A-City trains

 
  steam4ian Chief Commissioner

nm39.
You are right about ac traction motors over dc but for the wrong reasons.

AC traction motors operate at just under the convertor frequency (electrical slip) and that means that all motors fed of the one invertor (all motors if the invertors are synchronised) operate at the same speed within 3-5%. this means wheel slip is not going to unload a motor or rob power from the other motors. Much like coupled wheels on a steam loco and some diesel mechanicals.

DC motors have series wound fields and the motor driving the slipping wheel set robs power from the other motors unless all the motors are connected in parallel. For a dc system is more difficult to have slip control; thankfully not impossible.

If commutation is introducing steps in torque or current there are serious problems with the motor. Loco dc traction motors are a different beast to the three or five pole motors used in hobby systems; there are equivalent to 20 to 30+ poles (count the number of commutator segments between brush centres).

The interesting fact is that maximum torque is transmitted to the rails when the wheel rim speed is about 4% greater than the rail speed. This why later generation DEs with advanced slip control can pull more than the first generation locos.  

Ian

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  rail_road_runner Station Staff

Location: Adelaide, South Australia
Busted Very Happy

4002 middle car on Strathabyn to Goolws Rd @ 835 am
on low loader and escort, he wanted whole road, bloody greedy.. lol Very Happy

http://www.flickr.com/photos/101994561@N04/9783300524/

http://www.flickr.com/photos/101994561@N04/9783111462/
  don_dunstan The Ghost of George Stephenson

Location: Adelaide proud
Cool, the second set must be nearing completion then?  What sort of a time-table are they coming over on now, one carriage per week or so?  They would have to maintain that sort of a schedule to get 22 complete sets by this time next year but maybe that's been stretched out now like the reopening of the Seaford diesel service.
  DrJames Junior Train Controller

Location: Adelaide, SA
I wasn't aware diesels would be running to Seaford - I thought that portion of the line was being used exclusively for testing of the units until electrification of the whole line was complete? not that there's any reason they can't I guess.

Also I don't think the plan was to have 22 complete electric sets by the time the line is open to Seaford - wasn't it that 3000s would be used where necessary, gradually getting phased off the line as the order of electrics was complete and had finished testing?
  don_dunstan The Ghost of George Stephenson

Location: Adelaide proud
Oh yeah, maybe I'm wrong about that - maybe the 3000's are only going to Noarlunga.  I keep getting confused about whether it's the Seaford or Noarlunga line - when the whole line is operating they'll change the name officially I suppose.  And your point about the delivery schedule is probably right but then it leaves open the question of how much longer they will need the 2000's for; maybe for much longer than projected.
  justapassenger Minister for Railways

I wasn't aware diesels would be running to Seaford - I thought that portion of the line was being used exclusively for testing of the units until electrification of the whole line was complete?
"DrJames"
That was the original plan, but only one part of things that has gone remotely close to the schedule - the civil works on the Seaford extension.

The delivery of the EMUs was supposed to start early this year (it didn't) and electrification to Lonsdale was supposed to be ready (it wasn't) for testing to begin in the middle of this year (it didn't happen until last week).

If there's nothing stopping 3000 class DMUs from servicing the magnificent Onkaparinga River bridge and new stations which are currently just gathering dust, then they may as well open all the way to Seaford, it would only be one more part of the puzzle to not go to plan. Testing of EMUs can take place at night and weekends over the whole length of the line that is available instead of just Seaford-Noarlunga, and the current DMU fleet can easily handle running the extended services if a few consists on other lines are shortened and/or the number of cars left in the depot in the weekday peak is reduced.

Also I don't think the plan was to have 22 complete electric sets by the time the line is open to Seaford - wasn't it that 3000s would be used where necessary, gradually getting phased off the line as the order of electrics was complete and had finished testing?
"DrJames"
Only about 14 units would be needed to run a full electric service based on the old timetable, more for a higher intensity timetable of course. The original plan might have been to open to Seaford with electric units only, but that plan was of course dependent on Bombardier delivering on schedule which they haven't delivered on. To stubbornly stick with that plan would be stupid when the stations have been there and ready to receive trains for over six months.


Oh yeah, maybe I'm wrong about that - maybe the 3000's are only going to Noarlunga.  I keep getting confused about whether it's the Seaford or Noarlunga line - when the whole line is operating they'll change the name officially I suppose.  And your point about the delivery schedule is probably right but then it leaves open the question of how much longer they will need the 2000's for; maybe for much longer than projected.
"don_dunstan"
Some of the department's web pages call it the Noarlunga Line, some have already been calling it the Seaford (formerly Noarlunga) line for months.

As for the 2000 class, my guess is that they will start to draw down the fleet by attrition (i.e. retire instead of repair) from early next year. Once there are three or four electric units in service, a Jumbo set can be sent to Operation Tuna Can (hallelujah!) each time an additional electric unit enters service.
  DrJames Junior Train Controller

Location: Adelaide, SA
If there's nothing stopping 3000 class DMUs from servicing the magnificent Onkaparinga River bridge and new stations which are currently just gathering dust, then they may as well open all the way to Seaford, it would only be one more part of the puzzle to not go to plan. Testing of EMUs can take place at night and weekends over the whole length of the line that is available instead of just Seaford-Noarlunga, and the current DMU fleet can easily handle running the extended services if a few consists on other lines are shortened and/or the number of cars left in the depot in the weekday peak is reduced.
justapassenger
Hopefully, the push out to November will mean DPTI opens the Seaford line up to the DMUs as you say.  After all the negative press over the past couple of weeks, they could use a win to restore some people's faith in the system.
  justapassenger Minister for Railways

Hopefully, the push out to November will mean DPTI opens the Seaford line up to the DMUs as you say.  After all the negative press over the past couple of weeks, they could use a win to restore some people's faith in the system.
"DrJames"
It would open a good opportunity for some positive publicity, maybe with free transport on offer from Seaford for the Christmas Pagaent and the Test Match*.

A big push on DMU maintenance in the last couple of weeks leading up to the full opening could enable a slightly more intense rotation of DMUs for a couple of months between the reopening and the first few EMUs entering service.

* to be held at the department's only big project which is going as planned despite some corruption issues, ironically!
  kipioneer Chief Commissioner

Location: Aberfoyle Park
It would open a good opportunity for some positive publicity, maybe with free transport on offer from Seaford for the Christmas Pagaent and the Test Match*.

A big push on DMU maintenance in the last couple of weeks leading up to the full opening could enable a slightly more intense rotation of DMUs for a couple of months between the reopening and the first few EMUs entering service.

* to be held at the department's only big project which is going as planned despite some corruption issues, ironically!
justapassenger
What corruption issues are those, justapassenger?

I believe you have completely misconstrued the Auditor General's Report if that is what you are referring to.

Buying off-contract or in the circumstances noted isn't corruption unless there are clear kick-backs to the buyer from the vendor and in this case there have probably not been any, though if you have proof of this you should really take it to the Police.

I well recall some instances of one of DPTI's predecessors buying sand and gravel needed on a building site in a country town off contract from the local merchant because the need was now, not when the contractor could deliver and any delay was likely to impact on the work at hand.

Yes, as an Auditor I noted it, and referred it on, but it was an entirely reasonable purchase in the circumstances.

I suggest what you see as corruption is simply something akin to this.
  don_dunstan The Ghost of George Stephenson

Location: Adelaide proud
I read about those corruption allegations and it seems like a bit of a teacup storm to me; although I agree that you have to persecute it vigorously whenever you find it or it will only grow.  My own experience of it while working in a government department was that it's much more difficult to identify; more along the lines of giving your friends work and/or uncontested contracts, paying elevated prices for things (because you're getting a kick-back) or refusing to report dodgey behaviour.

Anyway, it will be interesting to see how they manage the transition to an electric service - over on the Noarlunga Upgrade thread they were saying the catenary progress is flying along so hopefully testing will expand fairly quickly up to Brighton and towards the city once the re-opening takes place, giving the new trains a full work-out.
  Arelex Station Staff
  don_dunstan The Ghost of George Stephenson

Location: Adelaide proud
Thanks for posting that.  Would I be right in assuming that some of the camera angles were from evidence cameras mounted in the cabs?  I noticed on the news yesterday with regards to the story in Brisbane of the bloke who somehow got hit by an express train and survived that they appear to have permanently mounted evidence cameras on the front of Queensland trains; will that also be a feature of the A-trains?
  2001 Moderator The Snow Lord

Location: The road jump at Charlotte Pass. Paxman Valenta on two planks.
Thanks for posting that.  Would I be right in assuming that some of the camera angles were from evidence cameras mounted in the cabs?  
don_dunstan

Yes.
  justapassenger Minister for Railways

We had them retro-fitted to the 3000/3100 years ago (mounted behind the windscreen at the bottom behind the driver's controls) so I think it would be a safe assumption they will be there from day one on the A-City EMUs. They do appear to have DOO cameras pointing back from the cab on each side, again as retro-fitted to the other ones years ago.

With the vandalism problems currently being encountered when trains have to stop at the Lynton passing loop, rigging up some cameras to point sideways could help stamp out the problem.
  don_dunstan The Ghost of George Stephenson

Location: Adelaide proud
If the Driver-only operation cameras on the sides are also recording then they should at least have some evidence of what's going on.  If the Lynton loop is a problem area then it might warrant extra police attention - I'm familiar with the area having lived in Panorama years ago so it's fairly remote but at the same time it should be easy to track these scrotes down given you have to make some significant effort to get in and out.

I've noticed since the takeover of Metro Trains here in Melbourne they don't bother with graffiti as much as Connex did; maybe because they get fined if a train is withdrawn and not replaced.
  justapassenger Minister for Railways

I don't know if the DOO cameras having recording abilities. I don't think the angle would be that good, and it surely wouldn't be too hard to attach GoPro or similar POV cameras to a number of trains as part of a police surveillance operation.

DPTI posted a photo of a couple of police officers (transit division maybe? not that it matters) with dirt bikes near the loop on Facebook this week, so I suspect there is also some more covert surveillance work that's been happening as well as that visible deterrent. The area above the northern entrance to Sleeps Hill tunnel is also patrolled on a regular basis as there have been problems with rock throwing, and alleged links with hills freight bypass advocates have been looked into there.

Unless it affects the view for staff from the cab, I would rather a train stay in service with the graffiti in place until the next scheduled rotation to the depot. It's annoying, but at the end of the day it's just paint and not worth cancelling services or deferring necessary mechanical maintenance.
  hosk1956 Deputy Commissioner

Location: no where near gunzels
We had them retro-fitted to the 3000/3100 years ago (mounted behind the windscreen at the bottom behind the driver's controls) so I think it would be a safe assumption they will be there from day one on the A-City EMUs. They do appear to have DOO cameras pointing back from the cab on each side, again as retro-fitted to the other ones years ago.

With the vandalism problems currently being encountered when trains have to stop at the Lynton passing loop, rigging up some cameras to point sideways could help stamp out the problem.
justapassenger
Your a bit loose with the "years ago" time span there JAP, the external cameras were only fitted when the railcars were refurbished, so I suppose a couple of years could qualify as years ago??? They do record onto a hard drive, the side cameras only function while the doors are open and only for a few moments after they close, they are fitted for passenger safety, not vandal surveillance.

Wayne
  don_dunstan The Ghost of George Stephenson

Location: Adelaide proud
The area above the northern entrance to Sleeps Hill tunnel is also patrolled on a regular basis as there have been problems with rock throwing...
justapassenger
Sorry to derail this thread for a moment but that sort of behaviour makes me incredibly angry, regardless of whether it's a political act or not. I was on a train years ago here in Melbourne passing through Altona at night when a huge rock was thrown at a window and it was only sheer luck that nobody was seriously hurt, just showered with shards of glass.  Rock-throwers should be strapped into a moving vehicle with random rocks thrown at their heads so they can see how dangerous and terrifying it is.
  don_dunstan The Ghost of George Stephenson

Location: Adelaide proud
The Sadvertiser reported yesterday about the testing of the A-trains on the Noarlunga-Seaford extension but also mentioned the timetable for their introduction was still unclear.

Is there any information about how many sets/carriages are at the Seaford Depot now?  I'm interested to know how delivery is progressing.
  Milkomeda Chief Train Controller

At the moment there should be the complete 4001 set and 2 parts of the 4002 set at Seaford
  don_dunstan The Ghost of George Stephenson

Location: Adelaide proud
At the moment there should be the complete 4001 set and 2 parts of the 4002 set at Seaford
Milkomeda
Cool, thank-you.  Soon they'll have enough to test how a 6-car set operates.
  rail_road_runner Station Staff
  nm39 Chief Commissioner

Location: By a road taking pictures
Howdy all,
train spotted complete at Seaford doing training - 4002.
Heres some pics.
http://www.flickr.com/photos/101994561@N04/10050148233/
http://www.flickr.com/photos/101994561@N04/10050071086/
http://www.flickr.com/photos/101994561@N04/10050010234/
http://www.flickr.com/photos/101994561@N04/10050013704/
http://www.flickr.com/photos/101994561@N04/10050088206/
rail_road_runner

Please note that the two traction cars are "A" and "B" and the non traction car with the heavy transformer and other HV gear is "T" for trailer.
  rail_road_runner Station Staff

Location: Adelaide, South Australia
Please note that the two traction cars are "A" and "B" and the non traction car with the heavy transformer and other HV gear is "T" for trailer.
nm39
thanx for heads up, i'll change it.
  Adelguy84 Beginner

any news on when 4003 should start arriving?

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