Sure milking this one Ghery..... Derek ----- Original Message ----- From: "Pettit, Ghery" <[email protected]> To: "Kunde, Brian" <[email protected]>; "Tarver, Peter" <[email protected]>; "John Woodgate" <[email protected]>; <[email protected]> Sent: Tuesday, December 11, 2007 3:39 PM Subject: RE: stray voltage ??? Thinker???
>A good Faraday cage is completely sealed. Encasing a cow in one doesn't > sound like a good idea to me. Where's all that cow exhaust going to go? > :-) > > Oh, we're getting off topic here in a hurry! > > Ghery > > > -----Original Message----- > From: [email protected] [mailto:[email protected]] On Behalf Of Kunde, > Brian > Sent: Tuesday, December 11, 2007 1:35 PM > To: Tarver, Peter; John Woodgate; [email protected] > Subject: RE: stray voltage ??? Thinker??? > > This thread makes me think of that woman who claimed that ambient > electromagnet fields made her sick and gave her headaches though modern > medicine could find nothing wrong with her. She ended up moving away > from the city and lined the rooms of her house with aluminum foil. When > she goes outside, she wears a bee keepers hat made with wire screen to > block the rf fields from getting to her brain. Is she a nut or could she > just be more sensitive to EMI than the average person? It is commonly > believed that animals are more sensitive to their environment, such as > all the animals knew the tsunami was going to hit in Indonesia and found > higher ground. Could cows sense the currents in the ground? If so, what > is the difference of a cow standing on the ground with stray voltages > and a bird sitting on a power line? I don't see birds complaining. LOL. > > Lightning Rods transfer electrons into the air to help neutralize the > charge between the air and ground during electrical storms. Farmers have > witnessed during storms their cows running wild in the field with plasma > forming (St. Elmo's Fire) around their horns acting like a lightning rod > (the cows don't like that). Could something like that be happening where > a cow is the conduit for electrons passing between the ground and the > air? Maybe they should make faraday cage suits for cows to protect them > from stray voltages. I wonder if there is any money in this idea? > Something to think about. > > The Other Brian > > > -----Original Message----- > From: [email protected] [mailto:[email protected]] On Behalf Of Tarver, > Peter > Sent: Tuesday, December 11, 2007 2:27 PM > To: John Woodgate; [email protected] > Subject: RE: stray voltage ??? > >> From: John Woodgate >> Sent: Tuesday, December 11, 2007 9:13 AM >> >> Tarver, Peter writes: >> >> >This is a part of the ELF/VLF debate, where contention is >> made that HV >> >power lines routed near schools and housing causes increases in the >> >incidence of cancers and other illnesses, especially in children, or >> >the power lines are routed near dairy cattle effecting their milk >> >production. >> >> I disagree; these 'stray currents' are real. > > I have made no judgmental statements about what's real or imagined. > > One of the web sites mentioned in the OP was strayvoltage.org. I > recognized this web site from several years ago and remember clearly > that their concerns centered around the issues I mentioned above and > that their concerns were primarily related to high voltage distribution, > though might have included medium voltage distribution near schools. > > Even though a court has sided with dairy farmers, the debate will > continue. > >> The alternating >> currents in the overhead conductors have mutual inductance (not much, >> but enough) with conducting (resistive) soil, and therefore voltage >> gradients are induced in the soil. Cows are astonishingly sensitive to > >> these voltage gradients, partly because of their long 'heelbase' >> (sorry!), but also due to their physiology. See IEC TS60479-3. As >> little as 25 V r.m.s. >> can kill a cow, and even very low voltages can put cows under enough >> stress to affect milk yields and general health. > > These were among the points made by strayvoltage.org. Again, I made no > judgment about the veracity of any claims, one way or the other in the > above. > >> >On-premise protection devices do not come into play and >> grounded supply >> >conductors do not exist, because primary distribution is >> >three-phase-delta. >> >> I don't know what happens in USA, but in UK all line towers are >> connected together by an overhead grounded conductor at the top of >> each tower. To what extent this affects ground currents under normal >> conditions is questionable, but it does complete a big loop: tower - >> conductor - tower - ground ---- ground - tower. And if there is a >> loop, some current is bound to flow at some time. > > Grounded supply conductor = Neutral. I don't pretend to know every > reason for running these groundING wires between towers, but I > understood they provide lightning protection by presenting lightning > with a preferential path to ground, rather than through the phase > conductors. > > > Regards, > > Peter L. 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