On my current layout, which I built for personal enjoyment and not intended to be prototypical, I installed signals in the appropriate locations. However, I installed them so I could easily see them and their red/green lights from where I would most often be standing to operate the layout. So, the signals are not necessarily facing the direction of the train crew in all cases.
My question is this. What is the proper protocol for the placement of signals? When are they supposed to be seen from either direction? Are model signals made to be seen from both directions? Where are signals supposed to be placed and what type of signal is most appropriate in each instance?
I am not even sure of the right questions to be asked here, so don’t hesitate to comment on what I need to know for my next layout which will be more prototypical if I can help it.
I’m anxious to read the replies to your questions! Years ago I picked up a small Kalmbach book called “Signals” (I believe) and it was a major help in understanding what they are all about.
I believe (NOT positive) that signals are placed to give the train crews the best view. Most RRs run contrary to vehicle traffic on multi lane mains, so typically the signals would be on the left side - but not always. Also, as I recall from my youth, the C&NW is one of the majors that ran the same as vehicle traffic, and of course their may be others that do that too.
From a modeling perspective, especially if one has operating signals, I would want them placed so I could see them. Those that need to be pointed away from the operator could be dummies. After all, operating signals can cost some major bucks for even a relatively small layout.
I’m not sure I agree with this. I believe that generally most railroads are right hand running. And the signals would be mounted facing the train on the right side, as this is the engineer’s side. If the main is single track, then the signal for the opposite direction would be on the left side of the track and be facing the opposite direction.
On a multiple track main there would probably be an overhead signal bridge of some type. In this case the signal would face the on-coming train, and would be offset to the right. The opposing signal would be mounted on the other side of the signal bridge, and be offset to the other side where it could be seen by the engineer.
To completely answer your questions would require a couple books worth of answers.
Signals are obviously placed facing the direction of movement they govern. Where they are placed depends on what type of signal system is involved (ABS, CTC, Interlocking) and what they govern. Whether they display signals in both directions on the same mast depend on what type of signal system is involved (ABS, CTC, Interlocking) and what they govern.
Then there is the issue of what you are doing with regard to the model system, since many model signal systems aren’t set up to operate like a prototype system. Many are just switch indicators, most don’t have full intermediate and approach signals, many are set up for just 2 color (R/G) as opposed to prototype signals with 4 colors (red-yellow-green-lunar) and flashing aspects.
It might help narrow down and focus the answers if you told us what you were ging to use the signals to do, what prototype railroad or area you are modeling and what era.
On one of the lines I railfan regularly, older signals laid out like maxman mentions are being replaced with single masts that have both directions on them:
So era might be another factor to consider.
Here’s a website I’ve found useful for explaining the basics of how signals are used:
As far as the modeling them goes, I have only operated on one layout that had a signalling system. It seemed that the viewing angle was such that I could always see the aspects even though I was not sitting in the HO scale cab. I did not look too close, but I think either the bulbs were sticking out farther than the hoods, or the hoods didn’t stick out as far.
Ooops, my coffee hadn’t kicked in yet and I got it backwards. I actually caught it myself as I was reading the postings, and then saw your note. Ha, I’m a pretty good typist and too many times I do not go back and check what I wrote. I need to work on that!
Moobilman, for lack of a better label you may have been afflicted with what I call “Mark’s syndrome.” When keyboarding, I’m often writing the opposite of what I’m thinking, like up/down, left/right, west/east, agree/disagree, etc. Proofreading closely often doesn’t work, but immediately after posting the errors are glaring. Seems like I’m always editing my initial posts within minutes.
Is there a medical title/description for this affliction other than “mentally defective.”
Hmmm. Not sure what is going on here. Those signals look like they’re facing 90 degrees from each other. Is one of the heads mounted temporarily?
Regarding visibility on the model…the signals on my friends railroad are generally close enough to the aisle that the “engineer” can see them as he walks with the train. There are certain locations, however, where the signal head is turned slightly toward the aisle so that the 1:1 scale engineer can see them. The HO engineers would probably have a visibility issue, but so far none of them have complained. Or maybe they are complaining and we can’t hear their 1/87.1 scale voices.
Sorry - when I took that picture, the signal had been newly installed but not yet activated, which is why the heads are turned aside. When it was activated, the heads were aligned with the track as normal.
That might be true. Most railroads run with the small hood forward, so I’d guess that there would be adequate visibility for the engineer to see the signal no matter which side of the rails it might be mounted. I would assume that as long as the engineers knew the rules for that section of railroad there would not be a problem, at least on a single track line. Not sure what they would do on multiple track.
I don’t think you would find signals mounted that way when there was a boiler or long hood at the front of the engine.
Prototype signal heads have mounting adjustments so the light can be aligned for best sighting. If the track is curved, spreadlight or deflecting lenses may be required to make a wider beam. (Page 61 of Introduction to North American Railway Signaling by the Institution of Railway Signal Engineers)
An old timer, who is a retired railroad employee ,explained it to me this way "generally speaking most signals were located on the engineers side or what you people would call the right side not only for the fact that the engineer is the guy running the train so of course he should have clear view of the signal and also for the simple fact of logistics for the equipment needed to support the signal. To quote him “They don’t work on air” so why run cables under the tracks and in the event that you have some sort of problem where the cables were effected you would now need to take up the tracks for repairs and halt revenue service again to quote him, “yeah like that would put a smile on the face of some mucky muck up in the front office” He ended his little railroading lesson by saying well there’s always an exception to the rule and walked away with out explaining it…lol
Any place a single mast is used for signals in both directions (such as the picture of the signals shown above), one signal will be on the “wrong side”, the fireman’s side for half the trains.
I don’t believe the OP has provided any additional information on what he intends to use the signal system for or how complicated he wants to make it. Without some input on that it will be difficult to help him.
This line (CN’s Holly Subdivision) is double tracked between Pontiac and Detroit. For the newly installed signals, each main track has its own single mast, mounted on the “outside” of the track. Each mast has two heads pointing in opposite directions, similar to the above.
But that’s just this CN sub - other prototypes may be different. The OP will want to do some additional research when his focus has been narrowed beyond gathering background info.
Yes, Dave, I understand that and it seems pretty obvious to me that that would be the case. But era was mentioned above. So my question would be in the era of steam engines and 1st generation diesels operated long hood forward, where the engineer’s visibility is restricted, would they have put two signals for opposing directions on the same mast, assuming a single track line? Or is this a “modern” day practice?
My apologies for starting this thread and then disappearing. My kids and grandkids are in town, and we have been running around visiting, and I have not been able to manage this thread until now.
dehusman indicated earlier in this thread that it might help narrow down and focus the answers if I told us what I was going to use the signals to do, what prototype railroad or area I am modeling and what era.
Good point.
Currenty, I have a large L-shaped layout with a double mainline, measuring 42’x22’. It is freelance and not based upon a prototype. I operate in DCC and the main control panel is at the point where the L forms two legs. All of my signals face this point, so that I can see them and their lights. But that means that an engineer coming toward me cannot necessarily see the lights on the signal. I have two types of operating signals, single and double searchlights and dwarf signals, green over red. I also have a few non-operating signal bridges.
I use the searchlights for all turnouts on the double mainline - - green for straight through and red for divergent. A single turnout has a single searchlight signal. A crossover has a double searchlight signal. Why do I do this? Quite honestly, when I set these signals up 7 years ago, I thought it looked cool and it helped to visually show me how the turnouts were set. I gave little regard to prototypical operation.
Up until the last decade or so, signals were required by regulation to be above and to the right of the track that they were controlling. Now they can be on either side of the track, so you do sometimes see a signal mast with two heads pointing in opposite directions. You would never have seen that before maybe the 1990’s.
As for no. 3…
The answer above partially answers it, because you had to have the signal heads above and to the right of the track. If you had say a four track mainline, you often wouldn’t have clearance between the tracks to install four separate signal masts between the tracks. Signal bridges allowed each signal to be above and to the right of the track as required. Signals could be placed on both sides of the signal bridge depending on the trackwork it was controlling.
This has changed a little in recent years, but traditionally a single head signal was a block signal, indicating whether the track blocks beyond was clear. Red means the block you’re coming up to is occupied and you normally have to stop; yellow means the block is clear but the next block is occupied; green means the next two blocks are clear.
A double or triple head mast usually is an interlocking. This means that there is either a crossover from one mainline track to another (as you’d normally see approaching a busy station), a branchline branching off, or two rail lines crossing at grade. If you came up to a turnout where a branchline split from the mainline, you would see green over red if you were going on the mainline, red over green if you were going on the branch, and red over red if the turnout was aligned for a line that had the next block occupied.
The other two lines above, converging together to become one line, are often signalled in models by just using a single red or green signal head. However in the prototype often a “dummy” red light is added, so it can show green over red for clear or red over red for stop. That’s b
They should be viewed by a train approaching them. If they don’t point down the tracks then they are “out of service”.
If you are just putting signals on one side then it really doesn’t matter.
The same function as every other signal. To convey information regarding route, speed, authority and how trains approach the next signal.
If all you are doing is indicating switch position, then I wouldn’t get too worked up on being “prototypical” since whatever you do will not be strictly prototype.
A couple of questions regarding searchlight signals.
On the prototype, where and when were single searchlight signals used versus double searchlight signals?
In my circumstances, if I am merely using searchlight signals to indicate the position of the turnout, would I always use single searchlights? Or, how offensive would it be if I used double searchlights for crossovers and single searchlights for simple turnouts?
