1980's signalling for small BLT/Minories

[Lacathedrale]

Hi all,

 

I'm building a layout (see sig) that is based on Bromley North and Purley - the long coal road on the former that runs parallel with the platform loop, and the aggregate conveyor alongside the rear of the platform on the latter. This is a rough system diagram - the grey areas are for now entirely fictional, subject to change, etc.

 

Am I correct in assuming that realistically the signal gantries would primarily be in my inferred left hand section? I am keen to add an extra board to the station, but it would be nice to have just a few bits on the main area.

 

My thoughts were roughly as follows:

 

Down signals:

1a) Outer home to protect the station crossovers in the 'inferred trackwork' on the left to protect that pointwork used for the sidings and crossovers (not pictured)

1b) Home to protect the main station crossovers (not pictured, above signal 2?)

5) Shunting ground signal to permit entry to the loop

 

Up signals:

2) Three aspect as stop + distant to next block section

3) Three aspect as stop + distant, plus shunting signal on top platform for access to London Concrete

4) Three aspect as stop + distant to next stop in this section

 

 

Is this about right? If you have any particular comments about the inferred areas and what they might/should include I'd happily hear it.

Edited October 27, 2018 by Lacathedrale

[Lacathedrale]

I gather there would be some kind of interlocking to prevent contrary movements, i.e. #3 on caution and #1 on green (as pictured?) ?

 

Was there any convention for the use of two or three aspect signals? I gather the latter was when you were representing multiple signals - rather than a stop/distant you would have just a single traffic light that represented all three states - would the justification that the next box's home signal is fairly close be justification for a three aspect at that point, or would it be double aspects all the way?

 

Would there be any of the horns showing different routes? Maybe a horn on #1 to replace #5?

 

Would the siding off the loop and/or Charringtons require signalling individually?

[imt]

I gather there would be some kind of interlocking to prevent contrary movements, i.e. #3 on caution and #1 on green (as pictured?) ?

 

Was there any convention for the use of two or three aspect signals? I gather the latter was when you were representing multiple signals - rather than a stop/distant you would have just a single traffic light that represented all three states - would the justification that the next box's home signal is fairly close be justification for a three aspect at that point, or would it be double aspects all the way?

 

Would there be any of the horns showing different routes? Maybe a horn on #1 to replace #5?

 

Would the siding off the loop and/or Charringtons require signalling individually?

 

The experts are not around at the moment - probably school holiday parent/grandparent duties or the like!  Any way they'll ask you for region and era to give definitive answers.

 

Immediate thoughts:

 

It's not easy to see which way you intend all these signals to be in train travel terms - perhaps lie them down in direction of travel and usually on the left hand side of the line in direction of travel too.  In the UK red (stop/danger) is always at driver eye level - usually the lowermost bulb.

 

If by "horns" you mean feathers - those nice strings of 5 lights which indicate direction then yes some might have them.  You will be told that in slow speed (station) areas it would usually be a route indicator (displaying numeral(s)/letter(s) to identify the route.  I like most others "illegally" use feather signal 'cos I cannot afford to buy ones with route indicators.

 

Feathers are not for shunting.  If you need to call on (say) a loco into a platform which has a train in it you use a Position Light Signal (PLS) which is two lights at an angle below the main head, only lit when calling on and the main aspect is red. I also break rules since I use my PLS with the feathers where there are multiple routes.

 

Shunt signals (GroundPLS - GPLS) are only to control shunt movement and would not normally appear on the main line in the direction of travel. Everything has exceptions.  "Modern" rules say that GPLS that might have several routes have miniature Route Indicators below them with a character/numeral to indicate a route.

 

It is unlikely that you will see mixed up 2/3/4 aspect signals since you should not (for example) show a green when the next signal might be a a more restrictive aspect (red/yellow).

 

Your signal 3 could have a GPLS at its foot for the concrete siding.  Neither 3 nor 4 need a feather UNLESS your two inwards "main" lines are bi-directional - since there is only one route out.

 

I am not sure why signal 2 is there - 3 and 4 could be locked to danger if you were shunting from "next box home" back into the concrete siding (where is the GPLS here?).  What is 5 for? If 1 is your main home signal then there might be 3 feathers to indicate which platform or loop was the destination.  There might be a PLS too.  The signal might also only have red/yellow aspects too since the buffer stop is red - but that is debated still.

 

Signals are only for necessary moves - they are expensive to put in and maintain - so in real life there tend to be fewer than you might think.

 

HTH?......

[Lacathedrale]

Sorry, all the signals are on the right side of the line if you are facing in the direction of travel - is that backwards? I have joined up the signals to the lines and made your suggested changes (details below)

 

 

With regard to mixed two and three  aspect signals - surely at some point you have to have a signal which is green when the next is at yellow, and correspondingly a yellow when the next is red? Otherwise you'd end up with gridlock surely?

 

• By horns I did mean feathers - I guess I could use one on Signal 1 to control access to the loop and sidings, if the desire was such .  Neither 3 nor 4 would get feathers.
• The only reason signal 2 is there, is so it can reflect the status of 'the next box's home signal' which would be somewhere down in my fiddle yard - I assumed that there would be something between the platform signals and the next box's limits?
• Your comment about shunting not being in the direction of travel makes sense, so Signal 5 to be removed - it was to control the access to the loop.
• No 6. added for shunting London Concrete from the up Main connection.
• It seems like that whole blue trackwork is unsignalled - is that OK?

[imt]

All (most unless there are specific sighting problems) UK rail signals appear on the LEFT of the line.  Like the roads we drive on the left.  So you should at least INVERT all your signals.  The more traditional way is to lay them on their side on the line of travel on the left of the line, it's more obvious what they are there for.

 

Your feather reads to the upper platform - no feather reads to the lower one. You maybe need one at 2 o'clock (position4) for the loop which you have marked a s unsignalled - if nothing ARRIVES there then no need for a feather, but I would have thought it might be useful for goods inwards to all your sidings.  You can of course use the platforms - and many places do just that.  Depends on your traffic. If you DO have inwards onto the loop then make the crossover to the left of "Unsignalled" IN only - out/shunt would be direct onto the main line

 

Signal 1 and "Next box home signal" are showing green when they should be red, it is arguable that 1 should not be able to show green since all routes end in stop blocks (with red signals on them) so red/yellow only.  Its unlikely that "Next box home signal" would indeed be 2 aspects - more likely 3 or 4.

 

I still don't understand the purpose of 2.  If you want to protect a train setting back left to right into the concrete siding then 3 and 4 could be locked at danger. There is no need to reflect the status of the next home signal - that can be on your platform starters (3 and 4).  The signal has no apparent purpose other than decoration (so rule 1 applies!) as I cannot see why you would want to stop a train across your station throat still half in a platform???  You wouldn't set out if the routes was not clear. Move it to meet the nest para.

 

If ANYTHING (light engine or train) is leaving the area marked "Unsignalled" towards 2 there MUST be some kind of signal.  Since the line is a main running line it ought to be a main signal. You probably should put it to the left of the turnout for Charringtons.

 

If you are setting wagons back into Charringtons you would again need a GPLS onthe main at signal 2 (reading back into the unsignalled area).

 

Do you want some waffle on permissive working? That's (for example) a light engine to the head of the platform to pull the train out again or a second DMU set following into a half full platform.  That means a PLS on 1 to cover that.

 

Better not do too much until the real experts have said something.  Beefore that though I suggest you have a think about traffic and shunting.

[Lacathedrale]

Thanks again, I've seen the signal diagrams for bromley north and generally it matches what we're discussing and you have said:

 

 

15 protects movement into the goods siding (and 17 protects movement out from the goods sidings into the up main, in yellow?)

25 protects against the catch point (presumably?)

26 (again, in yellow?) and 28 protect against the runaround loop in both directions

 

You were right that there were no other intermediate signals, the next one is that at Sundridge Park (to the left of the telephone icon on the far left of the diagram).

 

The diagramming of signal 22 and 23 is confusing to me. It looks like signal 22 is pinned to both platform faces? If that is the case and 23 refers to the Up siding, what is the point of 25?

 

That said, here is Godstone Rd with the same signal design superimposed (still no idea about London Concrete! or the purpose of 25 and/or the adjacent GPLS)

 

Edited October 28, 2018 by Lacathedrale

[beast66606]

Feathers are not for shunting.  If you need to call on (say) a loco into a platform which has a train in it you use a Position Light Signal (PLS) which is two lights at an angle below the main head, only lit when calling on and the main aspect is red. I also break rules since I use my PLS with the feathers where there are multiple routes.

 

 

LMR 1980s schemes used feathers with shunt routes.

[Dr Gerbil-Fritters]

22 is for platform 2, 23 is for platform 1 - they're are drawn as on a gantry. 22 additionally seems to have some sort of calling on indicator - presumably to allow a move onto the down line in order to reverse into platform 1?

[Lacathedrale]

That icon on 22 is to show it's semi-automatic, which from what I understand means that it will always return to danger based on the train detector circuits?

[beast66606]

That icon on 22 is to show it's semi-automatic, which from what I understand means that it will always return to danger based on the train detector circuits?

 

Yes but more importantly will clear up behind a train based on the TC - it wouldn't be a semi at the platform end of a terminus and the disc could possibly be replaced by a shunt signal under the main aspect as per the signal marked 'C' on the incoming home signal No.5/7

 

Unless you've got a headshunt which you haven't drawn, there should be a trap point on the Charringtons siding and the signal would not be yellow.

 

London Concrete needs a signal protecting the exit in the off scene bit.

 

I assume the (S) means Southern Region or ??

[Lacathedrale]

Hello Beast, if it both cleared and returned to danger based on the TC, wouldn't it be fully automatic? Maybe I'm misunderstanding something!

 

Could I move the ground signal and trap point across from above 'Coal' to the left of the Charrington's siding? That would cover all reasonable shunting moves from the goods sidings I think?

 

What would the off-scene signal look like for London Concrete? I'm presuming it would require a headshunt there since the fragment on-layout is a bit impractical.

[beast66606]

Hello Beast, if it both cleared and returned to danger based on the TC, wouldn't it be fully automatic? Maybe I'm misunderstanding something!

 

Could I move the ground signal and trap point across from above 'Coal' to the left of the Charrington's siding? That would cover all reasonable shunting moves from the goods sidings I think?

 

What would the off-scene signal look like for London Concrete? I'm presuming it would require a headshunt there since the fragment on-layout is a bit impractical.

 

1 - It wouldn't be fully automatic when at a terminus - if it cleared it would stop trains arriving - signals clearing also need the points set.

 

2 - as you have a facing route available into the sidings (mid way along) you will need to move the trap point, change the Charrington signal to red *and* keep the existing signal. I'd favour keeping it red but normally off for the shunt move, then there's no risk of a train shunting back and forth, the points are set the other way and the driver misses this and shunts into a head-on collision.

 

3 - as drawn the signal would be a yellow disc.

[Lacathedrale]

Thanks again Beast, here's what I've come to:

 

[beast66606]

Make the shunt in the sidings (above coaL) red and that looks ok.

 

As I mentioned above you could lose the disk under 22 (reading to London Concrete) and replace it with a pair of white lights "cats eyes" under the main signal but that's your choice.

 

The signals are plated as semis on the prototype diagram because the box can close and the trains will work the signals and points themselves, automatically arriving into and then departing from platform 2 - the box would be open for shunt moves though, so for a model it's likely the "shutting the box facility" would not be provided - it's really for units which simply arrive and depart without fuss.

[RailWest]

As far as I can tell from the plan 'London Concrete' is a siding? In which case, there needs to be a trap-point at the RH end, together with an exit GLS, to protect the platform road.

[Lacathedrale]

Ah, I messed up - the headshunt for London Concrete doesn't run into the platform road, I had my platform in the wrong place. I've tried to fix it, but I think I've made a bunch more mistakes!

 

Edited October 29, 2018 by Lacathedrale

[RailWest]

Well, for a start then, your 'yellow' GLS can no longer be a yellow one!

[beast66606]

Well, for a start then, your 'yellow' GLS can no longer be a yellow one!

 

and the one further to the right on the cement siding can be one !

 

I think you (OP) need to redraw as the plan is quite different.

[RailWest]

and the one further to the right on the cement siding can be one !

 

 

...well, I did wonder about that, but IMHO in such a case there would be a potential for a movement from R to L out of the headshunt that could conflict with a movement coming IN to the concrete siding at the LH end?

[trapoint]

I have followed this story with some interest. I must say that Bromley North was not signalled the same way as most other termini might be. The reason why signal 22 and Sundridge park down starter were plated as semi- automatic is because when the line was re-signalled in 1962 a feature was built into the system there so that during parts of the day the signal cabin there could switch out ( Close). So unless two passenger trains were at the terminus together or a goods train was shunting the goods yard it remained closed. The two signals concerned and points 11 & 18 (Which had electric motors) were automatic. And so during most of the day all passenger trains used platform two point 9 was left set for that route before the signalman closed the box. A train would go past Sundridge park starter which had been showing green and would go back to red as it was passed and would stay that way until the train had departed from the terminus completely. The train would enter the platform and activate the track circuits and a time out would start then points 11 and 18 would change buy themselves and set a route to the up line and then signal 22 would clear. After the train had gone the points and signals would reset themselves ready for the next one.

So unless you want to copy this system you do not need semi-automatic plates on your signals.

[bécasse]

I have followed this story with some interest. I must say that Bromley North was not signalled the same way as most other termini might be. The reason why signal 22 and Sundridge park down starter were plated as semi- automatic is because when the line was re-signalled in 1962 a feature was built into the system there so that during parts of the day the signal cabin there could switch out ( Close). So unless two passenger trains were at the terminus together or a goods train was shunting the goods yard it remained closed. The two signals concerned and points 11 & 18 (Which had electric motors) were automatic. And so during most of the day all passenger trains used platform two point 9 was left set for that route before the signalman closed the box. A train would go past Sundridge park starter which had been showing green and would go back to red as it was passed and would stay that way until the train had departed from the terminus completely. The train would enter the platform and activate the track circuits and a time out would start then points 11 and 18 would change buy themselves and set a route to the up line and then signal 22 would clear. After the train had gone the points and signals would reset themselves ready for the next one.

So unless you want to copy this system you do not need semi-automatic plates on your signals.

 

IIRC (and it is now a long time ago), the reality was even slightly more complicated than that. The Southern habitually used platforms for storing units outside peak-hours and, typically, at Bromley North there would be 10-EPB in platform 1 (which wasn't equipped for auto-working) and 6-EPB in platform 2. So when a down train stopped at Sundridge Park with the Bromley North "home" showing red, a time-out would be started by the occupation of the t/c and by the time the allowed 15 seconds station dwell time had elapsed the calling-on indication (plus the "2" platform indication) would light and the train would proceed, nominally at caution, up the grade and into the London end of platform 2, stopping just short of the stabled units (which would be displaying lit red blinds if fitted or a red tail lamp). Just before the rush hour, an incoming 4EPB would join up with the stabled units once passengers had alighted and would then return to London as 10EPB. If there were no stabled units in platform 2, the train would have received a green at Sundridge Park as previously described.

 

Sometimes, for traffic (or weather) reasons, full length trains would be required right through the day and, on such days, the whole service had to be operated with full length trains to ensure that there were no occasions when 10EPB arrived to find that the only available platform could only take 4EPB because of stabled units!

[Lacathedrale]

I feel well and truly out of my depth now    Tho I won't be able to run 10 carriage trains, a similar thing with 2EPB and 4CEP may be achievable

 

With regard to the diagram, should I consider drawing train patterns first?

 

I think the only thing which pushes it away from real prototype fidelity is that Charringtons comes off at the loop, rather than off the carriage siding.  - The use of the running line as shunting for the gravel plant happened at Purley, for example.

[Downsman John]

I'm afraid that's not correct about Purley.

 

It was (and still is) not possible to access the yard (gravel plant) directly from the main line, the only access is from the down siding. The running lines are far too busy to allow shunting to take place, even if it was possible.

 

Trains normally arrive in the down direction into platform 6, the loco runs round, then draws the train into down siding. Once the train is in the siding all of the shunting takes place from there. When the shunting is complete, the whole train including the loco is contained within the gravel plant as the siding is sometimes used for EMU's if required.

Edited October 30, 2018 by Downsman John

[trapoint]

Yes you are right . I was however just trying to keep things as simple as possible so that readers could understand the way it worked in laymans terms. It did cross my mind what would happen if a train was already parked in platform two I was not sure if the calling-on signal would work without the signalman being present but as you say it could !  During the peak hours the signal cabin was manned and use was made of platform one so there was plenty of lever pulling not to mention when the goods train arrived !  There was nothing high-tech about it though the technology had been around for some time indeed  Bank station on the waterloo& city line could work like this and Watford junction bay platforms were later worked like this after 1967 to name just two. 

After the goods yard and run round loop had been removed at Bromley North I am not sure how often the signal cabin was manned it was still there in the mid seventies even after London bridge power box controlled the rest of the line  but it later closed for good and London bridge then worked the station and very likely with auto working built in as well.

[bécasse]

 It did cross my mind what would happen if a train was already parked in platform two I was not sure if the calling-on signal would work without the signalman being present but as you say it could !

 

The selection of main aspect or calling-on aspect was completely automatic whether the signal box was manned or not. It depended on whether the t/c for the terminal end of the platform was occupied or not. This was a modification of the previous Southern Railway/Southern Region practice where a three-aspect signal was provided which cleared to green if the line was clear to the buffer stops or to single yellow if the platform was partially occupied - I believe that the last new installation of this was the 1957/8 replacement box at Cannon Street, the Kent Coast schemes of 1959-1962 all had calling-on signals which were motorised C-discs on the earlier schemes and position-light on the later ones.