMP. Metal conduit has dubious value and can make it worse. Your wiring probably won't catch on fire but it will likely rip itself from the walls. Your small appliances might explode or go pop, but they won't catch on fire. Filters, noise arresting devices, or any of that other stuff won't do any good in protecting your Kardashian videos on your iPad. Whether or not your car will start has nothing to do with whether it has points or electronic ignition. If you're lucky and have a working cell phone after an EMP event, the cell phone towers are all toast, so don't bother. With the grid taken down and your generator toast, you should go ahead and learn to live without electricity.

Seriously, wear your seatbelt.

 

While I do not disagree that there are probably more likely events for people to prepare for, considering that some scientists think that incidents like the carrington event might be fairly common and we've been lucky so far, maybe it's not totally out there to prepare for it in some way. As far as nuclear EMPs go, I am not going to say it's a high likelihood, but you just never know. If you went back in time and asked a lot of people if they expected <insert historical event> they'd probably say no. We've almost let nukes fly on a couple occasions due to computer errors. I would still prioritize it below a lot of other disasters to prep for, but the way you are talking is like it would just never happen.

As far as I'm aware most people seeking to protect electronics in faraday cages are not protecting cell phones or tablets with kardashian videos >.> (pretty insulting to a lot of preppers really) More like radios of various types, which could actually be useful communication tools, and other more practical electronics.

 

I wouldn't expect all EMP's to be equal. Some would be devastating (super massive solar flare), some highly localized (lightning), some in between (weapon). Some would cause permanent damage, other systems might survive minor surges and reboot or reset.

You don't want to say they're all equal, therefore there's nothing you should do. I agree that if lightening hits my ham radio antenna, odds are high that my equipment will fry regardless of what I've done. If it strikes 10' away, 25' away, 100' feet away? At some point, added countermeasures will make a difference. Not in every case, but in some cases.

 

My original post was from information I studied long ago. I did find the same info presented below, albeit not where I sourced my info from.

http://www.survivalnewsonline.com/index.php/2014/05/protect-your-electronics-from-an-emp

If you do some emp research, and you know something about physics and waveforms, it's pretty easy to understand what happens. The link is pretty simplistic and dumbed down, but should describe the difference between a long wavelength carrington type event and a short wavelength nuclear emp. They are different, and affect different things different ways.

 

Another treatise from someone who knows just enough to be dangerous. It's NOT easy to understand. Electrostatics are one effect, magnetic fields and their massive forces another, and wave behavior are all occurring at the same time.
http://www.survivalistboards.com/showthread.php?t=182175

 

Guys, chill out. The point is there are different events. When someone says "emp" they can really be a variety of different things. I didn't say there were only two wavelengths of emp. I said they could be categorized, in general, as two classes of events. For 99% of use cases outside the military that's absolutely true. Everyone here doesn't need to geek out on all the scientific details. This isn't an exhaustive thread about emp theory. Most here are not going to spend huge amounts of time studying the underlying theory behind this stuff. I'm not doctorate level electrical engineer, but I'm not a novice either. The op asked a question and I tried to give a simplistic answer. I didn't say the whole volume of material is easy, I said if you understand some disciplines you can easily understand why a longer wavelength pulse affects something differently than a short wavelength pulse so the op can target his efforts toward protecting against a carrington type event or a nuclear event if he feels like one is more likely than another.

Aramchek when nasa looks at color they say the red part and the blue part of the spectrum...not that there are only two colors. Im doing the same thing here. I didn't say Emps were only in two frequencies.

CarlMc I didn't say the article was good, but someone asked for a source. Lots of sources say the exact same thing. It needs to be simplistic and easy to understand. Most people have no desire to learn the entire depth of knowledge on this subject, nor is that appropriate here. If you care to study, and subsequently know more than what most people are really wanting to know about, more power to you.

It never ceases to amaze me how rude people are here. All I'm trying to do is answer a question on a complex subject in layperson language. So no I don't appreciate the comment I know enough to be dangerous. understand the spirit of the conversation and keep your insults to yourself.

 

A large-scale EMP event would produce repercussions devastating to our way of life and the social order. The namesake Carrington event was in 1859,. Given technology at that time, no worry about loss of electricity, satellites, communications, GPS, etc. to the way of life, economy and technology.

I'd anticipate a complete reboot of government and our economy if the damage were severe enough. Imagine -- no credit card transactions, gas pumps not working, most paper-pushing jobs could not be done, banking and markets might likely come to a halt. Probably much of the military itself would be inoperable, especially the technologies that give us an edge over less-advanced armies.

If you think about it, many/most electronics today involve radio, satellite (GPS), internet or some other communications. So even if you saved a handheld GPS device, but the entire GPS network was down, it wouldn't matter. Probably another way to think about preparing for an EMP is to prepare for life without electronics -- and without law & order or a functioning economy. Amateur radio might still be a functioning communications medium, since the EMP's effects would not be evenly distributed, some hams might have protected their equipment, and it doesn't rely on a grid (except electricity).

 

I always thought an EMP would be a disaster. Everything is dependent on electricity. Medicines are delivered every few days to hospitals, pharmacies through inventory control systems. So there would be little help for those with serious medical needs like diabetes, etc. Food also. Are you saying a nuclear EMP would not damage most, if not all, electronics? I thought governments were not preparing for this possibility. Why do you believe EMPs are not a serious threat? I think it is a perfect way to destroy our country. Pretty confused.

 

Saying that EMP would be a total disaster is a safe assumption. There are way too many unknowns to say otherwise. A car on one side of the street may be toast, while the exact same model and year on the other side may be just fine. Assuming the worst is the best plan, and if things turn out to be less than that, then that's a bonus.

The military has certain installations that are EMP resistant, and that's essentially the intent of a small handful of people who make scientific, wild ass guesses. You're not on the list, nor are hospitals, communication providers, or anything else paid for by private money. The odds of an EMP are so low, and the costs to harden against it are so high, thus it simply doesn't pencil out for anyone but specific military and government applications.

Now that we've examined the cost/benefit side of things, the odds of you getting into a car accident are several orders of magnitude higher (hundreds of thousands, if not billions, in case you don't know what that means) so you stand better odds of surviving one if you wear your seatbelt. If EMP is a real concern for you, spend your money on learning how to live without electricity for extended periods, and do a careful analysis of your life and what the impact of electricity would be in the long term. If you're thinking about medical facilities, food and other goods distribution, and so on, you're already on the right track.

Me? I wear my seatbelt and worry about more pressing concerns.

 

You can get a whole house surge protector,it protects the entire electrical system in your house from power grid surges, but in the aftermath of such a event, there would most likely not be a electrical grid supplying power to your house anyways, so unless you have an off grid power source saving your house wiring would be a moot quest.

 

oops


double post

 

Typical surge arrestors and protectors use MOV's, and unless the market demands the energy rating necessary to protect against EMP, you wind up with blown up MOV's like the one in this Wikipedia article: https://en.wikipedia.org/wiki/Varistor (lightning strike, typical, with a much, much lower energy than EMP)

EMP transfers energy onto any wire, regardless of which side of the MOV the wire is on. Every wire looks like an antenna to a broadband magnetic pulse event, and the frequency that the wire ultimately resonates to is a function of how long the wire is, how sharp the bends in the wire are, and the termination types at each end of the wire. No MOV or surge protector of any type will protect everything in your house from EMP. You're not willing to pay what it takes to protect your home; there's definitely not enough of you to support a consumer market for those devices, and it's not like after an EMP event that you'll have warranty support anyway. You'll have bigger things to worry about. The frequency and action integral defines the rise time (is, actually) which, given the relatively decent response time of MOV's, the bulk of them will just go pop in very short order, leaving your precious electronic books completely unprotected.

But, if you want to spend your money on things you know nothing about (sucker born every minute, right?) then feel free to blow your money any way you want. Being a capitalist, I couldn't care less what you do with your money.

Ignorance is not knowing the facts. Stupidity is being provided the facts and ignoring them. I'm just some guy on the internet who says negative things about people who push false hope. Take it for what you paid for it. I get paid good money to work with electromagnetic effects (pulse power specifically) and I have no expectations that any product that I can afford will stop a fully loaded locomotive moving at near light speed, which I consider the simplest way to think of EMP. The lighting effects that I work with pale in comparison to full scale lighting strikes, not to mention the various EMP type events, and even in my relatively small scale work (15 Kilo joule ballpark,) certain electronic equipment and wiring configurations spell death for even the most hardened test equipment in our inventory. Not to mention the extreme hazard to the people working in the area. Dead before you know it.

 

An IEEE paper discussed corrections to a nuclear hardened maritime communication facility. Point was obvious. If a facility did not have protection from direct lightning strikes, then it also was not EMP protected. Solution was simple. How does that current exist without passing through the facility? Problem was routing of and excessive distance of connections from every incoming conductor to earth.

Same applies to homes. If not wired to make direct lightning strikes irrelevant, then EMP protection does not exist.

A properly earth 'whole house' protector does that. For homes, that protector must conduct at least 50,000 amps without failure. MOVs routinely do IF a protector is properly sized and installed. Protectors that fail on a first surge are grossly undersized (ie power strip protectors).

Connection to earth also must be low impedance as possible. That means a transient must connect to earth on a path that is as short as possible (ie less than 3 meters), no sharp bends, not inside metallic conduit, etc.

A current that need not enter a building does not do household appliance damage. If that standard protection from direct lightning strikes does not exist, then EMP protection clearly does not exist.

Neither EMP nor lightning would cause a fire. Fire is often created by something with greater energy - also called a follow-through current. Once EMP or lightning does damage, then a more powerful AC electricity might cause a fire. Fuses and circuit breakers must disconnect damaged appliances and wires BEFORE a follow-through current can create a fire.

 

Some of your statements directly contradict actual experiences, like CME of 1859, causing fires to telegraph offices. There wasn't AC current then, and DC current was very feeble. Moreover, the telegraph wires themselves could (and did) transfer the charges to anything flammable.

 

Thanks for the Lengthy Info Dumps and the Pointers, too, CarlMc! Lots for My Ham Radio and Engineering "Brain" to dig into.

Twelve Years, and thence into the past, I worked on what I thought were pretty big systems - 4160V, 600 AMP service, and 22KV substation feeding same. 500 VDC/2KA Crane Motors, and associated Gingerbread systems, control systems, blah, blah... Is good for me to see Bigger Dogs on the Internet - Puts me in my Place!

As Noted Waay long ago in this thread, I Have Whole House Surge Suppressor, as the threat of Brown-outs, Industrial Field collapses Spiking My Phase(s) - (Dairy Nearby) have meant I needed That protection. Ham gear is also Heavily grounded by shortest possible paths by Flat Copper Ribbon - One Inch by .100 inch. Looked into Silver-Plating to aid in handling Hall Effect, but had not done so - Yet. Check and Clean, and DeOxit all joins, once a Year, and Tighten. After Reading Your Info, not sure I will invest any more time or money than I have already! The Old Cost:Benefit ratio.

Thanks again!

 

Pulse power and distribution level currents are quite different, in that I can easily put 30kA though a 12ga wire for under 100 microseconds (generally avoided for assorted reasons, but possible.) Longer than that, and the magic smoke tends to come out rather violently, and I'm quite sure you've seen such things. It's about fusing current (Onderdonk, et al.) and that magical energy and time thing called power. Silver plating will buy you corrosion resistance but not much more. McMaster sells silver plated bus bars 1/4" thick by various widths, but you still have to cut and drill it, which is the nub of the corrosion problem. For your joints, put together as clean a joint as you can and soak it down with PJ1 motorcycle chain lube or LPS3 coating. The coating stays tacky forever, and fills in all the gaps that moisture otherwise wicks into and turns into that icky green stuff. This is why my car battery terminals never corrode.

You can give yourself a good bit of improved performance by mapping out all the grounds, both on the power and RF plane side, as well as the actual neutral current paths in your system, then going about and removing as many of the ground loops as possible. In pulse power, ground loops are dangerous to man and machine, but in the smaller scale they also put a lot of noise and losses in the system that are hard to track down methodically. Otherwise the entire thing needs a brute force ground plane, which is inefficient and wasteful.

 

Related enough that it was worth sharing:
http://metropolitan.fi/entry/airplane-triggers-lightning-burns-down-a-house-in-finland