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Post by Tom on Apr 17, 2024 19:58:52 GMT
I agree with bigvern - most likely Rydal Crescent in the background.
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Post by Tom on Apr 16, 2024 17:02:36 GMT
inset d is a west midlands tram by the West Bromwich Parkway ? Indeed it is, at Lodge Road. An area I know very well! The 'main' for Location C is South Harrow. Taken pre-2023 as the 'Reverse' sign for WV4 is still present. I think location B might be East Finchley - making it the odd one out.
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Post by Tom on Apr 13, 2024 8:14:31 GMT
Yes, but they weren't known as Cost Centres as such. There was always an attribution process for delays.
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Post by Tom on Apr 10, 2024 21:14:49 GMT
Several dates are under consideration, ranging from later in 2024 through to the first half of 2025. The outcome of this weekend will help influence the decision making.
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Post by Tom on Apr 10, 2024 21:12:23 GMT
The 1992 stock was ordered from BREL in 1989, the same year it was sold to a consortium of ABB of Sweden, Trafalgar House and management buyout. ABB was ASEA Brown Boveri - a joint Swedish/Swiss venture. Not all of ABB became ADtranz - only the rolling stock division. Their Västerås (Sweden) factory was always a specialist in traction systems, including motors.
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Post by Tom on Apr 10, 2024 21:08:29 GMT
No. Incompatible with the signalling system, for a start, plus has no authority to run on the main line and would need significant maintenance to do so.
Also, I think the train's owners might need to be consulted - and I understand it is currently motorless after the traction motors were loaned to LU for the TRV.
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Post by Tom on Apr 10, 2024 21:07:01 GMT
72 stock with shoes removed will be guided by engineering battery locos for power at either end. These locos are Central Line signalling compliant. It will probably operate in Eng Hours anyway, but that's the way they can round the compliance issues. It will need to work in Engineering Hours as I expect a 7 car 1972 stock train top and tailed by battery locos will likely be over length.
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Post by Tom on Apr 10, 2024 21:04:42 GMT
I presume somewhere like Debden was chosen to start this project rather than straight into White City or Leytonstone for this very reason! Interesting that nobody mentions Epping or Theydon Bois which were also commissioned on the same weekend.
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Post by Tom on Apr 9, 2024 16:49:09 GMT
C is Waterloo W&C.
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Post by Tom on Apr 5, 2024 19:05:30 GMT
I'm not a Golders Green expert but I thought it was ok for passenger moves. It might have been done out of service for a number of operational reasons, or for (believe it or not) passenger convenience, to prevent a trainload of passengers having to fight their way across to another platform.
I've known similar things happen at places like Queen's Park in the past.
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Post by Tom on Apr 4, 2024 19:19:55 GMT
I hate to say this, but the Signal Life Extension Works done between Woodford and Epping haven’t really worked wonders. The problems that have been encountered are nothing compared to what will happen if the existing obsolete components are not replaced with modern equivalents. I don't have the full details but I know it's b*ggered up Debden siding for the foreseeable The work has not done as you say. I know this because I wrote the restriction that applies to Debden siding - therefore I do have the full details.
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Post by Tom on Apr 1, 2024 13:05:17 GMT
I wonder what the signal upgrade is aiming to achieve. Is it intended to extend the equipment life indefinitely by a rolling program over the years? Yes. The idea is to move away from 'big bang' full line upgrades and back to a rolling programme of upgrades and renewals - with the aim that when a rolling stock renewal programme begins that the signalling doesn't have to be upgraded or replaced to support them.
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Post by Tom on Mar 27, 2024 19:43:38 GMT
Depends on the nature of the electrification system, but probably not.
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Post by Tom on Mar 25, 2024 17:07:11 GMT
I thought most of the work was room based (replacing obsolete electronics/kit) so hope plenty of other groups took advantage of track access The work is room based, but all three sites needed to be 'wheels free' for testing.
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Post by Tom on Mar 25, 2024 1:48:19 GMT
Hoping the closure for the 23rd March is for track replacement in the Theydon Bois-Debden area? I'm afraid not. Signalling Life Extension works at Debden, Theydon Bois and Epping. East of Loughton? If that’s the case, wouldn’t it have been better if it was a Loughton to Epping closure? Or am I missing something about why this closure extends to Woodford? It extends to Woodford as the testing associated with the change at Debden affects the signalling at Loughton.
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Post by Tom on Mar 21, 2024 22:02:32 GMT
I rather expect that some of the software folks are all over this They are. (Obviously can't say much more.)
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Post by Tom on Mar 15, 2024 20:40:49 GMT
Obviously the tamping machine can't fit inside the tunnel so therefore the TSRs west of Leytonstone will remain in place until a solution is found. More importantly, a tamping machine is no use when the sleepers are set in concrete, which is the case for a lot of the track west of Leytonstone. When 67TS went on other lines they were double manned as they didn’t have a deadman’s valve. Did they not? I remember they had the vigilance button which I always assumed connected to a deadman valve when in Coded or Slow Manual modes.
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Post by Tom on Mar 7, 2024 20:10:43 GMT
The major differences are in the hardware rather than software. There is some new functionality in the SSR version but that is to be expected as it is a much more complicated railway with differing requirements.
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Post by Tom on Mar 2, 2024 22:14:02 GMT
It sounds like having northbound fast trains skip Wembley Park would actually be a positive step in keeping the service running optimally. Perhaps all day, perhaps only in the rush hours. I'm not sure I quite follow your thinking here. The problem at the moment is that a full service is being run down one track which isn't signalled for the frequency it is handling and through one platform, where the dwell time is probably also adversely affecting throughput. I don't see how non-stopping on the Northbound would help things.
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Post by Tom on Feb 27, 2024 21:45:25 GMT
As goldenarrow says, it's a combination of the two. The auto signalling between Harrow and Wembley is probably the oldest left on LU, dating from just after the Second World War. It was generally designed for a lower frequency of trains, not all of which will have stopped at Wembley - and certainly not designed to support the full service.
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Post by Tom on Feb 21, 2024 22:11:41 GMT
Also going to be the junior partner (with Go-Ahead) in Connecting Stockholm, due to take over operation of the Stockholm Metro from 2025.
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Post by Tom on Feb 19, 2024 21:34:25 GMT
Atkins were one of the better members of the Metronet Consortium.
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Post by Tom on Feb 4, 2024 16:41:58 GMT
It basically goes back to semaphore days, and that principle continued until around the Second World War by which time there were no new semaphore installations. The scheme design for Harrow was more or less complete pre-war.
As I understood it, the push-pull frames were mechanically interlocked - Harrow certainly is! Mechanical locking was provided at the Deterflex slave frame sites for use in 'local control' mode.
Bit of an update now I've had some sleep - Using multiple levers probably reduced the amount of both ways locking at diverging junctions but then there would be a need to prevent the two (or more) signal levers being reversed at the same time - but that would probably come for free using signal to point locking.
Thinking of Hanger Lane Junction (pre 2015), it used to be that that 20 x 9 and 21 x 1.➈ but if we were to use one lever it would need to be something like 20 x (1w➈).9 ➈ which requires a degree of additional conditional locking. Not the most complicated but still more complex than the use of two levers.
Of course now we have powered points on the EB too the locking is now 20 x 9, 21 x ➈, and 9 x 10. The need to provide 21 x 1 is not necessary as 1 x ➉ therefore the locking 21 x 1 is provided indirectly via the point to point locking. Had 20 provided both routes the locking would be 20 x 9 ➈ and 9 x 10.
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Post by Tom on Feb 4, 2024 11:59:01 GMT
I mean I could have answered it along the lines of "it's an older practice where one lever was allocated per route, rather than one lever for all routes", but that would be too simple!
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Post by Tom on Feb 3, 2024 14:23:00 GMT
B is Plaistow.
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Post by Tom on Jan 20, 2024 14:36:32 GMT
Do you mean Moor Park or Croxley? (Not that there are points at either location.)
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Post by Tom on Jan 14, 2024 15:51:08 GMT
It's not the greatest - I can certainly recall entering a location and it deciding I wanted to go somewhere else, which wasn't even served by TfL services!
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Post by Tom on Jan 11, 2024 13:19:24 GMT
B is Uxbridge sidings.
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Post by Tom on Jan 10, 2024 22:22:30 GMT
Unfortunately it doesn't work like that in the real world. Some members will know I work very closely with the 4LM team, so I'll try to explain as much as I can without going into specifics... What exactly is causing the delay in commissioning this area? There are a few factors. The complexity of the area and the need to interface the CBTC system to the Jubilee Line TBTC and the Neasden Depot signalling systems are one factor. The 12 hour closure in November last year was of critical importance to test some of those interfaces and the commissioning of SMA8 was heavily reliant on the testing evidence that the closure gave. Let's be clear here - this is the most technically complex part of the project. Secondly, access is a major factor. The last train stables in Neasden depot at 0104 and the first departs at 0435. However, even if the last train finishes on time there is a need to undertake shunting within Neasden depot which at the southern end requires a working signalling system. It's often 2am before staff can start work, and in that time they need to do their work, reinstate the existing system(s) and test them all ready for the start of service the next day. Testing all three systems for handback takes around an hour. So assuming staff don't get access until 0200, they need to test and be off the track by around 0410, and the testing time takes an hour, that leaves around an hour and ten minutes of useable access time. What about weekends? Doing weekend work in this area requires the suspension of both lines. This is a big ask at the best of times and coupled with the frequency of events at Wembley, means there are very few opportunities to carry out weekend testing. Even if weekends were no object, the fact that we are working with Safety Critical Software means that each software release to fix a problem found in testing (which is inevitable given the complexity of the area) needs to go through a rigorous testing regime before it can be used even with test trains. This cannot be turned around overnight, or else you get Boeing 737 Max 8 style errors. On a non-safety critical (but equally life changing) level, look at the damage poorly produced software in the Post Office's Horizon system caused. So in a nutshell, the major delays are technical complexity and access to the railway to do work. None of this should be a surprise - I fully expected this section to take a long time based on those factors alone and quite frankly when I was first introduced to how the systems would interact in this area, back in September 2019, it frazzled my brain. I totally agree that focusing the Design/Assurance team on progressing work up the Met has the biggest wins and is the critical path to project completion. It does seem however that design and installation work is still progressing elsewhere. Aren't further District line SMAs ready and worth LUL/the passenger getting the benefit from ASAP? Hardware design is now largely complete and installation is progressing. Software design is still ongoing, in the agreed order, which matches the order of installation/testing progress in other SMAs. Consequently, testing (of any kind) in the remaining District SMAs has not yet commenced. There is little benefit in dropping, for example, SMA13 or 14 software design to commence design of SMA12 software, when SMA12's hardware is still being installed. So, to answer your question, no - further District line SMAs are not ready.
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Post by Tom on Jan 9, 2024 14:43:21 GMT
Briefest of answers, but (1) Yes, (2) No.
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