Speed Limit (ZS3 and ZS3V) signals: Am I doing this right? // Geschwindigkeitsbegrenzungssignale (ZS3 und ZS3V): Mache ich es richtig?

[simonjackson1964]

A simple block signal with a mounted distant signal, a ZS3 speed limit signal that allows 120kmh (72mph) and a ZS3V signal that says 80kmh (48mph) if the following signal is red. The limit on the ZS3V supersedes the ZS3, if I understand correctly? Like this:

Ein einfaches Blocksignal mit montiertem Vorsignal, ein ZS3-Geschwindigkeitsbegrenzungssignal, das 120 km/h (72 mph) erlaubt, und ein ZS3V-Signal, das 80 km/h (48 mph) anzeigt, wenn das folgende Signal rot ist. Die Begrenzung auf die ZS3V ersetzt die ZS3, wenn ich das richtig verstehe? So was:

I'm reasonably sure that's correct. While the main signal is displaying "stop" both the speed indicators are out, as the speed is zero by default. (The distant signal is also out.)

When the main signal goes green, the distant signal lights up. If it is showing "Expect Stop", we need the train to travel more slowly so that it doesn't shoot past the next signal, so the ZS3V lights, displaying "8" for 80 kmh, but the ZS3 remains dark. Then when the distant signal changes to "Expect Go", the ZS3V goes out and the ZS3 lights up with "12" for 120 kmh.

Ich bin ziemlich sicher, dass das stimmt. Während das Hauptsignal „Halt“ anzeigt, sind beide Geschwindigkeitsanzeigen aus, da die Geschwindigkeit standardmäßig Null ist. (Das Vorsignal ist ebenfalls aus.)

Wenn das Hauptsignal grün wird, leuchtet das Vorsignal. Wenn es "Halt erwarten" anzeigt, müssen wir den Zug langsamer fahren, damit er nicht am nächsten Signal vorbeischießt, also leuchtet die ZS3V und zeigt "8" für 80 kmh an, aber die ZS3 bleibt dunkel. Wenn dann das Vorsignal auf „Expect Go“ wechselt, erlischt die ZS3V und die ZS3 leuchtet mit „12“ für 120 kmh.

 

[Sintbert]

That is wrong.
The ZS3 together with the signal shows what ist to do at the current location.
The ZS3v together with the distantsignal shows what is to do at the next signal location.
Usually the distant is in braking distance to its mainsignal on linespeed. Trains that cant satisfy this requirement have to drive at lower speeds.

ZS3 ist often not used to slow down the train to a stop, but to give a speedlimit for turnouts.
A gradual slowdown is only required when you don't have braking distance between signal.

When you want to realize a gradual slowdown from lets say 160km/h then i would do something like this:

1. Mainsignal green, ZS3 dark, distant green, ZS3v showing 12 - Driver will start to slow down to 120km/h for the next signal.
2. Mainsignal green, ZS3 showing 12, distant red, ZS3v dark- Driver will slow down to below 80km/h within 20s to satisfy PZB, then continue to slow down, prepared to stop on next signal.
3. Mainsignal red, ZS3 dark, distant dark, ZS3v dark- Driver stops ahead of signal.

Even more gradual would be:

1. Mainsignal green, ZS3 dark, distant green, ZS3v showing 12 - Driver will start to slow down to 120km/h for the next signal.
2. Mainsignal green, ZS3 showing 12, distant green, ZS3v 8 - Driver will slow down to below 80km/h within 20s to satisfy PZB.
3. Mainsignal green, ZS3 showing 8, distant red, ZS3v dark - Driver will slow down, prepared to stop on next signal.
3. Mainsignal red, ZS3 dark, distant dark, ZS3v dark- Driver stops ahead of signal.

I hope this helps.

Regards
Sintbert

 

[simonjackson1964]

Ah, right. Thanks

So in the situation I was describing, with signal A and signal B, and a track speed of 120kmh, the ZS3V is unnecessary.

Signal A green and signal B red has the advance signal on A show yellow, and the ZS3 show 8 as per point 3 in your second example, where if both A and B are green The advance signal on A is green and the ZS3 is dark as the track speed doesn't need to be displayed?

From what you're saying in the above examples, it seems to me that the ZS3V acts a bit like the UK block signals with two yellow lights

The ZS3V on a green light is basically saying that the next light is going to have a yellow advance signal, the equivalent of two yellows in Britain.

[Sintbert]

Not at all.. It is not based in progression like the UK signaling.

The Basic Signal is just Green/Red. And the basic signaling is just:

G    G      R
|       |       |
------------...

Then you have the distant signal:

G       G        R
G       R        -
|          |        |
--------------

The ZS3 only gives the current signal a different speedlimit from the trackspeed or displayed speed

And the ZS3V only shows what the ZS3 on the next signal shows.

 

It is always only the state of the current signal, showed by the mainsignal and ZS3, and below the state of the next signal, showed by the distant and ZS3V.

Anything different from Green/Red was originally only shown, when a turnout has a lower than linespeed limit. Example: for strait, its green, for turnout its green&yellow (40km/h).
Then the ZS3 can be used when the turnout allows as example 60km/h. The Signal would show green&yellow and the ZS3 6 for 60km/h instead of the signaled 40km/h

 

Bearbeitet 25. Januar 2022 von Sintbert

[Sintbert]

So, now that i had the time:

This is what your down progression would look like.

The first signal gets approached at linespeed 120km/h, tells the driver to slow down to 80km bevor the next signal.
The second signal gets approached at 80km/h, tells the driver to limit his speed to 80km/h and the red distant tells him to slow down to below 40km/h or drive on sight (what ever is lower depending on track visibility)

BUT: The distance between each of those signals is enough for the train to stop from linespeed bevor the next signal. Usually 1km.
Such setup is rare and only used on lines with very high amounts of trains to get them moving along a bit more fluent. Like between a mergepoint of multiple lines and a big station, when there aren't enough running lines.

OR: They use the more modern Ks-System, but that works quite different from the 69-system.

Regards
Sintbert

Bearbeitet 25. Januar 2022 von Sintbert

[simonjackson1964]

I've yet to find a decent explanation of the KS system which is why I'm using the 69 system!

But, what you describe above is pretty much the same as the "two yellow" system in the UK. Again, it's only used ion really busy tracks where they want to keep things moving, most of the lines leading into London use it.

A single green light means track clear proceed at track speed. A twin yellow means line clear but slow to reduced speed before the next signal. A single yellow means slow to zero before the next signal. Obviously, red means stop.

So a 69 light showing HP1 with a green advance and a lit ZS3 V is effectively the same as two yellows in the UK...

Most rural lines have just red/green lights. Slightly busier lines will have a single yellow between them, like upside down traffic lights.

[Sintbert]

The difference being, that the lines into London have their signals so close together, that you need multiple signal distances to slow down from line speed to stop. With the 69 System that is not the case. You have enough space between each signal to stop from line speed. Even in areas where such a progression system is used, it is purely done to get a more regular flow of trains.

Purely for technical reasons with the PZB safetsystem you have to put signals in certain distances to each other for it to work correctly.

[simonjackson1964]

Another question, related but different

An advance signal displays whatever is shown on the next main signal. The reason the advance signals are blanked when mounted on a main signal that is red is obviously to avoid confusion in the event that the following signal is green.

But what of a free standing advance signal? It can't be blank when the signal before it is red, because that would happen when there is a train approaching it. But after the train goes past, if the next signal id green, does it continue to display green? To turn it red as the train passes, at least the way I have them set up with a straight connection to the main signal, would also turn the main signal red.

The obvious solution would be to blank the advance signal as the train passes (using the animation) then un-blank it either when the preceding signal goes green, or a train enters the block (the latter would probably be easier) or the "Route" is activated.

I can figure out how to do all three of the above, but what I really want to know is: Is it necessary? Do the free-standing advance signals change as a train goes past? Or do they continue to display what the following signal displays, even though they are technically inviting another train into an occupied block?

[Goetz]

vor 10 Minuten schrieb simonjackson1964:

after the train goes past, if the next signal id green, does it continue to display green?

Yes, it does. It always copies the related main signal.

Confusion is impossible in this case, because no further train can enter this section until the current train has passed the maIn signal and vacated the block.

Kind regards
Goetz

 

Bearbeitet 27. Januar 2022 von Goetz
typos

[simonjackson1964]

Thank you, Goetz

That saves me some programming