Started by Vladki, April 08, 2015, 08:16:52 PM
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Quote from: jamespetts on October 26, 2015, 11:50:24 PMOn the subject of T-signals, I have found an interesting reference in "The London Tilbury & Southend Railway; a history of the company and the line" (volume 2) at p. 139 suggesting that these might have been used in the U. K. at some point. The text is as follows,"Double line sections, which always formed the majority of the LT&S system, were originally worked on time-interval. No use was made for signalling purposes of the Electric Telegraph which had been installed throughout. Each station had the usual double-armed 'Station Semaphore' with one arm for each direction, showing horizontal (red light) for stop, 45 degrees (green light) for caution, and vertical (hidden inside the slotted post) (white light) for clear."
QuoteWhat is not clear is whether those were signals for trains entering the station or for leaving it, and, if for entering it, where the trains would be held if not at the signal.Can anyone tell me a little more about how the operation of these Swedish signals worked, and in particular where trains would stop outside the station, and how trains were signalled to leave the station?
Quote from: jamespetts on November 04, 2015, 07:13:33 PMMay I ask whether this is describing the absolute block or time interval method of signalling, or whether this is not clear from the text?
QuoteWhen you refer to working "without any physical objects", are you referring to something similar to "tokenless block"; were the signals interlocked with the telegraph to prevent more than one train entering the single line section in opposite directions?
QuoteI am looking into "station signals" as part of time interval signalling (which is why I asked about that); I am waiting to hear back from somebody at the Signal Record Society who has told me that he will provide me with some more information as to the working of time interval signals at junctions and stations presently (the current implementation in the code I do not think deals with stations and junctions correctly).
Quote from: Ves on November 04, 2015, 10:31:52 PMAs far as I have understood it, the interlocking was a human with the key to the signals. In theory, a station chief could wrongly send a train (and set points and signals to be clear) in the head direction of an approaching train. The "interlocking" is the telegram he got from the machine.
QuoteInterresting with station signals! Are they supposed to be placed like the T-semaphore or what kind of logic will they have?
QuoteAlso, sending multiple trains in the same direction: were there signals along the track, or was this in effect permissive or even time interval working in this respect? How early were these signals, with the block telegraph instruments, in use?
QuoteAlso, do you know whether these signals were normal clear or normal danger?
Quote from: Ves on November 06, 2015, 03:46:08 PMI gues you are right that it more or less is identical to token block signaling between stations.Reason a train could be sent down a line before the former train had arrived to the next station is, if either the former train was behind the schedule, or this train is an "extra train" (meaning its not figuring on the time schedule).I do think that they planned their time schedules so no train had to be sent before the former had arrived to the next station. However, when delays occured or there where this "extra train", this could be done in order to prevent further delayment of the schedule.
QuoteAs with early British signals, any driver approaching such a signal showing danger would be expected to bring his train to a stand before any points, rather than stop at the signal itself.
QuoteCould you find more about the signal on the left picture here: http://www.ekeving.se/si/mek/index.html?
QuoteDo you have any idea what sign could be used for early drive-by-sight signal?
QuoteWhat sign is usual on gates over railway (gates of depot and such) ?
Quote from: Ves on November 18, 2015, 10:38:52 PM...Questions:As to the five aspect choose signal I have a question: will the "Clear-main" be showed also when the train is stopping at the station, or is there a way to make this state only show when when the train drive through the station (using the main route)?
QuoteRegarding the 3 light choose signal, is that needed along with the 5 light choose signal?
QuoteWill there be implemented a signaltype that works as a T-signal?
QuoteIn the current implementation, clear-main is shown when a train is stopping at its designated platform, or passing through on its designated route. I am considering changing this as requested in another thread to show only in the latter case, and to show caution-main in the former case.
QuoteIs this a question to me about the code, or to another Pak128.Sweden contributor about what signals that you need to make? If the former, I am afraid that I do not understand. If the latter, my apologies for possibly confusing it with the former.
QuoteI have been giving this some careful consideration and am still not decided. This would be quite tricky to implement: it would require a signal being assigned to a station, and then facing in one direction but nonetheless controlling the movement of trains in both directions (or in theory all four directions if a station was a + shape, which is possible in principle), add code for that single signal to govern all departures from a station independently in each direction (for time interval, which is the method in which that signal was used in the UK, storing independently for each of the possible four directions the time at which the train left), and cause the trains to stop at the right point outside the station rather than, as at present, immediately beside the signal, on the same tile as it. Further, logic would have to allow it to control both entry to and exit from the station and to know in each case which it is doing. This is all made much more difficult by the way in which signalling is implemented, in which trains try to reserve tiles ahead on their route one by one, and, when they reach a signal, engage complex logic as to both whether and to where the train may then proceed from where it is now, and what the state of that signal should be. As may be appreciated, this system is particularly difficult to implement with signals controlling multiple tracks at the same time. I have still not worked out a clear idea of how this all could be implemented in the code, nor do I even understand how the real signals worked to a full level of detail.
Quote from: Ves on November 19, 2015, 12:33:17 AMI would very much support that change! Maybe make it optional?
Quotehaha, I think that was a general question to wether it really would be necesary for a pakset to have two choose signals. "Why would one place the one over the other" would be my question, and Im kind of struggling to find an answer to that :-)
QuoteGreat, Im really looking forward to see the results (if it comes that far!) of this :-)If I may throw in a proposal:In reallity, all the points at that time where not necesarily securily locked. If you add a BIG speed penalty for "ungarded" points (simulating that the train driver would have to stop the train, run forward and check wether the point is set and the track is clear, then run back again), then a T-signal could "guard" all points in a specified radius? Normal signals (in pre track circuit blocks) would also guard signals behind the signal in a certain distance, and when track circuit blocks become available, all points behind the signal up to next signal (unlimited distance) are considered guarded.
QuoteIf the line is branching between two stations, a signalbox and a T-signal could be placed and that junction is considered guarded in all directions. Routes would always be booked THROUGH the T-signal, never up and until the T-signal.
QuoteRegarding multifacing T-signals: Scroll down on this page: http://www.ekeving.se/si/mek/T-sem/T-sem.html it shows for 4 directions!
Quote from: Ves on November 18, 2015, 10:38:52 PMMaybe fig. 17 (Grön bansignaltavla och dess placering) on this link: http://www.ekeving.se/t/sao41/sif.html?The "one way sign" could be fig. 10 (Spårspärrskärm) on that link?"End of choose" could be fig. fig.9 b2.
QuoteFirstly some comments:Combined signal was to my knowledge never used with semaphores. First with track circuit blocks, a signal could show the state of the next signal.
QuoteThe maxspeed should be quite higher than 80kmh for the pre ATC signals, like 160kmh as its in pakbritain.
QuoteI have some corrections which I will try to explain via the underneath timeline:
Quote from: Vladki on November 20, 2015, 12:43:38 AMI have already used these:- one way sign - red sign (fig 14/15) or dwarf signal at 11a- end of choose - green sign (fig 17/18) or dwarf signal at 11b- end of signalling - dwarf signal at 11c - no sign yet. if I understand correctly, 9b is just 9a turned by 90°. I would prefer something more like a sign.
QuoteBy railway gate I mean a gate that is used e.g. when track enters factory grounds surrounded by wall or fence. I have made such a gate for pak128.CS here: http://forum.simutrans.com/index.php?topic=9551.msg102556#msg102556Real life version: http://www.vlakregion.cz/trate/041/vlecky/sadova/sadova_vlecky_13.jpg
QuoteThe blue diamond on those pictures is a Czechoslovak railway sign meaning "shunting forbidden" and is placed where movements are physically impossible - fixed version on dead end or closed gate, changeable version on derailers, turntables. Old mechanic shunting semaphore was also a blue diamond (otherwise similar to mechanical presignal - it turned upwards when cleared).So, which sign is the swedish equivalent for this blue diamond? I guess fig 9a, 10 or 12.
Quotein that case I would just make the choose signal with two arms, and the 3-armed semaphore will not be used at all
QuoteHere https://en.wikipedia.org/wiki/Swedish_railway_signalling they write, that the max is 80 km/h without ATC.Here https://en.wikipedia.org/wiki/High-speed_rail_in_Sweden they write, that current max with ATC is 200 km/h
QuoteSome of the dates are in contradiction with your earlier post- presignals- two/three arm semaphoresDo you have some reference, which is correct?
Quote from: Vladki on November 30, 2015, 08:26:20 PMRailway Gate added to SVN
QuoteWhat about using signal 5.4 for end of choose, and "Grön bansignaltavla" for end of signalling
Quote from: Ves on December 01, 2015, 12:26:13 AMsignal 5.4 (page 39) would be excelent for end of choose.
QuoteAs far as I know, there are no ways to differ an "ATC-"signal from a normal signal, other than the ballisers. I know there are signs for when the train enters and exits an ATC-line, and those signs along with other "ATC-signs" are at page 96 ("ATC börjar" and "ATC slutar"). However, I think it would be fine to use the triangle or the diamond you suggested. This makes me remembering that normally on an "infartssignal" (=choose signal), there is a little yellow square sign telling wich station is ahead (page 17, sign with "HOA A1/2"). Would this be suitable to distinguish that this is a choose signal?