Semaphores

[Kiha66]

Hello all, I realized I really have little idea of how semaphore signaling works, especially in regards to Japanese practice.  I grew up with entirely CTC and a few ABS signaling, so I dont have much knowledge of these older methods of movement control.  I have a kato kit with a few single and double semaphore heads which need assembly and painting, but I'm not sure how they should look or what the colors and positions mean, as well as how they should relate to the track work.  My current modules are JNR sometime around the 50s to the 70s, as a double track line in a rural area.  I also plan a station module at some point.  Are semaphores only found around stations, or are they also out on the main?  How should I paint and position them?  Any good reading to learn more?  (I also am interested in tablet signaling and other methods of train control)

[kvp]

First a few links:

http://www.sumidacrossing.org/Prototype/JapanSignaling/

https://en.wikipedia.org/wiki/Japanese_railway_signals

http://www.1999.co.jp/eng/search?typ1_c=104&cat=&state=&sold=0&sortid=0&searchkey=signal+mechanical&spage=1&Make=Tomix

http://www.tomytec.co.jp/tomix/report/n/nj_128.htm

 

Japanese form signals are pretty similar to japanese 2 and 3 aspect light signals, except block signals were practically non existent and all signals were operated manually using classic interlockings. There are some good guides about how to place and connect the Tomix working form signals. Basically you have the entry signals (red/green or red/yellow/green), the exit signals (red/green or red/yellow/green) and the distant signal (yellow/green).

[Kiha66]

9 hours ago, kvp said:

Japanese form signals are pretty similar to japanese 2 and 3 aspect light signals, except block signals were practically non existent and all signals were operated manually using classic interlockings. There are some good guides about how to place and connect the Tomix working form signals. Basically you have the entry signals (red/green or red/yellow/green), the exit signals (red/green or red/yellow/green) and the distant signal (yellow/green).

Thanks for these!  That Tomix diagram is very helpful.  So signals with a red board are stop/go, and signals with a yellow board are almost like yellow lights on colored signals, as they tell you the condition of the next signal?  Would there be any intermediate signals between stations, or would it just be one train at a time?  Would double track lines be signaled the same as single track lines?  Im assuming these are all manualy controlled, and safety is maintained by the different stations communicating?  This is very helpful. 

[Kiha66]

Another useful website I found, showing the types and some examples of use.  I remain slightly confused on poles that have two red aspects stacked however.
http://www.kihayuni.jp/SP/sp-udeki-1.html

[katoftw]

depends on the type of stacked one you are referring to.

 

the passing single with one red semaphore and the weird yellow shaped one.  the red is to allow you to pass that single, the yellow is to let you know the aspect of the upcoming departure single in advance

 

the semaphore with 2 red ones is for routes that aren't clearly defined.  example given is at a Y junction.

[kvp]

13 minutes ago, katoftw said:

the semaphore with 2 red ones is for routes that aren't clearly defined.  example given is at a Y junction.

I think a similar situation is when a modern mast has two light signals on it, one for each route.

[katoftw]

I generally agree, but depend how modern.  Current day you would see some form of proper indicator, but back in the 70s, yes to what you said.  But you might find some old school rural railway that hasn't updated their signalling in many decades still having something as you described.

[Kiha66]

49 minutes ago, katoftw said:

depends on the type of stacked one you are referring to.

 

the passing single with one red semaphore and the weird yellow shaped one.  the red is to allow you to pass that single, the yellow is to let you know the aspect of the upcoming departure single in advance

 

the semaphore with 2 red ones is for routes that aren't clearly defined.  example given is at a Y junction.

 

Yeah, the Red over yellow makes sense, as it allows trains to know that the station is clear (red) they can pass through without stopping (yellow).  The Red over Red seems to be diverging routes, but some also seem to be for two separate tracks on a double track line?  No idea which controls which.  Does Japan have a standard for which side a higher signal would control?

Edited March 22, 2018 by Kiha66

[NXCALE]

This is a very interesting topic. JPN signalling was originated from the British Signalling Practice so some ideas can be taken from the latter.

 

3 hours ago, Kiha66 said:

Yeah, the Red over yellow makes sense, as it allows trains to know that the station is clear (red) they can pass through without stopping (yellow). 

 

Red and yellow signals (TOMIX 5542) - red is the "home" signal of the station where the train is arriving. The yellow "passing" signal (of the TOMIX 5542) indicates the status of the next station (the second station is not shown in the TOMIX diagram, diagram #2 from the top). So the train can "pass" the first station at line speed and head towards the second station. I believe that this signal (TOMIX 5542) is used due to the lack of space between stations otherwise a "distant" signal (TOMIX 5546) would be used to indicate the status of the second station.

 

By the way, 

On ‎21‎/‎03‎/‎2018 at 5:09 PM, Kiha66 said:

Are semaphores only found around stations, or are they also out on the main? 

 

17 hours ago, Kiha66 said:

Would there be any intermediate signals between stations, or would it just be one train at a time? 

 

you can also add signals on the main (between stations or after an "exit" signal), these are called "Advanced Starting Signals". These are used to enable shunting movements or to allow trains to be held on the main line before being accepted in the next station. In that way, another coming train could enter to the first station (so we are able to increase line capacity, just a little bit). You could add more signals on the main (between stations) but bear in mind that these are mechanical signals so having a signal very far away from the signal box was tricky to control in those days.

 

Also,

17 hours ago, Kiha66 said:

 Would double track lines be signaled the same as single track lines? . 

yes, just remember that double track lines would be unidirectional (no bidirectional)

 

17 hours ago, Kiha66 said:

 Im assuming these are all manualy controlled, and safety is maintained by the different stations communicating?

yes, these signals were controlled by pulling levers from a signal box (a physically and mentally demanding job). Communication was maintained by using instruments (there a number of types) via a telegraph system.

 

3 hours ago, Kiha66 said:

The Red over Red seems to be diverging routes, but some also seem to be for two separate tracks on a double track line?  No idea which controls which.  Does Japan have a standard for which side a higher signal would control?

 

The taller red signal (TOMIX 5545) is used to indicate the status of the main line while the shorter red one (TOMIX 5544) is for sidetracks or branches (diverging junctions). For converging junctions, I believe both red signals should have the same high. I would also include distant signals (TOMIX 5546) for diverging and converging junctions.

 

As mentioned it before in other posts of this topic, the yellow or distant signal (TOMIX 5546) will show caution (downwards at 45 degrees) to the driver indicating that the next signal will be at stop.

In the British practice, there are also mechanical disc signals. These are used around stations for shunting movements or low speed (calling on) movements so maybe this type of signals were also used in Japan.

 

On ‎21‎/‎03‎/‎2018 at 5:09 PM, Kiha66 said:

Any good reading to learn more?

Quite long ago someone posted a link with books about the Japanese signalling practice and other related topics, I will hopefully find it again.  All that material was in Japanese but there were some interesting diagrams. Maybe, you could check some online info about the British practice as a starting point then move to the Japanese Practice.

 

Before I forget, it is a great idea adding signals to your modules!

 

[kvp]

1 hour ago, nxcale said:

I believe that this signal (TOMIX 5542) is used due to the lack of space between stations otherwise a "distant" signal (TOMIX 5546) would be used to indicate the status of the second station.

Not quite. They are usually used to indicate the next signal. So at an entry signal, the next signal is usually the exit signal. This means the next signal is within the current station. Only if they are used as an exit signal, then the yellow arm indicates the next signal, which would be the entry signal of the next station or the next signal station.

 

For block operation with mechanical signals, a signal station was used and this could be as little as a tower with two signals. (one for each direction) Many times, these were combined with crossing gates, so one person could operate both and the signals could also provide a protected crossing. Currently in use (but fully automated) signal station examples could be found on the Hakone-Tozan line, where the switchbacks mean they could not be eliminated or replaced and one example on the Enoden, where the single track line has two bypass tracks between stops. All of these are now automated with block signalling logic.

[marknewton]

19 hours ago, Kiha66 said:

Would there be any intermediate signals between stations, or would it just be one train at a time?  Would double track lines be signaled the same as single track lines?  Im assuming these are all manualy controlled, and safety is maintained by the different stations communicating?  This is very helpful. 

 

If the section of single line uses token or staff block working, then there is no requirement for intermediate signals between interlockings. However there were some single and double lines that used a form of automatic block working controlled by track circuited, powered upper quadrant semaphores, in which case you would see intermediate signals between interlockings. 

 

Double track lines were generally signalled for unidirectional running, i.e. an Up track and a Down track. The usual method of control or "safeworking" on double lines was block telegraph in the early days. That was superseded by automatic block or CTC, both of which could employ intermediate signals. Manual control of interlockings was common, but in more modern times individual signal boxes have been replaced by remote signalling complexes. There are also stretches of double track signalled for bidirectional running, which feature half-pilot staffs for emergencies or degraded conditions.

 

Theres some interesting material on this website:

 

http://www.lazyjack.co.jp/home/non.php

 

There's a large number of track and signalling diagrams on this blog:

 

http://senrohaisenzu.cocolog-nifty.com/blog/

 

Cheers,

 

Mark.

Edited March 22, 2018 by marknewton

[NXCALE]

6 hours ago, kvp said:

Not quite. They are usually used to indicate the next signal. So at an entry signal, the next signal is usually the exit signal. This means the next signal is within the current station. Only if they are used as an exit signal, then the yellow arm indicates the next signal, which would be the entry signal of the next station or the next signal station.

 

Yes, I see the point. To provide a little more info, the use of a "distant / passing" (or yellow) signal is different than other signals. 

 

In the BR (British Railway) practice, a "distant / passing" signal is used to provide a warning to the driver about the "home", "starting" (also called as "exit") and advanced starting signals controlled from the same signal box.  That is, a yellow mechanical signal doesnt only indicate the status of the next (home / start) signal.

 

Also a "distant" signal can be passed when the signal is "caution" which is not applicable to red signals. When the "distant" signal (only a yellow signal placed at X00 meters from the home signal, not the red over yellow signal) shows "caution" means that the driver must reduce speed and be prepared to stop and the home/start signal of that station.

 

In the interlocking, a "distant" signal can be only set as "proceed" if the home and starting signals are set as "proceed" which basically means that a train can move as far as the "home" signal of the next station.

 

Bear in mind that the above is from the mechanical BR practice so the Japanese practice could be different.

 

 

 

[katoftw]

48 minutes ago, nxcale said:

 

Yes, I see the point. To provide a little more info, the use of a "distant / passing" (or yellow) signal is different than other signals. 

 

In the BR (British Railway) practice, a "distant / passing" signal is used to provide a warning to the driver about the "home", "starting" (also called as "exit") and advanced starting signals controlled from the same signal box.  That is, a yellow mechanical signal doesnt only indicate the status of the next (home / start) signal.

 

Also a "distant" signal can be passed when the signal is "caution" which is not applicable to red signals. When the "distant" signal (only a yellow signal placed at X00 meters from the home signal, not the red over yellow signal) shows "caution" means that the driver must reduce speed and be prepared to stop and the home/start signal of that station.

 

In the interlocking, a "distant" signal can be only set as "proceed" if the home and starting signals are set as "proceed" which basically means that a train can move as far as the "home" signal of the next station.

 

Bear in mind that the above is from the mechanical BR practice so the Japanese practice could be different.

 

 

 

Nope. You are confusing the distance and passing signals. While they do a similar job...

 

The passing signal is mostly attached to the home signal and 'only' shows a relation to the starter/exit signal off the platform/yard.

 

The distant signal can be in advance of any signal that has poor sighting visability eg after tunnel or around sharp curve. Normally in single track bi-directional running, this would be the home signal.

 

They could've been the same thing. But for some reason in Japan they had slight differences. Hence the shapes of the arms.

 

In todays world of coloured light signals.  You just number the signal and you have coloued light repeater or beacon in advance doing the same jobs.

Edited March 22, 2018 by katoftw

[NXCALE]

Yes, well mentioned it. Actually what I described before (rules, interlocking, etc) is correct but is only aplicable for "distant" signals for the BR practice.

I think that "pass" signals are not used in the BR practice or at least, I havent seen (or I dont remember) a case.

It would be nice to find a source with the rules for JPN  "pass" signals but it would be probably in Japanese.

 

What you mentioned about visibility is correct and now with light signals, these are the "reperaters". The ones with only 2 aspects and the "R" on it (not JPN practice, repeaters are different in JPN).

Also in today's world, there are railway companies that are moving away from signals and going towards CBTC and ETCS. So probaly we will not see many signals in the future.

[kvp]

47 minutes ago, katoftw said:

 

They could've been the same thing. But for some reason in Japan they had slight differences. Hence the shapes of the arms.

The reason is that the passing signal arm is always overridden by the main signal arm while the distance signal is a standalone signal that could be passed. Essentially the 2 arms (red/yellow) signal could show go/slow/stop while the distance signal is only go/slow and can't show stop. This is fully in line with old german and austro-hungarian practice.

 

The color signal world has brought the US style repeaters and the european style vertical color heads. (and for some time even US style single lens searchlights were in use)

 

The single red form signal is green/red in color signal terms, the two arm one (red/yellow) is green/yellow/red in color lights while the single yellow arm is green/yellow as color lights.

 

PS: The japanese two arm form signals seem to show two blue lights for a green aspect and blue+yellow lights for a yellow aspect. Red is shown as red+yellow. Red+blue seems to be illegal.

[NXCALE]

19 minutes ago, kvp said:

Essentially the 2 arms (red/yellow) signal could show go/slow/stop while the distance signal is only go/slow and can't show stop. This is fully in line with old german and austro-hungarian practice.

It makes sense. Also, I think that maybe there are more reasons for the use of pass signals. 

 

In the TOMIX diagrams (#2,4,7,8 from http://www.tomytec.co.jp/tomix/report/n/nj_128.htm), distant and pass signals are used.  However, using a pass signal to slow an arriving train could be done with a distant signal (for a home signal). In that arragement (with the distances shown and putting a speed line), having a pass signal only improves the line capacity just a bit (maybe just 30 seconds or less, just to say a number). 

 

So having that minor improvement maybe it could not justify the installation and maintenance of a mechanical signal.

[Kiha66]

Lots of interesting discussion!  Perhaps a reason for the use of both distant and passing signals is when a train would pass through a switch to another platform.  In this case the distant signal would give the train warning to slow down so it would not be taking the diverging route at speed, which would be separate from the warning the passing signal wold give for if the train would have to stop at the platform.   Also for token exchange, if the token was not ready the passing signal could alert the driver of the need to stop.

[NXCALE]

28 minutes ago, Kiha66 said:

Lots of interesting discussion!  Perhaps a reason for the use of both distant and passing signals is when a train would pass through a switch to another platform.  In this case the distant signal would give the train warning to slow down so it would not be taking the diverging route at speed, which would be separate from the warning the passing signal wold give for if the train would have to stop at the platform.   Also for token exchange, if the token was not ready the passing signal could alert the driver of the need to stop.

 

I think we are getting there.

The TOMIX diagrams dont show it well but some turnouts (points) must be low-speed ones. In the case of non JPN ligth signals, there could be a signal showing a green aspect and a route indicator. In this case, the driver knows that he/she needs to reduce the speed before passing the turnout. But also, a signal could show a yellow aspect and a route indicator to limit the train speed even further (this because the geometry of the coming turnout). So a distant signal could work as per BR practice and maybe could the pass signal indicate that the train will pass a low-speed turnout? or viceversa? I think it will be clear if we get a JPN layout example using only distance signals without pass signals (maybe this goes against the rules that we dont know).

 

[Kiha66]

3 minutes ago, nxcale said:

I think we are getting there.

The TOMIX diagrams dont show it well but some turnouts (points) must be low-speed ones. In the case of non JPN ligth signals, there could be a signal showing a green aspect and a route indicator. In this case, the driver knows that he/she needs to reduce the speed before passing the turnout. But also, a signal could show a yellow aspect and a route indicator to limit the train speed even further (this because the geometry of the coming turnout). So a distant signal could work as per BR practice and maybe could the pass signal indicate that the train will pass a low-speed turnout? or viceversa? I think it will be clear if we get a JPN layout example using only distance signals without pass signals (maybe this goes against the rules that we dont know).

 

Yeah, it seems the basics aren't too complicated assuming the train has only one possible track.  The first type seem to be Home (station entrance), and starting (leaving the station) use red/blue lights with red paddle.  These are stop or go and are absolute unless otherwise noted.  The other main type is the distant (approaching the station, warning of the condition of the home signal) and passing (seen when entering the station, warning of the condition of the starting signal).  These have yellow paddle with a yellow/blue light.  Red paddles have a black stripe 3/4 of the way down the paddle, while yellow paddles have a white stripe in the same place.  Red signals are square on the ends, distant have a triangle shaped cut taken out of the end (swallow tail) and passing have a flare widening out the end of the signal.  All only control in one direction, the reverse side is white with a black stripe 3/4 of the way to the end.  

[Kiha66]

If a non-main line line branches to the right side of the main line, the signal controlling the branch line can be placed on the same pole as the signal controlling the main line, but below the main line signal.  According to JNR, up to three signals can be on the same pole.  When the non-main line branches to the left of the main line, it should be installed on a separate pole to the left of the main line signal, lower than the main line signal by one spacing.  

Edited March 23, 2018 by Kiha66

[Kiha66]

What I am still confused on is when a signal also controls access to a switch, for example this starting signal arrangement at Imari station, where each line goes though a set of switches to serve either the Matsuura line towards sasebo, or the other line towards Arita.   The photo at the bottom of the page is what is confusing me.  Would both routes get a separate signal, or is there one signal to tell the driver the route that has been set is clear?  If so what is the purpose of the second red signal on each pole?
http://www.lazyjack.co.jp/home/non.php?catid=31&page_4.html

[katoftw]

The lower red one on the right is for a diverging track to the right.

 

The taller passing signal has been well explained. For straight ahead.

Edited March 23, 2018 by katoftw

[katoftw]

kvp already posted this link in an earlier post.

 

http://www.tomytec.co.jp/tomix/report/n/nj_128.htm

 

The first two diagrams actually have a video of the semaphores in use with moving trains.  It is a great example of all with have been discussing.

[NXCALE]

Hi Kiha66. How does your layout plan looks like (or idea of layout)? I think that could help to understand better the type/number/location of signals.

[Kiha66]

18 hours ago, nxcale said:

Hi Kiha66. How does your layout plan looks like (or idea of layout)? I think that could help to understand better the type/number/location of signals.

 

Thanks nxcale!  I'll try to mock up a diagram when I get home in a few hours.