Signalling for modellers who don't know much about signalling

[big jim]

I'd say the obscured signal is a distant, same as the opposite side

 

it looks to me like a 3 way splitting distant with a section stop signal (possibly for the box in the pic) all 3 distants are for the next 3 boxes on various routes, the homes would be located beyond the junction for each route, i should imagine they would be able to be pulled off once the section in the pic has been pulled off (as I'm sure you can't have the distant off and section on, something to do with the interlocking)

 

I suppose it's also down to drivers route knowledge to know where (and what) the next signal would be depending on which distant they get off

[Compound2632]

I'd say the obscured signal is a distant, same as the opposite side

 

it looks to me like a 3 way splitting distant with a section stop signal (possibly for the box in the pic) all 3 distants are for the next 3 boxes on various routes, the homes would be located beyond the junction for each route, i should imagine they would be able to be pulled off once the section in the pic has been pulled off (as I'm sure you can't have the distant off and section on, something to do with the interlocking)

 

I suppose it's also down to drivers route knowledge to know where (and what) the next signal would be depending on which distant they get off

 

Little Benton box being the box 'in rear' of the junction box - Benton Quarry Junction if I've read the NLS 25" maps correctly.

[beast66606]

The right hand doll - the left one as we are looking - is obscured but assuming it's a distant, which would be logical, then

 

the stop signal would be controlled from the box visible - Little Benton North - and the 3 distants by the next box (the box in advance), each distant arm would correspond to a route through a 3-way junction and would only be cleared when all the stop signals applicable to that route had been cleared, typically this would be the junction signal and a starter on the relevant line but may be more or may be just the junction signal, depends entirely on local circumstances, without a diagram it's not possible to be sure.

 

Splitting distants (as they were called) were provided when the speed through the junction was 40mph or more, on occasion it could be less - there are always exceptions ! - the general idea being to speed the passage of trains as the driver would know he had a clear run through the junction and could clear the main line quicker.

[beast66606]

And here's a (later) shot of the 3 way junction

 

https://www.railscot.co.uk/locations/B/Benton_Quarry_Junction/

[rowanj]

Thanks to all who responded. I think that makes sense... i.e the obscured signal is a distant and is pulled "off" at Benton Quarry when the route is cleared and home signals beyond the bridge from where the shot is taken are cleared. I suppose I had just assumed they were controlled by the box in the photo.. Little Benton North.

 

It will be an interesting piece to construct on the layout...

 

thanks again

 

John

Edited September 28, 2017 by rowanj

[St Enodoc]

Thanks to all who responded. I think that makes sense... i.e the obscured signal is a distant and is pulled "off" at Benton Quarry when the route is cleared and home signals beyond the bridge from where the shot is taken are cleared. I suppose I had just assumed they were controlled by the box in the photo.. Little Benton North.

 

It will be an interesting piece to construct on the layout...

 

thanks again

 

John

If you see a stop signal with a distant (or more than one as here) below it on the same post , the stop signal will be controlled by one box and the distant by the next box in advance. The distant will only come off if the stop signal above it is off. This is usually done by a mechanical arrangement called slotting, although in some cases it could be electrical. It's usually found where boxes are close together.

[micknich2003]

Typical mechanical "Slot"

[Compound2632]

So simple!

 

In the Little Benton case, all three of Benton Quarry Junction's distants will be slotted to Little Benton's signal.

 

Question: Would Benton Quarry Junction have a lever for each of the three distants or would there be some mechanism whereby, having cleared the home and starter for one of the three routes, pulling a single lever would work the appropriate distant?

[The Stationmaster]

So simple!

 

In the Little Benton case, all three of Benton Quarry Junction's distants will be slotted to Little Benton's signal.

 

Question: Would Benton Quarry Junction have a lever for each of the three distants or would there be some mechanism whereby, having cleared the home and starter for one of the three routes, pulling a single lever would work the appropriate distant?

 

A separate lever for each distant - this would make it much simpler for the relevant distant lever to be released (in the interlocking) by the levers working the stop signals to which that distant arm applied.

[micknich2003]

Here is a typical arrangment of splitting distants  at a three way junction.

 

[rowanj]

Thanks again for all the help. As this is likely to be my last layout, I want to get a reasonable, albeit compressed, facsimile of my teenage spotting location. All I remember of that semaphore is the home and distant, which when "off" usually meant a Pacific-hauled Down express. I had no idea that the home off and the distant below it "on" would usually mean a train heading up the Blyth and Tyne.

 

I hoped to make the signals operational, believing I was only needing a few home and distant. It looks like it's going to be more complicated, given that I've never built operational semaphores. Do I take it that the home starter to the left of the gantry protects the exit to the sidings? There is a similar signal at the south end.

 

John

Edited September 28, 2017 by rowanj

[RailWest]

>>> Do I take it that the home starter to the left of the gantry protects the exit to the sidings....

 

Almost certainly yes, but.....it's a STOP signal. It may be a Home or a Starter, but not both :-)

[rowanj]

>>> Do I take it that the home starter to the left of the gantry protects the exit to the sidings....

 

Almost certainly yes, but.....it's a STOP signal. It may be a Home or a Starter, but not both :-)

 

Thanks for the correction to my terminological inexactitude. 

 

Though they will be "off scene" on the layout, do I assume there must have been Stop signals ahead of he actual points at the junction? I always supposed the Home was operated at Liitle Benton North, but a train could only have proceeded to the next Stop signal and I don't recall another junction signal at Benton Quarry. I'm wondering if the Home on the gantry was also operated at Benton Quarry. Need to check the few photos I have when I get home to see what the signalling at Benton Quarry looked like.

[Pacific231G]

A probably very naive question.

In British signalling practice is there a generic name for all the home, starter, advanced starters as opposed to distant and shunting signals? I've seen the term "stop signal" used in this thread but is that an official term and what difference did it make to a driver what sort of "stop signal" he was required to stop at?

Edited October 1, 2017 by Pacific231G

[Colin_McLeod]

The joys of the English language gives us a type of "stop" signal called a "starter".

[RailWest]

The joys of the English language gives us a type of "stop" signal called a "starter".

Just wait until you try to distinguish between a distant which is a 'fixed signal' and a 'fixed' distant :-)

[St Enodoc]

The joys of the English language gives us a type of "stop" signal called a "starter".

A bit like having to click the "Start" button to turn off your computer.

[Pacific231G]

The joys of the English language gives us a type of "stop" signal called a "starter".

It does sound like an anomaly but I suppose it reflects the difference between a signalling system based on positive clearance of trains which can't proceed until a movement is specifically authorised and those based on the driver following a train order unless and until the signals say otherwise. In practice there's obviously a lot of overlap but in the UK it probably led to lightly used lines being rather oversignalled.

[Compound2632]

A probably very naive question.

In British signalling practice is there a generic name for all the home, starter, advanced starters as opposed to distant and shunting signals? I've seen the term "stop signal" used in this thread but is that an official term and what difference did it make to a driver what sort of "stop signal" he was required to stop at?

 

I'm happy to stand corrected by those with more signalling experience but in Midland Style, George Dow refers to "stop and distant arms" - since there is no physical difference between a home and a starter signal arm. But I think there is a considerable difference to the driver - if he's held at the home signal and it clears, he only knows he can draw up as far as the starter; if he's held at the starter and that clears, he knows he has a clear run through the next section. This would be where his route knowledge was all important.

 

EDIT: and that will make a difference to how we operate our model railways - if the signal clears, do we creep forward cautiously or throw the regulator well over and storm away?

Edited October 1, 2017 by Compound2632

[The Johnster]

Whether we creep forward or storm away depends on our own 'route knowledge'; we know that there is another stop signal just beyond the scenic break which is imaginary but the layout only makes sense if we include it, for example.

 

In practice, a driver at a 'home' signal which has cleared and cannot see the 'starter' must assume that it is 'on', and that he must stop at it, until he has a clear view of it, though the signalman may well have 'given him the nod' to speed things along if they are in visible communication with each other.  

Edited October 1, 2017 by The Johnster

[TheSignalEngineer]

Regarding the Distant and Home signals in Absolute Block areas, Distant Off means all signals at that box are Off so you can get a move on to the Distant for the next box  unless you are booked to stop at a station in between. Distant On, prepare to stop at Home signal. If the Home signal is still On when it comes into view then draw up to it. When it clears draw up to the next signal (the old Rule 39A) until you can see the Starter Off. If the first Home is Off when it comes into view then all signals will be Off so keep going, unless the signal is Rule 39A Exempt when you should be prepared to stop at the next signal.  Rule 39A exemption is listed in the Sectional Appendix (used to be Table O on the LM region) so the Driver's action is down to route knowledge.It was allowed in situations where it is undesirable to stop a train if it can be drawn up to the next signal e.g. on a steep rising incline. I remember going to a nice big pile of wagons just outside the Rowley Regis end of Old Hill Tunnel where the train loco stopped but the banker couldn't see the signal was On so kept pushing. 

[The Stationmaster]

A bit like having to click the "Start" button to turn off your computer.

 

How quaint  ( I just click on the drop down menu item which says 'Shut Down' - and it does.

 

Signed Uncle Mac

 

A probably very naive question.

In British signalling practice is there a generic name for all the home, starter, advanced starters as opposed to distant and shunting signals? I've seen the term "stop signal" used in this thread but is that an official term and what difference did it make to a driver what sort of "stop signal" he was required to stop at?

 

We have been there earlier in the thread , and in other threads such as this one (look at post No.60 on the linked page, among other items on the thread) -

 

http://www.rmweb.co.uk/community/index.php?/topic/48504-gwr-signals-and-where-they-go/page-3

 

Semaphore signals which control train running movements come in two varieties -

 

stop signals, at which a train must stop when they are at danger (also known as 'on') and which indicate the line is clear to the next stop signal when they are 'off', i.e. when showing a proceed indication, and

 

distant signals, which show a caution indication when 'on', and which means the stop signals which that distant signal applies to at the next signalbox in advance are at danger, and which when off mean that all stop signals applying to that line at the next signalbox in advance are also 'off'.  The distant signal is placed to allow sufficient distance fora train to be brought to a stand at the first stop signal at the next signalbox in advance.

 

Stop signals are then usually named in accordance with their particular function at a signalbox - usually the first stop signal a train reaches is called the Home Signal although in some naming practices it might be called the Outer Home Signal, the most advanced stop signal at any signalbox is the one controlling entry to the block section in advance and is best known nowadays by the term Section Signal although in normal naming convention it might be the Starting Signal or Advance Starting Signal.  All of these types of signal, including the distant signal, are known as 'fixed signals' - this means they are fixed in one spot whereas a fixed distant signal means its arm is fixed at caution and cannot show a 'clear' indication. 

 

This is a stop signal - in this particular case an upper quadrant signal in which the arm moves upwards when it is off (Pitlochry)

 

 

This is a lower quadrant stop signal (GCR)

 

 

This is a distant signal (albeit lacking the coloured glass in the spectacle plate) and is a lower quadrant signal in which the arm moves downwards to the 'off' position (GCR)

 

 

Stop signals with, in both cases, a lower arm distant signal (which both happen to be Fixed At Caution)  (Bishops Bridge South Devon Railway)

 

 

Stop signal with splitting distant signals (Larbert North) 

 

 

UQ stop signal with lower arm distant - both off (Stirling Middle)

 

Edited October 1, 2017 by The Stationmaster

[The Stationmaster]

Whether we creep forward or storm away depends on our own 'route knowledge'; we know that there is another stop signal just beyond the scenic break which is imaginary but the layout only makes sense if we include it, for example.

 

In practice, a driver at a 'home' signal which has cleared and cannot see the 'starter' must assume that it is 'on', and that he must stop at it, until he has a clear view of it, though the signalman may well have 'given him the nod' to speed things along if they are in visible communication with each other.  

 

An experienced Signalman (on the Western at any rate) would give the Driver the 'Right Away' handsignal in that situation.  (Not in the Rules of course but that was how it was usually done.)

[Compound2632]

An experienced Signalman (on the Western at any rate) would give the Driver the 'Right Away' handsignal in that situation.  (Not in the Rules of course but that was how it was usually done.)

 

... tricky to model.

[The Stationmaster]

... tricky to model.

 

Amusingly many years ago in the 'Railway Modeller' there used to be a series of cartoons which portrayed 'ideas for layouts' which often involved what could best be described as 'animated scenes',  One of them had a signalman on a sort of sliding arrangement who could shoot forwards to give a handsignal from the signalbox window.

 

The odd thing is that in the subsequent 50+ years no manufacturer has copied the idea  (but someone is supposedly copying the swinging water crane arm of course).