when a crane touches a power line

[DirectTech]

This is what happens when a cranes cable touches a power line. http://video.google.com/videoplay?d...l=6&start=0&num=10&so=0&type=search&plindex=0

 

[skata]

damn

 

[Legdoc]

I would think the primary would trip due to the fault. It looks like time to roast some marshmallows with a long stick!

 

[Lashlander]

I've seen this video before and I'm surprised that the operator didn't get electrocuted or that it didn't burn the cable in two where it hit the power line.

 

[Canadian_digger]

The whole time I was watching that I was thinking they should not be looking at that and he finaly said it at the end of the video.

 

[Steve Frazier]

Not only should they have not been looking at the arc, but the spectators should not have been standing in proximity of the overhead wires. By all rights those wires should have burned off and would have fallen dancing around on the ground until the fuse popped. Those wires are a minimum of 13,000 volts and any one of those people could have been killed should the wires have burned and dropped.

Thanks for posting!

 

[Dozerboy]

WOW I'm suprised nothing popped. I was told if you ever hit a power line to jump off the machine. Having a hand on the machine and foot on the ground will light you up.

 

[Canadian_digger]

Jumping off the machine is right. But its better to jump with both feet together.

 

[DirectTech]

That is some strong current if it can melt the rear outrigger.

 

[digger242j]

One day on the job, a truckload of stone came in. The driver lined up right beneath a 30,00 volt power line, and raised the bed. Now, the line was at the top of the poles, and his bed would never have reached it, but there was a guy wire running from one pole to the other. The cab protector pushed up on the guy wire, which pulled the poles together, and let the 30kv wires sag, until the center one touched the guy wire.

I was facing the other direction, and when I turned around, there was arcing and flames all around the rear tires. It blew all 4 tires across the rear, and the passenger side front tire, before the conductor that was in contact with the guy wire burned through. That happened at just about the same time as the fuse tripped at the transformer on the far pole.

Fortunately, that was at the end of that line, so the downed wire was dead. Of course, so was the 9 story office building connected to the far pole.

In the video, I have to assume that that was some pretty heavy duty current in the wire, to have not blown a breaker somewhere along the line.

 

[Orchard Ex]

A guy working for our power company once told me that the big feeder lines don't have fuses like the smaller distribution lines do. If something shorts the big line the circuits just push harder to make up for the bleed loss until some thing melts or goes boom. :beatsme

 

[Tacodriver]

ouch

Those guys were lucky for sure . I wonder what buddy was thinking setting up that close to power line..

The linemen I have worked with have told me if the machine is not on fire it is safer to stay in the machine then risk jumping out. If the machine is on fire then you are forced to jump out.. Teh proper thing to do then is jump as far as you can and land both feet at the same time then shuffel away. The electricity radiates through the ground like rings from a rock thrown into a pond if you take a step possibly get a nasty shock or worse.


Another linemen told me a story about the haydays up in fort macmurray the contractors figured it was cheaper to pay to fix the broken line. the linemen were getting tired of fixing torn up lines. So they took the fuses out of the transformer on a distribution line and wired in solid copper. Needless to say the next line that got hit fryed the machine pretty good. After that contractors learned to call for locates.

 

[Countryboy]

It's better to stay in the vehicle or piece of equipment unless you are in immediate danger, an example being fire in the cab. MSHA and OSHA both teach this, as well as various power company training courses. The fact that you are sitting in the cab realizing that you have come in contact with a powerline means that you are currently not being electrocuted and that you are still alive. The chances of you becoming harmed dramatically increase once you leave the cab or touch things you are not already touching inside the cab. You should remain still in the cab with your hands in your lap unless you are presented with immediate danger.

In the event you must leave the cab, you should jump as far from the equipment as possible and land with both feet touching each other. As soon as you hit the ground, keep jumping with both feet together until you are clear of the danger.

Tacodriver, I agree with most of what you have said except the shuffling. The less you are in contact with the ground the better, hence the continued jumping.

Below is a chart on the MSHA website of recommended distances to keep from lines according to the voltages.

MSHA.gov

 

[Lashlander]

I've seen several training videos on power line contact and they say to stay put, but if you have to leave jump as for as you can then hop like a bunny or shuffle your feet on the ground with real short steps. That way you don't get in two different voltage areas.
I've never hit a power line with a crane but what has me puzzled by all of these videos I've seen is why didn't the operator just swing away. I don't care if the wire welded itself to the line I'd be breaking off power poles for a half mile to get it away from there.

 

[thejdman04]

holy cow

 

[Legdoc]

What about the marshmallows?

 

[bobcat ron]

God awful noise that arcing makes.

 

[95zIV]

We just went through this just last friday actually. I copied a link to a article I found about it. But as it was explained to me shuffling is the safest if you must get off a vehicle. By hopping you take that much more of a chance of stumbling and having to take a step, if that happens you run the chance of shortening your lifespan to just the next few seconds.

http://www.dom.com/news/downed_lines.jsp

 

[digger242j]

We just went through this just last friday actually. I copied a link to a article I found about it. But as it was explained to me shuffling is the safest if you must get off a vehicle. By hopping you take that much more of a chance of stumbling and having to take a step, if that happens you run the chance of shortening your lifespan to just the next few seconds.

http://www.dom.com/news/downed_lines.jsp

I beg to differ.

As it's been explained to me, there's a possibility that the vehicle is "charged". If you step off the vehicle, you can become the contact point between the ground and the vehicle. That's why you jump--you never want to be in contact with both the vehicle and the ground at the same time. (Perhaps you meant that you should shuffle rather than hop once you are off the vehicle, but I didn't read it that way, and I think the distinction is important.)

As far as the shuffling, this thread is the first I'd ever heard that, but I suppose it makes sense.

 

[95zIV]

Digger,

I guess I should have made that distinction. I meant after you are on the ground shuffling seems the safer bet. I thought about adding this quote when I wrote that post but I didn't mabye this will clear things up.

This is a quote from Countryboy.

Tacodriver, I agree with most of what you have said except the shuffling. The less you are in contact with the ground the better, hence the continued jumping.

Sorry for the confusion.