Prototypical railway signals?

[Jacktal]

I am looking for infos on the different light boards that railways use to let the train engineer know in advance which way turnouts are thrown,what are the lights positioning,colors,sequencing,distances from track and TO,etc.

I want to install such warning devices on my layout so that I don't have to walk to every TO to check their positioning and avoid the constant hassle of derailing and/or shorts caused by locos entering wrongly thrown TO's.I can handle the electrical but don't know how these work in the real world.I'd like these to look like the real thing also.Thanks.

[RDG-LNE]

Railroad signalling is a very difficult subject to explain in just one brief forum posting. There are several groups dedicated to the history and study of railroad signalling over on Yahoo. I've been studying signals for years and have only scratched the surface. What prototype do you follow and what kind of interlockings did it have at the time you model?

Drew

[Jacktal]

I haven't limited myself to a specific era for my roster.Depending on my humor,I may run my Challenger or a consist of SD90's,although never at the same time.So I don't intend my layout to be a rigid time frame.However,I've settled for western U.S. and canadian railways (UP,CP,SOO) and a few Santa Fe units.

So for me,a functional system is the goal,even if looking somewhat out of date for purists.And for the time being,I would limit this lighting system to TO operations,as I very well know that railway signalling is far more complex.I'll keep this for future upgrades.Thanks.

[dehusman]

Real signals do more and convey more than just the position of the signals, they also convey track occupancy.

Are your turnouts manual or powered? If manual, what type of mechanism do you use to throw them? Do you have some sort of electrical switch connected to every TO that can control a signal to tell you which way a signal is thrown?

Dave H.

[Jacktal]

I'm actually planning my own layout with no restricted time frame as I own quite different rolling stocks that I all like and run as my mood calls.Based on my experience at the club,where constant shorts happen (Digitrax DCC) because locos enter wrongly twrown TO's,I want to design a system that will allow me to know how TO's are thrown without actually going to them to check all the time.

At a later time,I will have a control panel that will duplicate these signals,but since I like the walkaround way of operating,I don't want to be stuck at a single place in front of the layout.Each TO will have its switch nearby along the layout side so that I can throw them at will as I follow my train(s).

I will use Peco Electrofrog TO's (N scale) with Peco PL-10 solenoids coupled in parallel with Atlas Snap Relay's that will enable me to both power the frogs and actuate a lighting system.I plan on using LED's for this,to try to keep the signal system as close to scale as possible but don't mind a slight deviation as it may not be possible to do so.However,I'd like to have something that will at least closely ressemble the real thing.Thanks for any infos.

[dehusman]

First off, engines running into switches lined the wrong way isn't a signaling problem. The root cause there is sloppy and careless operators.

Basic concept : Line every switch for the main track or normal route. Line it for the diverging route ONLY when using it. When you are done with it LINE IT BACK FOR THE MAIN.

What it sounds like you want is not a signal system but switch indicator lights along the fascia that tell you which way the switches are lined.

Dave H.

[Jacktal]

I understand what you mean and it surely sounds as the right procedure to follow.Unfortunately,at the club I belong to,the guys throw the TO's for their own intended purposes and just leave them as is after,meaning that when you operate you always have to run ahead of your train to check the TO's.This is complicated when multiple TO's are ahead and what makes things worse is that N scale is small so that TO positions aren't easy to see specially from a few feet away.

As you stated,"switch indicator lights" is a more appropriate term for what I want and these would be nice on the fascia next to the actuating switch and I will install such on my layout.However,I will also have a duplicate next to the TO itself and try to disguise them as prototypical railway signals so that I can concentrate on my train(s) and the track ahead,therefore going to the fascia only when a "no go" signal is on.

As far as the club's layout is concerned,I guess I'll just live with the guy's ways.....

[John Busby]

Hi jacktal
I take it you are talking about a point indicator a device that tells the driver which way the points are set these are quite common in yards and on branch lines.
On the main line they are usualy tied in to the signaling system so it the points are set for the diverging route the only signal that can clear is the signal for that route and it will only clear if the line is clear as far as the next signal.
The simplest form of point indicator is pair of discs or disc and bar that rotates through 90 degrees one disc will be for arguments sake red if the driver can see that disc
The points are set for the diverging route if green for the main line often refered to as normal & reverse in the signaling world however you also have catch points designed to throw the train off the track if it tries to get on the main line these have a different shaped target so there is no confusion. between the two.
It should be noted that different railways use different colours for the disks which may have an additional meaning to them on top of which way the points are set
Another style of point indicator consists of three 8" Dia lunar white lights in a triange shaped back ground.
When the lights illuminated are one above the other the points are set for the straight when the lights are on an angle the points are set for the diverging route and This type can be set up for left hand or right hand points.
I would sugest looking at your railway and designing a signal system to suit bearing in mind it will be impossable to replicate a full signaling system yours and no one elses on the forums will be anything like big enough to replicate a full signaling system.
You could also mean theater indicators which are part of a signal in a large station
which illuminate as a letter and indicate where the train is going for instance "M"
would mean the train is going to platform 7 which is where the Midland train goes
to it tells you the route that is set but you still must obey the signal underneath it
red stop yellow prepare to stop ect.
Railway signaling is a subject all on its own and can get quite complex.
But it all boils down to is it safe and if it fails will it fail safe.
Three micro white LEDs should do for the lights with a home made brass targets
two targets and 6 lights per set of points one facing direction one trailing dirsction mounted at such a hight on the same mast so the driver can see them as he aproaches
regards John

[dehusman]

Real simle put an LED or pair of LED's near each switch (where the switch stand would be) and wire it so when the switch is normal the LED is out or green, when it is lined for the diverging route, it will be red.

Dave H.

[Jacktal]

Thank you both Dave and John as you've both been great help.I think I will go for the three lights at angle arrangement (vert=straight and hor=diverging) as I believe it will look reasonably prototypical and will serve the purpose very well without much complexity in design.I don't know which era/area/railway combination it will look most like,but then I don't really care as only purists will be able to tell.I wanted a minimal scale like approach and I believe this will do it fine,at least for me.

All that's left for me to find is what would be a somewhat prototypical placement (I'm doing it again...)for these like straight or diverging side,right or left,and how far ahead of the TO they usually are to be real useful for the operator in real life.Well,I guess it's what makes this hobby so fascinating to me.Thanks again.

[dehusman]

Just remember the "3 light" arrangement is Australian. If you are modeling N America, that system isn't used.

Dave H.

[nbrodar]

I use LEDs on the control panel in addition to trackside signals to show turnout position. While not prototypical this is the signalling convention I use:

From the point end of a turnout:
Green - lined straight
Yellow - lined diverging

From the frog end:
Green - line for movement
Red - lined against movement.

I place the signals at the clearance points of the turnouts, and use triangular G head signal heads, with LEDs.

Nick

[dehusman]

nbrodar:

Are you familiar with the Schuylkill Valley Model RR Club?

Dave H.

[John Busby]

QUOTE: Originally posted by dehusman

Just remember the "3 light" arrangement is Australian. If you are modeling N America, that system isn't used.

Dave H.

Yes we use it but the componants are off the shelf GRS and US&S componants so it must be used somewhere in the US or else where in the world.
they would not just manufacture stuff for a miniscule market like Australia.
each prototype railroad has variations on the so called standard equipment.
As I understand it what was wanted was a high visability but unobtrusive
point indicator that looks believable and you cannot get more unobtrusive than using something that looks like it should be there because thats what a real one does.
It may not be strictly correct but it certanly will not look out of place if the equipment case and point machine casting are correct for the railway being built

Hi Jacktal
Will have a look in my work books I am pretty sure I have a line drawing of the mast and targets some where
If not I will get a photo of one for you the next time I have to work on one.
You will also need a suitable location (equipment) case casting and dummy point (swich) machine casting to complete the details for the scene add a white 4wd
and two signals branch employees and you have a mini scene[:D]
regards John

[marknewton]

QUOTE: Originally posted by John Busby

Yes we use it but the componants are off the shelf GRS and US&S componants so it must be used somewhere in the US or else where in the world. They would not just manufacture stuff for a miniscule market like Australia.

They would and they did. Both manufacturers produced equipment specifically for Australia.

All the best,

Mark.

[marknewton]

QUOTE: Originally posted by dehusman

Just remember the "3 light" arrangement is Australian. If you are modeling N America, that system isn't used.

Are you referring to three-aspect signal heads, or "rabbits-ears" route indicators?

All the best,

Mark.

[nbrodar]

Dave,

Yes, I am familary with the Schuylkill Valley Model RR Club. Although it's been a couple years since I've been there. I'm hoping to get back this November or December.

Nick

[dehusman]

I used to belong there many moons ago. I laid the track and did the first wiring on the branch line. They might still have some of the buildings I built back in college.

Dave H.

[wjstix]

For North America, interlocking signals would be used at a junction where say a secondary line is diverging from the mainline. It would have at least two heads, each capable of at least showing two aspects (red or green). Green over red means you're going on the mainline, red over green means you're taking the seconary routing, and red over red means STOP !! Unlike normal block signals, where red is usually permissive (i.e. you can go thru the red really slowly, easier to keep a long train moving than stop if you don't really have to) with an interlocking you have to stop and wait for it to clear.

BTW in the junction above, if you were coming from the branchline to the mainline, you would probably have a signal with a 'dummy' head, say the top one, which would only show red. That way you would have red over green (proceed) or when the switch is aligned for the mainline, red over red (stop). You only need two indications in that situation. Same for an "x" grade level crossing of two rail lines.

[wjstix]

p.s. Bruce Chubb's book "Operating Your Model Railroad" from Kalmbach has a good chapter on prototype signals and adapting them to the model RR. Not sure if that's still in print but I'm sure you could find it at a flea market or on ebay.

[jimrice4449]

The only place I've seen signals that indicate switch position only (as opposed to speed indications) on the 3 RRs I've worked for is in a yard w/ power switches. If you're going to use the Atlas relays, why not just install LEDs protruding from the fascia (so they'll be visible from a distance) at the location of each switch wire so that a red LED is illuminated when the switch is set for a diverging route and a green when it's set for normal?

[Jacktal]

You know what?...You guys have me absolutely thrilled...and challenged.I love the G/R and R/G idea for discerning which way a TO is thrown when you are coming to it facing the option of going either way.So far so good...and great.But what about when you're coming to the TO the other way?Are there separate panels for each diverging route saying let's say G/R for the main and R/R for the diverging route when the TO is set for the main?And the opposite would say R/G for the diverging route and R/R for the main when there's an in coming train from the diverging track?

In my mind,such warning panels would have to be set at a fair distance from the TO for the train having sufficient stopping distance in case of emergency.So a single panel would be OK for the single end of the TO but what about the converging tracks?I don't think a common panel would suit in every case,would it?What I mean is what happens when a train comes out of a curve onto a straight main track and can't see the TO from a safe distance?

I believe I saw LED's that alternately glow red or green depending on the polarity of the current,which would call for more complex wiring,but I'm up to the challenge.And challenged I am,believe me.Thanks.

[dehusman]

You are mixing apples and oranges here. Your question was about having signals that indicate turnout position.

If you want to add know when trains are approaching, then you need a full fledged signal system with block occupancy detection.

Its the difference wiring a light switch and wiring a house.

Dave H.

[Jacktal]

You're right Dave,I got somewhat carried away indeed.Block detection may eventually be part of my layout,but not for the moment.I'm just trying to be able to tell which way a TO is thrown,and doing this,I thought I might as well try to duplicate how the railways do it,in both directions.

A pair of DEL's that can be seen from both directions would do great,as layout TO's can also be approched from opposite directions too.I was overdoing it as I often do,but that's me......

[John Busby]

QUOTE: Originally posted by marknewton

QUOTE: Originally posted by dehusman

Just remember the "3 light" arrangement is Australian. If you are modeling N America, that system isn't used.

Are you referring to three-aspect signal heads, or "rabbits-ears" route indicators?

All the best,

Mark.

Hi mark
None Of the above[:D]
We are talking specificaly about a point indicator. it has two triangle shaped heads one facing each direction.
They have a triangle pattern of three lunar white lights.
The indications given are
two lights one above the other points are normal
two lights at an angle aprox 45 degrees points reverse
Lights out STOP!!! the points are not right
It should be noted a point indicator is not a signal.
regards John

[dehusman]

If you put an LED AT each switch and wire it to be green when normal and red when reverse, it will substitute for a switchstand and can be seen in either direction.

What I do is use pushrods to control my switches. In is always normal, out is always reverse. You just look down the fascia. If a handle is out, its lined reverse.
Then I paint the pushrods (1/4" dowells) right behind the knob red for main track switches and yellow for other than main track switches. If the knob is out and the rod is red then a main track switch is lined against you.

Zero electronics. Just paint.

Dave H.

[wjstix]

Let's say you're on a single track mainline going north and there's a turnout ahead where the mainline goes straight thru, and a diverging line goes off towards the right (east). As you approach the turnout going north you'd see green over red if you're going straight, red over green if you're taking the diverging route east.

If you were on the same mainline only heading south, you would probably see a two-headed signal, but it would have one of the two a 'dummy' head that could show only red, probably the lower one in this case. So...you could see green over red (meaning you're clear on the mainline) or red over red (stop - the tracks set the other way).

If you were coming from the diverging line to the main, you would probably see a signal with the top light being a dummy red light, so you could see red over green (OK to go onto the mainline) or red over red (stop).

For modelling, you could replace the last two with a signal that just shows either red or green. On the prototype, most red block signals are "permissive" meaning you can go thru them slowly - kind of like a rolling stop at a stop sign in your car. This wouldn't work here so the two lights tells the engineer this is an interlocking signal, not a block signal.

BTW the lights would normally be very close to switch, almost right on top of it.

[nbrodar]

Dave H. makes a good point with putting an bi-polar LED inplace of a switch stand. It's simple although not very prototypical, for a modern layout, now that lighted switchstands are a thing of the past.

Simple single head signals would give a more prototypical look. Few model railroads have signals at all, so the absence of a second head and other block signals will probably go unnoticed.

Also, while it is true most red signals are permissive signals they always marked as such. No number plate, P plate or other marking and it's stop and stay, even if there is only one head.

Nick

[dehusman]

Actually coming south you ould have one head on the main and one head on the "diverging" track" There would be no need for a 2 headed signal since you can't "diverge".

Dave H.

[John Busby]

Hi all
Beware of sweeping statements like most red signals are permisive they most certanly are not.
it all depends on which system is being used there are two systems
permisive block and Absaloute block
and pretty much in both systems it is red stop the line ahead is occupied
I have often seen red point indicators but dont like them because it is red go
rather than the normal red stop.
In signal territory a diverging route generaly means two signal heads or arms
one higher than the other they are read top to bottom left to right
the top one allways being the main line the lower one always the diverging route.
regards John