The cable he used was clx, I think. It is built almost like coax. It can have any number of pairs in it. Each individual wire inside consists of a core, insulator, Wrapped with a thin layer of foil. Some of this wire has anywhere from a single conductor to say 12 conductors in side. The very outside has a dielectric type of grease before the final sheath or insulation. Nice wire, used offshore on platforms all the time, however, it is a pain to work with. When it gets old, it is tough to peel the foil of the outside of each strand, then ofcourse, the grease sure doesn't help matters any trying to tape it or grip it. Static Electricity? I don't know, can it be created by salt water waves sloshing against the legs of the platform? Could it be parasitic charges from the generators on board? Geez, I have no idea. I know that it should definetly have a good ground since its sitting on the ocean flooring with a ton of dirt or mud holding it in place. The cable was intentionally charged and then discharged to prove to me it would hold a charge, and to prove to me it must be discharged before handling. It had to be proved as I though my leg was being pulled. I have seen formulas here saying that it is not possible, and I've seen people saying yes it was possible for these spools to hold a charge, All I know, and I have NO reason to make up short stories on spools of wire, is he proved it to me by doing it. It did seem like an interesting debate, Richard Skinner rwskinner@worldnet.att.net http://home.att.net/~rwskinner ---------- > From: Mike Keitz > To: PICLIST@MITVMA.MIT.EDU > Subject: Re: [OT] Cable retained energy, was Super Caps > Date: Tuesday, March 10, 1998 10:18 PM > > On Tue, 10 Mar 1998 21:38:31 -0500 Sean Breheny > writes: > > Jorge has mentioned that this phenomenon is > >observable when dealing with power transmission line. Power > >transmission > >line is not coaxial, is it? > > The stuff that is buried underground and used from about 2 KV up to maybe > 50 KV (e.g. for distribution to transformers in neighborhoods) is. It > has a copper or aluminum conductor at the core, thick polyethylene > insulation, then a shield made out of metal braid and conductive plastic, > and finally a black plastic outer covering. The shield is likely not > intended to normally carry current. It is connected to ground at both > ends for safety reasons. Maybe some single-phase circuits use it as the > return conductor. In any case, the coaxial construction makes it > difficult for high voltage to appear on the outside of the cable if there > is a leakage, cut or hole in the insulation. Such a circumstance will > cause the cable to arc and the fuse or circuit breaker to open. This > line is of course routinely "hipot" tested before installation by > connecting a high voltage between the center and the shield and measuring > any leakage. A big spool of it charged to many KV would indeed be > dangerous. The polyethylene insulation would prevent the charge from > leaking off for a long time as well as maybe causing a phantom "recharge" > from dielectric absorption. > > Of course such cable is intended for use at 60 Hz and is not designed for > any particular impedance. > > >I have always been told that it is single > >conductor woven cable, > > The wire strung overhead between poles is laid up of strands of aluminum > on the outside, and steel on the inside. The steel is to make it > stronger. Even at 60 Hz, there is enough of a "skin effect" to reduce > the effectiveness of the conductors in the center, so the aluminum is > outside. Except in special cases, it is bare. Please do not climb > power poles and touch the wires. You will get hurt. Really high power > lines have several cables in parallel. They are held apart in a triangle > or square arrangment to make the apparent diameter of the conductor as > large as possible. This improves the impedance and current distribution > along the line. When dealing with hundreds of km of cable, AC effects > such as phase shifts are very real at 60 Hz. > > sometimes with a hollow core with a coolent run > >through it. > > In power "substations" the conductors are sometimes placed inside much > larger outer pipes. The pipes are filled with sulfur hexafluoride gas. > SF6 is a much better insulator than air, as well as being certain to be > clean and dry, so the conductors can be in closer proximity than if they > were strung out in the open. This is rather expensive so it is done only > for extremely high voltages or where the real estate to lay out the > station with larger seperations would be even more expensive. > > I don't think the conductors in transmission systems are hollow or > actively cooled in any way. Hollow cooled wire is used to wind > generators and big motors. Hydrogen (H2) gas was used as the coolant in > one example I saw. It's both very "thin" and light (i.e. easy to move at > high velocity through small hollow passages) and absorbs heat well. It > doesn't seem that H2 gas and big electrical machines should be used near > each other. > > This is what I remember from several years ago; current practices may be > different. > > _____________________________________________________________________ > You don't need to buy Internet access to use free Internet e-mail. > Get completely free e-mail from Juno at http://www.juno.com > Or call Juno at (800) 654-JUNO [654-5866]