Is it safe to use computer during lightning/thunder storm?

In order to confuse issues, some will hype nonsense about airplanes and then post insults as proof of his superiority. We are discussing a particular type of surge where a cloud conducts to earth. That is completely different from transients that transverse airplanes. Others have had this explained to them previously. To subvert the discussion, they insult and then throw in totally irrelevant topics such as airplanes.

Once ionization takes place, then capacitance of both sky (air) and earth becomes irrelevant. One of the best capacitors is air. However air gets converted into a good conductor (plasma) due to something called breakdown voltage. We require protection and only discuss surges after ionization has occurred. Surge current (not surge voltage) becomes the dominant variable after breakdown voltage is exceeded. Capacitance is made irrelevant.

Surge protecti> Surprised to see that no body talked about the capacitance of the

Nope, the full charge and current hits the airplane.

Just no.

If that happens then the antenna gets fried. Study up.

Huh?

NO, through your toes first.

OH NO another whole world surge protection wacko.

Nope.

years

has

in

for

like

w_tom == Suraj Singh

Check the headers

Perhaps you do not understand the relationship between thunder bolt and Earth. Lightening always searches a better path to the earth through a conductor and do not spare a non-conductor either if it needs.

Study up and try to understand this simple point.

Why the lightening is so hungry to get in to the earth?? Its the capacitance of the earth.

The capacitance of the Earth is very, very large indeed. This means that transferring charges to it will not significantly change its potential, any more than pouring jugs of water into the sea will significantly change sea level. So in the same way that we measure heights and depths from sea level so we measure potential from that of the Earth. We say that the Earth is at zero potential. The potential of an object is the potential difference between it and the Earth.

The capacitance of a normal adult is about 160 pF. This means if we walk along a nylon carpet and pick up a static charge of a millionth of a coulomb we shall be at a potential of more than 6000 V! If we then touch (about to touch) something earthed such as a metal door handle we may feel a slight shock, but the charge transferred to Earth is so tiny that it will do us no harm at all.

To protect CMOS chips from ESD we also connect a wrist starp to the chesis and do not bother to connect the whole thing to earth. but remember that lightening is not a tiny charge.

Read the last para of the following practical experience; see how the increased protection was provided by a faraday cage.

Suraj

Please stop writing abusive replies.

Checking the headers are your job. All others are here for helthy technical discussion.

You'd most likely be safe having that party, but it's gonna suck big time if your machine fries.

Kent

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Nie'se schlect sim'wa

Well, the OP did only ask about computers.

Actually, airplanes do get hit. Probably more than most people realize, although I don't have any actual cites to offer.

Kiss that antenna good bye. It's toast.

Eh? If you had a much bigger mass than the earth, you couldn't possibly be ON the earth. You couldn't possibly fit.

Which is why I think everyone should invest in a wireless optical mouse :)

No they don't, actually. Power strips are nothing more than additional outlets. Surge Protection strips can add a degree of protection. These are two different things. Always keep that in mind.

Kent

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Nie'se schlect sim'wa

Question

How is a plane protected from Lightning strikes?

Asked by: Sridhar Narayanan

Answer

Since the outer skin of most airplanes is primarily aluminum, which is a very good conductor of electricity; the secret to safe lightning hits is to allow the current to flow through the skin from the point of impact to some other point without interruption or diversion to the interior of the aircraft. Estimates show that each commercial airliner averages one lighting hit per year but the last crash that was attributed to lightning was in

1967 when the fuel tank exploded, causing the plane to crash. Generally, the first contact with lightning is at an extremity...the nose or a wingtip. As the plane continues to fly through the areas of opposite charges, the lightning transits through the aircraft skin and exits through another extremity point, frequently the tail (as shown by Gauss's Law).