Help placing signals and things

[AngryMeerkat]

Good evening all, just a few (hopefully) quick questions I hope somebody can help me with ......

 

I'm building a 00 gauge layout, but I know nothing about how the real railways work, but I'm hoping to make my layout reasonably close to the real thing without 'counting rivets'. My layout is set in the 80s but isn't really set in any particular location, and what I'd like to do is place the following items in roughly the right place while adding some scenic interest.

 

Signals

Dummy point motors

Lineside boxes (aws?)

Aws grids on the track

Concrete cable trunking

Cables passing under track (orange protective tubes?)

 

My track plan is as follows, with as many scenic items names as possible

 

Would there be any signals in the depot area? Would the points be motorised or hand operated?

 

Any help would be greatly appreciated.

 

Thanks,

 

Mark

 

Just a quick edit as the picture I have doesn't include everything - the 'bus shelter' is on a mainline station platform, and there will be another platform opposite this on the edge of the board. Neither platform will be full length, and will be modelled as continuing past the scenic break

[phil-b259]

Good evening all, just a few (hopefully) quick questions I hope somebody can help me with ......

 

I'm building a 00 gauge layout, but I know nothing about how the real railways work, but I'm hoping to make my layout reasonably close to the real thing without 'counting rivets'. My layout is set in the 80s but isn't really set in any particular location, and what I'd like to do is place the following items in roughly the right place while adding some scenic interest.

 

Signals

Dummy point motors

Lineside boxes (aws?)

Aws grids on the track

Concrete cable trunking

Cables passing under track (orange protective tubes?)

 

My track plan is as follows, with as many scenic items names as possible

 

Would there be any signals in the depot area? Would the points be motorised or hand operated?

 

 

In most small (like yours) to medium sized depots point control would be done manually with no signals (other than the exits to the mainline) and all movements controled by a shunter. In larger yards and depots (e.g. Clapham Junction, Lovers Walk & Wimbledon) they may well be a small standalone signal box to control movements and in this case most points would be powered but this does not apply to what you have

 

AWS does not use grids in the track - that is TPWS which did not exsist in the timeframe you wish to model. AWS installations themselves are usually located 200 yards before (as a train sees things) the signal to which it applies. Furthermore as they were designed with mechanical distant signals in mind you will not find them at two aspect red/ green signals, but will find them fitted to 3/4 aspects. In appearence they resemble two rectangular lumps of solid metal with a metal ramp at one end to protect the installation from drangling couplings (alternative configurations apply to PSR, Bi-directional or suppressed AWS installations)

 

If you did want to include an AWS installation however, it might be possable to have one fitted at the exit to the depot as a 'test' magnet to ensure the AWS was working correctly.

 

Lineside cabinets (they are not just for AWS despite what model manufacturers say) would be located relativley close to things like Signals and pointwork, with concreate troughing laid to link them together (don't forget the offscene ones). Looking at your diagram, you wont need that many of them, just perhaps a couple at the righthand end and one by the crossover on the left. The main cable route uses a UTX (Under Track crossing) to get from one side of the tracks to another and to get under things like siding connections. Cables from indavidual point machines and signals etc would be surface run across to the nearest troughing route and from there along to the lineside cases. If they have to cross the tracks to do this they will tend to be put in orange ducting suposadly to protect them from tampers and suchlike although I am unsure as to when this practice started.

[Edwin_m]

You need a trap point or a short headshunt siding to make sure that anything that rolls out of the depot when not signalled to do so is derailed before it fouls the main line.

 

A crossover midway down a platform is unusual except in very large stations where different trains might use the two ends. The only ones I can think of are Newark Castle and Romiley. Both of these are traditional layouts controlled mechanically from an adjacent signal box, though Romiley has colour light signals rather than semaphores. The crossovers are only used at low speed and are I think signalled by shunting discs though I'd have to search out some photos to check. What would this crossover be used for?

 

Probably the only visible main signals visible on your layout would be to control moves of trains rightwards out of the depot, the upper platform and probably also the lower platform if trains reverse here and depart over the crossover. These could be semaphore stop signals or colour lights (two-aspect red/green for less busy lines, three aspect for intermediate or four-aspect for very busy lines). There would also be shunting discs or position light ground signals to control the movements over the crossovers, and indeed the depot exit signal might be one of these.

 

I agree with phil about the depot being hand worked, but be aware an AWS test magnet looks a bit different from a normal one. Red/green colour lights do sometimes have AWS if they are part of a wider colour light scheme, but apart from the test magnet none of the AWS magnets are likely to be in your visible area.

[AngryMeerkat]

You need a trap point or a short headshunt siding to make sure that anything that rolls out of the depot when not signalled to do so is derailed before it fouls the main line.

 

A crossover midway down a platform is unusual except in very large stations where different trains might use the two ends. The only ones I can think of are Newark Castle and Romiley. Both of these are traditional layouts controlled mechanically from an adjacent signal box, though Romiley has colour light signals rather than semaphores. The crossovers are only used at low speed and are I think signalled by shunting discs though I'd have to search out some photos to check. What would this crossover be used for?

 

Probably the only visible main signals visible on your layout would be to control moves of trains rightwards out of the depot, the upper platform and probably also the lower platform if trains reverse here and depart over the crossover. These could be semaphore stop signals or colour lights (two-aspect red/green for less busy lines, three aspect for intermediate or four-aspect for very busy lines). There would also be shunting discs or position light ground signals to control the movements over the crossovers, and indeed the depot exit signal might be one of these.

 

I agree with phil about the depot being hand worked, but be aware an AWS test magnet looks a bit different from a normal one. Red/green colour lights do sometimes have AWS if they are part of a wider colour light scheme, but apart from the test magnet none of the AWS magnets are likely to be in your visible area.

 

Thank you for the reply, very in-depth.

 

I did look at putting a trap point or head shunt in, but modelling license came into play here as the track plan just didn't like right with anything added there.

 

The crossover in the station is a similar situation, while this layout will eventually form part of a larger layout I had to do what I can to make it useable at the moment so the station crossover was added just to allow me to move engines around a little more.

 

I think with my expansion plans, I will opt for the 3 aspect signal on both platforms. This will help with the 'small section of larger space' illusion and also fit in with the overall plan. I will also follow the route of position light ground signals for the crossovers, I presume these would face the approach to the crossover on each side? I'm guessing their purpose is to indicate that it is safe to enter the crossover and exit onto the opposite main line?

 

Thanks also to Phil and yourself for the info on the point motors in the depot area, I've seen a few pictures of small depots and the levers were only visible on about 50% of the points so I was unsure what was right.

 

Ref the aws, all I have are the 'grids' that go between the rails. I had a picture in my mind that these would be placed on the approach to a signal, pretty close to it? Or are they placed quite a distance away, and if so could modellers license be applied to allow them to be closer and therefore visible on my layout? At the risk of trying to fit too much in, I like having lots of small scenic details dotted around.

 

Thanks again for the replies, RMWeb is a constant source of education.

 

Mark

[AngryMeerkat]

 

 

In most small (like yours) to medium sized depots point control would be done manually with no signals (other than the exits to the mainline) and all movements controled by a shunter. In larger yards and depots (e.g. Clapham Junction, Lovers Walk & Wimbledon) they may well be a small standalone signal box to control movements and in this case most points would be powered but this does not apply to what you have

 

AWS does not use grids in the track - that is TPWS which did not exsist in the timeframe you wish to model. AWS installations themselves are usually located 200 yards before (as a train sees things) the signal to which it applies. Furthermore as they were designed with mechanical distant signals in mind you will not find them at two aspect red/ green signals, but will find them fitted to 3/4 aspects. In appearence they resemble two rectangular lumps of solid metal with a metal ramp at one end to protect the installation from drangling couplings (alternative configurations apply to PSR, Bi-directional or suppressed AWS installations)

 

If you did want to include an AWS installation however, it might be possable to have one fitted at the exit to the depot as a 'test' magnet to ensure the AWS was working correctly.

 

Lineside cabinets (they are not just for AWS despite what model manufacturers say) would be located relativley close to things like Signals and pointwork, with concreate troughing laid to link them together (don't forget the offscene ones). Looking at your diagram, you wont need that many of them, just perhaps a couple at the righthand end and one by the crossover on the left. The main cable route uses a UTX (Under Track crossing) to get from one side of the tracks to another and to get under things like siding connections. Cables from indavidual point machines and signals etc would be surface run across to the nearest troughing route and from there along to the lineside cases. If they have to cross the tracks to do this they will tend to be put in orange ducting suposadly to protect them from tampers and suchlike although I am unsure as to when this practice started.

 

Apologies for not seeing all this sooner, for some reason my iPad didn't initially show me the part of your post about AWS and TPWS.

 

Some excellent information on the 2 systems, thank you. I was under the impression that AWS and TPWS were different methods of the same thing, and one simply replaced the other, as I remember my dad explaining to me in the late 80s or early 90s what the boxes between the tracks were for. Unfortunately the years have hazed what he told me, so seeing the TPWS grids in the model shop gave me a jolt of nostalgia and a pack was purchased!

 

Thank you again for the great info.

 

Mark

[phil-b259]

Apologies for not seeing all this sooner, for some reason my iPad didn't initially show me the part of your post about AWS and TPWS.

 

Some excellent information on the 2 systems, thank you. I was under the impression that AWS and TPWS were different methods of the same thing, and one simply replaced the other, as I remember my dad explaining to me in the late 80s or early 90s what the boxes between the tracks were for. Unfortunately the years have hazed what he told me, so seeing the TPWS grids in the model shop gave me a jolt of nostalgia and a pack was purchased!

 

Thank you again for the great info.

 

Mark

 

No problem

 

A bit more info on AWS & TPWS is found below and as you now apreciate they are not the same. In essense AWS is there to warn drivers whether they will be approching an aspect which requires them to slow down or not. Providing the driver acknowledges the device there is nothing to stop him from continuing at linespeed with potentally fatal results (e.g. the crash at Purley in 1989). TPWS is there to stop the train passing a red signal and cannot be overiden by the driver unless they come to a complete stand and obay certain instructions. However TPWS is not fitted to every signal and moreover it is not active if the signal is showing a proceed aspect (yellow or green) thus AWS is still a usefull device to have around on the railway.

 

AWS = http://en.wikipedia...._inductor_1.JPG

 

Full article = http://en.wikipedia...._Warning_System

 

TPWS = http://en.wikipedia....e:Tpws_loop.jpg

 

Full article = http://en.wikipedia...._Warning_System

[phil-b259]

More signalling info http://en.wikipedia....n_light_signals

 

How about this

[phil-b259]

Or this one which allows you to have a short train at the platform by the bus shelter and run trains round it. It also allows a train ariving from the right to cross over to the other line ready to return on the correct line (remember trains usually run on the left hand side of double track)

[phil-b259]

Oh yes and with stand alone position lights one white + one red ment stop, two whites at 45 degrees ment go. None of this fancy dual colour LED aspects you see out on the real railway these days.

[peanuts]

re the signal being 200 yds from the signal this is not always the case there are instances where the signal can be right on the points miles platting junction starting signals for instance . in these instances the signal in rear would be track approach ie would not clear untill the train had been on the birth track circuit for a set time usualy 30 seconds this would bring the speed of the train nearly to a stand the signal at the points would be held at red unless the route was set in which case it would clear as the train occupies the birth track circuit

[Edwin_m]

You can also in some circumstances have something called a "swinging overlap" at a facing junction. The signal before the signal protecting the junction can then show a yellow without approach control, if an overrrun distance (the overlap) can be locked and is unoccupied over one of the routes through the junction for enough distance (normally 200 yards beyond the signal protecting the junction). Facing points within the overlap can be changed, providing this allows the overlap to swing onto another route which satisfies the same conditions. In practice it's a whole lot more complicated than this, and pretty horrendous to implement.

[phil-b259]

While I am fully awere of swinging overlaps, approach controlled signals, etc. If you have no knowledge of signalling principles they can make things complicated. As the original poster commented on his lack of railway knowledge I tried to keep things simple.

[AngryMeerkat]

 

 

No problem

 

A bit more info on AWS & TPWS is found below and as you now apreciate they are not the same. In essense AWS is there to warn drivers whether they will be approching an aspect which requires them to slow down or not. Providing the driver acknowledges the device there is nothing to stop him from continuing at linespeed with potentally fatal results (e.g. the crash at Purley in 1989). TPWS is there to stop the train passing a red signal and cannot be overiden by the driver unless they come to a complete stand and obay certain instructions. However TPWS is not fitted to every signal and moreover it is not active if the signal is showing a proceed aspect (yellow or green) thus AWS is still a usefull device to have around on the railway.

 

AWS = http://en.wikipedia...._inductor_1.JPG

 

Full article = http://en.wikipedia...._Warning_System

 

TPWS = http://en.wikipedia....e:Tpws_loop.jpg

 

Full article = http://en.wikipedia...._Warning_System

 

Thank you for the links and the excellent signalling diagrams, these have really helped a lot. Modelling something is so much easier when you know how it works!

 

It was definitely AWS that I remember as a child, the cab indicator is familiar as I remember the 'sunflower' being visible in engines I was lucky enough to go into. I may use some modellers license and include an AWS magnet on the line running right to left, mount it right next to the bridge with the excuse of it being for the signal at the (offscene) end of the platform.

 

Just a few further questions if I can tap into your knowledge? The article on TPWS doesn't mention when the system was introduced in the UK, would you know roughly when it was? Also you mention 3 aspect signals with 'sub signal', what is the sub signal? I picked up a Traintronics signal brochure today and it lists 3 aspect signals with feather, which is right for the crossover signals, but I can't find a sub signal in the list.

 

Many thanks again for this information, it's helping a lot.

 

Mark

[Edwin_m]

TPWS was introduced around 2000.

 

A subsidiary aspect is similar to a position light shunting signal but it is mounted on the post below a main signal and the only aspect it can show is two white lights for a shunt move (when the red remains lit on the main signal).

[AngryMeerkat]

TPWS was introduced around 2000.

 

A subsidiary aspect is similar to a position light shunting signal but it is mounted on the post below a main signal and the only aspect it can show is two white lights for a shunt move (when the red remains lit on the main signal).

 

Ahh I see, that makes sense. Does the subsidiary aspect signal 'replace' the position light signal, or work in conjunction with it? Would the engine driver see both from his cab, or are they positioned differently for some reason?

 

Thanks Edwin_m, my original thought of 'stop and go' traffic light signals seems to be well and truly wrong!! Thank god for people like you and Phil who know how it all works!

[Edwin_m]

The subsidiary aspect is used where a shunt move starts from a main signal and a position light is used where a shunt move starts somewhere else. Either a subsidiary aspect or a position light signal only authorises the driver to proceed at low speed able to stop short of any obstruction. Reasons to stop might include other trains, hand signals from staff or position light signals. This means that only a subsidiary aspect or a position light signal will ever be used to control entry into a yard or depot. Trains carrying passengers are generally forbidden to proceed on subsidiary or position light aspects, the main exception being at those stations where there are no mid-platform signals but a second train is allowed to enter an occupied platform. Incidentally a subsidiary aspect is approach controlled so will only light when the train is close to the signal.

 

On the other hand if the driver receives a yellow (or better) at a main signal then he knows he had a clear route to the next main signal, though if that route passes position light signals they will also be cleared to show two whites to avoid confusing the driver.

[phil-b259]

Ahh I see, that makes sense. Does the subsidiary aspect signal 'replace' the position light signal, or work in conjunction with it? Would the engine driver see both from his cab, or are they positioned differently for some reason?

 

 

A subsidiary signal is one that is subordinate to the main one just as a Police sergeant is of a higher rank than a police constable, or to think of it another way, the main signal is the one used for the most important routes (Upper class) - the subsidiary is used for less important ones (lower class). Another way to think of it is to imagine a set of traffic lights where you have a green filter arrow, the arrow is your subsidiary signal.

 

Subsidiary signals are always mounted on the same structure as the main signal and are placed as close together as possible and will usually share the same signal identification number. A subsidiary signal contains just two white lights at 45 degrees (normally extinguished)

 

A ‘position light signa’l (officially known as a GPL, the G standing for ground mounted) has three aspects arranged in a triangular fashion and will always be showing either a stop (one red + one white horizontally) or a proceed (two whites at 45 degrees). It will never be located with a main signal and each GPL has its own separate identification number.

 

When a main signal comes off to a proceed aspect it tells the driver that the next section of line (the bit between two main signals where both are able to show a red / stop indication - NOTE, signals not having a red aspect don't count) is completely devoid of trains and can run at the maximum appropriate speed* (Remember the cornerstone of railway signalling being only one train may be permitted into enter the 'block' section between two main signals at any one time).

 

*This will depend on what sort of proceed aspect he gets clearly a yellow means the train must proceed much more cautiously (as the next main signal will be at Red) than if the driver receives a green (where the next main signal will also be at a proceed, i.e. yellow or green)

 

There are times however when you do want to allow two trains to enter the same section of line, for example locomotives moving into a freight yard or sidings to pick up trains, entry to loco depots or stabling sidings where multiple trains may be berthed, at stations to allow a loco to back onto its train or in cases where multiple units are used and you want to combine two trains into one longer unit for its onward journey. This is where the subsidiary signal comes into play. First you bring the approaching train to a stand at the normal red aspect, (the subsidiary signal being blank at all times it is not required). Then after a short delay the subsidiary signal lights up with the two white lights indicating the driver has authority to pass the main red aspect (which stays lit at all times throughout this move) at caution being prepared to stop short of any obstruction OR any other position light / shunt signal displaying a stop (one red and one white horizontally in your era) along their route.

 

As Edwin points out if the main route is set, all intermediate position light / shunt signals between the two main signals will show a proceed (two white lights) but this is not the case with lower class routes where each 'bit' is signalled separately

 

Generally speaking the only time passenger trains will be signalled using a subsidiary signal is at stations where the platform only has one block section and platform sharing is required (some long platforms may be split in two block sections using main signals e.g. Cambridge). Freight trains however do not have such restrictions although the convention is that main signals are used where possible.