PZB Zwangsbremsung at Lf7?

    I'm sure whether to post this in the support section or here because I don't think it is a bug but rather a correctly modelled function in TS addons with PZB.


    Sometimes when the speed drops significantly (>= 40km/h) but there is only a Lf6 sign and no PZB 1000hz magnet, there will still be an emergency brake application if the trains speed has not dropped sufficiently when close to the Lf7 sign.


    Some examples of this are the 150-110km/h speed change north of Osnabrück and the 160-120km/h speed change just outside Weissenthurm when traveling from Koblenz to Köln (update 1.22 beta). I have had this happen in the vR BR101, the 3DZUG ICE1 and I think the RWA Railjet 1116.


    I checked out the section where this happens on the Köln-Koblenz and there are 2 or 3 magnets (couldn't see what type) a few hundred meters (maybe 400) before the Lf7 sign.


    I have never heard that this was a function of PZB90, does anyone have more information about this function/behavior?


    Feel free to respond in German if you don't speak English, I feel that Google translate actually works quite well, and in the worst case I have Germans friends on Steam that can translate ^^

    Indeed 2 drive through in direction Boppard and Bingen have the suddenly tempo drop from 130km/h to 40km/h without a Traffic sign Order before, and there is no Plattform change, on the Frankfurt-Koblenz track. I think as player, you cannot fix that little problem.:( I found no tutorial to this. Useful tutorials for TS are rar.

    Thanks for the information. I checked inside the editor and noticed one of the magnets were called GPA-something so it makes sense that they correspond to Geschwindigkeitsprüfabschnitt.


    Man, it's not always so easy to avoid the emergency brakes hehe. When driving at 160 km/h and passing a Zs3v distant display it can be quite tricky to throttle down and brake sufficiently in time, I feel. Maybe because the LOD-visibility of the signals are not that great (DTG signals are terrible for this since they don't seem to even have LOD) so you only see what speed is announced maybe 100m before the signal and end up having to brake harshly (step 5 or 6 on the BR401). I guess route knowledge comes into play here.

    Correct, speed reductions signaled with Lf 1 and Lf 2 or Lf 6 and Lf 7 are known from route knowledge or can also be looked up in the book timetable / EBuLa or the La. The same applies to speeds signaled on the distant signal if they are standard. If a surprisingly and unexpectedly lower speed is signaled to you, depending on the type of train, it may become sporty, especially since in the H / V system speed reductions of up to 70 km / h are announced with Vr 1 and Zs 3v. If the Zs3v signal is rather poorly visible, it is really only seen very late

    Yeah, I did some calculations/testing from the GPA tables.

    In the worst case where you apply brakes just at the Lf6/Zs3v from 160km/h for a 100km/h speed restriction the deceleration needed is (Vmax = 120km/h) calculated as:


    Braking distance: S = v_1T/2 + (v_1^2 - v_2^2)/2a, T ~ 4s (4 seconds for the electric brakes to build up and the brake cylinders to reach demanded pressure)


    S = 1000m - 485m (2000hz magnet location from distant sign/signal) = 515m


    a = (v1^2 - v2^2)/2(S - vT/2) = (160^2 - 120^2)/((2*(3.6^2)*(515m - 2*160/3.6))) ~ 1m/s^2 !


    That's almost fullbrake (VB) territory, probably not the most comfortable for the passengers. xD


    More realistically you might have time to apply the brakes so that they have achieved full retardation before passing the sign/signal, if so step 5 or 6 to be safe should be enough. But as FraPre said, it might cause some "white knuckles"/sweating, so it is best to know of the restriction from route knowledge/"buchfahrplan"/ebula as mentioned ;).

    So if one assumes an initial speed of 160 km / h, it is a matter of trains that have the appropriate braking equipment and appropriate braking percentages. A reduction from 160 Km/h to 100 Km/h, even if only noticed at the last moment, certainly no longer causes a sweat, a Vr 0 more likely. Especially with Vr 0 there is no longer any hesitation, but usually started to brake by means of rapid braking, also to activate the magnetic rail brake. In order to decelerate from 160 km / h to 100 km / h, a corresponding service brake position is certainly sufficient to keep the GPA below 115 km / h (safety reserve).

    Zitat von FraPre

    So if one assumes an initial speed of 160 km / h, it is a matter of trains that have the appropriate braking equipment and appropriate braking percentages. A reduction from 160 Km/h to 100 Km/h, even if only noticed at the last moment, certainly no longer causes a sweat, a Vr 0 more likely. Especially with Vr 0 there is no longer any hesitation, but usually started to brake by means of rapid braking, also to activate the magnetic rail brake. In order to decelerate from 160 km / h to 100 km / h, a corresponding service brake position is certainly sufficient to keep the GPA below 115 km / h (safety reserve).

    I should've clarified that I was referring to the 3DZUG BR401 (with my updated brakes to achieve stopping distance of 900-950m in VB, *not* with Mg-bremse according to information I got from drivers at drehscheibe-foren). To brake from 160-100 km/h in 1000m is quite comfortable as you say, but the addition of the GPA "check" requires some harder braking because you need to shed 72% of the kinetic energy change in half the distance (2000hz magnet trips above 120km/h in 515m). (160^2 - 120^2)/(160^2 - 100^2) ~ 0.72.


    But of course it is perfectly doable as drivers have to do it every day.

    It was just surprising/difficult for me because I wasn't used to it.


    "a corresponding service brake position is certainly sufficient". What is this "service brake position"? 1 bar or VB (1.5 bar)?

    You really have to see that, but yes if necessary up to the full brake position (3.5 - 3.2 bar HLL)

    Is it worth making such complex calculations for a simulated vehicle?

    In the event that I have to slow down really quickly, I would always try to control the magnetic rail brake, and of course reduce the braking force again as soon as I am in the safe area. With an emergency stop until the end, I'll vml. also come to a stop in front of the signal, because the braking hundredths have to do that, but you are moving on pretty borderline braking lines. That would be more of a stress for me, but maybe just a matter of getting used to.