Good morning/afternoon/evening folks, wherever you may be...
I'm rapidly heading towards finishing the landscaping of my layout, and always knew that I would wait until then...and until more structures were built...before I messed with...SIGNALS!
I know they are key. I think that working signals add a huge element to a layout. Now I am starting to think about them, especially since I guess I'll have to drill new holes and make new space underneath for the signal electronics. However, I know not a drip about signals, how they work, why which type were put in different situations, double track, single track, yard signals...target signals, low signals...working MR signals with electronic track sensors...I'm completely lost when it comes to Signals. I got the book "Lineside and Trackside Detailing" hoping that it would teach me the ABCs of Signals and why and how they are deployed, but it helped me basically not a whit. Not looking to scratch build the buggers, just understand how I should and can use them.
Can anyone tell me a bit about when and where I should use different signal types (I model Y2K - year 2000, on ex-N&W/SOU lines - and I understand each old time RR had their own unique signal types), or probably more practically, refer me to an affordable, accessible resource that would clue me in on the mysteries of track signals?
Also, what are the best working MR signals to use - Atlas, Tomar, NJ - and what is needed to optimize these signals in DCC? Any opinions/advice?
Many thanks!
Shawnee
I'm glad you started this thread, shawnee, because I'm in the same boat. I've spent 4 decades in this hobby but am a total newbie when it comes to signals. Like you, I intend to retrofit mine as a finished detailing project. Any information anyone can provide regarding either prototype or MR signaling will be appreciated.
Basically there are two general conficgurations of signals, ABS (automatic block signals) and CTC (centralized train control).
In ABS (or APB), single track, the signals only convey track occupancy, switch position information. They do not convey main track authority (Form D, track warrants, DTC, yard limits, etc) would grant the main track authority. the dispatcher does not control or line any switches or signals.
In CTC the signals at convey the same track occupancy information, but signals and switches at certain locations, usually called control points (CP), are controlled by the dispatcher and the signals grant authority to proceed on the main track.
Depending on whether its ABS or CTC there may be differences in signal placement and use slightly different styles of signals.
MR had a series of articles several years ago on building a signal system and it was on a NW or SOU layout. If you search the internet there are severa very good sites out there on signaling. And you will want to get a rule book for your RR for your era.
Dave H. Painted side goes up. My website : wnbranch.com
Dave, that's great info. I take it then that ABS signals are less expensive than CTC signals in the prototype. Are both equally prevalent in the prototype, especially say year 2000 or so...? I have two lines that i'm modelling, one a NS or CSX branch line (depends upon which locos/cars I'm running) and one a steep mountain pass branch line that NS spun off (formerly NW or SOU) to a shortline, called the Alleghany and Kanawha. Wondering if it is more likely that a shortline would have those ABS signals, and whether a branch line of a class one would still have ABS signals.
Those ABS signals seem easier and less complicated to deal with, just track occupancy, seems like it's more to my speed, so to speak. I'm not constructing elaborate control systems or such...not at my skill level to have the signals signal track authority I would suppose. I guess the track occupancy sensors are the ones that Atlas sells.
Are there any specific on signal targets and equipment that would be particular to a siding, for instance, or an entrance to a small yard? Or a junction? Do yards have signals for each holding track? What's the requirement for signals in a small shortline yard?
Lotsa question I know... Like I said, I'm clueless about signals. I figured it's time for me to start thinking about them. I'm all single track line, but several sidings, a small yard and a couple of track junctions. Thanks for giving me a start...
If you are really interested in modern prototype railroad signalling practices, examine the book Introduction to North American Railway Signaling by the Institution of Railway Signal Engineers and published by Simmons-Boardman Books in 2008.
Mark
shawnee What's the requirement for signals in a small shortline yard?
What's the requirement for signals in a small shortline yard?
Per the Institution of Railway Signal Engineers in a 2008 publication "Lightly used branch lines and many short line railroads do not operate with these methods. This is called dark territory, where there are no signals to 'light the way.' About 40 percent of North American railroad trackage has no signaling." By "trackage" I don't know whether the institutions includes only main and passing tracks or if it also includes yard, spur, service, track, etc. also. I suspect it is the former.
I spent a great deal of time a couple of months ago looking into the various signals available and the signaling systems. Like you, I wasn't looking for a full blown signaling system...just signals to show track occupancy. What i decided to go with is the Atlas signals and control boards and the NCE BD-20's for detection. If you are looking for dwarf signals for turnout indication I have always been satisfied with the ones available from NJ International.
Dave
'there's something happening here, what it is ain't exactly clear' Modeling the Hard Knox Valley Railroad in HO scale http://photos.hardknoxvalley.com/
Mark, that's interesting. So dark territory means no signals....at all! One question - forgive the ignorance here - in dark territory, on those branch and shortline tracks, how do trains know if there's another train down the track...i mean, isn't that an invite for a "cornfield meet"?
I would assume in a small yard there need not be signals since it's, well, a small yard.
Does anyone know if NS or CSX have dark territory on their lines - or are they all CTC now? In ABS, does that mean that signal towers are still in use with those, since someone needs to control the switch - i know that certainly when/with CTC towers are obsoleted. But I seem to recall that CSX still might have a tower or two in operation on their lines.
On the book you mentioned, well y'know seen that, but it's expensive and I'm trying to avoid a dense textbook, got enuf technical reading in my life already, Just looking for enough info to set up some cool operating environment for my MR... Maybe I can dig up the articles in MR magazine that were discussed, is there an online way to find out from Kalmbach about content of way long gone issues? I just need enough to feed my ignorance on the subject and do something light and fun with signals on my layout. Suprised there isn't an MR book that goes into the subject as they do, say, for yards, industries along the track or freight cars.
I think some ABS signals sound like they would be cool however, just track occupancy stuff that lends to a neat effect on my layout. Maybe my other shortline can be "dark territory". Hmmm... Food for thought.
shawnee Mark, that's interesting. So dark territory means no signals....at all! One question - forgive the ignorance here - in dark territory, on those branch and shortline tracks, how do trains know if there's another train down the track...i mean, isn't that an invite for a "cornfield meet"? I think some ABS signals sound like they would be cool however, just track occupancy stuff that lends to a neat effect on my layout. Maybe my other shortline can be "dark territory". Hmmm... Food for thought.
In dark territory, the route could be declared to be within "yard limits" and use the rule that trains can't move faster than can be stopped in half the visible distance. Usually, trains operated under instruction of a dispatcher and perhaps a timetable.
ABS is simpler because it is essentially a train detection system, however, it does not in itself give authority to the train. Under CTC, signals don't change except under the authority of the dispatcher, thus they show "red" except when the dispatcher changes it to give authority of the train to move. With CTC, you need a human dispatcher to operate signals on the layout.
i'm installing a signal system on my n scale layout. it is also single track with a yard and industry sidings. presently i have one working signal which i have placed at a switch entering the yard. it is an atlas g type double head signal that shows green over green for a mainline route and yellow over yellow for a yard move. i am using several dallee current detectors around the layout to operate the signal and it goes from red to yellow to green depending how far the train goes from the signal. the atlas signals are very nice but i am using relays and circuits of my own design and not the atlas circuit boards. the cost is about the same but i can get the effects that i want such as directional control and route indication. i have a short video of it but i don't know how to post it here. i was a signal maintainer and i'm using circuits that were used on the signal systems i worked on.
Dark territory, you usually have some form of schedule or knowledge where your trains are, if running multple trains, you will need a dispatcher. I have done dispatching on the club I was on , we didnt have signals, but we had telephones around, operation was done by train order. ABS is done this way also, the South Shore has been this way for years, they recently have gotten CTC installed.
NS (N&W merged in) uses pennsyvania style signals for the N&W sections of the line, I don't know what the Southern had. The signals doesnt use colors but instead lights arranged like the semaphore signal used. 3 vertical lights, proceed, 3 horizontal lights, stop, 3 angled lights, permissive.
There are many resources for signal controlling, perhaps check the walthers catalogue, the electronic projects books 1 and 2 has info for signals.
Bruce Chubb had a series of artcles in MR for computers and signaling and he has a good detector design.
http://www.jlcenterprises.net/index.htm
These guys sell the detector card, that have a signal card, for a target signal, but actually making a controller for a PRR signal isnt really tough.
shawnee Mark, that's interesting. So dark territory means no signals....at all! One question - forgive the ignorance here - in dark territory, on those branch and shortline tracks, how do trains know if there's another train down the track...i mean, isn't that an invite for a "cornfield meet"?
A line with just ABS signals, and one that is "dark" would be operated the same way. Since ABS conveys no authority, just occupany information, you still need another system for movement authority, whether that be Timetable & Train Orders, Track Warrant Control (TWC), Occupancy Clearance System (OCS) (similar in concept and execution to track warrants - used in Canada instead of TWC), or "other."
At sidings, the train crews throw their own switches manually. Meets are controlled by the dispatcher.
Chris van der Heide
My Algoma Central Railway Modeling Blog
Note that in general, signals convey three pieces of information:
1. Whether or not the following block is occupied
2. What the next signal indicates.
3. Either the route to take, or the speed to pass the signal/switches. Some roads used signals that indicated what route would be taken through switches or interlockings, other roads use speed signalling. With speed indications you can pretty much infer the route though, since straight through would give you "Clear" while diverging route could be "Slow [or medium or limited, depending on the allowable speed through the switch] to clear"
For an example, consider a train meeting another at a siding. The other train is already holding the main between the siding switches. Our train arrives at the siding switch, and is greeted with a stop signal (Red over red). We stop and the conductor gets out and throws the switch, and we get a "slow approach" (Red over yellow) into the siding. At the other end of the siding we get a dwarf signal indicating stop. Throw the switch and we get "Slow to clear" (Green on the dwarf; Red over Green if it were a full mast signal) leaving the siding, if the next two blocks are clear. Meanwhile at the other end of the siding, the conductor on the other train throws the switch back to its normal position. Once the switch is lined normal, his Stop (Red) signal changed to Clear (Green), and assuming he has authority from the dispatcher to do so, he can take off.
Of course there are almost limitless scenarios - the above is just the simplest, of a siding with at least two blocks between it and the next siding, interlocking or control point.
shawnee Are there any specific on signal targets and equipment that would be particular to a siding, for instance, or an entrance to a small yard? Or a junction? Do yards have signals for each holding track? What's the requirement for signals in a small shortline yard?
Often an ABS siding would have a pair of signals, one facing in each direction, at each end of the siding, on the single track portion past the points. No signals on the siding.
There would not necessarily be any signals at the entrance to a yard and no signals in a yard. Unless you were modeling a major hump yard, there would be no signals in a major yard either.
Depending on what you call a "junction", a crossing at grade could be either a manual interlocking or an automatic interlocking. Manual would have either the dispatcher or a control operator line the signals and or switches. An automatic interlocking is set up so that the first train to step on the approach to the crossing gets the signal.
Not sure what you mean by a holding track. At an ABS siding there could only be signals on the single track portion and none for the siding itself. You wouldn't need any since the signals don't tell you wether or not to head in, your orders/warrants/DTC blocks do.
ABS, CTC and dark territory are all very common. Double track current of traffic, which was ABS on double track, was very popular in the 1920's and 1930's but it is being replaced with CTC. Some roads have CTC with no wayside signals, only cab signals.
cv_acr For an example, consider a train meeting another at a siding. The other train is already holding the main between the siding switches. Our train arrives at the siding switch, and is greeted with a stop signal (Red over red). We stop and the conductor gets out and throws the switch, and we get a "slow approach" (Red over yellow) into the siding. At the other end of the siding we get a dwarf signal indicating stop. Throw the switch and we get "Slow to clear" (Green on the dwarf; Red over Green if it were a full mast signal) leaving the siding, if the next two blocks are clear. Meanwhile at the other end of the siding, the conductor on the other train throws the switch back to its normal position. Once the switch is lined normal, his Stop (Red) signal changed to Clear (Green), and assuming he has authority from the dispatcher to do so, he can take off.
An alternative is we are going to meet another train and have to clear the main track. The other train is already at the station on the main. We get an approach to our end of the siding and a stop at the siding. Since we are going to head in for the meet, the rules allow us to stop and then pass the signal displaying stop to clear in the siding. At the other other end the switch is a spring switch. We stop. The signal just beyond the switch is clear. But since we have to meet another train/don't have authority past that station, we can't depart. We contact the dispatcher and get authority beyond our current station. The signal beyond the switch is approach, so we depart and enter the main track, not exceeding 30 mph after our train is on the main, prepared to stop at the next signal.
markpierce ABS is simpler because it is essentially a train detection system, however, it does not in itself give authority to the train. Under CTC, signals don't change except under the authority of the dispatcher, thus they show "red" except when the dispatcher changes it to give authority of the train to move. With CTC, you need a human dispatcher to operate signals on the layout.
Sorta. In CTC the there is a full underlying ABS system. So the dispatcher doesn't determine what signal indication is given to the train (except for "stop"). The dispatcher lines the route and clears the signal and the signal system (ABS) determines what signal is displayed. The train gets the best possible indication for the situation Depending on what the conditions are that could be clear or that could be stop or it could be anything in between.
Mark is exactly correct that if you want CTC you will have to have a dispatcher to line the routes and signals.
You need this:
http://cgi.ebay.com/All-About-Signals-1977-RAILROAD-DIAGRAMS-DETAILS_W0QQitemZ120385252643QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item120385252643&_trksid=p3286.c0.m14&_trkparms=72%3A1729%7C66%3A2%7C65%3A12%7C39%3A1%7C240%3A1318%7C301%3A1%7C293%3A1%7C294%3A50
http://cgi.ebay.com/All-About-Signals-John-Armstrong_W0QQitemZ250380071724QQcmdZViewItemQQptZModel_RR_Trains?_trksid=p3286.m20.l1116
Just be glad you don't have to press "2" for English.
http://www.youtube.com/watch?v=zQ_ALEdDUB8
http://www.youtube.com/watch?v=6hqFS1GZL4s
http://s73.photobucket.com/user/steemtrayn/media/MovingcoalontheDCM.mp4.html?sort=3&o=27
Carsten Lundsten has a great website that describes the different variations of North American signaling practices:
http://www.lundsten.dk/us_signaling/index.html
There are lots of step-by-step examples with graphics that show how the different signal systems (ABS, APB, CTC, etc) perform in certain scenarios. Also a good discussion about track warrant control (TWC) and Direct Traffic Control (DTC). There is a lot of information covered, but at a pretty high level so you are not reading big blocks of text over and over try to digest what is being said. Jamie
dehusmanMark is exactly correct that if you want CTC you will have to have a dispatcher to line the routes and signals.
Or a computer.
CLICK HERE FOR THE CSX DIXIE LINE BLOG
dehusman Often an ABS siding would have a pair of signals, one facing in each direction, at each end of the siding, on the single track portion past the points.
Often an ABS siding would have a pair of signals, one facing in each direction, at each end of the siding, on the single track portion past the points.
Modelers' frequent misuse of the word "siding" causes a lot of confusion. The use above is correct for North America where "siding" means a track dedicated to allowing two trains on the same track to pass. (The British term for "siding" is "loop.") This is usually in the form of two turnouts facing each other to create a second track, the siding, paralleling the main track so a train can get off the main so another train can pass, and once that train passes, the train on the siding can proceed onto the main track. It is common for track arrangements to superficially look like sidings while in reality they are only double-ended spur tracks, yard tracks, etc.
In North America, a side track or spur is a track that is not "main" or "siding," for example a track serving an industry or for storing cars. Unfortunately, modelers of North American railroads misuse "siding" when they are referring to side tracks and spurs. Part of the confusion is probably due to the British using the word "siding" to mean a side track or spur.
Raised on the Erie Lackawanna Mainline- Supt. of the Black River Transfer & Terminal R.R.
shawneeGood morning/afternoon/evening folks, wherever you may be... I'm rapidly heading towards finishing the landscaping of my layout, and always knew that I would wait until then...and until more structures were built...before I messed with...SIGNALS! Also, what are the best working MR signals to use - Atlas, Tomar, NJ - and what is needed to optimize these signals in DCC? Any opinions/advice? Many thanks! Shawnee
To make a working signal system, you need some form of block detection, then a way to control the signals. There is a couple of ways to implement a signal system for a model railroad. - One is to do it piece-meal, buying parts here and there and assembling as you go, and hope that manufacturer does not discontinue the parts you have chosen to use. The electronics would be stand alone circuit boards with built in logic.- The other way is to computerize them. You still need block detection. The best thing going now is the SE8C Signal Decoder board and the BDL-168 Detection board, both by Digitrax. There are some problems if you want to go this way. Cost. The SE8C is $125.00 but will control 32 signal heads, plus some other parts are needed such as the cables and signal interface kits. The BDL-168 costs $150.00 and will detect 16 blocks. On top of that you will need a computer program. JMRI Panel Pro is free, but the learning curve is steep. (Takes a while to learn.) If you are an adult with a job, this is the way to go in my opinion. If you are a teenager, this is not for you.If you don't use Digitrax DCC, you can still use the Digitrax boards mentioned above, but you will have to do a little more work and install a LocoNet. I have an NCE Power Pro system and I have done it. Note: "You won't be able to use a starter or entry level DCC system." For more information, go to this site:
http://mysite.verizon.net/vzescsbb/HO_MRR/C&A%20Main%20Page.html
This is a small site about my HO MRR. The link you want for adapting Digitrax boards to other DCC systems is down at the bottom.
Hope this helps.
Elmer.
The above is my opinion, from an active and experienced Model Railroader in N scale and HO since 1961.
(Modeling Freelance, Eastern US, HO scale, in 1962, with NCE DCC for locomotive control and a stand alone LocoNet for block detection and signals.) http://waynes-trains.com/ at home, and N scale at the Club.
A lot to swallow there, Shawnee. Indulge. Simply, signals are cool. They add distinction to a layout.
How far you want to go with signals is up to you.
A basic signal circuit system... detectors and signal drivers is all you need, no computers.
Building your own signal circuit is not so tough, just a little down dirty wiring of components and a little planning. One signal would have 2 signal inputs and one signal output , one connection throws it to red, next connection throws it yellow, the output shoots a yellow send to the next signal when the immediate signal is red. So each signal would have 3 connections other than its power connections.
The the detector shoots out the detection connection which goes to the immediate red connections of that blocks signals.
For me I have debated and debated how to deal with signals and my best desire if the signaling has to get complicated with a myriad of tracks going on is you have to use a computer or your wiring just gets fanatic. It means some down and dirty computer programming unless theres a suitable signal planning software out there.
DCC may have answers to all this but I haven't explored that deeply yet, but simple ABS stuff nets the coolness and gets ya going. Experiment, get one detector and one signal going and grow it from there.
I may be back and find more stuff for ya.