Talk:Third rail
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I deleted the language that third rails use "low" voltage. The ones near me have signs that say "Danger 750 Volts." Also, new transit systems continue to be designed and built (e.g. the Los Angeles Metro) using third rail power transmission methods, so it's incorrect to say that the method is obsolete. Mbstone 01:12, 13 Oct 2003 (UTC)
750 volts is a very low voltage in comparison to overhead wires which can carry up to 25,000 volts. Perhaps it would be better to say that it has a relatively low voltage. You've deleted an awful lot of valid content which I'm putting back. G-Man 18:03, 13 Oct 2003 (UTC)
Actually, the urban legend is true and I have found actual examples from both NYC and other areas. That is why the original article that I researched called this a 'true urban legend'.
From The Straight Dope column by Cecil Adams:
Dear Cecil:
Are there any known instances of winos, derelicts and others possessing unreliable bladders meeting their Maker while peeing on the third ("hot") rail from a subway or elevated train platform? --Impatient on the Howard line, Chicago
Dear Impatient:
Not in Chicago. But I did turn up one instance in New York City, ever the pacesetter in this regard.
Marshall Houta's Where Death Delights contains the sad story of one Joseph Patrick O'Malley, a man with two unfortunate habits: heavy drinking and wandering through subway tunnels.
One morning, O'Malley's mangled body was found in a tunnel 50 yards from the nearest station. He had apparently been struck and killed by a train.
But an autopsy turned up another cause: "The burns on the head of the penis and on the thumb and forefinger were obviously electrical burns....The stream of urine had come into contact with the 600 volts of the third rail. The current had coursed up the stream to cause the burns on his body as the electricity entered it.
"In all probability, he was dead from electrocution before the train ever hit his body." Mbstone 01:47, 13 Oct 2003 (UTC)
I read the maximum voltage for a third rail is around 1500V, but I have no source for this. But in fact, the Hamburg S-Bahn (Suburban Train) runs with 1200V DC. Rabauz 01:05, 26 Sep 2004 (UTC)
I don't think there's any rule written in stone which dictates the maximum voltage for third rail power distribution, but it would seem that 1500V is a sensible upper limit. There are probably other factors to consider - Is the rail shrouded at all? (bottom-contact systems have less to worry about) How far is the live rail from other rails or the ground? And so on. The more basic systems (the British top-contact 750V third rail is just a bare metal rail sitting on insulators, for instance) could probably be considered to have lower limits for what could be considered a "safe" voltage. -- Mpk 08:46, 28 Sep 2004 (UTC)
In reference to the Milan underground, is "electric rope" what we usually call "catenary" in english? That is, an overhead wire contacted by a trolley pole or pantograph? If so, can we edit it to say this?
In reference to maximum voltage, I believe that leakage at the insulators tends to set the maximum voltage used. Remember, the third rail is sitting in a wet, possibly dirty and salty environment; not the best environment in which to try to provide good electrical insulation!
Atlant 18:57, 17 Dec 2004 (UTC)
The article referred to the "line A of Milan's underground". There is no such thing as an "A" line in Milan -- there are M1 (red line), M2 (green line) and M3 (yellow line). So I changed the sentence to mention M1 instead of A. I suppose that's correct unless the original writer wrote "A" for some specific reason. LjL 20:51, 30 Mar 2005 (UTC)
Mythbusters
"There are unverified reports that people have died as a result of urinating on the third rail, the urine stream completing an electrical circuit that results in the victim being electrocuted."
On the Mythbusters (http://dsc.discovery.com/fansites/mythbusters/mythbusters.html) TV show, they tested this as best they could (using a dummy, and urine). IIRC, the only way they could electrocute their dummy was by using a huge (1" diameter or so) stream -- urine (at the rate it leaves the body) simply doesn't form a constant stream all the way to the ground, so there's no way for the electricity to travel through it. Maybe if you got really really close.