|
|
Post by superteacher on Dec 29, 2013 17:18:18 GMT
I have been thinking about how train numbering (set numbers) have evolved over the years. I would appreciate any comments that anybody has regarding the historical aspect of train numbering, and how and why numbering systems have changed.
Central line - numbered in the 0xx and 1xx series. As far as I'm aware, this has been the case for a very long time.
Northern line - as above.
Victoria line - numbered in the 2xx series since opening. I believe that they begin with 2 to distinguish them from Northern line workings since both lines were controlled from Cobourg Street. Now that the line has its own control centre, they could, in theory, lose the 2 prefix.
District line - numbered in the 0xx and 1xx series for a long, long time!
Metropolitan line. Were numbered in the 0xx until a few years ago, but changed to 4xx to distinguish them from District line workings.
Hammersmith / Circle - numbered in the 2xx series, but I believe that this only happened from the 1960's / 70's.
Piccadilly line - numbered in the 2xx and 3xx series to distinguish them from District and Met workings.
Jubilee line -numbered in the 3xx series to distinguish them from Met and Bakerloo workings.
Waterloo and City line - numbered in the 4xx series
Bakerloo line - numbered in the 2xx series from, I believe, the time when the line ceased to run to Watford. They were, prior to this, in the 1xx series. Did the Bakerloo numbering system change because the line was controlled from the same building as the Central, and therefore wanted to distinguish them from each other?
A final general point - I'm aware that train numbers do not contain the digits 8 and 9 due to the binary nature of the programme machines. However, quite a lot of lines now use solid state computer technology, and so can presumably cope with 8's and 9's. So why not use them again?
|
|
mrfs42
71E25683904T 172E6538094T
Big Hair Day
Posts: 5,922
|
Post by mrfs42 on Dec 29, 2013 17:32:32 GMT
I have been thinking about how train numbering (set numbers) have evolved over the years. I would appreciate any comments that anybody has regarding the historical aspect of train numbering, and how and why numbering systems have changed. Are you interested in when lines renumbered into programme-machine numbers? A final general point - I'm aware that train numbers do not contain the digits 8 and 9 due to the binary nature of the programme machines. However, quite a lot of lines now use solid state computer technology, and so can presumably cope with 8's and 9's. So why not use them again? ..ummm... tradition? some circuitry [1] can't cope with 8 and 9? TTO programmes not able to cope with 8 and 9 so they would need to be individually inserted into the galley. [1] PM TD emulators, principally but also (possibly) slow-speed scanning on the Picc. |
|
roythebus
Pleased to say the restoration of BEA coach MLL738 is as complete as it can be, now restoring MLL721
Posts: 1,275
|
Post by roythebus on Dec 29, 2013 20:40:29 GMT
Reminds me of the time, possibly 1971, when there was a Bank holiday. The DR ran a Saturday service, the Met a MF service... then 2 train 71's (or whatever it was)turned up at Liverpool Street to terminate in the bay platform. The following year the DR stopped running past Edgware road on Saturdays!
On the DR 1xx numbers were usually rush hour extras that maybe only done a round trip in each of the peaks.
|
|
|
|
Post by motorman on Dec 29, 2013 21:22:50 GMT
That could probably not have been planned if one had tried!
|
|
mrfs42
71E25683904T 172E6538094T
Big Hair Day
Posts: 5,922
|
Post by mrfs42 on Dec 29, 2013 21:37:19 GMT
Yes - ISTR that 1xx were the push-ins.
|
|
|
|
Post by railtechnician on Dec 30, 2013 3:42:28 GMT
I have been thinking about how train numbering (set numbers) have evolved over the years. I would appreciate any comments that anybody has regarding the historical aspect of train numbering, and how and why numbering systems have changed. Central line - numbered in the 0xx and 1xx series. As far as I'm aware, this has been the case for a very long time. Northern line - as above. Victoria line - numbered in the 2xx series since opening. I believe that they begin with 2 to distinguish them from Northern line workings since both lines were controlled from Cobourg Street. Now that the line has its own control centre, they could, in theory, lose the 2 prefix. District line - numbered in the 0xx and 1xx series for a long, long time! Metropolitan line. Were numbered in the 0xx until a few years ago, but changed to 4xx to distinguish them from District line workings. Hammersmith / Circle - numbered in the 2xx series, but I believe that this only happened from the 1960's / 70's. Piccadilly line - numbered in the 2xx and 3xx series to distinguish them from District and Met workings. Jubilee line -numbered in the 3xx series to distinguish them from Met and Bakerloo workings. Waterloo and City line - numbered in the 4xx series Bakerloo line - numbered in the 2xx series from, I believe, the time when the line ceased to run to Watford. They were, prior to this, in the 1xx series. Did the Bakerloo numbering system change because the line was controlled from the same building as the Central, and therefore wanted to distinguish them from each other? A final general point - I'm aware that train numbers do not contain the digits 8 and 9 due to the binary nature of the programme machines. However, quite a lot of lines now use solid state computer technology, and so can presumably cope with 8's and 9's. So why not use them again? Not Binary! The numbering system used for timetables was Octal, when first created on computer the computers used were octal. Train radio communication was also a factor in terms of train numbering. Originally train radio was trialled on the Bakerloo and the Met only so no problem. However, all the lines, apart from the Victoria which had its own unique carrier wave communication system, had to share just three radio channels and despite some clever use of available channels interference between lines could still occur in particular atmospheric conditions, thus it would not have been appropriate to have the same numbering for trains on different lines where mutual radio interference was an issue. Later a fourth channel and subsequently a fifth channel were licensed for train radio use and of course modern Connect tetra radio is a different system entirely. One should also remember that from a control viewpoint there was no such thing as a Circle train which ran as either a District or Met for train radio purposes, similarly Piccs running in and out of Rayners Lane became Mets for train radio purposes in the section between Alperton and Rayners Lane while Mets running to Whitechapel & Barking were Districts between Aldgate and Barking. The numbering of trains is a convenience of flexibility to enable timetabled running of services without necessarily operating particular rolling stock units, otherwise it means little. Positive train identification (PTI) is a term that always made me chuckle because every train has a unique identity but only the fleet management really have a use for that and the original Storno train radio systems could also individually identify which cab was in service via the onboard train radio junction unit which had a unique ID although the facility was only used by radio linemen (when at the control room radio rack) for test purposes. PTI is simply a means of telling the trackside equipment where a timetabled train is but as we know it was not impossible for two trains to be in service with the same running number especially when disruptions of one kind or another forced operating officials to reform trains (renumber trains to regain the service). Of course the service is lost and cannot be replaced but the timetable can in theory be recovered and renumbering allows order to be restored and a chance to route rolling stock to the correct final destinations (the depots) in the hope of minimising disruption to the next days services. |
|
|
|
Post by revupminster on Dec 30, 2013 9:04:54 GMT
The District went something like 1 -23 Upminster -Richmond 30-50 Tower hill- Ealing Broadway 60-69 Wimbledon Edgware Road. Train numbers in the 100's were depot to depot trains ie they only worked the peaks and stabled during the midday. I cannot remember the rest.
|
|
|
|
Post by railtechnician on Dec 30, 2013 16:31:03 GMT
The District went something like 1 -23 Upminster -Richmond 30-50 Tower hill- Ealing Broadway 60-69 Wimbledon Edgware Road. Train numbers in the 100's were depot to depot trains ie they only worked the peaks and stabled during the midday. I cannot remember the rest. Surely you mean 60-67 ! In theory there were/are a maximum of 256 usable service train numbers (000-377 octal, 00000000-11111111 binary) but in fact only 252 were possible (001-374 octal, 00000001-11111100 binary) as programme machines used 8 bit binary coded octal to represent train numbers with 375 used for start of service, 376 used for end of service, 000 and 377 used for engineering test purposes. Octal of course has no 8 because that is represented by 10 and no 9 because that is represented by 11 i.e. 0,1,2,3,4,5,6,7,10,11,12,13,14,15,16,17,20,21,22,23,24,.........................366,367,370,371,372,373,374,375,376,377 |
|
|
|
Post by ruislip on Dec 31, 2013 3:19:23 GMT
In the 70s ISTR Central Line set numbers being under 100.
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Dec 31, 2013 14:22:36 GMT
Any reason the Central line RAT runs under a 4xx number rather than the usual departmental 7xx number?
|
|
|
|
Post by ruislip on Jan 1, 2014 19:03:01 GMT
I have a 1965 Met WTT that featured 1xx set numbers, with 8 and 9 used in the ones position. The uncoupled trains were 4xx. Since the times were not far off from what they used in the early-mid 70s when I lived in Metroland, I wonder what the corresponding 0xx trains were.
|
|
Tom
Administrator
Signalfel?
Posts: 4,196 
|
Post by Tom on Jan 1, 2014 20:04:58 GMT
Wasn't the Victoria line originally numbered in the 3xx series, possibly to avoid conflicting with the Northern City?
|
|
