smallspy said:
That's you.

The balance of the world's experience is otherwise.


Precisely.

With the decision to operate the Ontario Line at 1500V dc, the die was cast - there was no way to use anything other than catenary. No matter how Metrolinx was going to spin it, there was simply no other option.

Dan
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And with higher voltages you can have smaller onboard equipment. You see this in electric vehicle platforms, companies switching to 800V architectures.
 
asher__jo said:
And with higher voltages you can have smaller onboard equipment. You see this in electric vehicle platforms, companies switching to 800V architectures.
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Not just onboard, either. With higher voltages, the distances between substations is able to be greatly increased as well, meaning that fewer are needed.

That said, that also negates one of the major advantages of using a 600V dc system as done in Toronto - the ability to directly tap into the existing lower-voltage 3-phase industrial electrical feed and directly convert it to DC for traction power, rather than needing to step-down from much higher AC voltages. (There was also the advantage of using the same 600V dc to directly power the motors, but we're long past that.)

Dan
 
44 North said:
I'd say it is. On the whole, factoring all the evidence and effects of varying weather phenomena, that OCS is less reliable than third rail. One is rigid robust and tucked away, the other is exposed elevated and inherently weaker. And it's the latter that suffers more and results in lesser reliability.
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The effects of winter weather phenomena would be a concern with OCS if it wasn't for the planned frequency of every 90 seconds. One of the major issues with OCS is ice buildup but with a high frequency service ice buildup would be negligible especially so since the plans are for driverless trains and ATO. Operationally, they will have the flexibility of just setting the trains to run around the clock during anticipated poor weather conditions to keep everything clear.
 
MovingBlock said:
Plenty of systems (e.g. Chicago L, Berlin S-Bahn, Oslo Metro, and mainline rail in Buenos Aires, South England and New York) have level crossings with third rail.

The main issue with third rail is that it cannot accommodate voltages higher than ~750V, because of its proximity to the ground. Overhead lines provide enough isolation for higher voltages.
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I agree with your direction, but it is not correct that third rail cannot be higher than 750 V DC for the reasons you stated.

A number of systems do have higher voltages . . . including BART (1000V), Hamburgs S-Bahn (1200V in the third rail sections), and Shanghai Line 17 which uses . . . 1500V DC Third Rail! https://en.wikipedia.org/wiki/Line_17_(Shanghai_Metro) - you can Google the others and confirm.

That being said, the issue with the REM was to do with snow removal from the towers on the Champlain bridge iirc. Overhead wire is definitely the preference for most modern systems (I have looked at tons of new lines over the years - third rail is probably about 30% for Metro at most and basically nonexistent for new mainline). Higher voltages are simpler with OHLE and that reduces costs, it is also much safer to work around, often performs better in inclement weather - especially compared to top contact (used in Hong Kong which gets typhoons with crazy winds, and in Stockholm which gets way harsher winters than us).

The idea that it requires larger tunnels is true, though the actual tunnel size is much less important for cost than the station size, which isn't impacted very much by OHLE compared to other factors. Santiago's new metro lines use OHLE, and all of the Spanish ones do and they have way lower costs than Toronto.

1702494967794.png


The direction things are actually seem to be going for metros are for more rigid catenary which uses a wire attached to a rail. This is basically as robust as third rail but with all the other benefits of OHLE. I've attached a picture of Rome Line C from urbanrail where you can see what this looks like - spoiler if you thinkoverhead line looks ugly you're really going to dislike this.

1702495174988.png


I'm hoping for this to be my last post here, so sayonara! It was a good solid 10 years on here!
 
With the province looking to move the Ontario Science Centre, do we expect a potential line name change? What about the change in name of the station at the Science Centre?
 
micheal_can said:
With the province looking to move the Ontario Science Centre, do we expect a potential line name change? What about the change in name of the station at the Science Centre?
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The original conceit that the line was named for its termini was bull. They named it that to remind you who is paying for it and so there's no reason to change it now.
 
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