DG entry signal indicators

[jiklobka]

What do these indicators with arrows mean, pls?

[Thistle Whistle]

Interesting question!  According to the page linked below, they are Restricted Braking Distance indicators.  Presumably to signify a specific braking distance, but I don't know the details.

Could they be related to the pedestrian crossing at the end of the station platform to help prevent overshoots or perhaps something to do with the short signal block, maybe?

It looks like there is also a 3rd sign in this category which is specific to freight trains. Hopefully someone more knowledgeable will be along to help soon!

Marked W19 and W20 in the image...

http://pkprepo.net/railway-signs-of-polish-railways/

Edited December 28, 2022 by Thistle Whistle
missing words!

[Schyrsivochter]

 

There is an additional main signal D positioned before the platform in Dąbrowa Górnicza. For a full-speed route from entry signal P (the one in the picture above) passing through D up to the exit signal C2, the overlap crosses the pedestrian level crossing. For a route from P to D, that’s not the case. However, since the distance from P to D is quite low, a lower speed must be signalled at P so that all trains can safely stop at D. This is what you’re seeing in the picture.

A good dispatcher, of course, closes the level crossing and sets an additional route from D to C2 when a train approaches, so that the signal box upgrades the indication at P to full speed and a train can enter the station without unnecessarily slowing down beforehand.

To be honest, what I as a frequent DG dispatcher would like would be that I could choose a shorter overlap behind C2, with a 40 km/h restriction at D. I know German computer-based interlockings often allow choosing different overlaps, automatically signalling lower speeds for shorter overlaps as necessary. I’m not sure if the real Dąbrowa Górnicza signalling can do this, but if I recall correctly, D actually has five lights, so it could show a 40 km/h restriction.

 

 

[SurvivorSean]

Yeah what your talking about I believe is called stacking (I could be wrong).  But stacking involves a route that is set to clear immediately once the block is unoccupied.  But I may have read that wrong.

To stay on the topic at SG I will often bring a train that doesn't stop onto the opposite track when available just to give an approaching train more room before requiring a stop.  By the time the train in front makes it's stop and leaves the other train usually has at least 1 block on exit and can cross back over.

Thanks

Sean

[Schyrsivochter]

I just played a train and … I first got signalled upcoming 40 km/h at the last block signal before P, then while I was approaching, that aspect upgraded to full speed at P but 40 km/h at D … And I have no idea what the dispatcher did, and I wasn’t able to get an answer out of them how they managed it. And also I don’t know if the overlap was actually reduced or not.

I wonder if it’s the difference between a) setting a route P–D, then D–C2, or b) setting a route directly P–C2 via D (clicking on the signals in that order)? I thought that must’ve been identical, with the signal indications automatically upgraded to the ‘fastest’ possible? Or does the former do the 40 km/h at D thing and the latter switches D off or turns it into a distant signal repeater or something?

Or maybe the last time I was driving there, C2 was already cleared, so both P and D showed clear and I hadn’t yet had a chance to see the signalling when C2 shows stop?

Next time I’m playing DG dispatcher, I might just try out a few options and ask players what signals they’re getting. I would really love to know how these signals behave.

[Skully]

There is more information on http://jareks.zonk.pl/signal/signs.htm

This might explain what happened to me as I approached a 100 km/h restriction immediately followed by a 40 km/h at short distance. If I had known these signs I would have put on more brakes. 😁

[Thistle Whistle]

47 minutes ago, Skully said:

There is more information on http://jareks.zonk.pl/signal/signs.htm

This might explain what happened to me as I approached a 100 km/h restriction immediately followed by a 40 km/h at short distance. If I had known these signs I would have put on more brakes. 😁

Ah, another great reference there, thank you.  And that site explains things more fully.

Pleased that one of my guesses was indeed correct.  And thanks to the amazing job done designing this route, I was actually answering completely by memory.

Having since driven the section, I've also spotted there is indeed the single double arrow sign on the following signal (the one with the short block).

[stronzio]

Dabrowa has some mandatory overlap distance after signal C2, the first grade crossing after the signal falls directly into it so it has to be closed or you can't set signal D to open.

If you do so, you can notice that the crossing gets "blocked" (yellow track section on it), signal P will show "expect 40" (I think paired with an "execute 100" in the same place, and a relative "expect 100" beforehand, but I can't remember exactly rn) and signal D will show an "execute 40 speed restriction" aspects respectively.

If you open C2, all signals will "upgrade" to "clear" (green). Signals D and C2 are extremely close so they lower maximum speed through signalling in accordance with available braking distance; I didn't think they did this in Poland, though it's extremely common in other places (I.e. Switzerland)

I have a feeling that Poland seems more "liberal" when it comes to overlap distances, esp. when confronted with Germany or other places, but I noticed that Sosnowiec glowny also has at least one route with a simulated overlap, here:

Edited December 30, 2022 by stronzio