Riesa-dresden: Tips On Driving Freight Trains Realistically.

Discussion in 'PC Discussion' started by cwf.green, Aug 27, 2021.

  1. cwf.green

    cwf.green Well-Known Member

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    Disclaimer: This thread does not confirm any new features that haven't already been announced for the upcoming DRA DLC. It is speculative and because of that I will try to update it when more information becomes available. The thread is also based on what the freight trains would do IRL, the in-game performance may differ. I have done a lot of research and talked with real world drivers but since I'm not a train driver myself, there may be errors. Feel free to give me criticism and corrections.

    The more realistic the trains become in TSW the more realistic our (as players) techniques and operating procedures have to become to drive the trains in a safe (for the poor AI people) and enjoyable fashion (unless you enjoy game ending SPADs that is ;) ).

    Some of the train parameters that are important to the driver or the dispatching office are train weight, train length, braked weight and the lowest allowed speed of any vehicle in the train. These would determine what the max speed of the train will be, the PZB mode (U,M,O) and the brake setting on each vehicle (G or P).

    To determine the brake settings on each vehicle in the consist, and the braked weight percentage (BrH) I have used the following resource (thanks OpenMinded !):
    [​IMG]
    The brake setting on the locomotive is given by the column "arbeitende Triebfahrzeuge". The next 5 wagons are determined by the middle column ("Wagenzug: Fahrzeug 1-5") and the remaining wagons are determined by the column to the right of the previous ("Wagenzug: Fahrzeug 6-x").

    To determine the PZB mode you simply calculate the BrH as:

    BrH = (Summed Braked weight) / (Train weight),

    with the corresponding reductions found in the sub-columns to the right of the train length columns "-5% etc".

    To determine the trains max allowed speed I used the below resource:
    [​IMG]

    The process goes as follows: find the maximum descending grade of any pre-signal run (track between the main signal and the distant signal) in the lowest diagram "Maßgebendes Gefälle" and then move horizontally to the right to find the BrH of your train (or the highest number below the BrH). Then move vertically up to middle diagram, to the same row of the pre-signal distance of the route. The number you ended on is the Vmax of your train (or the lowest Vmax of any vehicle in the train if that is lower).

    With the method completed we can now calculate the PZB Zugart, Brake setting and Vmax for some typical trains on the route.

    EDIT: I've made a Google spreadsheet with some modifications of the trains with more realistic consists on the route: LINK


    1. Loaded paper train between Riesa Gbf/Röderau and Dresden Hbf (20 x Habbiins + BR185.5):
    Train weight: 1884t. Train length: 496m. BrH: 49. PZB Zugart: U. Vmax: 85 km/h. Brakes: G (all).

    Since this train exceeds 1600t in weight and the couplers are not of UIC-AK type, but the length is below 700m, we need to set all vehicles to G-brake and reduce the braked weight sum by 25%. The Habbiins wagons have a maximum braked weight of 58t, thus the BrH is 49. Since this BrH is below 65 we need to use PZB U. We next find the Vmax in the second table. The maximum descending grade on the "old" line is about 0.6 percent. On the high speed line it is higher, about 1.1 percent but here the pre-signal distance is longer (about 1100-1200m from what I could find) so the 0.6 percent is the critical number. Thus the Vmax is 85 km/h.

    2. Loaded tank train from Riesa Gbf to Weißig Transfer Yard (20 x Zacns + BR185.5):
    Train weight: 1735t. Train length: 322m. BrH: 53. PZB Zugart: U. Vmax: 95 km/h. Brakes: G (all).

    The same logic applies for the brakes, the BrH and the PZB Zugart. The Vmax is higher in part due to the slightly higher BrH and because this part of the route has very light descending grades. Of course, if the train originated at another location the Vmax might have been lower. The train weight is based on an average loaded tank wagon weight for the liquids that are transported to the chemical plant at Wacker Chemie AG (Methanol, Ethanol, Ethyl Chloride, Sulphuric Acid, Potassium Hydroxide etc).

    3. Empty tank train from Weißig Transfer Yard to Riesa Gbf (20 x Zacns + BR185.5):
    Train weight: 536t. Train length: 322m. BrH: 113. PZB Zugart: O. Vmax: 120 km/h. Brakes: P (all).

    This train has such a good BrH that PZB O can be used (based on the BrH at least, please correct me if freight trains are prohibited from using PZB O) and because the train weight is low and the tank wagons can run at 120 km/h while empty this is the Vmax of the train.

    4. Loaded intermodal train between Dresden Hbf and Riesa/Röderau (10 x Sggmrss + BR185.5):
    Train weight: 779t. Train length: 314m. BrH: 100. PZB Zugart: M. Vmax: 115 km/h. Brakes: P (all).

    The Vmax is slightly reduced due to the 0.6 % grades. Train weight is based on previous consists of this type in TSW2.

    5. Empty intermodal train between Dresden Hbf and Riesa/Röderau (10 x Sggmrss + BR185.5):
    Train weight: 379t. Train length: 314m. BrH: 101. PZB Zugart: M. Vmax: 120 km/h. Brakes: P (all).

    The marginally higher BrH bumps the Vmax up to 120 km/h.

    6. Empty auto transport train between Dresden Hbf and Riesa/Röderau (10 x Laaers + BR185.5):
    Train weight: 384t. Train length: 322m. BrH: 101. PZB Zugart: M. Vmax: 120 km/h. Brakes: P (all).

    7. Loaded auto transport train between Dresden Hbf and Riesa/Röderau (10 x Laaers + BR185.5):
    Train weight: 624t. Train length: 322m. BrH: 100. PZB Zugart: M. Vmax: 100 km/h. Brakes: P (all).

    Since the maximum allowed speed for the Laaers wagons while loaded is 100 km/h, this sets the limit to the trains speed.

    Some warnings: if the Vmax and/or advised PZB Zugart is not adhered to (especially for the heavy tank and paper trains) you are likely to SPAD if you encounter a cautionary (Vr0) distant signal. If you run the paper trains at 120 km/h you might get a nasty surprise, at least if you run it in G-brake setting ;)

    To find more guidance on how to select the different brake settings described above, on the locomotive and the freight wagons, go to this message.
     
    Last edited: Sep 23, 2021
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  2. chieflongshin

    chieflongshin Well-Known Member

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    Fair play you going through this. I’ve looked this way too early in the morning and zoned out in the numbers
     
  3. KoeleKoen

    KoeleKoen Well-Known Member

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    A shame dtg simulates none of this, like p or g brakes , even worse if you start a freight service you start with ep/el brakes enabled, which shouldn't even be a thing but for some magical reason actually works (so don't forget to turn them off before departing for a bit more realism)
     
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  4. OpenMinded

    OpenMinded Well-Known Member

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    Nice summary cwf.green !

    Just one comment, as I don’t know if that was clear and it fits to your last sentence: If your train is in G, the PZB mode is automatically “U”, no matter what the BrH. That means with a train in G you will never be faster then 105kmh.
     
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  5. cwf.green

    cwf.green Well-Known Member

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    I have a faint memory of you mentioning this in the previous thread, but thanks for reminding me! :)
    Are there any limitations for freight trains in PZB O if Brh > 111?
     
  6. cwf.green

    cwf.green Well-Known Member

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    I have been told by a driver of the BR186 that the el/pn switch in the cab does not actually control whether the train uses EP-brakes or not but rather it switches between a computer controlled distributor (el) or pneumatically controlled (pn). In (pn)-mode the electronics cannot adjust the brake pipe pressure, for example with the AFB.

    EDIT: Regarding P-/G-brakes, I can neither confirm nor deny whether this will be implemented with DRA.
     
  7. KoeleKoen

    KoeleKoen Well-Known Member

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    Yeah sorry, i meant the switch on the back panel, not the bottom right one, my bad
     
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  8. OpenMinded

    OpenMinded Well-Known Member

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    The only switch you can possibly mean is the nbü switch, which, admittedly is in the wrong position, however, as you are driving a cargo train would not have any influence on what the loco is doing (and I am questioning the principle of nbü in a simulator like TSW, anyway. Would be fun if it could be integrated though).

    I would be more interested if the actual el/ep switch is working in TSW. Has anybody ever tried this? I can’t check myself, currently…
     
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  9. OpenMinded

    OpenMinded Well-Known Member

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    Only Limitation is, of course, the max speed of your slowest waggon, as you have already mentioned above.
     
  10. KoeleKoen

    KoeleKoen Well-Known Member

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    That'd why i call it magic, it does have an influence on freight trains when it shouldn't irl, turning it off changes braking behaviour (at least before the patch, haven't tried since)
     
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  11. cwf.green

    cwf.green Well-Known Member

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    I think that this issue might have been fixed non-visually. The HUD seems to react like it's non EP (accurately) while the visual gauges in the loco act like it's EP (unrealistically). The good thing (at least) is that it only seems to be a cosmetic bug. But maybe it varies between DLC etc.
     
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  12. KoeleKoen

    KoeleKoen Well-Known Member

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    Maybe it got fixed when they added the lzb on the traxx who knows, but having the brakes at least act properly now is a good step
     
  13. OpenMinded

    OpenMinded Well-Known Member

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    Wow, Never realised that switching nbü had any effect at all:o But then, I did not expect it and didn’t look for it.

    But I still don’t understand, what exactly was shown on the HUD differently? If we are talking about el/ep behaviour you should only really notice a difference while using the AFB…
     
  14. davidh0501

    davidh0501 Well-Known Member

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    The trouble is, that as it gets more realistic, so it becomes less of a relaxing game and more of a full time job.
     
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  15. cwf.green

    cwf.green Well-Known Member

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    I'm probably gonna butcher this but from my understanding this is what should happen:

    If the el/pn switch under the desk is in the el position the electronic distributor is used so if you are running with AFB on and move the Vsoll to a speed significantly below your current speed the AFB will apply airbrakes. Also, you might be able to see more precise brake pipe pressures for each step of the train brake (although since the manometer is analog perhaps not).

    If the switch is in pn you only get the pneumatic distributor and AFB will only use E-brake to control the speed.

    If you move the switch at the rear of the cab to EP/NBÜ and the train supports EP-braking (cables connected etc I guess) then train brake applications will propagate at the speed of light and each vehicle will charge the brake pipe from it's own reservoir/line (Haupt-Luft-Leitung/Speiseleitung). Also you have the usual NBÜ Notbremsüberbrückung functionality.

    If the train does not support EP-braking but the switch is in that position I'm not sure what happens, maybe it becomes a normal non-EP braked train or maybe the brakes won't release?

    If the switch is in the 0 position then I think you simply get a non-EP braked train.

    In TSW2 I'm not sure what happens if the el/pn switch is in either position (i.e. whether it is at all functional) but I do know that if you use a BR185.5 train without NBÜ/ep function and rear-cab switch is in that position the analog manometer gauge for the brake pressure will act as if the train is actually EP-braked (quick BP charging etc), however the actual brake pipe pressure (shown by the HUD gauge) still works like a non-EP train.

    Like I said, I'm almost surely butchering a lot so feel free to correct my errors.
     
    Last edited: Aug 28, 2021
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  16. solicitr

    solicitr Well-Known Member

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    AFAIK, TSW does not model R, P and G brake modes. But I don't know which mode the simugraph modeling is perma-locked to. TSW certainly does not model coupler behavior.
     
  17. OpenMinded

    OpenMinded Well-Known Member

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    Alright, got you. And you explained the EP brake quite well. Especially liked the „lightspeed“ bit:cool:

    But the nbü button does nothing else but influencing nbü behaviour. It will have no effect on a cargo train, hence why I was so interested in what actually changes if you turn this switch on in TSW.

    the el/ep is clear and it should have an effect in TSW, even I must admit, I have never checked this myself.
     
  18. breblimator

    breblimator Well-Known Member

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    Hope you are the person Matt mentioned as complicit in all these BRD brake improvements :) I can't wait to test it \o/ BR o7
     
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  19. OpenMinded

    OpenMinded Well-Known Member

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    :cool:Same here, love it…
     
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  20. Lamplight

    Lamplight Well-Known Member

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    As usual, fantastic work cwf.green. I look forward to using your guide with the newly modelled brake settings for BRD :)
     
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  21. KoeleKoen

    KoeleKoen Well-Known Member

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    Can't wait to test it out cwf.green Just a shame there's so little freight services on dresden to play with these..
     
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  22. FD1003

    FD1003 Well-Known Member

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    Apologies if I missed something, but I need some help to calculate the BrH.

    First, the braked mass is shown here on the locomotive (for each kind of brake selected):
    16306650380355785999653090239762.jpg
    This is on the BR155.

    However I can't find this information on the freight wagons, I don't believe it's printed on their side is it? Not being able to do research in German, I did the next best thing, which is to do it in Italian, and our documentation says the braked mass should be indicated on the plate where the P/G switch is mounted. But I can't see it (not even IRL).
    Screenshot_20210903-131254_Drive.jpg
    SOURCE

    This document goes on listing all the braking values for all Italian rolling stock (locomotives and multiple units and some pax coaches), but sadly not for freight wagons.

    EDIT: I found those numbers on another thread of yours: which indicates the BrH (not the max braked weight)
    Habiins 344: 100/64
    Falns 183: 116/65
    Shimmns-u 708: 129/66 (wheel flats? lol)
    Shimmns-ttu 722: 114/57
    Roos-t: 111/64
    Laaers 560: 100/100
    Sggmrss: 100/100

    Any idea whether this numbers are accurate for the BRD loads?

    Also for BrH shouldn't you multiply by 100 after dividing the total braked mass and the train mass?

    EDIT 2: So far I managed to find the braked weight on the Laaers, the Habbiins and the Sggmrss that have automatic load braking (the braked mass = total wagon mass (empty+payload) up to the max value). Which is in-line with your BrH values (because the empty wagon has the same mass and braked mass - so a BrH of 100%)
    Screenshot_20210903-184752_Drive.jpg
    Also described here in English
    Still no idea about the other wagons where I can't find that diagram or any other diagram described in the source material above.
     
    Last edited: Sep 3, 2021
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  23. OpenMinded

    OpenMinded Well-Known Member

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    Yes, irl you will always find the brake weights written in one way or another on the side of the waggon. I think you have already identified all formats above. If you need more infos I will try to explain a bit more on certain topics.

    Also, BrH can be above 100. On last nights stream you could see the brake weights of the Sggmrss, which was 108t max (36t+72t). So the lowest brake weight is 36t, but if I am not mistaken an empty Sggmrss weighs less then that (could be wrong with this particular waggon, though).
    C3979296-BBA7-4836-9F0D-88BA792AAA35.png
     
    Last edited: Sep 4, 2021
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  24. FD1003

    FD1003 Well-Known Member

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    Thank you very much for the information. I understood that the BrH can be above 100 only if the wagon is not equipped with automatic load braking, which is described in the (italian) document I cited above as: "The braked mass is equal to the total mass (payload + empty wagon) up to the max value indicated on the side of the wagon." And is in-line with cwf.green's value of BrH=100% when empty.

    In-game the only wagons which I found have this kind of brake are the ones mentioned above (from which you sent your screenshot).
    20210903_184006.png

    I still don't know where to find this information on the other wagons, I checked every one of them (apart from the Falns) and I can't see the braked mass anywhere. I've also been looking at other numbers and things on the side of the wagon without any luck. I'll try harder tomorrow.

    Sorry for the awkward english TBH I am struggling to write things that make sense especially when I don't know how to properly translate some terms...
     
    Last edited: Sep 4, 2021
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  25. OpenMinded

    OpenMinded Well-Known Member

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    No worries, your English sounds perfectly understandable! TBH, I never checked in game for braked weight on the Waggons. I’ll only have the possibility to do this on Monday. If they are not modelled, I’ll try to find the real world values, which would ideally be identical;)
     
  26. tbaac

    tbaac Active Member

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    Thanks for this thread, really interesting. Are P and G abbreviations for something? It can be fun to know these things. Thanks :)
     
  27. FD1003

    FD1003 Well-Known Member

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    Gûterzug e Personenzug - Goods (Freight) and Passenger I believe
     
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  28. tbaac

    tbaac Active Member

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    Thanks for that. It helps me picture it in my head if I know roughly what it means :)
     
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  29. cwf.green

    cwf.green Well-Known Member

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    Here are all the braked weight values (empty brake weight/change-over weight/loaded brake weight):
    Falns 183: (28t / 48t / 58t)
    Shimmns-u 708: (29t / 48t / 59t)
    Shimmns-ttu 722: (27t / 48t / 51t)
    Roos-t 645: (28t / 48t / 54t)
    Zacns: (26t / 48t / 58t)

    The following wagons have automatic load sensing so the brake force is continuously (or sometimes discretely) increased up to a maximum weight (BrH = 100 for all weights up to that max weight).

    Habbiins 344: (up to 58t)
    Laaers 560: (up to 56t)
    Sggmrss (up to 108t)
     
    Last edited: Sep 5, 2021
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  30. cwf.green

    cwf.green Well-Known Member

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    Interestingly, the G- and P-brake settings are both most commonly used for freight trains nowadays and passenger trains instead use a third setting R-brake (Rapid) or some combination with added brake technologies like R+Wb ( + eddy current brake) or R+Mg ( + magnetic track brake).

    The function of R-brake historically was to increase the brake cylinder pressure above a certain speed to counteract the steep fading of the friction in the cast iron block brakes at high speeds. The R-brake setting is not young, I read about plans to implement it as early as 1930s. Not sure when it was actually invented though. On modern disc braked trains the R-brake setting will often keep the higher brake cylinder pressure constant at all speeds (or on some locomotives like the BR101 it actually *decreases* the brake cylinder pressure at high speeds).
     
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  31. FD1003

    FD1003 Well-Known Member

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    Thank you very much! Would I be too annoying if I asked you where you got those from? Are those printed in the TSW wagons or did you use other resources? If I am too annoying I'm sorry

    That's very interesting, I believe the R brakes use electrical signals, while both G and P use the traditional air system right?
     
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  32. cwf.green

    cwf.green Well-Known Member

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    No problem! Most of the values I already had in a document with data I got from drivers over the years. I also doublechecked it against the values on the zusiwiki, not all of the values are on that page though.

    The brake settings (GPR) only affect how fast the brake cylinder vents and charges and the brake cylinder pressure, it is independent of how the brake signal is transmitted.

    You're thinking of EP-brakes where the brake signal is electric rather than pneumatic (but the brake cylinders still fill up with air when braking). There might be rules that require the brakes to be switched to R (or R+Mg) brakes when EP-brakes are in use that I'm unaware of but IRL you'll never see EP-brakes used on freight trains in Europe (outside of a few tests that have been performed over the years or perhaps some special unit train).
     
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  33. cwf.green

    cwf.green Well-Known Member

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    OpenMinded I have a question for you :)
    If the freight train runs in G/P or LL (i.e. either only the loco in G-brake or loco + 5 first wagons), would PZB U be enforced?

    The reason I ask is because I've seen several intermodal trains weighing about 1300-1400t (i.e. LL) but that use exclusively wagons that can run at 120 km/h when loaded (up to a level) so if these trains were limited to PZB U they wouldn't be able to reach their max speeds.
     
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  34. cwf.green

    cwf.green Well-Known Member

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    You are correct that sometimes the BrH will be above 100, even for freight wagons. One example is the Zacns that has BrH = (26 / 22.6 ) * 100 = 115 when the wagon is empty.

    However, this would not occur on wagons such as the Sggrmss with continuous and automatic load sensing. The 36t + 72t number you saw were the *max* brake weight per "wagon" (one part has 2 bogies and 4 axles, the other has only 1 bogie and 2 axles). For all gross weights up to 36t and 72t respectively, on each half, the brake force is proportionally matched (by either changing the ratio for the brake cylinder pressure or moment arms/rigging ratios) so that it corresponds to a BrH of 100. When the Sggmrss is empty the weight is 29.5t so the brake weight would only be 29.5t in this situation.
     
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  35. FD1003

    FD1003 Well-Known Member

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    Right, makes sense thanks again :)

    Oops, yep I got mixed up with the EP system, I kind of know the basics of how it works but I am still not very familiar with It. Thanks again
     
    Last edited: Sep 5, 2021
  36. OpenMinded

    OpenMinded Well-Known Member

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    Ups, you are correct. Didn’t realise that it was actually a permanently coupled formation, as I didn’t pay attention to the Sggrmss :o And of course, you can actually also see them with more weights in between.

    But, are you sure you will never see BrH above 100 for auto load sensing? As far as I know there are Waggons out there where it will not always go down to lowest weight. I’ll try to find the example I have in mind and post it here.
     
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  37. OpenMinded

    OpenMinded Well-Known Member

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    No, in this case your train BRA is to be set to P. Only if the whole train is in G (usually 1600t+) you are forced to mode U.

    The whole „front of train in G“ thing is basically only a compromise for wear and tear of the brakes in the whole train. They are otherwise constantly pulled and bumped. Also, it achieves a more homogeneous and more efficient way to brake the train. Hence the train is still considered to be in P.
     
    Last edited: Sep 5, 2021
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  38. cwf.green

    cwf.green Well-Known Member

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    Ah, that's nice to hear. That would mean that most intermodal trains that run on DRA (usually around 25 twins of Sggmrss/Sggns or single Sgnss 80 total train length around 650-670m) can be run at maybe 110-120 km/h since their train weights would be below 1600t. Thanks for the info :)

    EDIT: Regarding your previous question if you can't see BrH more than 100 for auto load sensing. As far as I understand it, on paper you would not see a higher BrH (per wagon) than 100 when the brake weight is continuous (perhaps there are some rare situations like you pointed at where the minimum brake weight is above the empty weight) but in practice it can be higher than 100 because the function (brake force) = stopping distance is not linear.

    It's hard to explain but BrH is just a function of stopping distance, if the same wagon is changed so that it has more drag the BrH will increase even though the brake force was the same! This is because when assessing the Brake weight of the wagons it is done via stopping distance either as 500m trains or in slip-tests (single wagon).

    When wagons with automatic load sensing are assessed to get the brake weight to print on the wagons they have to be tested at 3 weights: empty weight, weight at which brake force is maximized and max gross weight. The "58t max" or whatever brake weight is then calculated from the *minimum* of the two last tests. At least this is my understanding from reading UIC leaflet 544-1. So you can have weights where the practical BrH is slightly lower or slightly higher etc.

    However, some older "automatic load sensing" systems actually only have two settings but the wagon automatically changes between "empty" and "load" without needing manual input. For these the practical BrH will change all over the place. I'm not aware of how drivers/dispatch office people determine the BrH of the whole train with this type of equipment. Perhaps the worst case?
     
    Last edited: Sep 5, 2021
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  39. cwf.green

    cwf.green Well-Known Member

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    Here is the assessment instructions I referred to above
    EN16834_load.png

    Maybe I can explain (at least my interpretation) of why several tests need to be performed even though naively one might think you only need to perform two tests (one for empty and one for max gross weight or the weight at which the max brake weight is attained).

    Since the brake weight is determined from the (BrH x wagon weight / 100) and the BrH is in turn a function of the stopping distance at different speeds, if two weights have the same brake force (for example the empty weight and the weight right below the change-over weight for a manual "empty"/"load" system, would there be a difference in stopping distance and thus in BrH between the two wagons?

    The answer is yes. Even though they both have the same brakeforce, the empty wagon has a higher deceleration due to drag (since drag does not depend on weight) and thus the calculated BrH will be higher than for the heavier wagon. You want your Brake weight to be such that the wagon should achieve it at all weights and hence you need to use the worst case (lowest BrH). Hope that makes more sense.
     
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  40. FD1003

    FD1003 Well-Known Member

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    I know I don't have much of a place in this whole discussion but this is how I understood it as well and how it's described on the document I quoted above. Although I can see that it could be the case for a wagon to have a "minimum" braked mass as well, but it would be a first for me.
     
  41. cwf.green

    cwf.green Well-Known Member

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    I like your opinion (because it agrees with mine) :D
     
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  42. OpenMinded

    OpenMinded Well-Known Member

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    This is interesting stuff (not many will think so, I guess:cool:).

    In case of the Waggons with empty/load devices, this has not always been like described in the en 16834. In fact, I know that only about 10 years ago (I have a reference from 2010), there was no test with empty weight necessary. Only the worst case in terms of stopping distances were tested, meaning that only a weight just below the change over load and the max weight were used to define brake weight.

    TBH, I have absolutely no idea why testing the empty waggon would have any influence on the BrH calculation, as only the worst case will define the published value on the waggon, as you say as well.

    hence, I agree with you as well, but have no idea why it is done the way it is…

    and just for the fun of it, here the reference from about 10 years ago (sorry, German again…):

    45F9C19F-2366-41F2-AA8B-B5C125B5BD2E.jpeg
     
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  43. cwf.green

    cwf.green Well-Known Member

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    I do! ;)

    I agree with you that it is quite useless to test the empty weight + empty brake configuration since, as you say, this would be a "best case" rather than the worst case. I guess when it comes to automatic load sensing systems you need to define some minimum brake force and then it becomes more reasonable to test it because perhaps the minimum brake force was too low (for some reason). I'm just guessing here though.

    I think that in TSW the automatic load sensing systems are implemented with a linear interpolation.
    There is a minimum brake force and a maximum brake force and a line is drawn between those two values. If you only make sure that the upper end of the line gives the wagon a BrH = 100 then maybe the lower end is too low so that the BrH there is something like 80. This may be the reason why they test both conditions.

    Again, I'm skeptical whether this is necessary since even if you scale the empty weight brake force as just

    BF_empty = BF_max * empty_weight / max_weight

    you should get a practical BrH at the empty condition that is slightly higher than 100 because of drag.

    I made a numerical script that would calculate the stopping distance of different consists in TSW based on drag, rolling resistance, brake force, mass and speed so that I could provide DTG with just the brake force values rather than require them to perform "slip-tests" etc (as a sort of improvement of my previous threads where I just gave the stopping distances).
    What I found was that the relationship between wagon brake force and BrH is non-linear. I.e. if you double the (brake force / mass) the BrH will not double etc. This probably doesn't come as a surprise but it more non-linear than I expected, especially at very low weights or very high weights.

    Btw, my copy of the UIC 544-1 leaflet (basically the same as EN 16834) is both quite old an in German so since my German is very poor I was happy to get a copy of the EN 16834 :D
     
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  44. cwf.green

    cwf.green Well-Known Member

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    One thing I forgot to ask: When the train is made up of twin units like the Sggmrss or Laaers, would the "5 first wagons" in LL count as the 5 first twins (i.e. 2x5) or the five first halves (i.e. 2.5 twins)? Iirc the Sggmrss has two distributors so you can run one half at G-brake and the other at P-brake (not saying this is advisable).
     
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  45. OpenMinded

    OpenMinded Well-Known Member

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    That’s a good point. The word „Fahrzeug“ in my table means „vehicle“. A waggon can be made up of several vehicles. Hence, you are right with your assumption, you count each individual vehicle. I believe that you don’t mix a Setting within a Waggon. If you have a whole set of Sggmrss you would actually set 6vehicles to G. Hope that makes sense?
     
    Last edited: Sep 6, 2021
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  46. cwf.green

    cwf.green Well-Known Member

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    That makes sense! Thanks.
     
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  47. Oldcustard

    Oldcustard Member

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    This is great info, thank you so much! Is there a resource for the maximum pre-signal grade and braking distance? Not just for Riesa-Dresden, but also for other routes in TSW2?
     
  48. delucadomenico2009

    delucadomenico2009 Active Member

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    The weagons is considerated the couple or the wagon set. For exemple some U-type "wagons" are composed with 6 or 7 cars too. Theese ones are particular likes the intermodal ones. There are a lot of variant of them and all of them are different from the position of the container to le lenght of the car or if there is axle in the middle or a carrel. Anyway, itermodals always run at SS speed indipendet from the brh and pzb is always set in M position. If the trains is too long or weight, easly will be add another loco and usually on the rear to do a sandwich formation. (Yes there is a difference if you do a couple in front or a sandwich). Also i have red all the topic, and everyone is missing the electric brake of the locomotive. This one as a paradox are more stronger on fright train than a passenger one. Everything is correct yes, but all theese calculation are done during the train formation from the dispatcher. Also in real life is used to add a 15% of tollerance to this number. An easy exemple can be shutting and light freight services. Everytime you separete or adding 1 o X cars the brh of the whole train will change, and if you are on the limit of your brh a new or more cars will increase it and this means that you need to reset the train again. This procedure normaly takes 5 minutes if you are fast. So to make the things more easy is used to see just the brh of the train, than set the pzb in just U or M and as a conseguence you will get you max operating speed that must follow the restriction of the Pzb and of the slower cars of your formation. The brakes are always set on G mode. Also there is a trick to overide the rule of the first 5 cars in P mode. Just make the first 5 cars the heavyer and so you can directly set all cars in G. As a driver i just need to know my Vmax and the brh. The second one just inform me of "how i need to be aggressive" with the brakes. Than experiance wil do everything, from route knowledge to loco knowledge. Than there are a lot of external thing than can change the rules but this one usually be showed on your timetable or the signaller tells you them during the run. Just for exemple in italy after the Viareggio Disaster in 2009, all loaded tank wagons with Dangerous liquid just like Gas, oil, petrol ecc ecc Are capped at 80kmh and 30kmh throught greater stations, instead the train can normally runs at 100 or 120. The same rule works with tank-containers on intermodal if the take a Dangerous fluid.
     
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  49. cwf.green

    cwf.green Well-Known Member

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    Interesting stuff! You will note that I already mentioned that IRL the driver does not have to do these calculations, but since we don't have any dispatch office in TSW and (currently) I only have access to the MBrH/Vmax for passenger trains on the route I have to use some more primitive methods ;)
     
  50. cwf.green

    cwf.green Well-Known Member

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    I made a Google spreadsheet of some freight consists that are not currently in the route but I hope might be released some time in the future *if* there is a change in the timetable. Note that these consists do not currently feature on the route so it is more for curiosity at this point (and perhaps always will be). Here is the link
     
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