single track signals

martinvk

since 10 Aug 2002
Usually I place double mainline track so signalling is pretty easy with each direction on its own track with its own signals.

Recently I started modelling a single track route which brings me to a signalling issue.
At intervals along the track I have passing sidings with direction marks and appropriate signals. The problem is the last signal at the exit of one siding declares the track ahead is un-signaled and stays at red, stopping AI trains. The sidings are at prototypical distances apart so it doesn't see the signal at the entrance of the next siding. If I add signals in between the sidings, what is to prevent corn-field meets? Adding extra sidings will not be prototypical for the route. Is there a Trainz solution?
 
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In the past, people would add in an invisible junction somewhere to break up the long stretches. I remember this being mentioned in the old forums, so that would be in 2005 probably. The other solution, while not prototypical for your route, is to use an invisible signal. Given that signals today, or at least those by Jointed Rail are, placing in between invisible signals shouldn't be a problem. This may be an issue if these signals aren't "intelligent" as they will blindly let opposing traffic through.
 
There are several possibilities.


  • Using Track Triggers with Session Rules to control traffic flow. The triggers, which have to be carefully placed, can be used to control signals and track switches that allow entry to the single track section.
  • Using EITs to set paths through the single track section. EITs, with their associated Rules and Driver Commands, do have a learning curve.

But no automated solution will be perfect, not even in the real world of railroading where human supervision and intervention are still required.
 
I run a few branch lines with single line workings and have no problems with the standard control features without resorting to extensive use of other later addon's.
Here one must bear in mind that a majority of single line workings, in the UK, have scheduled passenger and goods movements, this generally does not lead to clashes on the lines.
A majority of station stops are also provided with goods sidings and sometimes passing loops.
Distant and home signals at each station up and down lines generally prevent clashes.
Also where distance is generally greater that 1-3 mile an intermediate combined signal could be appropriate.
There are also token controls available to apply where these were applied in real life.
My moto is keep it simple, utilize a minimum of track marks and wait commands only when necessary.
 
I wonder if a bunch of invisible passing sidings at the maximum separation distance would do the trick? The AI would be satisfied and as long as I don't see the opposing consist going around the other consist, it didn't happen. Right now I have passing sidings and stations spaced from 4 km to 40 km with an average of 29 km between them. Without testing, what is the maximum distance before an un-signaled track warning is provoked?
 
I wonder if a bunch of invisible passing sidings at the maximum separation distance would do the trick? The AI would be satisfied and as long as I don't see the opposing consist going around the other consist, it didn't happen. Right now I have passing sidings and stations spaced from 4 km to 40 km with an average of 29 km between them. Without testing, what is the maximum distance before an un-signaled track warning is provoked?

Invisible passing sidings will give the AI some weird ideas and they'll take trips on the dirt. I know because I did that once when attempting to setup a diamond crossing before the ASB controller was developed. It was amusing watching the AI switch the lever then go down the dirt and get stuck.

What might work is setting up some levers with a short invisible lead. You can then put in an invisible signal there and the junctions will act as breaks in the line.
 
Hmm, is the maximum distance to the next signal a fixed amount or is there some calculation involved?
 
Hmm, is the maximum distance to the next signal a fixed amount or is there some calculation involved?

It seems to be around seven miles, probably 10 Km, judging by what the HUD reports, e.g. "Next Signal - - . -" Even on my 30-mile Fond Du Lac branch there are one or two gaps like that, even though the Milwaukee tried to put a passing track every five miles.

There's nothing wrong with putting in intermediate permissive signals, many roads do. Probably be wise to have one each way. Make them invisible signals if you prefer.

:B~)
 
It seems to be around seven miles, probably 10 Km, judging by what the HUD reports, e.g. "Next Signal - - . -" Even on my 30-mile Fond Du Lac branch there are one or two gaps like that, even though the Milwaukee tried to put a passing track every five miles.

There's nothing wrong with putting in intermediate permissive signals, many roads do. Probably be wise to have one each way. Make them invisible signals if you prefer.

:B~)
Thanks for the info. I'm not against putting in intermediate permissive signals but then the AI will allow consists in the single track while an opposing consist is also entering at the other end.

What I need is a way to create a logical block that contains several physical blocks. If any one of the physical blocks is occupied, the logical block will report it is occupied and thus prevent an opposing consist from entering from the opposite end of a single track. Is this possible?
 
It seems to be around seven miles, probably 10 Km, judging by what the HUD reports, e.g. "Next Signal - - . -" Even on my 30-mile Fond Du Lac branch there are one or two gaps like that, even though the Milwaukee tried to put a passing track every five miles.

There's nothing wrong with putting in intermediate permissive signals, many roads do. Probably be wise to have one each way. Make them invisible signals if you prefer.

:B~)

Hard numbers (doped out last night):

~7.7 miles = ~12.4 Km

:B~)
 
Use EIT to control your track as only one train can be on the path at the same time.
After several long conversations with PGuy, I started to experiment with using EIT to set exclusive paths each way between passing sidings. Even with several blocks between sidings, the next opposite consist will not enter the single track until the path is clear, exactly what I need to happen. Have to use multiple blocks because of the limit on how far apart signals can be placed until they report an un-signaled track beyond the next signal. The EIT path doesn't appear to be restricted in the same way. Testing continues, ...
 
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