EMP blast - what would happen really?

I've heard that if an EMP weapon were used, *nothing* in the blast area
that relies on electricity would work.

Is this really true?

If you had an alkaline battery, it would still put out a voltage,
correct?

Failing that, one could still take a roll of paper towels, immerse the
towels in a salt solution (table salt should do), place alternating
plates of copper and zinc (or any two dissimilar metals), and obtain a
current... right?

Would motors still work, or would their windings be guaranteed
destroyed in an EMP blast?

Thanks,

Michael

(E-Mail Removed) wrote:
> I've heard that if an EMP weapon were used, *nothing* in the blast area
> that relies on electricity would work.
>
> Is this really true?
>
> If you had an alkaline battery, it would still put out a voltage,
> correct?
>
> Failing that, one could still take a roll of paper towels, immerse the
> towels in a salt solution (table salt should do), place alternating
> plates of copper and zinc (or any two dissimilar metals), and obtain a
> current... right?
>
> Would motors still work, or would their windings be guaranteed
> destroyed in an EMP blast?
>
> Thanks,
>
> Michael

Michael - The EMP (electro-magnetic pulse) would not affect batteries.
In fact, it's really only a concern for IC's, especially
microprocessors. The big deal several years ago was that U.S. military
aircraft relied heavily on silicon ICs and microprocessors, but the
stone-age Soviet planes were still using vacuum tubes and the vacuum
tubes would be pretty much immune to a nuclear EMP. The EMP problem
goes back to Einstein, et. al. wherein a wave can also be an atomic
particle, which is true of course, and can, and does occasionally knock
out one bit of a memory cell, usually in spacecraft. However, the
caveat being that the nuclear blast causing the EMP doesn't evaporate
you and your battery cell, thereby leaving you no reason to worry abut
the EMP ))

Almo

(E-Mail Removed) wrote:
> I've heard that if an EMP weapon were used, *nothing* in the blast area
> that relies on electricity would work.
>
> Is this really true?
>
> If you had an alkaline battery, it would still put out a voltage,
> correct?
>
> Failing that, one could still take a roll of paper towels, immerse the
> towels in a salt solution (table salt should do), place alternating
> plates of copper and zinc (or any two dissimilar metals), and obtain a
> current... right?
>
> Would motors still work, or would their windings be guaranteed
> destroyed in an EMP blast?
>
> Thanks,
>
> Michael

After an EMP event, batteries will still hold their chemical charge,
electrical motors will still function (except, perhaps, for the
smallest micro-motors), relays will still function, as would
electron-tubes. The power grids will see a major overload, and
protection circuits will "kick" in. Whether they recover in a timely
manner is another subject.

What will be damaged are most unprotected electronic circuits: Consumer
electronics, TVs, radios, cell phones, iPods, Blackberries, hand-held
video games, home computers, etc. Even automobiles have so much
electronic gear (computers, sensors) that they would be rendered
useless after an EMP event. This is one [small] reason I keep a 1969
Chevy truck -- no electronics.

The key is the threshold energy: motors, generators, transformers,
relays, power-grid components, vacuum tubes all operate in the range of
10 milliJouls to >1 MegaJoules, while all consumer electronics
(integrated circuits) have a threshold energy at or below 1 milliJoules
(down to 100 nanoJoules and less). EMP pulses can produce 10
milliJoules inside of electronic circuits, and 100 Joules outside of
electronic enclosures.

The majority of military electronic gear has protection circuits
built-in so they would survive (at least they are designed and tested
that way).

almo wrote:

> Michael - The EMP (electro-magnetic pulse) would not affect batteries.
> In fact, it's really only a concern for IC's, especially
> microprocessors. The big deal several years ago was that U.S. military
> aircraft relied heavily on silicon ICs and microprocessors, but the
> stone-age Soviet planes were still using vacuum tubes and the vacuum
> tubes would be pretty much immune to a nuclear EMP. The EMP problem
> goes back to Einstein, et. al. wherein a wave can also be an atomic
> particle, which is true of course, and can, and does occasionally knock
> out one bit of a memory cell, usually in spacecraft. However, the
> caveat being that the nuclear blast causing the EMP doesn't evaporate
> you and your battery cell, thereby leaving you no reason to worry abut
> the EMP ))

Almo, you are confusing two very different things.

EMP is not an atomic particle sort of wave, but instead is essentially
a very powerful radio wave. It induces current in antennas -
intentional ones, and also any conductor that it encounters. When it
hits the huge antenna that is the electrical power grid, it can be
powerful enough to fry "big" things like motors, but when it hits
smaller conductors it can induce enough to fry sensitive things like
IC's (which often are more electrically fragile than tubes). The power
of the pulse-induced current does the primary damage, though there
could perhaps be some secondary effects.

But you've mixed it up with the effect of individual charged particles,
such as from radioactive decay or cosmic sources, on very small
structures in IC's. That's an entirely different matter - it cuases
erroneous operation and flips flip flops, but it usually
non-destructive, unless it triggers self-distructive current flow from
the ordinary power supply by putting an IC into latch-up.

(E-Mail Removed) wrote:

> almo wrote:
>
> > Michael - The EMP (electro-magnetic pulse) would not affect batteries.
> > In fact, it's really only a concern for IC's, especially
> > microprocessors. The big deal several years ago was that U.S. military
> > aircraft relied heavily on silicon ICs and microprocessors, but the
> > stone-age Soviet planes were still using vacuum tubes and the vacuum
> > tubes would be pretty much immune to a nuclear EMP. The EMP problem
> > goes back to Einstein, et. al. wherein a wave can also be an atomic
> > particle, which is true of course, and can, and does occasionally knock
> > out one bit of a memory cell, usually in spacecraft. However, the
> > caveat being that the nuclear blast causing the EMP doesn't evaporate
> > you and your battery cell, thereby leaving you no reason to worry abut
> > the EMP ))
>
> Almo, you are confusing two very different things.
>
> EMP is not an atomic particle sort of wave, but instead is essentially
> a very powerful radio wave.

Spot on.


> It induces current in antennas -
> intentional ones, and also any conductor that it encounters. When it
> hits the huge antenna that is the electrical power grid, it can be
> powerful enough to fry "big" things like motors, but when it hits
> smaller conductors it can induce enough to fry sensitive things like
> IC's (which often are more electrically fragile than tubes). The power
> of the pulse-induced current does the primary damage, though there
> could perhaps be some secondary effects.
>
> But you've mixed it up with the effect of individual charged particles,
> such as from radioactive decay or cosmic sources, on very small
> structures in IC's. That's an entirely different matter - it cuases
> erroneous operation and flips flip flops, but it usually
> non-destructive, unless it triggers self-distructive current flow from
> the ordinary power supply by putting an IC into latch-up.

A US test once knocked out street lighting in Hawaii !

http://www.fas.org/nuke/intro/nuke/emp.htm
http://www.sonic.net/~doretk/Issues/.../theblack.html
http://www.lewrockwell.com/wanniski/wanniski15.html
http://www.unitedstatesaction.com/emp-terror.htm

Graham

tlbs101 wrote:
> (E-Mail Removed) wrote:
> > I've heard that if an EMP weapon were used, *nothing* in the blast area
> > that relies on electricity would work.
> >
> > Is this really true?
> >
> > If you had an alkaline battery, it would still put out a voltage,
> > correct?
> >
> > Failing that, one could still take a roll of paper towels, immerse the
> > towels in a salt solution (table salt should do), place alternating
> > plates of copper and zinc (or any two dissimilar metals), and obtain a
> > current... right?
> >
> > Would motors still work, or would their windings be guaranteed
> > destroyed in an EMP blast?
> >
> > Thanks,
> >
> > Michael
>
> After an EMP event, batteries will still hold their chemical charge,
> electrical motors will still function (except, perhaps, for the
> smallest micro-motors), relays will still function, as would
> electron-tubes. The power grids will see a major overload, and
> protection circuits will "kick" in. Whether they recover in a timely
> manner is another subject.
>
> What will be damaged are most unprotected electronic circuits: Consumer
> electronics, TVs, radios, cell phones, iPods, Blackberries, hand-held
> video games, home computers, etc. Even automobiles have so much
> electronic gear (computers, sensors) that they would be rendered
> useless after an EMP event. This is one [small] reason I keep a 1969
> Chevy truck -- no electronics.
>
> The key is the threshold energy: motors, generators, transformers,
> relays, power-grid components, vacuum tubes all operate in the range of
> 10 milliJouls to >1 MegaJoules, while all consumer electronics
> (integrated circuits) have a threshold energy at or below 1 milliJoules
> (down to 100 nanoJoules and less). EMP pulses can produce 10
> milliJoules inside of electronic circuits, and 100 Joules outside of
> electronic enclosures.
>
> The majority of military electronic gear has protection circuits
> built-in so they would survive (at least they are designed and tested
> that way).


So vacuum tubes (and diesel generators) should still work... and here I
thought we'd have to go into hydraulic gates (some researcher in MIT
was working on these, I can't find the link at the moment) in the event
an EMP went off...

Thanks,

Michael

Eeyore wrote:

> (E-Mail Removed) wrote:
>
> > almo wrote:
> >
> > > Michael - The EMP (electro-magnetic pulse) would not affect batteries.
> > > In fact, it's really only a concern for IC's, especially
> > > microprocessors. The big deal several years ago was that U.S. military
> > > aircraft relied heavily on silicon ICs and microprocessors, but the
> > > stone-age Soviet planes were still using vacuum tubes and the vacuum
> > > tubes would be pretty much immune to a nuclear EMP. The EMP problem
> > > goes back to Einstein, et. al. wherein a wave can also be an atomic
> > > particle, which is true of course, and can, and does occasionally knock
> > > out one bit of a memory cell, usually in spacecraft. However, the
> > > caveat being that the nuclear blast causing the EMP doesn't evaporate
> > > you and your battery cell, thereby leaving you no reason to worry abut
> > > the EMP ))
> >
> > Almo, you are confusing two very different things.
> >
> > EMP is not an atomic particle sort of wave, but instead is essentially
> > a very powerful radio wave.
>
> Spot on.
>
> > It induces current in antennas -
> > intentional ones, and also any conductor that it encounters. When it
> > hits the huge antenna that is the electrical power grid, it can be
> > powerful enough to fry "big" things like motors, but when it hits
> > smaller conductors it can induce enough to fry sensitive things like
> > IC's (which often are more electrically fragile than tubes). The power
> > of the pulse-induced current does the primary damage, though there
> > could perhaps be some secondary effects.
> >
> > But you've mixed it up with the effect of individual charged particles,
> > such as from radioactive decay or cosmic sources, on very small
> > structures in IC's. That's an entirely different matter - it cuases
> > erroneous operation and flips flip flops, but it usually
> > non-destructive, unless it triggers self-distructive current flow from
> > the ordinary power supply by putting an IC into latch-up.
>
> A US test once knocked out street lighting in Hawaii !
>
> http://www.fas.org/nuke/intro/nuke/emp.htm
> http://www.sonic.net/~doretk/Issues/.../theblack.html
> http://www.lewrockwell.com/wanniski/wanniski15.html
> http://www.unitedstatesaction.com/emp-terror.htm

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Scrub that last link. There's loony stuff later on written by right wing
nitwits.

Graham

(E-Mail Removed) wrote:
> I've heard that if an EMP weapon were used, *nothing* in the blast area
> that relies on electricity would work.
>
> Is this really true?
>

Andy comments:

After reading the replies to your question, I am afraid that
they have missed the point.

The answer is , NO, you would not be able to download
porn until you bought a new computer.......

Sorry, ;.... but that's the fog of war.....

Andy in Eureka, Texas

AndyS wrote:
> (E-Mail Removed) wrote:
> > I've heard that if an EMP weapon were used, *nothing* in the blast area
> > that relies on electricity would work.
> >
> > Is this really true?
> >
>
> Andy comments:
>
> After reading the replies to your question, I am afraid that
> they have missed the point.
>
> The answer is , NO, you would not be able to download
> porn until you bought a new computer.......
>
> Sorry, ;.... but that's the fog of war.....
>
> Andy in Eureka, Texas


Porn, ha ha... they can use the analog solution: magazines.

I was more concerned with the future wars our administration will get
us into, but that's a whole 'nother story. In that case, the supply
chain involved with "buying a new computer" may not exist...

Cheers,

Michael

(E-Mail Removed) wrote:
> I've heard that if an EMP weapon were used, *nothing* in the blast area
> that relies on electricity would work.
>
> Is this really true?
>
> If you had an alkaline battery, it would still put out a voltage,
> correct?
>
> Failing that, one could still take a roll of paper towels, immerse the
> towels in a salt solution (table salt should do), place alternating
> plates of copper and zinc (or any two dissimilar metals), and obtain a
> current... right?
>
> Would motors still work, or would their windings be guaranteed
> destroyed in an EMP blast?
>
> Thanks,
>
> Michael

As you suspect, the statement that after a detonation of an "EMP
weapon", "nothing with 2 asterisks" in the "blast area" that "relies"
on electricity would work is a bit inaccurate and/or misleading. Much
electrical and electronic equipment already in existence would be
destroyed or damaged. Some would not. This undamaged equipment would
work fine after the pulse had gone by. Yes of course an alkaline
battery would still put out a voltage. If it was in a circuit it might
have got fried first. Of course if you made a voltaic pile out of wet
tissues and dissimilar metals it would work. An EMP device does not
abolish electric currents for ever within the blast area.

If by an "EMP weapon", you mean a nuclear device optimized for EMP (all
nuclear weapons produce EMP to some extent), they work by sending out
an electromagnetic pulse which would induce more or less heavy currents
in conductors. This could damage electronic equipment and electric
power lines, generating stations and substations.

The resistance to EMP by device is listed below, from most to least
vulnerable:

1. Integrated circuits (ICs), CPUs, silicon chips
2. Transistors
3. Vacuum Tubes (also known as thermionic valves)
4. Inductors, motors

Transistor technology is likely to fail and old vacuum equipment
survive. However it must be considered, that different types of
transistors and ICs show different sensitivity to EM: bipolar ICs and
transistors are much less sensitive than FETs and especially MOSFETs.

To protect sensitive electronics, a Faraday cage must be produced
around the item. This can be done by wrapping the item, such as a radio
in foil (any external connections should not touch foil) without any
holes. This will shield the item from EM fields.

So you can see that motors are fairly low down the list of vulnerable
equipment.

A strike *guaranteed* to burn out the windings in an electric motor
would most likely destroy the building it is housed in by blast or heat
anyway.

When a defecting (for money) Soviet pilot landed a MiG fighter in japan
towards the end of the Cold war, and US techs stripped it down, they
laughed at how "backward" the Soviets were, still using vacuum tubes in
the 1980s. Such dinky little tubes as well. Then they stopped laughing
when they noticed a couple more features and realised they were looking
at a practically EMP proof plane.