Enter the Dragon
Cajun at
Mostly Cajun is an industrial electrician and will write from time to time about close calls and other interesting events in his career. Today, he posts an entry from one of his readers who "
Saw the Dragon" I'm excerpting a bit in this quote:
Actually saw the dragon in Phoenix Az. a few moons back.
Working for a large Electrical contractor with several large projects going on simultaneously. They were all behind schedule and in penalty phase.
The company strongly urged all employees to work on a high rise Sheraton on an overtime Saturday.
It appears we were LOW bidder.
They describe the working conditions and talk about bondwire (BUSS Inter-ties - about as thick as a thumb)
...seemed almost threaded between the busses like a new garden hose unpacked by someone other than an electrician—a nice coiled spring 2-3 feet off the bottom of several sections.
And Enter the Dragon:
I place myself 2 feet from the bars about to install the huge breaker as a co-worker probably 40-50 feet away moved the bond wire a couple feet away from himself to gain temporary access to a tool on the floor.
Another electrician 100 feet away from both of us watched in horror as the cable shook back and forth until it got to me laying against 2 phases-a 480-volt blue meltdown.
My face and hands were complete 2nd degree mess. Someone slapped my t-shirt to extinguish some flames. One guy had the presence of mind to put my hands in ice water [ My dermatologist that treated me daily for 6 weeks indicated that that quick move to the ice made my injury a skin only-until you cool down you keep burning internally-we didn’t worry about my face as my predicament proved their was nothing inside to be damaged by heat]
When you get currents that large, the induced magnetic field is enough to move objects close to it. If the object happens to be another coil of wire with an equal and opposite field, they move quickly. You can see this with a simple stick welder running at 50 Amps -- imagine what it must be like running 1,000 Amps.
You have all turned on a garden hose and had the nozzle squirt around -- nominal water pressure is about 30 PSI -- Imagine the same setup with 20 times the pressure. And this current kills.
Posted by DaveH at March 24, 2005 9:21 PM