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TTC: Other Items (catch all)

drum118 said:
July 21
I noticed TTC has rail stack on the tracks of Lake Shore Blvd west of McD at First St. What was odd is a small section east of First St only has the rail and top coat removed while every thing east of it has everything removed down to the concrete base. Looks like this area hasn't seen any of TTC new steel beam and going to be fun trying to find space to store the beams. Work is only up to Royal York with demo taking place. East of Royal York, crews working on the overhead conversion.
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The TTC has had a big issue with stray current and electrolytic corrosion in this area for many, many years. They are going back and completely redoing a lot of the track base in this area to better insulate it.

Dan
Toronto, Ont.
 
smallspy said:
The TTC has had a big issue with stray current and electrolytic corrosion in this area for many, many years. They are going back and completely redoing a lot of the track base in this area to better insulate it.

Dan
Toronto, Ont.
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What do you mean by insulating the track? The track should be at ground potential, it is the return path for the 600VDC supply to the car.
 
doug said:
What do you mean by insulating the track? The track should be at ground potential, it is the return path for the 600VDC supply to the car.
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Actually not. I am surprised the TTC hasn't addressed this sooner, galvanic action on common ground return conductors has been known for well over a century. There must be an especially high water table there and/or particularly corrosive elements in the soil. Efforts to seriously address galvanic corrosion in pipes and rails started in the 20s. The TTC's most recent means is to wrap the rails in a neoprene or rubber like jacket, lash it to the plates with spring clips and then pour concrete around it.

Due to the electrical resistance of the steel best suited to rails, rails are not truly at ground potential unless bonded to 'earth' continuously along their length. A 'neutral return' is only one in a relative sense, even in your house wiring, which is why ground wiring and neutral wiring, even though *theoretically* at the same potential, rarely are. And the wires must never be used for a purpose not indicated for. Due to the resistance of the neutral wire being suffice at higher currents to display a voltage drop across their length to the common return point in the service panel (at which point the ground is connected to the neutrals), neutrals at the usage end can be many volts above 'ground'. This voltage differential may only typically be a couple of volts, but that's the voltage of a 'galvanic cell'....a battery! And that difference on a rail to *earth* (true ground) is more than enough to strip ions of metal from the rail, thus causing corrosion, and cause many poor electrical joints for both signal circuits and power feed.

Best I offer a reference with drawings and better thought out language:
http://www.iti.northwestern.edu/publications/barlo_zdunek/Barlo_and_Zdunek-1995-Stray Current Corrosion in Electrified Rail Systems.pdf

How bad does this get? A number of underground railway systems actually 'float' their return rail, or even do so below neutral potential, to reverse the cathodic action of electrolysis. The best known to do this is the London Underground, and the 'fourth rail' in the centre is actually nominally -210V. The third rail is +420V, both expressed relative to ground. The total potential difference is therefore 630V.
[...]
Why 4 Rails?
The London Underground uses the four rail system for two main reasons. Firstly, it was originally required by the government to limit the voltage drop along the line to 7 volts. This was intended to reduce problems caused by stray currents causing electrolysis affecting utility pipes and cables. Whilst this did not affect the street tramways, whose vehicles were not heavy current users, the currents drawn by trains could cause difficulties. The solution was either to provide heavy return cables and boosters or to use a fourth rail. The fourth rail was chosen, partly as a cheaper option and partly for signalling reasons. As direct current track circuits were to be used to control signals, an insulated return system for the traction current was an effective way of separating the two systems. Nowadays, this is not so much of a problem as all track circuits are AC. [...]
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http://www.trainweb.org/tubeprune/tractioncurr.htm

Even pipes and metal structures in contact with the earth display cathodic erosion.
Explanation here: http://www.sescocp.com/tutorial.php

Concrete ties and insulating pads are synonymous with modern electric railways nowadays, especially the higher voltage AC ones, and efforts are made to not return current at all through the rails (although some does as it's a balanced neutral conductor in a 'split transformer feed' system, used for longer runs) and centre balance neutral is never perfect, they display what's termed an 'offset voltage' especially under full loading, and the rails are 'floated' above ground save for where they are 'bonded' to earth.

The point is, 'neutral' and 'ground' rarely ever are 'absolute'...but 'earth' is usually close enough to be regarded as such if done well. Rails, no matter what measures are taken will always display some residual voltage, and with that and leakage to 'earth' comes corrosion. Insulation is the only way to address that, and even it is not absolutely effective, but helps immensely.
 
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There were a few streetcar systems that used two wires (like a trolleybus) to avoid this. Havana was a notable example, probably because the groundwater there is brackish, as was Cincinnati.
 
IRT_BMT_IND said:
There were a few streetcar systems that used two wires (like a trolleybus) to avoid this. Havana was a notable example, probably because the groundwater there is brackish, as was Cincinnati.
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Good point, although some of those double wire catenaries were triple phase feed, the third conductor still being the rail, and the phase angle between each conductor being 120 degrees. Needless to say, these would be AC systems with the attendant benefits for motor control, torque and efficiency. Junctions would be a bitch though, albeit no worse than trolley buses plus rails.

https://en.wikipedia.org/wiki/Three-phase_AC_railway_electrification

Havana was a DC system, having trouble finding a tech explanation, but note the Cincinnati reference to "ground return currents"

DC, two-wire
[...]
On DC systems, bipolar overhead lines were sometimes used to avoid galvanic corrosion of metallic parts near the railway, such as on the Chemin de fer de la Mure.

All systems with multiple overhead lines have high risk of short circuits at switches and therefore tend to be impractical in use, especially when high voltages are used or when trains run through the points at high speed.
[...]
https://en.wikipedia.org/wiki/Overhead_line#Multiple_overhead_lines

Note: " Previously used by trams when in the vicinity of Greenwich Observatory; separate from trolleybus supply." That would have been to *balance* as perfectly as possible the potential of the supply wires to ground (or earth, same in this instance).

That would be to prevent any 'earth', 'leakage' or 'spurious' currents that would be enough to throw off the magnetometers and magnetic compasses in the observatory, some of those instruments, even in those days, being extremely sensitive to currents, magnetic or electrically induced magnetic ones.
 
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Just overheard some idle chatter among TTC workers on the subway about how TTC may gave acquired land near Kipling for a new TR(?) yard. Take it all with a grain of salt - guess they maybe referring to Obico?

AoD
 
AlvinofDiaspar said:
Just overheard some idle chatter among TTC workers on the subway about how TTC may gave acquired land near Kipling for a new TR(?) yard. Take it all with a grain of salt - guess they maybe referring to Obico?

AoD
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Not just chatter.

That's the plan as I understand it.

The prelim. intent is that Obico would be the principle yard for B-D, while Greenwood would service the Relief line.

Greenwood is not currently set up to maintain the TRs

Any extension of B-D, ie the SSE would also require a move to ATC and therefore to TRs or other next-gen, ATC-equipped rolling stock.

Were the current timeline for SSE to hold (open around 2026) the desire would be to have a new yard up by then.
 
TTC is not a fan of book sharing http://www.metronews.ca/news/toronto/2017/07/24/ttc-books-on-the-transit.html?cq_ck=1500937892866

The TTC wants no part of a grassroots transit book sharing program that is popular around the world.

Thirty-five-year-old Kristyn Little and 25-year-old Danielle Sanders launched Books on the Transit in March, the Toronto chapter of a worldwide movement to leave books on transit for others to read. The two women have left at least 100 books on transit over the past few months, which include stickers that tell transit riders the novel is theirs to pick up. Books include recent bestsellers and literary classics, with offerings from authors like Joy Fielding, Tom Clancy and Harper Lee.

Similar grassroots-led programs exist in New York City, Montreal, Chicago, Boston and London, England with the support of their local transit agencies.

While regional transportation agency Metrolinx supports the initiative, the TTC does not. In an email to Metro, TTC spokesperson Brad Ross explained the transit agency's stance.

"We would prefer people, no matter how well-intentioned, not leave books on TTC property," he wrote.

"There is the very real possibility they could get turned in as lost articles or simply discarded and we cannot take on the additional task of trying to keep tabs on these items." He also encouraged TTC riders to use the city's extensive library system.

So far Metrolinx, which has co-operated with Books on the Transit, has not been overwhelmed with a library of books in its lost and found.

Little and Sanders have left books on GO trains, buses and the Union-Pearson Express, leaving them on seats and on top of automated ticket machines.

Metrolinx spokesperson Anne Marie Aikins says it's working out so far.

"People are clearly taking the books," she told Metro, adding that Metrolinx only gets a couple of the books in the lost and found each month, and that they are clearly identified by the stickers on the cover.

Aikins also said Books on the Transit fits in with the rider experience Metrolinx hopes to create.

"People want to be comfortable," she said.

Little said she's thrilled with the positive feedback they have received on their project so far, although she's disappointed that the TTC hasn't supported it.

"It's very unfortunate," she said.

"We'd love their participation and I honestly don't understand their hesitancy."
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PinkLucy said:
TTC is not a fan of book sharing http://www.metronews.ca/news/toronto/2017/07/24/ttc-books-on-the-transit.html?cq_ck=1500937892866
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I'm with Lucy on this, and it's more than just the TTC. I've heard criticism of the 'Little Borrowing Libraries' people are putting up on their front yards next to the sidewalk, some calling them "clutter"...some librarians even criticizing them as "the wrong approach". WTF? Is it superfluous to need? Perhaps, but that misses the point entirely. They are *shrines* to the concept of books and keeping them in circulation. It says a huge amount about a society, let alone the inundation of digital media in lieu of the printed word.

The TTC will have to back down on this...
"We would prefer people, no matter how well-intentioned, not leave books on TTC property," he wrote.

"There is the very real possibility they could get turned in as lost articles or simply discarded and we cannot take on the additional task of trying to keep tabs on these items." He also encouraged TTC riders to use the city's extensive library system.
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Oh well pardon me! They allow disposable newspapers rampantly discarded on the system, but can't tolerate a lasting publication?

This will go viral, as well it should.
 
steveintoronto said:
I'm with Lucy on this, and it's more than just the TTC. I've heard criticism of the 'Little Borrowing Libraries' people are putting up on their front yards next to the sidewalk, some calling them "clutter"...some librarians even criticizing them as "the wrong approach". WTF? Is it superfluous to need? Perhaps, but that misses the point entirely. They are *shrines* to the concept of books and keeping them in circulation. It says a huge amount about a society, let alone the inundation of digital media in lieu of the printed word.

The TTC will have to back down on this...
Oh well pardon me! They allow disposable newspapers rampantly discarded on the system, but can't tolerate a lasting publication?

This will go viral, as well it should.
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People who like books will find a way to have them. It's not the job of the transit agency to facilitate it on their grounds - and frankly, they allow way to much of this sort already. If you want a shrine to books, go to a library.

So you think we should add books on top of the discarded reading materials problem on TTC? Just because someone think it is a good idea doesn't mean it is one.

AoD
 
Bingo!
Book fairies want to bring Toronto riders 'back to paper'
'I just want to see people reading more,' says Sanders
By Malone Mullin, CBC News Posted: Jul 23, 2017 7:23 PM ET Last Updated: Jul 24, 2017 4:45 PM ET

When Danielle Sanders glances around on her daily ride into work, she sees heads bowed into glowing screens, thumbs tapping out messages to the void.

The whole experience strikes 25-year-old Sanders as depressing. So one day in March — rather than sigh and turn back to her own digital world — she decided to break the cycle.

Sanders co-founded Books on the Transit, a kind of chaotic, mobile library, alongside another Toronto-area bookworm, Kristyn Little.

Their mantra: Ride, read and return.

"I commute daily. People are absorbed in their phones, and I wanted to change that and revolutionize the commuter experience to bring it back to paper," Sanders said of her motivation for the project.

Sanders and Little go out on regular "book drops," leaving classics and new releases around hand-rails, on seats and just about anywhere in the station for riders to pick up.

They've got about 100 books in circulation, Little says, and each one has a sticker affixed to the cover declaring that it's to be brought home, enjoyed, and returned to a conspicuous corner of the Toronto transit system for the next rider to use.

Separately, both co-founders reached out to the international organization Books on the Move, which originated in London, U.K. and New York City.

Divisions now exist in Boston, Montreal and Los Angeles, amongst other cities worldwide.

Soon after meeting through Books on the Move, Little and Sanders launched social media pages to promote the Toronto branch.

They reached out to the transit operator Metrolinx, which Little says got on board with enthusiasm. "Our contact there even 'likes' all of our Instagram photos," Little laughed.

Books on the Transit hasn't received permission to run book drops on the TTC, but Little hopes they can expand Books on the Transit to include Toronto's busy subway and bus network.

TTC officials originally told Books on the Transit that the transit agency didn't have the resources to tackle the project and to contact them again in 2018.

In a statement to CBC Toronto on Monday morning, TTC spokesperson Stuart Green said the transit agency is not interested in participating at this time.

"We would prefer people, no matter how well-intentioned, not leave books laying around on TTC property," said Green.

"There is the very real possibility they could get turned in as lost articles or simply discarded and we cannot take on the additional task of trying to keep tabs on these items," he added. "Toronto has one of the greatest public library systems in the world that people should be encouraged to use."

Little still hopes to partner with the TTC and says Books on the Transit would take on the bulk of the work if books needed to be collected from the lost and found.

"Having books on the TTC would be huge," said Little. "A growing bookshare program would make people enjoy and look forward to their commute."

Books "bring people together in a way that a phone can't," Sanders added, pointing out that a book can be a conversation starter, a way to connect to one's transit companions.

"If you look at old photos, everyone's sitting on the train with newspapers. That was an element that was missing on my daily commute."

Eventually, the two want to see people dropping books of their own accord.

"I just want to see people reading more," said Sanders. "They're conversation starters, brain food."
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http://www.cbc.ca/news/canada/toronto/books-on-transit-1.4218270
 
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