Zs1 - Befehl 40 operation

[MrG]

Getting the hang of things now. Silly question perhaps, but for how long should one run at vmax 40 km/h after operating the command switch when passing a lit Zs1?

[Frank Wenzel]

This depends on the signal at which you get the Zs1.

In simple terms: If it is a block signal on a free line between two stations, then only until the end of the train has passed the signal. For signals in the station you have to distinguish again: At the entry signal and intermediate signal, it is valid until the next signal (again train end) or the usual stop. At the exit signal it is valid until the end of the following turnout area (again train end).

Sure, someone else can describe this in more detail, but for home use it's enough for me an Zusi usually doesn't grumble.

Happy driving

[Zimmer]

Hi MrG,

it's not a silly question at all – in fact it's one of the crucial questions every train driver is asked sooner or later in his exams.

The answer is rather simple – the restriction in speed is valid until your entire train has left the "following point area" (=anschließender Weichenbereich). But the key question is: where is that? It's a bit complicated though, because it depends on the type of signal the Zs 1 has been shown at.

(A) It's been shown at a Home Signal of a Station (Einfahr- oder Zwischensignal): The following main signal (Zwischen- oder Ausfahrsignal) is the end. Have the entire train pass that, and you may proceed as indicated by that very signal and your timetable.

(B) It's been shown at an Exit Signal of a Station (Ausfahrsignal): The last point in your path is the end. Always remember "last axle, last point" and you're quite good on that.

(C) It's been shown at a Block Signal (outside any station limits): Have the entire train pass the signal and add 400 metres.

If you're unsure, you can always look it up later in the report you get after finishing the journey – the restriction is indicated in the graph.

Now Frank was a bit faster - but the restrictions of a Zs 1 do not end at your usual halting spot, they always are valid until you've passed the following signal (Case A).

Hope I could help you,


Johannes

[F. Schn.]

If it is a block signal on a free line between two stations, then only until the end of the train has passed the signal.

Only for old Western Germay timetables before about the 1990s. For Eastern Germany and new timetables in this special case the start of the train is enaugh.
For the rest of the statements end of the train is correct.

or the usual stop

This exception has been removed for Zs1 at ... er... I guess about ~2015? For regular signalling it remains active.

Case C of Zimmer does not sound correct to me.

[Frank Wenzel]

...

or the usual stop

This exception has been removed for Zs1 at ... er... I guess about ~2015? For regular signalling it remains active...

This ist what happens when reading older web sources

[halfur]

The main question seems to have been answered by now, but I'd like to add a small sidenote to aid understanding the reasoning behind this. For the dispatcher to signal Zs1 they have to have checked all regular preconditions for allowing a train run. So there's basically no reason for the speed restriction apart from the points on the path. Those might have speed restrictions, and since these can't be signalled by a Zs1 one has to fall back to the slowest speed that might be necessary, thus 40km/h.

Once you've passed all points on the path there is no reason for a speed restriction anymore, as previously mentioned the dispatcher has to have made sure there are no obstructions on the path.

[Zimmer]

That's a quite accurate summary and in fact the more simply to understand; I wish I had formulated that precisely. Well done!

J

[MrG]

Lovely, thank you all. It is as I'd hoped. So not crawling at under 40 km/h through a long block section without points until the next hauptsignal

I'm probably thinking of the UK's passing a signal at danger with authority. They can be sure that the route is locked into the correct position, but cannot assure there is another train in the section due to a failure of some kind, so proceed at caution as far as your line is clear. That is probably much closer to the use of a Zs 11 (?) I think; proceed using line of sight until the next signal, which might be rather torturous in a long block.

Thanks again, such a helping community.

Herr G

[halfur]

That is probably much closer to the use of a Zs 11 (?) I think; proceed using line of sight until the next signal, which might be rather torturous in a long block.

Exactly, although the current designation is Zs7, Zs11 was the designation in the Deutsche Reichsbahn (former East German railway). For Zs7 a few additional precautions apply as well, because (simplified) for those you have to drive on sight 400m beyond the next signal, because of the way German track vacancy detection systems are designed, the next vacancy detection block might begin a bit beyond the signal, so there might be a stopped train right behind the signal, which is basically invisible to the signal.

Well done!

Thank you very much, considering I'm just a hobbyist it's nice to get confirmation that my understanding seems to be correct

[Simon C]

I'm probably thinking of the UK's passing a signal at danger with authority. They can be sure that the route is locked into the correct position, but cannot assure there is another train in the section due to a failure of some kind, so proceed at caution as far as your line is clear. That is probably much closer to the use of a Zs 11 (?) I think; proceed using line of sight until the next signal, which might be rather torturous in a long block.

The German equivalent to it is called Zs 7 (proceed "on sight" until passing the next main signal + 400 m). You will encounter it on the Lehrte-Uelzen line where it is installed at every block signal between Celle and Uelzen - which can really challenge one's patience


Regards

Simon