And before he gets a chance to say it ,No liebherr1160 its not a crane :tong LOL but it does represent my greatest worry putting these machines in the air. YouTube - Crane hits power line
I dont even have to look at Tiny ..Its a sign truck .. And yes ..its bad .. In a seminar ..we got actual (accidental)video of a guy making contct ..running a knuckle boom ..the human body burns like meat on a barbque and smokes just as bad .. No.. 3-30 pop ..and hydro seemed to take forever to show up ..
Equipment & live power lines are not a good mix Very scary situation.Notice how the electricity is arcing around each outrigger & the tires trying to get to ground.If we are working close to power lines I always call the power company and they come out and safty shield the line.I also drive a ground rod down & attach it to the chassis so the crane has a good ground.
Boss sent me to check out a job.Drywall outfit wanted to stick drywall thru a window in the back of the building.Needless to say their plans were changed....This is what I saw when I walked around back.
TEREX crawler I'm running will let you enter slew limits and such forth into the LMI and you'll never have to worry about getting close.
I went to a safety meeting a local power company put on. They actually had two poles, transformers, and unshielded power lines. They'd reverse feed the lines off the buildings 240 volt service and put 7200 volts on the lines. The guy would use a dry stick to touch the lines. Nope..it caught on fire. Made a believer out of me. Secondary lines don't bother me much, but those primary lines...KEEP me away.
:jawdrop Language alert. YouTube - Boom
That is a bad day there.....
Powerlines We do some training on occasion with one of the local utilities here in Edmonton. The Safety Rep brings along a Generator trailer and mock powerlines to demonstrate the dangers. He will use a hotdog in contact with the line to show how there is no external burns on the hotdog. But, once it is cut open all you can see is charred meat He will also have one guy sit in a forkilft while he energizes it. This is an awsome demonstration to us that if you stay in the machine...You will be safe! It is the simultaneous ground and machine contact when you step out, that will kill yah!
Always jump clear forget the 3 points of contact in a wire strike situation,a further note as the crane operator you carry the blame for any incident so if it not safe then you call it and do it a different way.
That "shielding" only protects their lines from you, not the other way around, DEMAND they shut the power off, those plastic covers on the line will not save you from anything.
This accident actually happened about 30 min from me on the far end of Ottawa.
I there is a zone around the crane that the ground may be energized....I think that is the theory as to why to stay put... STUDY GUIDE ELECTRICAL SAFETY HAZARDS AWARENESS Step Potential During a ground fault, current flows through the grounding system to a ground rod or some type of system ground (steel structure, guy wire) seeking a return to its source. This current flow could possibly exist in, or along the surface of the ground for quite some distance around the point where the earth becomes energized. The current will follow, as nearly as possible, the conductors supplying the fault current. Step potential is caused by the flow of fault current through the earth. The closer a person is to the ground rod or grounded device, the greater the concentration of current and the higher the voltage. The current flow creates a voltage drop as it flows through the earth's surface and a person standing with their feet apart bridges a portion of this drop thus creating a parallel path for current flow as seen in the these two illustrations in Figure 3. The wider apart a person's legs are, the larger the voltage difference across the body. Protection from the step potential hazard should be to stay in the zone of equipotential while working. Simply being alert to this hazard is the best defense. For this reason, unqualified personnel standing on the ground are cautioned to stay clear of structures. This means that a person standing near the point where fault current enters the earth may have a large potential difference from foot-to-foot. The potential difference over the same span will be less and less as the span is moved away from either the fault current entry point or the fault current return point at the source. I do know that when I was dragging electric trucks down the right away.... I had to get out off the dozer when they did hot work... electric company rules
In the first video and the pic 25c posted how did they get permits for the building being that close to lines. I was always used to 50ft. min. clearance near any 13200 or higher. Know one farmer who had to relocate his building that was half built because it was too close.
Heavy lift has it down ..Heres some additional reading http://www.penticton.ca/electrical/ElecticalSafety-HighVoltage.pdf
when I first started we were getting towards the end of all the cell tower contracts and we had to put a couple antenna structures(candelabra?) on top of the high line poles that carry big power from transformer stations. problem was, they could only shut down the power on one side of the towers, needless to say we were only about 12 feet, at the most, away from the live lines. the worst part was when the operator asked me to get something out of the crane for him, when i placed my right hand next to the door to open it i got quite the shock. (the static energy in the air charged the crane and the wonderful operator never grounded the crane)
Are you kidding me! Nobody followed grounding procedure ..on an outage on a utility permit .... like where the hell was the utility Never in my career have I ever set up in an outage with out having the utility grounding out the machine ..prior to the outrigger's being deployed ...In fact once the crane was parked in the intended position ..Id get yanked or the permit would have been pulled If i or anyone else did anything before they signed of ..
Here's another reason to stay away from a crane or anything else with tires if it comes in contact with high power lines. http://www.msha.gov/Accident_Prevention/tips/tireheating.asp I'd heard about this today, where a tire can catch fire, internally, from the grounding arc of an accidential contact like this. What's truely frightening is that it can appear normal on the outside for hours on end before the heat and pressure inside cause it to blow up.