daily menu » rate the banner | guess the city | one on oneforums map | privacy policy | DMCA | news magazine | posting guidelines

Go Back   SkyscraperCity > Infrastructure and Mobility Forums > Subways and Urban Transport

Subways and Urban Transport Metros, subways, light rail, trams, buses and other local transport systems



Global Announcement

As a general reminder, please respect others and respect copyrights. Go here to familiarize yourself with our posting policy.


Reply

 
Thread Tools
Old November 28th, 2008, 10:10 PM   #3081
lightrail
Registered User
 
Join Date: May 2007
Posts: 205
Likes (Received): 16

With regard to the four rail system, as I understand it, on London Underground the negative rail is also charged at around -300volts and the positive rail is charged at +300 something volts. But on the Network Rail lines, the centre rail is not charged but grounded to the running rails so LU trains can run on the third-rail track, discharging to the 4th "dummy" rail.

Four rail systems are not unique to London. Vancouver's Skytrain operates on a four rail system, with two power rails stacked on top of each running on the outside of the track, charged in a similar fashion to London's (-330v on the negative rail and +300v on the positive rail.

Another advantage to four rail system is it keeps the running rails clear for use in track circuits.
lightrail no está en línea   Reply With Quote

Sponsored Links
Old November 29th, 2008, 02:32 AM   #3082
Tubeman
Jubilation
 
Tubeman's Avatar
 
Join Date: Sep 2002
Location: London SE15
Posts: 18,973
Likes (Received): 3272

Quote:
Originally Posted by ajw373 View Post
The reason is on a 3rd rail system the return conductor(s) are the rails which are connected to earth. Most of the London tube tunnels are metalic, so if you were to run the return current through the rails which are connected to the tunnel sections you end up with massive corrosion. (like a big battery)

So the solution is a 4th rail which is fully insulated from the running rails and hence the walls, so no corrosion issue.

As for Christmas, as a new arrival to the UK (almost 2 years) I still find it amazing that the whole public transport system in London (buses included) shuts down on Christmas day. No doubt many don't want to work, but my experiance is there will be just as many who (with appropriate pay) will work. Afterall how many in London now days are christians and celebrate Christmas as it is intended. London is the only major city I have lived in that closes down like this. Also I beleive some lines remain closed for a few days after too, same too with mainline trains. Appaling actually and a shows further why this country is so messed up and behind the rest of the world.
We used to run Christmas day and it was wound up in the 1980's due to lack of patronage. I think it's ok... people just travel to family on Christmas Eve and come back Boxing Day... It actually gives Christmas day a nice bit of sanctity and peace (although I'm biased because my dad's house backs onto the District Line). NR shuts down Boxing day too.

Staffing isn't a problem, there's enough people who don't care, or in the case of some Muslim staff refuse to not work on Christmas Day and are told to report to head office. We don't have any variable pay rates for bank holidays though, so people just don't lose an Annual leave day if they work Xmas day (every other staff member loses a day out of their allocation).

I certainly baulk at you notion that it shows how 'backwards' we are in the UK... It's one of very few traditions left.
Tubeman no está en línea   Reply With Quote
Old November 29th, 2008, 02:34 AM   #3083
Tubeman
Jubilation
 
Tubeman's Avatar
 
Join Date: Sep 2002
Location: London SE15
Posts: 18,973
Likes (Received): 3272

Quote:
Originally Posted by lightrail View Post
With regard to the four rail system, as I understand it, on London Underground the negative rail is also charged at around -300volts and the positive rail is charged at +300 something volts. But on the Network Rail lines, the centre rail is not charged but grounded to the running rails so LU trains can run on the third-rail track, discharging to the 4th "dummy" rail.

Four rail systems are not unique to London. Vancouver's Skytrain operates on a four rail system, with two power rails stacked on top of each running on the outside of the track, charged in a similar fashion to London's (-330v on the negative rail and +300v on the positive rail.

Another advantage to four rail system is it keeps the running rails clear for use in track circuits.
LU Positive = +420V, Negative = -210V, giving a total PD of 630V

NR = approx +700V returned by the running rail
Tubeman no está en línea   Reply With Quote
Old November 29th, 2008, 03:10 AM   #3084
sotonsi
Registered User
 
Join Date: Feb 2007
Posts: 5,563

Quote:
Originally Posted by ajw373 View Post
Afterall how many in London now days are christians and celebrate Christmas as it is intended. London is the only major city I have lived in that closes down like this. Also I beleive some lines remain closed for a few days after too, same too with mainline trains. Appaling actually and a shows further why this country is so messed up and behind the rest of the world.
About 10% - a higher percentage than the rest of the country than the rest of the country. Add to that probably 75+% who celebrate it as a secular traditional festival, maybe with a nod to the religious bits of it.
Quote:
Originally Posted by Tubeman View Post
We used to run Christmas day and it was wound up in the 1980's due to lack of patronage.
as Christmas in the UK has lost much of it's religious image and became a commercialised secular festival more people celebrate it in bigger ways.
Quote:
I think it's ok... people just travel to family on Christmas Eve and come back Boxing Day... It actually gives Christmas day a nice bit of sanctity and peace (although I'm biased because my dad's house backs onto the District Line). NR shuts down Boxing day too.
Indeed, it's most civilised to shut down for a day. Breaking our hectic lives for one day.
Quote:
Staffing isn't a problem, there's enough people who don't care, or in the case of some Muslim staff refuse to not work on Christmas Day and are told to report to head office.
Very odd on the Muslims - though they don't have Christmas as celebrating Immanuel, they do believe in the Virgin Birth - which is more than most people who have the day off. I guess they'd rather have the leave for Eid or something. Is there enough staff to run a Sunday service on Christmas Day? I don't think there would be. Being given the choice of working on Christmas Day is far better than many places which close completely on Christmas Day where you have to take it off. Many force you to take three days leave as they close at lunch on the 24th and open again on the 2nd and most that aren't retail or catering would close for Christmas and Boxing Day.

I'd also think that removing the Christmas Day break (as well as getting Bob Crowe to call a strike) would put the all night service on New Years at risk.
Quote:
I certainly baulk at you notion that it shows how 'backwards' we are in the UK... It's one of very few traditions left.
I agree: it's backward to decide that we should get rid of tradition for profit. The nation goes quiet for a week, and near silent for a day when the nights are long and days are short, dull, cold and depressing. It's probably more productive to have it, even ignoring the massive amount spent on the feast and on presents - purely for morale terms.
sotonsi no está en línea   Reply With Quote
Old November 29th, 2008, 08:49 AM   #3085
jarbury
Resident Planner
 
jarbury's Avatar
 
Join Date: Aug 2007
Location: Auckland
Posts: 3,795
Likes (Received): 24

Auckland runs its buses on Christmas Day.... on a Sunday timetable. Plus a lot of the buses are actually free on that one day of the year. What's traffic like throughout the city on Xmas Day because there is no public transport running?
__________________
All opinions are my own and not my employer's (or anyone else's).
jarbury no está en línea   Reply With Quote
Old November 29th, 2008, 12:14 PM   #3086
ajw373
Registered User
 
Join Date: Oct 2007
Posts: 1,249
Likes (Received): 48

Quote:
Originally Posted by Tubeman View Post
We used to run Christmas day and it was wound up in the 1980's due to lack of patronage. I think it's ok... people just travel to family on Christmas Eve and come back Boxing Day... It actually gives Christmas day a nice bit of sanctity and peace (although I'm biased because my dad's house backs onto the District Line). NR shuts down Boxing day too.

Staffing isn't a problem, there's enough people who don't care, or in the case of some Muslim staff refuse to not work on Christmas Day and are told to report to head office. We don't have any variable pay rates for bank holidays though, so people just don't lose an Annual leave day if they work Xmas day (every other staff member loses a day out of their allocation).

I certainly baulk at you notion that it shows how 'backwards' we are in the UK... It's one of very few traditions left.
I can understand the tube shutting down because it takes a whole lot of staff to operate for little return. I am more concerned that all transport shuts down, buses included. Any yes it is very backwards, same too not getting penalty rates for holidays compared to everywhere else I have lived in this world. Even my real home which is the small city of Canberra can manage to run a bus service on Christmas day.

I wonder how people in London, many who do not have cars get to their family and freinds homes on Christmas day? Likewise how do the people who are working (police, fire, hospital etc) get to work.
ajw373 no está en línea   Reply With Quote
Old November 29th, 2008, 12:15 PM   #3087
ajw373
Registered User
 
Join Date: Oct 2007
Posts: 1,249
Likes (Received): 48

Quote:
Originally Posted by jarbury View Post
Auckland runs its buses on Christmas Day.... on a Sunday timetable. Plus a lot of the buses are actually free on that one day of the year. What's traffic like throughout the city on Xmas Day because there is no public transport running?
It is as quiet in central London at least because a great percentage of people do not have cars.
ajw373 no está en línea   Reply With Quote
Old November 29th, 2008, 12:56 PM   #3088
Tubeman
Jubilation
 
Tubeman's Avatar
 
Join Date: Sep 2002
Location: London SE15
Posts: 18,973
Likes (Received): 3272

Quote:
Originally Posted by sotonsi View Post
Very odd on the Muslims - though they don't have Christmas as celebrating Immanuel, they do believe in the Virgin Birth - which is more than most people who have the day off. I guess they'd rather have the leave for Eid or something.
Note I said some, there's only a handful who insist on working (Issa is a Muslim prophet too as you note)... So no there aren't enough to run the railway, but if it was thrown open with a bit of an incentive then I guess you'd get enough. New Year's Eve all night running is always oversubscribed.
Tubeman no está en línea   Reply With Quote
Old November 29th, 2008, 01:02 PM   #3089
Tubeman
Jubilation
 
Tubeman's Avatar
 
Join Date: Sep 2002
Location: London SE15
Posts: 18,973
Likes (Received): 3272

Quote:
Originally Posted by ajw373 View Post
I can understand the tube shutting down because it takes a whole lot of staff to operate for little return. I am more concerned that all transport shuts down, buses included. Any yes it is very backwards, same too not getting penalty rates for holidays compared to everywhere else I have lived in this world. Even my real home which is the small city of Canberra can manage to run a bus service on Christmas day.

I wonder how people in London, many who do not have cars get to their family and freinds homes on Christmas day? Likewise how do the people who are working (police, fire, hospital etc) get to work.
People who work drive, if they don't drive their organisation would get them a taxi I presume. We have LU workers finishing early Christmas morning, taxis are provided to get them home. I've lived in London all my life and don't drive... Christmas day is fine. If I am staying elsewhere I just get there Christmas Eve and come back Boxing Day, but usually it's just me and the other half alone in our flat totally undisturbed on the only day of the year we're both guaranteed to be off... It's bliss.

It's civilised not backwards. If someone really can't either arrange a lift or a taxi on Christmas day I suggest they haven't got anyone who actually wants to see them... They should stay indoors
Tubeman no está en línea   Reply With Quote
Old November 29th, 2008, 10:54 PM   #3090
Acemcbuller
Lifelong Londoner
 
Acemcbuller's Avatar
 
Join Date: Dec 2006
Location: London
Posts: 204
Likes (Received): 0

Hi Tubeman

A silly question but maybe you'll indulge me. You're not a stations bod but maybe you've got an idea what the codes for cleaners are?! It just intrigues me to hear the public address system being used to ask cleaners to attend a "code 2"! I guess its done to avoid describing the bodily fluid that's appeared on the floor!

James
Acemcbuller no está en línea   Reply With Quote
Old November 30th, 2008, 01:13 PM   #3091
Tubeman
Jubilation
 
Tubeman's Avatar
 
Join Date: Sep 2002
Location: London SE15
Posts: 18,973
Likes (Received): 3272

Quote:
Originally Posted by Acemcbuller View Post
Hi Tubeman

A silly question but maybe you'll indulge me. You're not a stations bod but maybe you've got an idea what the codes for cleaners are?! It just intrigues me to hear the public address system being used to ask cleaners to attend a "code 2"! I guess its done to avoid describing the bodily fluid that's appeared on the floor!

James
I don't know, but I'd wager it's probably puke
Tubeman no está en línea   Reply With Quote
Old November 30th, 2008, 05:04 PM   #3092
zfreeman
Registered User
 
zfreeman's Avatar
 
Join Date: Jun 2007
Location: Cork City, formally SY,UK/LDN,UK and CT,SA
Posts: 739
Likes (Received): 1

I remember once hearing a tannoy message regarding this. It went something like this:

"Could the contract cleaner please come to the end of platform 2, to give the individual a mop and bucket to clean up his urine. Yes we can see you"
zfreeman no está en línea   Reply With Quote
Old November 30th, 2008, 07:11 PM   #3093
bigbossman
Registered User
 
bigbossman's Avatar
 
Join Date: Jun 2007
Location: South East London
Posts: 3,408
Likes (Received): 4

random questions

Do you think people use the heathrow airport stations as commuter stations as there is a lot of residential land around it?

kings cross is the busiest tube station by entries/exits, what do you reckon the true busiest station in london is if you include interchange?? For me the amount of people changing lines at victoria or bank seems much larger than kings cross

cheers
bigbossman no está en línea   Reply With Quote
Old November 30th, 2008, 08:31 PM   #3094
Tubeman
Jubilation
 
Tubeman's Avatar
 
Join Date: Sep 2002
Location: London SE15
Posts: 18,973
Likes (Received): 3272

Quote:
Originally Posted by bigbossman View Post
random questions

Do you think people use the heathrow airport stations as commuter stations as there is a lot of residential land around it?

kings cross is the busiest tube station by entries/exits, what do you reckon the true busiest station in london is if you include interchange?? For me the amount of people changing lines at victoria or bank seems much larger than kings cross

cheers
I think locals to the airport use Hatton Cross station... It's too much of a palaver getting to the 'proper' airport stations as they're all inside the airport perimeter, you can't walk to them I don't think.

I think the answer to the second one is Oxford Circus
Tubeman no está en línea   Reply With Quote
Old December 1st, 2008, 01:08 AM   #3095
Rational Plan
Registered User
 
Rational Plan's Avatar
 
Join Date: Mar 2004
Location: Slough
Posts: 3,672
Likes (Received): 678

Quote:
Originally Posted by Tubeman View Post
I think locals to the airport use Hatton Cross station... It's too much of a palaver getting to the 'proper' airport stations as they're all inside the airport perimeter, you can't walk to them I don't think.

I think the answer to the second one is Oxford Circus
Not that many local people use Hatton cross to get to London. They will often change from a bus to get to Heathrow. Though Heathrow is a small site compared to other international airports, it is still huge. The main road access is a congested tunnel under the Northern Runway. With the exception of buses from the North, most buses have a convoluted journey to the terminals, hence interchanging at Hatton Cross.

The only major residential areas that are close to the airport are to the East and they are already served by the Piccadilly line. For nearly everyone else their own local train or tube station is much closer than Heathrow.
Rational Plan no está en línea   Reply With Quote
Old December 1st, 2008, 01:17 AM   #3096
elfabyanos
Dracuna Macoides
 
elfabyanos's Avatar
 
Join Date: Jun 2006
Location: Brighton
Posts: 1,814
Likes (Received): 5

Quote:
Originally Posted by Tubeman View Post
I guess so... NR seem to have a different approach to maintenance than LU do, they'll trade 24 hour running for complete weekend shut-downs every now and then whereas LU seems to prefer providing a service 364 days a year with a nightly engineering shut-down. In general our assets are in a worse state than NR, but maybe when the entire SSR has been resignalled and the track replaced the maintenance frequency can be reduced?
Also apart from the central section thameslink travel over routes with four tracking, or possible diversionary routes.

Thaniks for the link iampuking
elfabyanos no está en línea   Reply With Quote
Old December 3rd, 2008, 11:33 PM   #3097
bigbossman
Registered User
 
bigbossman's Avatar
 
Join Date: Jun 2007
Location: South East London
Posts: 3,408
Likes (Received): 4

Tubeman, had an interesting trip to oxford this week travelling on the great western main line, which tbf is damn fast and for all it's documented faults thought had a nice service, oxford-london in under an hour. But they have to electrify it, the place i stayed in was right by the station and the noise those damn deisel trains made at 5 in the morning is horrendous, do you know why this line was never fully electrified, at least to reading, oxford or bristol??

commuted to waterloo today, and the amount of people changing trains at london bridge just get to waterloo is amazing, more than stayed on to charng cross, i think at least re opening the chord to waterloo is a must for through services, even if it means cutting through the concourse... do you know what platform it would come cut through? it looked like around platform 4-5 to me.

cheers tubeman
bigbossman no está en línea   Reply With Quote
Old December 3rd, 2008, 11:34 PM   #3098
bigbossman
Registered User
 
bigbossman's Avatar
 
Join Date: Jun 2007
Location: South East London
Posts: 3,408
Likes (Received): 4

another quick one, how do tube trains and national rail stock share the same lines, running third rail and fourth rail??
bigbossman no está en línea   Reply With Quote
Old December 3rd, 2008, 11:44 PM   #3099
sarflonlad
Registered User
 
sarflonlad's Avatar
 
Join Date: May 2005
Location: London
Posts: 1,086
Likes (Received): 68

Quote:
Originally Posted by bigbossman View Post
commuted to waterloo today, and the amount of people changing trains at london bridge just get to waterloo is amazing, more than stayed on to charng cross, i think at least re opening the chord to waterloo is a must for through services, even if it means cutting through the concourse... do you know what platform it would come cut through? it looked like around platform 4-5 to me.
Waterloo East to London Bridge has always been used as an alternative W&C line - but for the south of the city/London Bridge area.

It's a nice idea to link the chord again. But you would need very frequent services to justify it - and I don't think that the SE lines could handle that. Not much bother walking a few mins to connect as you would with an LU line.
sarflonlad no está en línea   Reply With Quote
Old December 4th, 2008, 12:43 AM   #3100
bigbossman
Registered User
 
bigbossman's Avatar
 
Join Date: Jun 2007
Location: South East London
Posts: 3,408
Likes (Received): 4

Quote:
Originally Posted by sarflonlad View Post
Waterloo East to London Bridge has always been used as an alternative W&C line - but for the south of the city/London Bridge area.

It's a nice idea to link the chord again. But you would need very frequent services to justify it - and I don't think that the SE lines could handle that. Not much bother walking a few mins to connect as you would with an LU line.
no i disagree i went from london bridge to waterloo, basically alot of people who were on cannon street trains on london bridge terminators hop over to platfrom 6 to the very frequent trains into charing cross. the train was packed out for one stop then it emptied more or less at waterloo. I'd prefer all the charing cross service be diverted into waterloo and take over one of the pairs of tracks out of waterloo. i don't think charing cross is all that personally and most passengers get on at waterloo east and london bridge.
bigbossman no está en línea   Reply With Quote


Reply

Tags
london, railways, tube

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Related topics on SkyscraperCity


All times are GMT +2. The time now is 06:35 AM.


Powered by vBulletin® Version 3.8.11 Beta 4
Copyright ©2000 - 2018, vBulletin Solutions Inc.
Feedback Buttons provided by Advanced Post Thanks / Like (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.

vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.

SkyscraperCity ☆ In Urbanity We trust ☆ about us | privacy policy | DMCA policy

tech management by Sysprosium