Valley Line LRT | TransEd/Marigold | City of Edmonton

Can anyone explain why the overhead wires here (and Toronto's yet to be opened line 5, as another example) are a visual mess, while in many European cities with trams, their overhead wires look more 'clean' and simple?
 
I would suggest that both north and south 116st have separate light cycles. northbound gets 30-40 seconds of green / left turn arrow, then south bound. It will increase the whole light cycle by a bit but more vehicles will get through. as is I've seen traffic backed up all the way to Jasper and to 107ave.
 
whattheheck said:
Can anyone explain why the overhead wires here (and Toronto's yet to be opened line 5, as another example) are a visual mess, while in many European cities with trams, their overhead wires look more 'clean' and simple?
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Could be different voltages (e.g., outlets are 220V in Europe vs 100 V in North America). Places like Vancouver have their electric feed next to the tracks, which works fine if tracks don’t cross intersections. They could also create an electrocution hazard.
 
whattheheck said:
Can anyone explain why the overhead wires here (and Toronto's yet to be opened line 5, as another example) are a visual mess, while in many European cities with trams, their overhead wires look more 'clean' and simple?
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Without specific European examples, I can't fully comment, however, I suspect you're referring to the use of simple contact wire vs. catenary.
Catenary allows higher speed operation by maintaining a constant tension on the wire in all temperature conditons. It also allows greater pole spacing, and reduces the need for an electrical feeder network as the messenger cable also acts to carry and feed electricity to the contact wire.
If we compare like to like, say Frankfurt's U-Bahn to Edmonton or Toronto's Line 5, it is just as "messy".
Typically you'll see the simple contact wire on older systems where single car running is the norm, and slower speeds. Of course, there are always exceptions to the rules.
Personally, I feel that the Valley Line OCS is pretty decent looking as it is certainly more "compact" looking than the Capital and Metro Lines.
 
The_Cat said:
Could be different voltages (e.g., outlets are 220V in Europe vs 100 V in North America). Places like Vancouver have their electric feed next to the tracks, which works fine if tracks don’t cross intersections. They could also create an electrocution hazard.
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Not at all. Most streetcar/ tram/ LRT and metro systems use DC, so the incoming AC current doesn't affect the vehicles that draw DC power.
Even if you have an AC powered line, it probably isn't going to be high voltage AC and would needed to be stepped down to the operating voltage.
Main line high voltage AC electrification is certainly a whole different can of worms and that is dictated a bit by the locally available power.
 
whattheheck said:
Can anyone explain why the overhead wires here (and Toronto's yet to be opened line 5, as another example) are a visual mess, while in many European cities with trams, their overhead wires look more 'clean' and simple?
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The wires on the metro line extension to blatchford have only the 2 OCS wires, but I remember someone did a video mentioning how this slows down the trains significantly. I’d rather have faster trains and see a bit more wires than slow trains with less wires.
 
I think there could be extra slack time if the paving on 104 Avenue can be done by late September or early October. Marigold said that construction west of 124 Street will shift to the middle now that both sides of SPR are paved.
 
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J_gordo said:
The wires on the metro line extension to blatchford have only the 2 OCS wires, but I remember someone did a video mentioning how this slows down the trains significantly. I’d rather have faster trains and see a bit more wires than slow trains with less wires.
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In that case I was actually arguing that the OCS design of the Blatchford extension didn't necessarily slow the trains down. The cuves leading to NAIT/ Blatchford do the slowing down, and ultimately we don't know the speed limits beyond that because they aren't posted yet. Given the close station spacing though, and the need to crossover, speeds will be restricted by that more than the OCS design.

There are 3 main types of OCS design you'll find on electric urban transit systems.
Fixed tension contact wire, constant tension contact wire, and constant tension simple catenary.
Fixed tension contact wire is used on the HLB streetcar, Fort Edmonton Park, and previously on the trolleybus network*.
Constant tension contact wire is used on the Blatchford extension, VLSE in Downtown, and in numerous tunnel segments on the Metro and Capital Lines, and the VLSE's tunnel.
Constant tension simple catenary is used everywhere else. And yes, there is more elaborate catenary... Google New Haven triangle catenary. That stuff is a work of art.

As I mentioned in my previous post, catenary allows higher speed operation, greater pole spacing, and the messenger cable feeds power to the contact wire. Constant tension contact wire needs solutions to those features in order to support higher speeds and bigger consists. For Blatchford, this is accomplished with closer pole spacing and underground feeder cables to feed the contact wire at intermediate points. In the tunnels there are frequent steady arms supporting the contact wire and what looks like the same size cable used for the messenger cable in the catenary, but just attached to the tunnel walls and then used to feed the contact wire.

*Trolleybus OCS is another can of worms, but generally the swivel shoes used to contact the wire allow for 60-70 km/h speeds in straight sections.
 
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