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Colour or semaphoresignals?

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  • Member since
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  • From: CSXT/B&O Flora IL
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Posted by waltersrails on Thursday, March 30, 2006 12:06 PM
both to me
I like NS but CSX has the B&O.
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Posted by cefinkjr on Monday, March 27, 2006 10:08 AM
QUOTE: Originally posted by BR60103

I have been on commuter trains which have stopped a train length or so up the wrong branch.


Wonder what the dispatcher is now doing for a living.

Chuck
Allen, TX

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Posted by BR60103 on Sunday, March 26, 2006 9:35 PM
I have been on commuter trains which have stopped a train length or so up the wrong branch. There is then a complicated procedure as the train has to clear the block that contains the turnout before the signals can be reset for it to back up.

--David

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Posted by cefinkjr on Saturday, March 25, 2006 6:14 PM
QUOTE: Originally posted by JimValle

...trains ... seem to run through most signals without even slowing down, like a red over red over yellow.


On the former New York Central and the Penn Central, Red over Red over Yellow (the appearance or aspect) was Approach Slow (the indication). The meaning was "approach the next signal prepared to stop; not exceeding slow speed through the interlocking". (Yes, my job required me to memorize this information.) Slow speed was 15 mph or slower if necessary to be able to stop within the range of sight depending on weather conditions.

"Speed through the interlocking", by the way, meant that the speed restriction applied to the entire train and the entire length of the interlocking. Flogging the horses as soon as they passed the far end of the interlocking would get you suspended if not fired.

Note that there is nothing in the definition of this signal indication (or any other on the NYC/PC) about route. As Nick indicated in an earlier post, "North American railroads use speed signalling, rather then route signaling."

Chuck

Chuck
Allen, TX

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Posted by cefinkjr on Saturday, March 25, 2006 6:03 PM
QUOTE: Originally posted by David Foster

how does the crew see the number plate (or lack of it) at night when rolling?


In every case where I saw a number plate indicating a permissive signal, the number plate was black and the numbers (6" or so high) were an appropriate arrangement of glass reflectors. In many cases, the numbers were also paint white against the black background with the glass reflectors in the white area. I expect these have all been replaced with some sort of "ScotchLite" reflective numbers; cheaper and probably more visible.

Chuck

Chuck
Allen, TX

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Posted by Don Gibson on Saturday, March 25, 2006 5:39 PM
Semaphors will be twice as expensive as Searchlite's because of mechanical nature. (Indicatior + motor + Software actuator + detector) Plus 2 per block for Bi-direction.

http://www.tomarindustries.com/H-854.jpg
http://www.oregonrail.com/117-118.jpg
Don Gibson .............. ________ _______ I I__()____||__| ||||| I / I ((|__|----------| | |||||||||| I ______ I // o--O O O O-----o o OO-------OO ###########################
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Posted by nbrodar on Friday, March 24, 2006 11:03 PM
QUOTE: Originally posted by David Foster

how does the crew see the number plate (or lack of it) at night when rolling?


That's why you have to be qualified on the territory. The last time I qualified, I had to know the location, and name of every signal, and wether it was absolute or permissive. I also had to know the name, and location of every road crossing, the maxiumum authorized speed and special restictions for each milepost, the length of every siding, the location and type of each defect detector, and the location of any industry tracks off the main.

BTW
Red - Red - Yellow is a Restricting Signal, and can be applied to any route through an interlocking.
Red - Green is a Medium Clear, which simply states a train must proceed at medium speed until clear of all switches. It does not necessarily mean you are making a diverging movement.

Nick

Take a Ride on the Reading with the: Reading Company Technical & Historical Society http://www.readingrailroad.org/

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Posted by BR60103 on Friday, March 24, 2006 11:02 PM
I posted copies of pages from the old Canadian rule book on another forum. I check for the link.
Canadian procedure seems to be speed limiting, with no route indications. When you take up to 3 head, with 3 colours and possibly flashing, there are a lot of indications.
Example: rule 414 "limited to slow" red over flashing green over flashing yellow. "Proceed, limited speed passing signal and through turnouts, approaching next signal at slow speed." I suspect that when you know the line, the limited speed through turnouts tells you which direction you're going.
The red/red/yellow mentioned above is, in Canada, rule 426 "restricting signal" proceed at restricted speed. The book shows 9 different signal that mean the same, starting with a red and an "R" plate. One red light is "stop and proceed"; a red light with and "A" plate is "Stop".

--David

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Posted by Anonymous on Friday, March 24, 2006 4:27 PM
Hi Trainfellows!
Thanks for all the answers!
I shall take a visit on some links you did gave to me.I see forward to learn something!

agge [:D]
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Posted by wjstix on Friday, March 24, 2006 4:17 PM
BTW about block signals - railroads have had different ways to say whether you really have to stop at a signal or not. Using a numberplate to indicate it is one way. Some railroads have a large circular sign with "P" (for permissive) or "A" (for absolute) - permissive meaning you can go thru a red at reduced speed, absolute meaning you absolutely have to stop. Some only marked one - so for example, unless there is a "P" for permissive on the signal, it's an absolute stop signal.

With semaphores, it could be done with the shape of (and markings on) the semaphore blades.

A lot of these subleties are probably not as important now with radios two-way communication etc.
Stix
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Posted by wjstix on Friday, March 24, 2006 4:09 PM
Generally one headed signals are block signals - telling you the track ahead is clear for two blocks (green) one block (yellow) or the block ahead of you is occupied (red). Two or more heads means it's an interlocking signal. Interlocking signals are used where two (or more) rail lines cross at grade level, or where one rail line (or more) branches off from the other. In other words, interlocking signals help you know where you're going, block signals tell you if the way is clear - and how fast you can get there.

Let's say you're in the cab of a locomotive with a train barreling down the mainline. Ahead of you is a place where a branchline turns off the mainline to the left at a turnout. As you get close to the switch, you'll see a two-headed signal. The top signal is for the mainline, the bottom one for the diverging branchline route.

So if the top light is green and the bottom one is red, you're going to keep going full speed on the mainline.

If the top one is red, and the lower one green, you're going onto the branchline.

If the signal is red over red you have to STOP RIGHT NOW and not go past the signal. Unlike block signals where you sometimes can go thru on red at a very reduced speed, an interlocking stop signal always means STOP.

If there were two diverging routes from the mainline, you'd have a three headed signal, with the top head for the mainline, the middle one for the next most important diverging track, and the lower one for the lesser diverging line (like an interchange track for example).

Like with other signals, yellow is used to indicate you need to slow down, so your "red-over-red-over-yellow" signal means "proceed slowly thru secondary diverging track prepared to stop".
Stix
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Posted by JimValle on Friday, March 24, 2006 3:19 PM
I know about stop, approach and proceed but one thing stumps me. When I'm actually watching trains run, like on the AMTRAK corridor, they seem to run through most signals without even slowing down, like a red over red over yellow. I guess the practice is that trains are running on very short headways so this seemingly very restrictive signal simply means that the engineer should remember that there's a section ahead of him/her to watch out for. Am I right about this?
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Posted by Anonymous on Friday, March 24, 2006 2:08 PM
Terrific responses , especially the reminder that the US uses speed signalling rather than the route signalling that I'm used to ( it's a bit like a foriegn language to me).
how does the crew see the number plate (or lack of it) at night when rolling?

Great web sites

THANKS ALL!
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Posted by sbouchey on Friday, March 24, 2006 6:56 AM
Some information sites:
http://home.comcast.net/%7Ecandcb1/idx3_pl.html
http://www.lundsten.dk/us_signaling/index.html
http://broadway.pennsyrr.com/Rail/Prr/
http://www.railroadsignals.us/
Some of these have links to other sites.
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Posted by jimrice4449 on Thursday, March 23, 2006 11:16 PM
nbrodar covers it succinctly and pretty completely. The speed for "aproach" can vary from road to road. Most I've worked on used 40mph. The difference between 'STOP & Stay" (absolute) and stop & proceed at restricted speed (now more generally "pass and proceed to next signal not exceeding restricted speed) is that the absolute signal doesn't have a number plate. The presence of a number plate makes the signal"permissive". There's also another frequently found aspect, flasshing yellow, which is "aproach medium" and indicates that the next signal displays aproach.
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Posted by nbrodar on Thursday, March 23, 2006 10:44 PM
While the aspect (arrangment of lights) varies from railroad to railroad the indication (meaning of the signal) is constant. It's also good to note, that North American railroads use speed signalling, rather then route signaling. NA signals give the speed permitted, and from that route, and track conditions are implied.

Here are the big 5, and these are simplfied definitions:
Clear - Proceed at track speed.
Approach - Proceed, prepared to stop at next signal, not exceeding 30 mph
Stop Signal - Stop & Stay
Stop & Proceed (Stop signal accompanied by a permissive marker) - After stopping at signal, proceed, not exceeding restricted speed*.
Restricting - Proceed at restricted speed*.

*Restricted speed: A speed which will allow for stopping with-in one-half the range of vision, short of a stop signal, train, obstruction, derail, or misaligned switch, not exceeding 15 mph.

Nick

Take a Ride on the Reading with the: Reading Company Technical & Historical Society http://www.readingrailroad.org/

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Posted by Anonymous on Thursday, March 23, 2006 10:10 PM
Each major European country had its own ideas about both signal design and train working rules... and, AS FAR AS I CAN TELL. so did each of the largest American Railroads. Simple example... Chicago North Western was the only one (that I know of) to run on the (correct) left side. All the others got it wrong like most of the European Railways... some started out left handed and change to conform. (Don't know which side Japan runs on... hope they know).
Do the ex CNW lines now in UP still run left handed?
Can anyone explain "American" signalling to us "foriegners" please?
What does "Approach" mean? Is it the same on all major roads?
A good web site / link would be helpful.

Thanks for the thread and answers :-)
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Posted by cefinkjr on Thursday, March 23, 2006 9:33 PM
Nick has it right. Amber position light signals fairly scream PENNSYLVANIA. They also say Norfolk & Western though. The story here is that most of N&W's stock at the time was owned by PRR and the P Company had a lot of influence over N&W decisions. Several senior PRR officials "migrated" to the N&W back then and that helped. Strangely enough, this influence did not extend to the Mechanical Department and Belpaire fireboxes never appeared on N&W power (at least, not in great numbers if any).

All of that said, there were a few PRR lines with other forms of signals. I don't know where these were but assume they were on lines acquired by PRR with signals in place and the signals were never changed. I think these existed because pre-Penn Central PRR rule books described them. On the other hand, they might have only been on trackage used under trackage rights agreements. I do know that B&O style COLOR position light signals were described in NYC and PC rule books because of trackage rights.

Chuck

Chuck
Allen, TX

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Posted by nbrodar on Thursday, March 23, 2006 11:52 AM
About 1910 the Pennsy switched to Position Light Signals, that used rows of three amber lamps to mimick the positions of a semaphore arm.
Three verical lights: Clear
Three horizantal lights: Stop
Three light at a 45 degree sloping up left to right: Approach.

As an interesting note, many of the Home interlocking signals, used two horizantal red lamps instead of three amber ones to indicate stop.

They were and still are a PRR trademark.

Nick

Take a Ride on the Reading with the: Reading Company Technical & Historical Society http://www.readingrailroad.org/

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Posted by wjstix on Thursday, March 23, 2006 11:29 AM
Well the Pennsy used kinda unusual color-light signals, though like all railroads they did use semaphores. For the US we don't use the 'epoch' or 'era' like European modellers so I'm not sure what your time frame is, but I would suggest checking with maybe the Pennsylvania RR historical society etc.

I think most Pennsy modellers use the Pennsy style color-light signals because they are so unique to the Pennsylvania RR.
Stix
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Colour or semaphoresignals?
Posted by Anonymous on Thursday, March 23, 2006 11:21 AM
I shall building up Pennsy style on my layout and it shall been between epoc 2-4.So,what style of signals shall i using by installed up?I like by using coloursignals like green and red.Or what do you suggest to me?

agge [?]

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