But conveniently digs a trench for the replacement wires!





This picture is from reddit, so who knows how true it is. Interesting nonetheless.

While I’ve dealt with lighting damaged wires underground I’ve never seen anything like that

I highly doubt it dug itself up. Unless it was heavy gauge wire, 6 or larger. And with it being less than 12” deep and looks like it’s going to the fence.

This cable was dug up by a human.

KOT

When I installed and serviced invisible fences I regularly ran into lightning damage like this but on smaller scales. I’ve found entire fence 2000’ perimeters were the copper was gone and the jacket still in tact but brittle and crumbled when you touched it. And I’ve found section of the ground blown out, usually where there was a splice. I’ve never found an entire line with the ground blown out, but I have no doubt it’s real. Look at the jacket that’s left. It’s burn and brittle. If anyone had dug that up it would have been busted into pieces from the shovel hitting it.

"Lightning Trench"
[Link: google.com]:

Also, the displaced earth would be in more predictable piles, rather than randomly distributed as seen in the photo.

Yeah, but Lightning Trench.

A quick look at the energy in a lightning stroke: [Link: en.wikipedia.org]

With this much energy available, trenching is pretty easy. On the leading edge the copper is vaporized, and the vapor creates a large, hot, conductive path that will boil off the water, creating a steam explosion that vaguely follows the easier conductive path. Mega Volts and Kilo Amps are available, we don't care about a little resistance. Our beefy 300 Amp service is puny in comparison. Even our welders can only create a short arc and heat a point.

Another way of looking at this is that there has been a trainload of electrons thrown at a point and that inertial energy can't be absorbed at a point.

From the photo I guess that the earth was relatively dry, minimizing leakage beside the conductive path. (hence the longer path)

I think that this is a relatively rare event -- requiring a high energy strike and a nearby victim conductive path. Otherwise, we would all have one of these in our backyard. I saw some accounts of similar trenches following tree roots.

It would be interesting to have a high speed, stop action video of this trench building.

Lightning does some weird stuff for sure. One strike I saw was near a pole that had a camera at the top. Where the Cat6 went into the conduit at the base of the pole, the wire looked like it had exploded from within. The insulation on the individual conductors had melted a bit as well.

Another strike took out 8 analog cameras that were on a common power supply. It seems to have struck about 100' from one of the cameras, went up that run and down the other 7 runs on the secondary side of the power supply, yet the power supply itself was alright - didn't even blow the fuse on the primary side. Same strike killed the main boards on 3 out of 4 gate operators, an M-net gateway, 6 TPS-6Ls, a CCTV switcher, etc...

Last year, a customer called me about one of his cameras having gone offline. I tried a remote reboot and it didn't work, so I rode out and when I got the house, there were all these pebbles on the driveway, which I didn't think much of. Turns out it was a strike, and the pebbles were from where the lightning hit the top of the house, where there's this high standalone cinder block wall - it blew apart the corner of that and the exploded block was all over the driveway. The camera actually was OK, and one Samsung TV was killed. A Pioneer AVR was hung up and needed a reboot. At his neighbors house, it took out 3 Crestron MC3s and the 232 ports on his projector and Lite Touch processor.

On Monday, at one of my only commercial jobs, a strike took out their modem, router and PoE power of an IP phone.

Yesterday, we swapped out 4 cable boxes at another house, all smoked by a strike, along with a small Samsung TV.

That stuff keeps me really busy during the summer.

When there is a nearby strike, I try to justify replacing any electronics with a wire path to damaged units. Even if there is no obvious damage today, there could be subtle damage that will result in a future failure.

SWLFMike, you are in a fun area. I hope that you sell lots of surge suppression.

Knew a guy that added strike protection to all of the chimneys and roof ridge of his house.

First storm hit and blew off all six chimneys with major damage to the roof. One brick chunk landed on the hood of a Range Rover in the driveway.

Buzz - you wouldn't believe what a tough sell it is! Most of my clients have primary homes up north and are only seasonal residents down here. They don't see all the crazy weather, and when then all come back to town for Thanksgiving, my phone blows up because that's when they realize that their stuff got cooked over the summer.

When customers say, "But how did this happen? Don't I have a surge protector?", I tell them that stopping a close strike is like trying to stop a train with your hand.

During the prewire of one house that we still service, the guy running the job was there when one of the regular (daily, like clockwork) seasonal storms rolled through. Metal stud construction is the norm down here, and on this particular day, he said there were sparks coming from the metal studs during the storm, like static discharge flashes or something. I remember thinking, "This is going to be trouble...", and that house gets smashed nearly every year. It's right on the water, on a river that's brackish, so I've heard the grounds aren't too effective because they ground is saturated. I don't know if there's anything to that.

The follow up response from seasonal clients is "I can't believe this 3 year-old tv doesn't work, I only use it 5 months a year. Technically it's only a year and a half old."

Non-PC response: Ask them "is that how it works with your brain, too?"
PC response: You have to recognize that everything that exists degrades over time, even if only very slowly; also, some electronic equipment actually degrades more rapidly when it is not powered up on a regular basis.

Also a tough sell, but it would be worthwhile to unplug and isolate things during the off season.