Log Truck vs 7200 V
Log Truck vs 7200 V
(OP)
Log truck driver tried to throw a chain over his load and managed to throw it over a distribution line. Apparently the ground fault detection was not overly sensitive.
The driver was not injured (I assume the chain slipped out of his hands), otherwise he'd be in the running for this year's Darwin Awards.
My apologies if this has already made the rounds.
Cheers,
Dave
The driver was not injured (I assume the chain slipped out of his hands), otherwise he'd be in the running for this year's Darwin Awards.
My apologies if this has already made the rounds.
Cheers,
Dave






RE: Log Truck vs 7200 V
You KNOW that the logging company will want to salvage those logs though...
"If I had eight hours to chop down a tree, I'd spend six sharpening my axe." -- Abraham Lincoln
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RE: Log Truck vs 7200 V
Driver reported the tires caught on fire almost immediately.
RE: Log Truck vs 7200 V
Jraef, I can't resist this one-maroon is a color close to purple. This guy was a moron-but a danged lucky one.
rmw
RE: Log Truck vs 7200 V
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Log Truck vs 7200 V
Keith Cress
kcress - http://www.flaminsystems.com
RE: Log Truck vs 7200 V
It was a malapropism, something Bugs Bunny was famous for...
"If I had eight hours to chop down a tree, I'd spend six sharpening my axe." -- Abraham Lincoln
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RE: Log Truck vs 7200 V
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Log Truck vs 7200 V
More pictures:
http://tow411.yuku.com/topic/48827
"If I had eight hours to chop down a tree, I'd spend six sharpening my axe." -- Abraham Lincoln
For the best use of Eng-Tips, please click here -> FAQ731-376: Eng-Tips.com Forum Policies
RE: Log Truck vs 7200 V
Still, I think this guy must be in a class of his own.
I agree with one of the posters on that thread that jraef just posted, think of what you say to your insurance adjuster.
Is there any news anywhere regarding what it did to the neighborhoods electrical service? If it passed current long enough to set that much wood on fire, as well as burn the truck down, it must have really affected the voltage on that phase.
Notice the trailer tires aren't burnt. Suspensions for log trailers are normally rubber mounted and/or rubber bushed.
rmw
RE: Log Truck vs 7200 V
I suspect the tires were the bulk fire energy used to get those logs up and running.
I can even see the red glow out of the core of that 'log reactor'!!
Keith Cress
kcress - http://www.flaminsystems.com
RE: Log Truck vs 7200 V
I think the fire was started by one heck of a big charcoal lighter driven by 7200V. Fires started by the tires would have shown evidence of burning from the outside in, not the inside out.
rmw
RE: Log Truck vs 7200 V
As per the rear bolster tires:
Keith Cress
kcress - http://www.flaminsystems.com
RE: Log Truck vs 7200 V
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Log Truck vs 7200 V
Keith Cress
kcress - http://www.flaminsystems.com
RE: Log Truck vs 7200 V
RE: Log Truck vs 7200 V
RE: Log Truck vs 7200 V
You can see the end off the cable connected to the small hand winch on the front of the first bunk. The driver would have thrown and stepped back.That's how he survived.
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Log Truck vs 7200 V
Wish there'd been video..
Keith Cress
kcress - http://www.flaminsystems.com
RE: Log Truck vs 7200 V
I sent the link to an ex-employee of mine, a guy that is still in the trucking business and has been fairly successful at it.
His take was that the trucker had been scouting this parking place for some time while practicing his throw. A way out in a bad economy with sky-high fuel prices.
rmw
RE: Log Truck vs 7200 V
RE: Log Truck vs 7200 V
Still, the resistance across the tires must have been fairly high because the fault would have had to continue for a while it seems to cause that much damage. Unless a brief spark ignited dry grass or something else. It almost looks as though the fire started at the cab and worked backwards. Maybe a surge through the winch motor, igniting the wire insulation, then rubber hoses etc?
"If I had eight hours to chop down a tree, I'd spend six sharpening my axe." -- Abraham Lincoln
For the best use of Eng-Tips, please click here -> FAQ731-376: Eng-Tips.com Forum Policies
RE: Log Truck vs 7200 V
I don't know, but I'm guessing several minutes, at least. A 100 ohm fault impedance would be 72 amps, which probably isn't going to trip a distribution feeder ground relay.
72 A at 7200 V is about 500 kW just to put it in perspective.
I'd guess the fault impedance started pretty high, then went down as the fire progressed. But there would still be the earth return to factor in.
RE: Log Truck vs 7200 V
RE: Log Truck vs 7200 V
RE: Log Truck vs 7200 V
There isen't a best answer, just the debate.
RE: Log Truck vs 7200 V
RE: Log Truck vs 7200 V
You're right, there is no answer, only the debate.
"If I had eight hours to chop down a tree, I'd spend six sharpening my axe." -- Abraham Lincoln
For the best use of Eng-Tips, please click here -> FAQ731-376: Eng-Tips.com Forum Policies
RE: Log Truck vs 7200 V
Keith Cress
kcress - http://www.flaminsystems.com
RE: Log Truck vs 7200 V
Keith Cress
kcress - http://www.flaminsystems.com