Unless you ground your rail through a lightning arrestor, it will also ground out your power supply if you're using track power and nothing will run. The only safe thing I can think off is to totally disconnect all power from the track and have some way of then connecting a ground wire to a water pipe or other permanently grounded metal. Under normal circumstances, lightning should not strike track that is on the ground because it always seeks a high point such as a light pole.
Yes. A few years ago there was a garden railway blown to bits by lightning.
His suggestions were to disconnect the power going into the house, and if you have track going in, leave a 3ft or so section removable so the outdoor track is completely separated from the house.
I've been involved in direct lightning strikes and it aint' pretty! Bottom line is that there is a very, very minimal chance of ever getting zapped, but if it does there is not much you can do about it. Disconnect the power supply either by unplugging it or disconnecting the power cables to the track.
Personaly I wouldn't even worry about it.
The Dixie D Short Line "Lux Lucet In Tenebris Nihil Igitur Mors Est Ad Nos 2001"
Once the lightning hits the track (an extremely unlikely event) on the way to the ground, it's only a few mm from the rail to the ground, so it'll prefer that direction to a 3 ft gap to the track in the house.
It does rather spread out when it hits the ground, especailly if the ground is water, causing lots of damage over a wide area.
On the other hand, if you're relying on an insulator to keep lightning from striking, forget it. It has jumped thousands of feet from the cloud to you, the few inches around an insulator isn't any obsticle. Susan used to figure she was safe on a tractor as long as she didn't have an implement in the ground 'cause there's 8 inches of rubber tire.
A direct strike on a lightning rod tends to blow the thing up. Lightning rods and such, including the wire on top of a power line, work by dissipating the positive charge that moves along the ground under the cloud into the air, encouraging the lightning to strike somewhere else. That's why they put that ground wire up there.
Lightning is bazillions of amps turning on and off many times in a few microseconds. This results in a huge, changing magnetic field. What happens when a changing magnetic field meets a conductor like a power line? This is the cause of most lightning related electrical trouble. Fortunately, the lightning tends to be a vertical current and the conductors horizontal so it doesn't couple very efficiently. The results of this inefficeint transfer of energy can be alarming
Living out in Eldorado Township, our big walnut trees got hit several times. Not a pretty sight! Never had damage to the house from lightning, but it did blow up a cordless phone once.
The most common lightning injury is burns on the foot.
Small point of order-
Lightning travels UP, from the ground to the clouds. It is a static discharge from the Earth.
In any case, it can do a lot of damage, but the chances of your rails getting zapped are so small that I wouldn't give it another thought. It is more important to unplug or disconnect your power supply so any stray voltage from EMP induction or power spikes from lightning strike elsewhere won't destroy your electronics.
Oh dear oh dear, Torby, I had hoped this wouldn’t be necessary but since you blamed Edison, I'll blame Newton…………
Lightning can be described as an electrostatic force. This force depends on the amount of charge and the distance between the objects. You can calculate the force using Columb’s law of Force equals Point charge magnitude one times Point charge magnitude 2 divided by the distance squared. This happens, by no small coincidence, to exactly coincide with Newton’s law of gravitation. The forces in both laws depend on the inverse square of the distance between the objects and are directed along the line between them. I won’t get into the vector sum of 3 or more point charge magnitudes (which make multiple hits from one lightning strike), but the reasoning is the same. Since lightning comes from no small distance, perhaps 1,000 meters or greater, you can see by the formula that the electrostatic force is very high to bridge the gap from ground to cloud.
The cloud bottom carries a negative charge. Positive charges (excess electrons from induction but we won’t get into that) collect on the ground. A stepped leader—a negative electrical charge made of zigzagging segments, or steps (calculated using Columbs law)—comes partway down from the cloud. The steps are invisible; each one is about 150 feet long. When the stepped leader gets within 150 feet of a positive charge, a streamer (surge of positive electricity) rises to meet it. The leader and the streamer make a channel. Since electricity move from Positive potential (+) to Negative potential (-) the discharge of static electricity (free electrons) from an object on the ground surges upward through the channel thereby touching off a bright display called a return stroke.
Under most conditions the earth is a good electrical conductor, therefore when a metal wire is attached between an object (your house or railroad) some of the free electrons leave the object and distribute themselves over the much larger earth. This is known as a form of charging by induction and is how a lightning rod works to protect your house or railroad. It doesn't work 100% of the time due, as we discussed earlier, to the inverse square of the distance being very high (as stated before, 3ft won't make much of a difference).
Ok, so I majored in physics, don't blame me, blame Newton and Columb………..
Like I said, I wouldn't worry about it.
Pretty darn good, one small omission, in about 5% of the cases, the leader can form from the top of the clouds and be positive, and the streamer is negative, so there are cases where the polarity is reversed. But the majority is as you say.
Also, electricity does not move from positive to negative in the general sense. If you are talking about electricity like in a battery, only the electrons actually move. They move from the negative terminal to the positive terminal.
If you are talking about static electricity, you are talking about positively charged atoms and electrons. They both move. In this case you can really pick any convention you want since both are moving, the positive towards the negative and the negative towards the positive. The basic thing is once the leader is formed, the lightning jumps up from the ground/building/tree/lightning rod/railroad track, i.e. the path of ionization that makes the flash and the boom.
I majored in Physics too, and have a degree in it ;-)
Visit my site: http://www.elmassian.com - lots of tips on locos, rolling stock and more.
Click here for Greg's web site
Agreed, Greg. I gave a very "Reader's Digest" version, and it was late and I was thinking of conventional current, but the thrust of it is correct. It would fill quite a bit of band width on the forum to properly discuss the mechanics of a lightning strike, but I'll leave it at that.
As I stated before, I have been involved in direct lightning strikes during my military carreer and it's quite astonishing the unpredictabiltity (we got hit out of a clear blue sky) and power involved. Certainly nothing to fool around with and no time to anylize if the bolt went up or down.
In the early 50's, telegraph lines were still in use. Each tower and station had a terminal board and at times you would be asked to ground one of the lines so that a lineman could determine where the line fault was.
My first night in a an interlocker tower during a thunderstorm was quite an experience. Some men had interesting stories as to what they saw during a lightning strike near the tower. Never saw ball lightning but heard plenty of stories. The terminal board would make weird noises and would sort of glow at times. Never really got used to it and always stayed far away from it during a storm.
Art, the devout coward
That's close to what a mariner would call, "St. Elmo's Fire."
Spooky stuff. Harmless in itself, but often accompanied by other frightful things.
Torby wrote: That's close to what a mariner would call, "St. Elmo's Fire." Spooky stuff. Harmless in itself, but often accompanied by other frightful things.
Oh dear, oh dear............................ I don't have the enthusiasm for this one....................
What about prototypical track. I'm sure it is grounded in some way, but has there ever been any horrific lightning railroading events? One of my employees once told me she had seen lightning come out of the ground and go towards the sky. And all this time I thought she might have had one too many blood pressure pills!
Rich F.
Smoke Stack Lightnin wrote: What about prototypical track. I'm sure it is grounded in some way, but has there ever been any horrific lightning railroading events? One of my employees once told me she had seen lightning come out of the ground and go towards the sky. And all this time I thought she might have had one too many blood pressure pills! Rich F.
Tom Trigg
A sight to remember I'm sure! Just think of the thousands of miles of track naked to the sky, but thank God no major catastrophes, at least that I've heard.
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