question about 3rd rail(Please read before locking)

[6 Lexington Ave]

So, I'm curious: what exactly is the purpose of this cover? I know that the third rail is top contact, but the cover seems too flimsy to offer any kind of protection, especially from the weather. It seems that snow/rain can easily get on it. I know of other systems with top contact third rail without any kind of cover.

[Dan05979]

It needs to be covered for workers or any type of emergency rescues. And its not flimsy. That's heavy duty fiber glass there.

[6 Lexington Ave]

It needs to be covered for workers or any type of emergency rescues. And its not flimsy. That's heavy duty fiber glass there.

It seems like wood in some places.

[RTOMan]

It seems like wood in some places.

 

It is but the idea is the same....

[Kamen Rider]

It seems like wood in some places.

Cause it was wood. The fiberglass is more recent.

[Eric B]

It's not meant to hold a lot of weight, but if one were to trip and land on it, it would certainly offer more protection than falling directly onto the rail.

[overclocked]

I've seen workers fully standing on it, regardless that the 3rd rail was live. 

[m7zanr160s]

I've seen workers fully standing on it, regardless that the 3rd rail was live. 

 

I've wondered that. I've seen LIRR track workers sit on it. It does bend a little.

[Amtrak7]

CTA doesn't use any form of covers, their third rail is bare top contact. See this link:

 

http://commons.wikimedia.org/wiki/File:CTA_third_rail_contact_shoe.jpg

 

For some reason I get an error when I try to embed the image.

[SubwayGuy]

It's to protect the third rail primarily. For example, imagine how much debris could potentially land directly on the third rail were it exposed...with garbage it would be a fire hazard...someone tosses something large and it ends up on top of the third rail and grounded elsewhere. Third rail protection board, while not making this scenario impossible, makes it much less likely (hence why track fires still occur).

 

It does also provide a little bit of safety for employees, but not a lot. It primarily indicates live third rail. In the old days, particularly in yards, there used to be exposed sections of third rail with end inclines, especially by the apron and switches. These could be extremely dangerous as there is often a lot of "spare rail" strewn about yards. A cover indicates "hey this is live".

 

Also the cover does keep the snow from accumulating on the third rail directly except in extreme cases, which is most important in a snowstorm. While some can accumulate, the frequent movement of trains (and in extreme conditions trains with scraping contact shoes) is enough to, with the protection board, keep the snow and ice from building up excessively on the 3rd rail.

[Around the Horn]

CTA doesn't use any form of covers, their third rail is bare top contact. See this link:

 

http://commons.wikimedia.org/wiki/File:CTA_third_rail_contact_shoe.jpg

 

For some reason I get an error when I try to embed the image.

CTA uses that because with their contact shoe,the cover would block contact with the rail.They use a vertical shoe over the rail,we use a horizontal paddle shoe that slides along the rail...

[pelhamlocal]

Ive seen pictures of people stand on the 3rd rail itself not just the cover even in new york, and as far as i know and the pictures show, not thing happened to them. Is it that, they shut off certain sections of third rail in yards, we trains are out of service on that specific track(a stupid and not practical idea, i know...) or is the type shoes their wear, or some weird scientifical theory thing with earth to foot contact, or something. Any ideas? thnx

[Quill Depot]

http://www.nyctransitforums.com/forums/topic/40674-third-rail-cover/?do=findComment&comment=667187

[pelhamlocal]

I know i already saw that thread, but this is what i'm talking about...

[pelhamlocal]

please disregard both my posts, sry.

 

Wait....is it just me, but didn't someone hijack this thread from me? Because i remember writing the title EXACTLY the same and posted this question:         

 

QUOTE "Ive seen pictures of people stand on the 3rd rail itself not just the cover even in new york, and as far as i know and the pictures show, not thing happened to them. Is it that, they shut off certain sections of third rail in yards, we trains are out of service on that specific track(a stupid and not practical idea, i know...) or is the type shoes their wear, or some weird scientifical theory thing with earth to foot contact, or something. Any ideas? thnx"

 

I SWEAR i remember doing this. or is someone screwing around with our site? Or again is it just me?

[6 Lexington Ave]

New question: what are those little things which look like toolboxes next to the third rail? They're not everywhere, just in some places.

[pelhamlocal]

i think they are either mini converters, relays, or fuses/circuit breakers.

[overclocked]

3rd rail heaters

[dp142]

New question: what are those little things which look like toolboxes next to the third rail? They're not everywhere, just in some places.

[dp142]

If you are talking about little boxes in between the tracks behind the 3rd rail in the yardthat are usually grey (some maybe painted red or yellow) the rectangular ones house knife switches that feed the 3rd rail, the more square ones are pull boxes where there is a dossett inside connecting the 2-2 mil cables that run under the tracks that the knife switches feed off of.

Usually you will see 2 of them close together.

 

3rd rail heaters are attached to the web of the conact rail (3rd rail) and have one lead on the negative running rail and the other on the contract rail. They are nothing more then long resistors.