Deleted
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Post by Deleted on May 20, 2019 18:12:24 GMT
It’s usually a relay contact that fails or the track circuits fail like today at White City but that’s looking like a point insulation from the emails I’m getting
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Tom
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Signalfel?
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Post by Tom on May 20, 2019 18:54:30 GMT
The number of signal failures on the line seems very high for a system which is just over 20 years old and doesn’t have the issue of trainstops to go wrong. What is causing it? The electronic kit dates from the mid-late 1990s. The earliest Westrace interlockings are now 25, the younger ones 21/22. The track circuits use a microporcessor which is obsolete, to the extent that LU bought the last ones made in order to try and protect themselves as best they could against obsolescence. Basically, whilst the signalling principles, cabling, and the relay based circuitry etc was designed around a 40 year life, the electronics were capable of half that, and are now life expired. |
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Post by superteacher on May 20, 2019 19:00:41 GMT
The number of signal failures on the line seems very high for a system which is just over 20 years old and doesn’t have the issue of trainstops to go wrong. What is causing it? The electronic kit dates from the mid-late 1990s. The earliest Westrace interlockings are now 25, the younger ones 21/22. The track circuits use a microporcessor which is obsolete, to the extent that LU bought the last ones made in order to try and protect themselves as best they could against obsolescence. Basically, whilst the signalling principles, cabling, and the relay based circuitry etc was designed around a 40 year life, the electronics were capable of half that, and are now life expired. Another pretty damning indictment of the 1990s upgrade! Especially when the original Victoria line ATO lasted over 40 years with far greater reliability. Do we expect a similar life expectancy with the other ATO systems? |
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Deleted
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Post by Deleted on May 20, 2019 19:27:12 GMT
Westrace is 80's technology whereas the CBTC and TBTC system again is 80's technology, Westinghouse's DTG-R as used on the Victoria Line I believe was the first to use this technology if so this is early 00's
The Central Line manager a few years ago was trying to get the SSL upgrade put on hold until the out of date equipment was renewed as most of the PLC equipment which is made by Mitsubishi is also redundant and they no longer make that version.
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Tom
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Signalfel?
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Post by Tom on May 20, 2019 19:41:45 GMT
Elements of CBTC are very much based on 1980s tech. The data comms system is pretty up to date though, and can be because it isn't making any decisions, it's just a transmission medium.
Parts of the Victoria line system are much older, the Fixed Block Processor for example started life as the Moving Block Processor for the original Jubilee Line Extension system.
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Post by jamesb on May 21, 2019 8:51:44 GMT
I was a bit puzzled by a train that I was on that appeared to be running perfectly normally, but was taken out of service (at Leytonstone) because it had developed a fault.
Are there certain situations where the computer in the driver's cab indicates a fault that obligates the driver to remove the train from service, even though the train seems to be behaving normally? Can it ever be the case that the computer is falsely indicating that the train is faulty?
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Chris M
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Post by Chris M on May 21, 2019 10:17:29 GMT
It is possible that the fault was localised to a car that you were not travelling in.
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Colin
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My preserved fire engine!
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Post by Colin on May 21, 2019 10:24:16 GMT
I was a bit puzzled by a train that I was on that appeared to be running perfectly normally, but was taken out of service (at Leytonstone) because it had developed a fault. Are there certain situations where the computer in the driver's cab indicates a fault that obligates the driver to remove the train from service, even though the train seems to be behaving normally? Absolutely! There's a whole host of safety related systems and if any of them become unavailable, the train is deemed unsafe to remain in public service. Can it ever be the case that the computer is falsely indicating that the train is faulty? Again yes, absolutely. But the default position must be that if a safety system appears to be compromised, the train is withdrawn from service. |
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Post by spsmiler on Aug 6, 2019 20:54:00 GMT
On the topic of poor reliability - albeit of the service and the trains - having just missed a train at Ealing Broadway - I was somewhat surprised to find that the next train would be in a 12 minutes! This was around 3pm today.
Maybe a train was cancelled due to no available trains? Or there was a delay, perhaps no releife driver at White City?
What was also surprising was to then see three trains arrive in quick succession.
Ultimately this did not affect my journey home as an Overground arrived at Shepherds Bush within minutes of my arrival. But that is a different story.
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Post by Dstock7080 on Aug 7, 2019 1:10:42 GMT
On the topic of poor reliability - albeit of the service and the trains - having just missed a train at Ealing Broadway - I was somewhat surprised to find that the next train would be in a 12 minutes! This was around 3pm today. Maybe a train was cancelled due to no available trains? Or there was a delay, perhaps no releife driver at White City? Off-peak M-F services from Ealing Broadway are scheduled unevenly every: 5, 5, 10, 5, 5, 10, 5, 5, 10 etc So one of the ‘10’ intervals was just 2min late ? |
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Post by countryman on Aug 10, 2019 7:25:55 GMT
On the topic of poor reliability - albeit of the service and the trains - having just missed a train at Ealing Broadway - I was somewhat surprised to find that the next train would be in a 12 minutes! This was around 3pm today. Maybe a train was cancelled due to no available trains? Or there was a delay, perhaps no releife driver at White City? Off-peak M-F services from Ealing Broadway are scheduled unevenly every: 5, 5, 10, 5, 5, 10, 5, 5, 10 etc So one of the ‘10’ intervals was just 2min late ? Very good service now, compared to when I used the line to and from school in the late 60s. In the morning from Perivale the service was 3-4 minutes (and I assume similar from Ealing Broadway), but in the afternoon, around 3.45, it was an even 6 minutes from East Acton, obviously giving a 12 minute service on each branch. |
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Post by spsmiler on Aug 10, 2019 14:31:20 GMT
On the topic of poor reliability - albeit of the service and the trains - having just missed a train at Ealing Broadway - I was somewhat surprised to find that the next train would be in a 12 minutes! This was around 3pm today. Maybe a train was cancelled due to no available trains? Or there was a delay, perhaps no releife driver at White City? Off-peak M-F services from Ealing Broadway are scheduled unevenly every: 5, 5, 10, 5, 5, 10, 5, 5, 10 etc So one of the ‘10’ intervals was just 2min late ? So, that long wait was part of the timetable! pfft! Actually, its a crazy situation that we have become so used to trains being so very frequent that a gap (between trains) similar to what we actually expected decades ago now sees us feeling as if we have been detailed to watch paint dry! Thanks for the info! btw, when I reached Shepherds Bush I only had to wait 2 minutes for an overground - this means that even if the trains at Ealing BDWY had been more frequent my overall journey would not have been any faster. |
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Post by aslefshrugged on Sept 30, 2019 19:08:09 GMT
Tucked away in the back of Traffic Circular 20 (23 Sep - 6 Oct)
Operation of test trains on Central line on night tube nights
As part of the traction upgrade to the 92TS there will be train performance testing taking place on Friday and Saturday nights from 27 September to 26 October. Trains will operate on normal signalled to a Special Timetable Notice as train 780. This train will be operating out of passenger service all night between Debden and Epping to signalled moves only. No access is required through stations. There is no change to the traction current arrangements due to night tube running these nights. Further information from the Train Test Engineers
Hmmmmmmmmm.
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Post by superteacher on Sept 30, 2019 19:10:49 GMT
Tucked away in the back of Traffic Circular 20 (23 Sep - 6 Oct)
Operation of test trains on Central line on night tube nights
As part of the traction upgrade to the 92TS there will be train performance testing taking place on Friday and Saturday nights from 27 September to 26 October. Trains will operate on normal signalled to a Special Timetable Notice as train 780. This train will be operating out of passenger service all night between Debden and Epping to signalled moves only. No access is required through stations. There is no change to the traction current arrangements due to night tube running these nights. Further information from the Train Test Engineers
Hmmmmmmmmm.
100 kph running? |
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