third rail setup

Chicago is not the only transit system that does not have third rail covers. Boston's MBTA system (Red/Orange/Blue Lines) do not have their third rail covered. The reason is that in the older cars (01400/01100/0500) have unique third rail shoes that could not support a third rail cover that the newer models would take.

Adding something about New York's third rail.... subject to errors of my memory. The important date is about 1904, the opening of the Interborough Subway from City Hall to 145th Street. At this point, the underground system was separate from the Interborough elevated lines, which used top-down block shoes. That is, the shoe rode down onto the Third Rail, much like Chicago and Boston. No cover is possible. The first subway, however, used a shoe coming in from the side and resting atop the third rail, with a wooden safety board a few inches above the third rail. This is overrunning supply, not underrunning as the New York Central installed with its electrification about 1908 and Philadelphia installed on the Market-Frankford System. During the same decade, the PRR installed overrunning third rail from Manhattan Transfer (in New Jersey) to points on Long Island, protected by a board, with the shoe coming in from the side. The catch occurred where el trains mixed with subway trains. Therefore, north of the 167th Street junction on the Jerome Avenue line, the subway third rail zig-zagged into the el position, closer to the truck, so the el shoe could come down on it in the correct position. The subway shoe was made with an angle in it. When it encountered third rail in the el position, the current was picked up just a bit further "in" than in the subway position. When a southbound subway train reached the end of the el position near 167th Street, the third rail zig-zagged outwards and a bit lower, and the shoe slipped under the wooden cover.
The same would have happened at Jackson Avenue on the White Plains Road line, as el trains and subway trains used the same third rail.
When el service was abandoned on portions of the elevated structure, leaving only subway-route trains, the third rail was (gradually, I believe) moved outward to the subway position and covered.
For years, the BMT had unprotected third rail outside the tunnels. I believe the reason was the same, but I cannot say I saw the zig-zags, which would have occurred at Prospect Park, Ninth Avenue, and probably various places in the Eastern Division.
I consider Paris and Montreal rubber-tired routes an interesting alternative. There, if I am correct, the third rail is touched by horizontal guide wheels.

bellstbarn wrote:Adding something about New York's third rail.... subject to errors of my memory. The important date is about 1904, the opening of the Interborough Subway from City Hall to 145th Street. At this point, the underground system was separate from the Interborough elevated lines, which used top-down block shoes. That is, the shoe rode down onto the Third Rail, much like Chicago and Boston. No cover is possible. The first subway, however, used a shoe coming in from the side and resting atop the third rail, with a wooden safety board a few inches above the third rail. This is overrunning supply, not underrunning as the New York Central installed with its electrification about 1908 and Philadelphia installed on the Market-Frankford System. During the same decade, the PRR installed overrunning third rail from Manhattan Transfer (in New Jersey) to points on Long Island, protected by a board, with the shoe coming in from the side. The catch occurred where el trains mixed with subway trains. Therefore, north of the 167th Street junction on the Jerome Avenue line, the subway third rail zig-zagged into the el position, closer to the truck, so the el shoe could come down on it in the correct position. The subway shoe was made with an angle in it. When it encountered third rail in the el position, the current was picked up just a bit further "in" than in the subway position. When a southbound subway train reached the end of the el position near 167th Street, the third rail zig-zagged outwards and a bit lower, and the shoe slipped under the wooden cover.
The same would have happened at Jackson Avenue on the White Plains Road line, as el trains and subway trains used the same third rail.
When el service was abandoned on portions of the elevated structure, leaving only subway-route trains, the third rail was (gradually, I believe) moved outward to the subway position and covered.
For years, the BMT had unprotected third rail outside the tunnels. I believe the reason was the same, but I cannot say I saw the zig-zags, which would have occurred at Prospect Park, Ninth Avenue, and probably various places in the Eastern Division.
I consider Paris and Montreal rubber-tired routes an interesting alternative. There, if I am correct, the third rail is touched by horizontal guide wheels.

As for the rubber tired metros, here's w page with a diagram:

http://www.emdx.org/rail/metro/principeE.html

Boston shares the uncovered, overrunning third rail setup with Chicago, but no Boston cars (on either of the three subway lines -- all use different equipment) use the block type third rail shoes. They all use shoes similiar to CTA's 2200-class cars.

The introductory paragraphs from Jan 18 2006 Chicago Tribune:

CHICAGO -- A veteran Chicago Transit Authority employee was electrocuted Tuesday morning after he touched the third rail on the Green Line tracks outside the agency's headquarters, a CTA spokeswoman said.

Authorities are investigating why the 47-year-old man, who had worked at the CTA for 25 years, was on the tracks, said agency spokeswoman Noelle Gaffney.

She said he had returned from a week of sick leave and reported to work shortly after 8 a.m. Tuesday at the agency's headquarters at 567 W. Lake St., at the Clinton Street stop.

A short time later he was spotted walking across the Green Line tracks, where he came into contact with the third rail, Gaffney said.

(For the full article try a search on Google News with the words "CTA employee" or "Chicago Transit Authority.)

Have there been any other horror stories with the CTA's third rail? I remember hearing something about a kid getting zapped and being thrown back against a fence. Needless to say, the fence hurt him more than the third rail.

Not only do Boston (copied from Chicago) and Chicago share the overunning third rail. Both London Underground and the former Southern Region of British rail have it (copied in turn from Boston). Together they have a couple of thousand miles of third rail lines, many grade crossings and 110 mph running (not on LU). It was the latest in 1904 when the first line was electrified and, by the time underrunning third rail came in they had too much to change. LU as most will know also has a fourth rail return to leave the running rails for signalling.
LS

Hi, I'm new to this forum. As a former Budd employee during the 70's and 80's, now a Septoid, I worked on the 2400-2600 series cars. I asked the CTA QC inspector about the exposed third rail pick-up. He told me this was a carry-over from the original system and not likely to be changed. he explained about the sleet scraper for winter usage.
He told a story about a dog walking along the tracks peeing on the third rail. According to him the dog must have felt something because it spun around and bit the rail. He said the dog "exploded"! I've seen the Mythbusters show about peeing on electric fences which said this was unlikely to happen, so I don't know what to believe. An electric fence has low current so as to deter, not harm, the exception being high security installations. But a third rail has high voltage AND high current.
At the 69th Street yard a cop was chasing someone across the yard and they were BOTH jumping over and stepping on the third rail! Thank God it is the underrunning type.
I have a picture of CTA worker straddling the rail performing some type of maintanence. NOT ME! working under 11k cat wires is close enough for me.

MR77100 wrote:Have there been any other horror stories with the CTA's third rail? I remember hearing something about a kid getting zapped and being thrown back against a fence. Needless to say, the fence hurt him more than the third rail.

There are occasional stories about persons that may be pushed or fall from platforms onto the 3rd rail. Not pretty. Sometimes the train can stop in time before hitting someone or thing on the tracks. No place to play or be intoxicated. Some stations have a bad reputation for crime activity.

The first use of the overrunning exposed third rail in Chicago was on the intramural railway that transported fair goers around the Columbian Exposition, World's Fair in Jackson Park in 1893. Then one of the four elevated companies, the Metropolitan adopted the same system. The South Side and the Lake Street companies soon converted from steam and they too adopted the same system. The Northwestern Elevated followed suite. The design's origin is from the United Kingdom.



Among these workers on the Green line at 59th ST, check out the one kneeling next to THE RAIL. Yes, the red thing is an insulated cover the workers use, so he's protected.



Here's a real comparison photo taken from the head car on London's Underground. That's right...there are TWO third rails, one positive and one negative return, and both exposed of course.




I was going to ask you to tell which was which, but that would be too easy. So instead we'll just say that these two photos show what a difference 70 years DOESN'T MAKE. Here is the trolley block, sleet scraper assembly and third rail pick up shoe on a 4200 from the 1920s and a high performance car from the 1990s.

Photo from CERA Bul. 115

Photo Joe Testagrose/ "L".org

Besides the 150 car Budd 2200 series, the CTA also had paddle type third rail shoes on the first groups of converted PCC cars, 6201 - 6510. The major fault of the Rail KIng O gauge tinplate model is that this type of pickup was not used. Model manufacturers like the 6201-6270 PCC cars because both cars of the married pair are identical. The 6001-6200 are only identical if modeled with the original conductor's position outside, in between the married pairs. 6511 through 6720 are not identical cars because the conductor's position is only in one car.

David Harrison

The Chicago and Boston exposed third rail system with gravity-type shoes is identical to that used in the British Underground. Personally, I think it's unsafe. The British are not as litigious a society as we are and they expect people to behave responsibly. But let someone get zapped by the third rail in Chicago and let some hungry lawyer get ahold of it...

I never could understand why the "roarin Elgin" used this type of third rail for out-of-doors, ground-level trackage. What about snow and sleet storms? The NY Central chose the underruning third rail in 1906 because it could be more completely sheathed for safety and had better protection against sleeting. Even the overrunning third rail used on the LIRR and the New York Subway has some protection because of the coverboard. The hinged third rail shoes used with this type of third rail is spring-loaded to provide better down pressure and positive contact.

keyboardkat wrote:The Chicago and Boston exposed third rail system with gravity-type shoes is identical to that used in the British Underground. Personally, I think it's unsafe.

From the looks of things, CTA management doesn't agree. They could change the setup to the style NYC has - some of the cars on the Blue Line even have the paddle-style shoes necessary for underunning third rail operation - but based on the fact that Boston, London, and Chicago share the same system and are happy with it, I would say any safety improvements are negligible.

keyboardkat wrote:The British are not as litigious a society as we are and they expect people to behave responsibly. But let someone get zapped by the third rail in Chicago and let some hungry lawyer get ahold of it.

That's why there are "Caution! High voltage! Keep out!" signs everywhere on the CTA system. The only case I can think of where a plaintiff won ended up that way because the court determined signage wasn't sufficient (this particular case being somewhat infamous, involving an inebriated man who urinated on the third rail). Since then (the 1970s), signage has been placed everywhere and although a hungry lawyer may take up such a case, a smart one wouldn't because their chances of winning are minimal. Besides, cases of people getting electrocuted are actually not that common. I would estimate that more people are killed when trains just flat out run over them, not when they come in contact with the third rail. I don't think the NYCTA has solved that problem yet either.

keyboardkat wrote:I never could understand why the "roarin Elgin" used this type of third rail for out-of-doors, ground-level trackage. What about snow and sleet storms?

That's what sleet scrapers are for.

keyboardkat wrote:The NY Central chose the underruning third rail in 1906 because it could be more completely sheathed for safety and had better protection against sleeting. Even the overrunning third rail used on the LIRR and the New York Subway has some protection because of the coverboard. The hinged third rail shoes used with this type of third rail is spring-loaded to provide better down pressure and positive contact.

The Chicago/Boston/London style third rail doesn't really need to be sprung, because gravity is pulling the shoe down anyway. And in Chicago (and I would guess in London and Boston as well) both sides of both trucks on every revenue railcar have a shoe on them, so if one shoe were to lose contact, there are three more to make up for it. Important regardless for going through third rail gaps.

One follow up question from a new forum member...

When the shoe/third rail arcs...is there any potential for damaging any of the equipment? Some of the sparking/arcing can be very impressive to watch. I wonder if the car lingered too long in one spot it could weld the shoe to the third rail...

And as a side note, I wonder if any of the rats living in the subway tunnels have ever met an untimely end by contacting the third rail.

Here at SEPTA we have under running (M-F el), over rideing (BSS & Norristown-Route 100) third rail in addition to 11k catenary for the RRD trains and 600vdc trolley for street cars and trackless trolleys. On top of that we have two gauges of track, standard gauge for the RRD, BSS and Rt.100, and wide gauge for the trolleys and the M-F el. This is a result of combining several seperate systems into one. It is quite a varaity for rail fans to take in. The wide gauge tracks are 6" wider than standard gauge. It is known as Pennsylvnia Broad gauge. It was designed to keep traction companies from running freight on city street car lines. The trolley companies got around this by building or buying freight motors for all sorts of uses.