grege@gold.GVG.TEK.COM (Gregory Ebert) (02/10/90)
Several years ago I had the opportunity to witness a multi-MEGAWATT 'Jacobs ladder'. I would like to state first that this must never be repeated because it my be viewed as an act of terrorism by the authorities. About 7-8 years ago, I saw a teenager toss a bola made of copper wire and weights up into the 4KV overhead power lines. There was an instant boom-flash which caused a momentary dip an extinguished all of the streetlights for several minutes. Actually, the biggest effect was the darkness. In my perverted sense of destructive humor, I was amused. A few days later, the same individual passed by my garage and said, "Hey dude, check this out !!". He rode to the end of my street, where there are 4Kv, 16Kv, and (egad) 66KV lines. I saw him throw his bola up to the top 66KV line. One end wrapped around the top wire, and the other end swung back-and-forth above the next line below. I thought he was crazy! As I started walking back inside, I heard this enourmous buzzing growl, with popping/sizzling sounds and the famous 60hz transformer hum. A 6-8 foot arc was traveling about 10-20 feet/second down the lines toward the substation. The arc looked like it must have been 4-5 inches in diameter and had a very twisty/rapidly changing path. Unbelievable colors: blue,green,orange,purple, and white. It was so bright that, during the daytime, it caused shadows to appear in the direct sunlight. When it hit the power-pole, the metal crossarm braces caused the arc to spread to all 6 of the conductors. By this time, people were running out of their houses screaming and thinking WWIII just started. For what seemed to be an eternity, but actually only 15-20 seconds, the arc zipped along horizontally, and then finally stopped. Silence. Then sirens. Lots and lots of sirens. Police cars, and even the fire chief. People from over a mile away flocked to the scene, but only a few actually saw the whole thing. It was so powerful I swear that the earth was shaking. I'd estimate that those wires had about 500 amps apiece, making the whole event to be several megawatts. So much for those 20ma neon sign xformers !!!! To this day, you can STILL see pits in the wires !!!!