Chris M
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Post by Chris M on Jul 22, 2009 21:50:04 GMT
Also, do check whether you are allowed to collect signatures for petitions (of any sort) onboard LU trains, as I've got a feeling that you've got to get permission at the very least.
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metman
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Post by metman on Jul 23, 2009 0:09:39 GMT
It's got to be given a go, that's for sure, although the whole concept is flawed. I was at Edgware Road last week and the two island platforms do not seem wide enough to cope with the large numbers of people that will transfer between them. But we need to try it to poove it doesn't work.
At the end of the day, the current system needs to be addressed and modifed to get the best out of what we have, and sadly the T-cup option does not include this!
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mrfs42
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Post by mrfs42 on Jul 23, 2009 0:09:48 GMT
I thought the whole point of it was that you couldn't go *around*.......  ;D ;D |
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mrfs42
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Post by mrfs42 on Jul 23, 2009 0:24:47 GMT
At the end of the day, the current system needs to be addressed and modifed to get the best out of what we have, and sadly the T-cup option does not include this! I'm not so sure, having spent part of the evening looking *very* carefully at the previous c. 18 months timetable notices. I've noticed that the only really new thing about the 'Extended Circle' is that it has been badged and packaged up as that. Bits of it have been running on odd occasions for a while; I may be totally wrong here, but my suspicion has been confirmed by looking through some Thameslink-related and Farringdon/KingsCrossish timetable notices (I stress this is only a guess on my behalf, nothing more) and quite a few elements of the service pattern have already been run - you know *sneakily* . Tested. In service. Who noticed? Who complained? ;D ;D Obviously I can't comment on the staffing levels/rostering as I'm not privy to that sort of information, but going back through the records I've got to hand, I wager that most of the service has already been proved in parts. What needs to be proved is that all the elements stick together and work. As a timetable afficionado I hope it does, as it is quite an elegant bit of planning. Now; can the TDs be sorted? |
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Post by Chris M on Jul 23, 2009 0:41:50 GMT
As a timetable afficionado I hope it does, as it is quite an elegant bit of planning. Now; can the TDs be sorted? With a combination of S stock and SSL resignalling, then I should think all destination description limitations will be overcome. However, C stocks will still be with us for at least several months after December at least. As for the resignalling, well I'm sure it will take place, I'm just not ready to nail my flag to the mast of the decade in which it will happen though! |
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mrfs42
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Post by mrfs42 on Jul 23, 2009 0:43:40 GMT
It is what will happen in the interregnum that will make life for the operators interesting..........
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Post by citysig on Jul 23, 2009 7:04:02 GMT
Bits of it have been running on odd occasions for a while; I may be totally wrong here, but my suspicion has been confirmed by looking through some Thameslink-related and Farringdon/KingsCrossish timetable notices (I stress this is only a guess on my behalf, nothing more) and quite a few elements of the service pattern have already been run - you know *sneakily* . Tested. In service. Who noticed? Who complained? ;D ;D Bits (tiny bits) but we all knew you could run a train the way we are going to. On the average day you will get at least 2 Inner-Rails who, after doing their Circle trip will go to Hammersmith - either due to late-running, defect or late-night timetabling. Plus you'll get Outer-Rails reversing at Edgware Road, running to Hammersmith then back for their next trip on the east - again due to late-running or defect. The King's Cross-Moorgate shutdowns were fairly easy from a controlling point of view but offered a rubbish service to the customer (it has been documented on here). As a timetable afficionado I hope it does, as it is quite an elegant bit of planning. Now; can the TDs be sorted? It is a reasonably well-thought out plan until you look at the lack of self-contained services. And when you add the crew reliefs, and take away some of the well-used reversing points, you realise that as long as it runs to time it's good. But if it goes wrong, it may take some time to recover. The TDs are a whole separate game. If the timetable works, and it ends up becoming permanant for years, some of the TD equipment simply will have to remain as is. Ex-Tower Hill eastbound for example, it is pointless spending huge wads of cash on putting in a "Hammersmith" TD. It can be displayed at Aldgate but only with operator intervention - and this cannot occur each and every time due to the way in which the system is (meant) to be operated. Maybe it will be the platform equipment which is modified to display "Hammersmith" each time a "Circle" is received. I think the odd change may be made (using previously un-used TD circuits.) Maybe produce 2 different "Edgware Road" TDs for the High St. Ken to Paddington stretch, so at least the signal operator can tell a District from a "Circle." Again, maybe simply alter the way in which "Circle" is displayed for that stretch. |
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Post by upfast on Jul 23, 2009 8:43:34 GMT
I was thinking the same. Keep the TD for the signalling equipment the same. Is it possible to change the DMI so that it says (at Embankment westbound for instance), Edgware Road via Paddington.
So does the TD Code go into the DMI which translates it for customers? Or is it done before?
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mrfs42
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Post by mrfs42 on Jul 23, 2009 9:32:54 GMT
The King's Cross-Moorgate shutdowns were fairly easy from a controlling point of view but offered a rubbish service to the customer (it has been documented on here). True, that service was nothing special. I noticed it more looking through the retimings of associated services, rather than the suspension details themselves. There have been a few interesting 'tweaks', particuarly in the District galley. EDIT: Not to mention the converse, looking at the pile of TTNs I'm just accessioning into the database of much confusion; looking at Met - City retiming due to work at Becontree. The fascination comes from the interrelated nature of disparate items, bit like weather modellling. As a timetable afficionado I hope it does, as it is quite an elegant bit of planning. Now; can the TDs be sorted? It is a reasonably well-thought out plan until you look at the lack of self-contained services. And when you add the crew reliefs, and take away some of the well-used reversing points, you realise that as long as it runs to time it's good. But if it goes wrong, it may take some time to recover. I see; so are you saying that the reduction of trains-per-hour during the slack periods (-3 top side, -1½ south side) on certain portions doesn't really give you a great advantage in SC for recovery? The TDs are a whole separate game. If the timetable works, and it ends up becoming permanant for years, some of the TD equipment simply will have to remain as is. Ex-Tower Hill eastbound for example, it is pointless spending huge wads of cash on putting in a "Hammersmith" TD. It can be displayed at Aldgate but only with operator intervention - and this cannot occur each and every time due to the way in which the system is (meant) to be operated. Maybe it will be the platform equipment which is modified to display "Hammersmith" each time a "Circle" is received. Hm. So Aldgate doesn't 'flipflop' TDs from Tower Hill, yes? Or is it a case of 'edittp' and then the trip count overruns? Would there be a similar issue with OR trains coming in from Barking? I think the odd change may be made (using previously un-used TD circuits.) Maybe produce 2 different "Edgware Road" TDs for the High St. Ken to Paddington stretch, so at least the signal operator can tell a District from a "Circle." Again, maybe simply alter the way in which "Circle" is displayed for that stretch. According to my rambling and possibly out-of-date notes there are about 8 combinations spare (without involving the 'E' permutations); changing just the DMI and keeping the TD codes the same might be easier. |
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Post by citysig on Jul 23, 2009 12:23:35 GMT
I see; so are you saying that the reduction of trains-per-hour during the slack periods (-3 top side, -1½ south side) on certain portions doesn't really give you a great advantage in SC for recovery? There is a fair bit of in-built recovery, but this is only good for "normal" run of the mill late-running. Have a decent shutdown at say, Hammersmith or on the south side of the Circle and you lose both H&C and Circle services at once. You still have the trains, but limited options of where to put them - which isn't so different from today. But we will have to be continuously aware that what action we take on the Circle at one time, will affect what happens on the H&C in the near future. Today, if we need to suspend the Circle, on one side or the other, those 7 trains are sent somewhere - Farringdon sidings, Edgware Road sidings and Hammersmith depot. Job done. When the shutdown is over, the 7 are brought back in from each of those locations. From December, if we need to lose one side of the Circle, it will be an ongoing task to keep trains away from that area. Plus, if we turn trains short and return them in the opposite direction, we have to also keep in mind that gaps will now occur in the un-related service later on if you see what I mean. Hm. So Aldgate doesn't 'flipflop' TDs from Tower Hill, yes? Or is it a case of 'edittp' and then the trip count overruns? Would there be a similar issue with OR trains coming in from Barking? The SCC computer receives each TD from Tower Hill as the correct destination - that is Upminster / Barking / Dagenham / Circle rather than just District / Circle. Tower Hill cannot send an eastbound "Hammersmith" TD for obvious reasons. The TD displayed at Aldgate is taken from the trip edit - but the code is for Aldgate site as a whole. There is no facility to split the area as far as TDs go, for example to have "Approaching Aldgate" moving to "Aldgate Station." If this was possible, then the old "Circle" TD could show for "Approaching Aldgate" with it programmed to change to "Hammersmith" at "Aldgate Station." When the new timetable comes in, it will be as it is now late evening. Trains bound for Hammersmith will be sent as, then allocate as Circle. Then when they move to Liverpool Street the next line of the trip edit can then change the TD to Hammersmith. It can be done manually at Aldgate, but this requires constant intervention from the operator - and the system is neither designed nor set up to operate in such a manner. This is where the spare / unused capacity could be used. Perhaps the current "Aldgate East" TD for the Eastbound could be used. This could be sent from Tower Hill, changing automatically to "Hammersmith" at Aldgate. |
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Post by citysig on Jul 23, 2009 12:25:45 GMT
So does the TD Code go into the DMI which translates it for customers? Or is it done before? Depending where you are, it does a bit of both, and a bit of the other. The area under the SCC receives TD codes from "outside" and then it directly updates the DMI based on its own information source. So for this, you could send one TD and have the computer translate it as something else for the purpose of the DMIs. |
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Post by upfast on Jul 23, 2009 12:36:49 GMT
So does the TD Code go into the DMI which translates it for customers? Or is it done before? Depending where you are, it does a bit of both, and a bit of the other. The area under the SCC receives TD codes from "outside" and then it directly updates the DMI based on its own information source. So for this, you could send one TD and have the computer translate it as something else for the purpose of the DMIs. Yeah, same as the Heathrow area nowadays. I was wondering how the DMI (in old fashioned lands) translated the TD Code. Such as SC staff see (for example) a ABC code as 'B', the DMI shows Barking. I'm wandering where the programming for the Barking bit is. Is it in the DMI itself or in the Tx or Rx TD units? If anyone can make sense of what I've just said! |
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Post by Harsig on Jul 23, 2009 14:29:48 GMT
This is where the spare / unused capacity could be used. Perhaps the current "Aldgate East" TD for the Eastbound could be used. This could be sent from Tower Hill, changing automatically to "Hammersmith" at Aldgate. I don't believe there is an eastbound "Aldgate East" description until the train is on the Baker St system. This issue came up last weekend when the District were reversing east to west there. The following extract from an email I received is relevant: |
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mrfs42
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Post by mrfs42 on Jul 23, 2009 14:37:49 GMT
AIUI, TD are, manually or by computer, set up as serial data, then Rx automagically converts it to parallel data; Tx transmits as serial again.
Parallel data stored as the destination. Recieved and transmitted data filtered, synchronised and stored.
In the TD units; rather than the DMI would be my outside guess.
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Post by upfast on Jul 23, 2009 14:47:25 GMT
Whitechapel is the closest TD available to Aldgate East from Earl's Court.
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mrfs42
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Post by mrfs42 on Jul 23, 2009 15:37:57 GMT
Whitechapel is the closest TD available to Aldgate East from Earl's Court. And if another part of the database of much confusion is to be believed; this has always been the case since September 1960 when Parsons Green and Putney Bridge were automated with supervision from Earls Court; the same codes were extended as programme machine working crept westwards - looking at First Supp. to TC40/60 and associated. How curious that decisions made half-a-century ago still have the capacity to affect the system! |
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Ben
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Post by Ben on Jul 23, 2009 15:42:26 GMT
With the resignalling next decade, will it be the case that any route/destination could be put up at stations for display?
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Post by citysig on Jul 23, 2009 15:43:56 GMT
I don't believe there is an eastbound "Aldgate East" description until the train is on the Baker St system. This issue came up last weekend when the District were reversing east to west there. The following extract from an email I received is relevant: Oh why didn't you say. Of course, without the old Decimal blah blah Octal twing twang... it's all perfectly clear now ;D |
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Post by citysig on Jul 23, 2009 15:45:38 GMT
With the resignalling next decade, will it be the case that any route/destination could be put up at stations for display? In theory yes (if it's more or less the same as newer systems are now.) But just as with Baker Street SCC, there are plenty of TDs that can be used within the system, but not all of them will display on the kit outside - this has to be renewed / re-programmed as well. |
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Post by 21146 on Jul 25, 2009 10:18:27 GMT
Some interesting future changes regarding destination protocols have emerged recently –
Trains starting from Hammersmith will be described as “Circle Line via Aldgate” instead of “Circle Line via Kings Cross” or “Circle Line via Liverpool Street”. At Aldgate this will change to “Circle Line to Edgware Road”. In-car DVAs are to be amended to match.
On the return trip trains will be described as “Circle Line via Aldgate”, then at Aldgate change to “Circle Line to Hammersmith” with “Hammersmith” shown on station DMIs.
Revised station line diagrams will be installed on stations to reflect the new pattern of service once its permanence is confirmed (though I thought the latter was non-negotiable!)
On S Stock there will be two lines of destination text on the cab LCD display allowing both destination and line name to be shown.
There is also a proposal to amend the existing C Stock destination blind to include the revised descriptions.
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Post by tubeprune on Jul 25, 2009 11:14:47 GMT
Whitechapel is the closest TD available to Aldgate East from Earl's Court. I'm sure that in the 60s there used to be an early morning EB District Staff train to Aldgate East, didn't there? IIRC it reversed there. |
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Post by citysig on Aug 1, 2009 8:54:17 GMT
Between myself and a couple of colleagues, we threw a couple of additional bricketts onto the New Circle BBQ. (Well with the current "summer" you have to have one somewhere ;D )
First off, a key manager's question to me reminded me of a little problem in terms of Traction Current in the Hammersmith area. The line between Shepherds Bush and Hammersmith is single-end fed from the Shepherds Bush end. Too many trains on either road, and the current will trip out on over-load. To the best of my memory from when I was a signalman at Hammersmith, this was more than 3 trains on either side - in particular on the eastbound.
Now how many times, during bits of late-running, is this going to happen? A couple of times a day never used to matter that much. In fact as a signalman it was almost a celebration that you must be doing something right in shifting trains from Hammersmith, if you got the juice to trip-out. But I wonder what will happen if the circuit breakers are constantly tripping out, all day long.
The other matter was how the service will operate once the S-stock has arrived.
The Edgware Road area is to be re-signalled (again) to take account of the new trains. Basically, you won't be able to bring any train into the middle roads if there is a train on either outside road with the station starter off. You also won't be able to signal a train into the middle roads until a train leaving Edgware Road in the same direction has fully cleared the overlap of the station starter.
So for example, a reversing train following a through eastbound won't be able to be signalled into the station until that train has its rear end beyond the pointwork to the east of the station.
On top of this, it is not known how the increased length of the trains will be accomodated. The original length of the platforms is obviously longer than at present, but then if this is utilised the signalling in the area will have to be altered even more simply to satisfy current signalling standards with regards to overlaps etc.
And even once all this is done, will a 7-car train be able to fit and reverse in the middle at Edgware Road. Let us not forget, reversing at Edgware Road is a bit of an important bit of the new timetable ;D
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Chris M
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Post by Chris M on Aug 1, 2009 11:26:09 GMT
If you're spending money on resignalling Edgware Road, how much more would it cost to completely redesign the track layout to one that didn't have these restrictions?
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mrfs42
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Post by mrfs42 on Aug 1, 2009 13:31:08 GMT
The Edgware Road area is to be re-signalled (again) to take account of the new trains. Basically, you won't be able to bring any train into the middle roads if there is a train on either outside road with the station starter off. You also won't be able to signal a train into the middle roads until a train leaving Edgware Road in the same direction has fully cleared the overlap of the station starter. So for example, a reversing train following a through eastbound won't be able to be signalled into the station until that train has its rear end beyond the pointwork to the east of the station. Something somewhere in what you've said doesn't quite make sense to me; however, I'm sure that you are perfectly correct. Why can't the approach - well, the Outer Homes signals (what are currently OP 1 and OP 36) have their controls modified to turn them into 'crawler' signals down to OP 2/3 or OP 33/34/35? Now I might be missing something quite obvious here (including the possible need for a derogation from LUL signalling principles) - but I cannot see a difference in principle between OP 1/36 being converted to something like the following signals on the Jubilee: - TH 186/100 Westminster
- TJ 158/TJ 100; TJ 157/TJ 800 London Bridge
- TL 118/TL 100 Canary Wharf
- TM 114/TM 100; TM 115 TM 2000 N. Greenwich.
Now, I've not looked in particularly strict detail at these, but the sequence of [TLX 123 RTL 125/RTL 1100], [TL 125/TL 1100] at North Greenwich seems appropriate. From what you've written, I get the clear impression that successive movements across Praed St will take anything up to ½ - 1¾ minutes longer than currently timetabled (this is only a rough guesstimate and thinking about track circuit occupancy in advance) - if so this is surely quite a retrograde step. OK, some of the extra time could be clawed back by trimming the terminal allowance at Hammersmith from 12 min as stands at present (IIRC the first Circle and Hammersmith WTT from 1989 was generally an 8 minute terminal allowance) [1]- but how thin can you shave the allowances?? On top of this, it is not known how the increased length of the trains will be accomodated. The original length of the platforms is obviously longer than at present, but then if this is utilised the signalling in the area will have to be altered even more simply to satisfy current signalling standards with regards to overlaps etc. And even once all this is done, will a 7-car train be able to fit and reverse in the middle at Edgware Road. Let us not forget, reversing at Edgware Road is a bit of an important bit of the new timetable ;D Indeed, and picking up on Chris M's point, part of the problem is the mix of electrical and mechanical interlocking at Edgware Road. I'm pretty sure looking at my notes that the locking isn't that different from when the frame was first installed. Now, overlay relay locking on top of mechanical locking isn't technically impossible, but it adds another layer of complication and a greater need to use all the contact bands driven off the lever so both sides of the interlocking (mech. vs relay) will 'know' where everything is. I'm sure that when the all-singing-and-dancing new signalling is installed then these problems can be addressed quite straightforwardly through carefully looking at target speeds on the approach. The nub of the matter is getting old kit to work with the new timetable (and allowing graceful degradation when it all goes chest-uppermost). [1] the H&C transit times and platform allowances are of particular and special relevance to what goes on at Edgware Road, and it makes interesting reading (well, to me at least) how things have changed over the years, I can go back 103 years on this particular set of data! |
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Post by citysig on Aug 1, 2009 13:36:29 GMT
If you're spending money on resignalling Edgware Road, how much more would it cost to completely redesign the track layout to one that didn't have these restrictions? Well, the last resignalling cost a few million. Ultimately signals and the associated wiring aren't cheap, but they are easier / simpler / cheaper to move / replace than structures such as platforms or track. I would imagine that the re-signalling will be done to avoid the need to move points and platforms, rather than as a part of a larger project that could actually improve things. |
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Post by citysig on Aug 1, 2009 13:50:18 GMT
Something somewhere in what you've said doesn't quite make sense to me; however, I'm sure that you are perfectly correct. Why can't the approach - well, the Outer Homes signals (what are currently OP 1 and OP 36) have their controls modified to turn them into 'crawler' signals down to OP 2/3 or OP 33/34/35? The last re-signalling altered all sorts, including the provision of speed controlled signals in place of those which weren't before if you see what I mean. OP36 and OP2/3 were two of the signals altered to speed-controlled signals. Their alteration (as well as that of OP4 and OP31 on the approaches) was deemed sufficient at the time to provide adequate protection, alongside the additional alterations to the locking. Not knowing how things are costed etc. but which would be cheaper? Altering a signal to speed control, giving it this condition and that condition, or altering the same signal to simply not clear until the preceding train is at point X. Much of what is handed to us, is, unfortunately not always based on the best option, but the cheapest / simplest option. |
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Post by citysig on Aug 1, 2009 13:59:48 GMT
Indeed, and picking up on Chris M's point, part of the problem is the mix of electrical and mechanical interlocking at Edgware Road. I'm pretty sure looking at my notes that the locking isn't that different from when the frame was first installed. Being one of the resident signalmen at the time of the re-signalling (and indeed the first to operate the new signalling on day one of it being commissioned) I can confirm that the mechanical locking was only altered slightly here and there. Most of the changes occured to the electrical locking. |
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Post by citysig on Aug 1, 2009 14:14:54 GMT
OK, some of the extra time could be clawed back by trimming the terminal allowance at Hammersmith from 12 min as stands at present (IIRC the first Circle and Hammersmith WTT from 1989 was generally an 8 minute terminal allowance) [1]- but how thin can you shave the allowances?? Remembering, of course, that one of the big selling points of the new timetable is that increased recovery at Hammersmith. It is planned (by management at least) to be one of the saving graces of the timetable, and indeed it is also the main reason why we cannot have self-contained Circle or H&C services. Mind you, this is all a couple of years off, and we haven't had the timetable in yet. But it would make a mockery of the reasons behind getting the timetable in its current form introduced. |
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mrfs42
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Post by mrfs42 on Aug 1, 2009 16:10:18 GMT
Not knowing how things are costed etc. but which would be cheaper? Altering a signal to speed control, giving it this condition and that condition, or altering the same signal to simply not clear until the preceding train is at point X. Much of what is handed to us, is, unfortunately not always based on the best option, but the cheapest / simplest option. Well; if I was costing something like this, and told to go for the cheapest option I'd just look at it from the 'not clearing until point X' - that could be achieved through simple route holding or GR/TQ relay interlinking/back contacts. If I was told to go for the most operationally suitable with money no object I'd go for speed sensing and putting ∆xxPDCRs/∆xxPDZRs in all over the place - more components, more initial outlay, more ongoing maintenance. As you know signalling kit ain't cheap! |
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Post by Ben on Aug 1, 2009 17:32:06 GMT
Surely by this point there is too much face at risk to just abandon it now? The Tcup seems to have become idolised. On principal it seems like a good simple idea; give the circle a terminus, give the hammersmith branch extra trains. But the devil is in the detail. Is it likely that the company will be cutting the nose to spite the tongue with this?
Perhaps with the SSL resignalling it'll again be possible to consider a real reorganisation of services, and solve the more intricate problems inherrent at some junctions and stations.
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