Clearing subsidiary signals.

[Grovenor]

 

there is - and as far as I know there has never been an exemption that says drivers may disregard any signal in normal operations. The same principle applies to stacked disc shunt signals by the way.

Try reading the Hull Paragon document in post #21.

Regards

Keith

[Grovenor]

So therefore it follows that regulation 39 (a) must apply to disks ?

The 1950 rule book wording applies rule 39a specifically to Home, Starting and Advanced Starting signals. In normal working it would not be needed for shunt signals. Usually a shunting movement is at or nearly at a stand anyway. And if the signal in rear is a main signal which is released by the disc then the situation needing rule 39a could not occur.

Regards

[ColHut]

So therefore it follows that regulation 39 (a) must apply to disks ?

But reg 34 (Fixed signals) clearly distinguishes between distant, stop, and subsidiary signals. So subsidiary signals are not stop signals as such.

 

Regards

[micknich2003]

Without trawling through hundreds of drawings, Holderness Drain H&BRly, is the only example I'm aware of where a miniature semaphore signal was passed for the main line at Danger. No38.

 

[The Stationmaster]

I stand corrected, I had always assumed facing disks only applied to shutting movements within the limit of shunt , what you now say is that ground disks with red bar have exactly the same status as in effect intermediate running signals , that's a new one

 

So therefore it follows that regulation 39 (a) must apply to disks ?

Some confusion appears to have crept in.

 

Firstly in most semaphore signalled installations running shunting signals were something of a rarity until rationalisation of layouts in the 1960s but they would in any case - where they existed - lead the relevant running signal.  Because they would lead the running signal it would be inevitable that they would have to be cleared before the running signal could be cleared and the running signal could only be cleared if the line was clear to the next running signal (or such other relevant location as, for example, the stop blocks at a terminal platform).  So effectively Rule 39a would not be applicable to a running shunting signal (as other Rules were applicable to it as a shunting signal).

 

The Limit of Shunt only becomes relevant in the case of a movement in the opposite direction to the normal running movement on any line - so obviously a running shunting signal would not exist in such a situation because a running movement would not be permitted  (a running stop signal would have to be provided/exist in order to mark the limiting point of such a movement and might well be fixed at danger).

 

Now going right back to basics a shunting signal (ground disc, miniature semaphore [in some cases], dummy, dolly or whatever you care to call it) is a stop signal irrespective of whether it has a red arm or a yellow arm - and Drivers and Shunters etc have to treat it as such.  When it is in use as a running shunt it is thus obvious that it has to be cleared before the running signal in rear of it otherwise it will present the Driver with a misleading message because the clearance of the running signal conveys a particular 'message' to the Driver (or you get the situation in a failure state such as that explained above by Beast in relation to Liverpool Lime St).

 

BTW I'm not at all sure by what you mean when you talk of an 'intermediate running signal' - there is effectively no such thing in Station Limits (although there could well be a succession of running stop signals) and the term is only used in relation to Intermediate Block Signals.

[phil-b259]

So therefore it follows that regulation 39 (a) must apply to disks ?

No it doesn't because the differentiation in meanings of various signals.

 

A shunt signal merely tells the driver they have authority to proceed. It does not gruntee that the line is clear up to the next signal so drivers must allways proceed at sufficient speed that they are able to stop short of an obstruction.

 

Rule 39 is intended to slow drivers down as they approach a main running signal and indicates that the subsequent main signal is still at danger or that a speed restricted route is to be taken.

 

Thus if driver is approaching a main and shunt signal combo and requires to take the shunt route then rules will require them to either come to a stand before the shunt is cleared or have rule 39 applied to that particular signal only. Subsequent shunt signals will not have rule 39 applied.

[Grovenor]

Mick,

Your extract from the Hull Paragon 1938 document in post #21 covers this issue, the first paragraph on page 323 specifically states that subsidiaries need NOT be observed when proceeding on a main yellow or green, which would imply that they are not always pre-set. (It does specifically say that they are preset for call ons).

The 1950 rule book does not mention presetting facing shunts, or passing them at stop if the main aspect is off. Since it is not in the rule book it is left to the signalling designers and to local instructions. As already mentioned the interlocking will enforce the preset when it is required. The signal plans alone will not usually show this one way or the other, the locking charts, pull plates, or control tables are needed to establish how any particular installation worked. (Except, of course, when you have personal knowledge).

Regards

[ColHut]

Without trawling through hundreds of drawings, Holderness Drain H&BRly, is the only example I'm aware of where a miniature semaphore signal was passed for the main line at Danger. No38.

 

00X HOLDERNESS DRAIN SOUTH 2.jpg

Sorry Mick don't quite follow your terminology.

 

Regards

[Grovenor]

 

Now going right back to basics a shunting signal (ground disc, miniature semaphore [in some cases], dummy, dolly or whatever you care to call it) is a stop signal

I think Junctionmad has been reading the 1950 rule book and the way the signals are described therein, in rules 34 through 48 does clearly seperate Stop signals from Subsidiary signals, the latter being covered in rules 44 to 47. Rule 47 is the one that makes a shunt signal require trains to stop, although in a somewhat convoluted manner! But it does not describe them as 'Stop Signals'.

As always these things vary by company/region etc and by period so it is easy for confusion to creep in when these parameters are not defined. And very few, if any, of us know all of the variations.

Regards

[Grovenor]

Sorry Mick don't quite follow your terminology.

 

Regards

As I noted above, without personal knowledge, or a copy of the locking chart, the plan will not tell you how the facing shunt signal is treated.

My suspicion is that 38 would be released by 37 and hence could not be pulled off for a move from 27 to 24/26 and would need to be ignored by the driver.

Perhaps Mick can confirm.

Regards

[The Stationmaster]

I think Junctionmad has been reading the 1950 rule book and the way the signals are described therein, in rules 34 through 48 does clearly seperate Stop signals from Subsidiary signals, the latter being covered in rules 44 to 47. Rule 47 is the one that makes a shunt signal require trains to stop, although in a somewhat convoluted manner! But it does not describe them as 'Stop Signals'.

As always these things vary by company/region etc and by period so it is easy for confusion to creep in when these parameters are not defined. And very few, if any, of us know all of the variations.

Regards

Ah but Rule 35 makes clear the 'proceed indication' of disc etc signals and Rules 44 - 46 and 47 make very clear the differentiation between Subsidiary Signals and Shunting Signals, and Shunting Signals which are mounted below a stop signal.  As far as I can find the only confusion between Shunting signals and Subsidiary Signals existed in some versions of the 1930s RCH Rule Book but these were - with one exception - clarified by amendments issued in 1937.  The main reason for the ambiguity at that time seems to have been the continuing existence of various Pre-Group shunting and subsidiary signals which had to be explained in as common a manner as possible.

 

In any case you are absolutely correct in that various changes and clarifications took place over the years, including some by amendments to the 1950 Rule Book but even the original print version of that book differentiates quite clearly between Subsidiary Signals (Rules 44 - 46) and Shunting Signals (Rule 47); all that happened in subsequent amendments was an additional clause to Rule 44 referring to Draw Ahead Signals (and we'd best not enter into that jungle).  

[Junctionmad]

Some confusion appears to have crept in.

 

Firstly in most semaphore signalled installations running shunting signals were something of a rarity until rationalisation of layouts in the 1960s but they would in any case - where they existed - lead the relevant running signal.  Because they would lead the running signal it would be inevitable that they would have to be cleared before the running signal could be cleared and the running signal could only be cleared if the line was clear to the next running signal (or such other relevant location as, for example, the stop blocks at a terminal platform).  So effectively Rule 39a would not be applicable to a running shunting signal (as other Rules were applicable to it as a shunting signal).

 

The Limit of Shunt only becomes relevant in the case of a movement in the opposite direction to the normal running movement on any line - so obviously a running shunting signal would not exist in such a situation because a running movement would not be permitted  (a running stop signal would have to be provided/exist in order to mark the limiting point of such a movement and might well be fixed at danger).

 

Now going right back to basics a shunting signal (ground disc, miniature semaphore [in some cases], dummy, dolly or whatever you care to call it) is a stop signal irrespective of whether it has a red arm or a yellow arm - and Drivers and Shunters etc have to treat it as such.  When it is in use as a running shunt it is thus obvious that it has to be cleared before the running signal in rear of it otherwise it will present the Driver with a misleading message because the clearance of the running signal conveys a particular 'message' to the Driver (or you get the situation in a failure state such as that explained above by Beast in relation to Liverpool Lime St).

 

BTW I'm not at all sure by what you mean when you talk of an 'intermediate running signal' - there is effectively no such thing in Station Limits (although there could well be a succession of running stop signals) and the term is only used in relation to Intermediate Block Signals.

Thanks. I used the term intermediate to mean running signals between home and starter , given the use of " intermediate " in signalling terms has other connotations , perhaps a better word is needed

[Junctionmad]

I think Junctionmad has been reading the 1950 rule book and the way the signals are described therein, in rules 34 through 48 does clearly seperate Stop signals from Subsidiary signals, the latter being covered in rules 44 to 47. Rule 47 is the one that makes a shunt signal require trains to stop, although in a somewhat convoluted manner! But it does not describe them as 'Stop Signals'.

As always these things vary by company/region etc and by period so it is easy for confusion to creep in when these parameters are not defined. And very few, if any, of us know all of the variations.

Regards

Correct , partly because I'm signalling an irish layout and CIEs current rule book for semaphores is largely based on the 1950s BR one.

 

Interestingly , on irish railways the practice is the opposite. Facing disks are left on , while main running signals are cleared , is they are ignored unless shunting within signals , perhaps like the widespread adoption of economical FPLs this was an economy measure , or perhaps given the preponderance of single track installations , it was decided to simplify the issue

[Grovenor]

Rules 44 - 46 and 47 make very clear the differentiation between Subsidiary Signals and Shunting Signals, and Shunting Signals which are mounted below a stop signal.

But the headings are arranged so all of these come under the main heading of "SUBSIDIARY SIGNALS" then subdivided into 'Calling-on Signals' - Rule 44, 'Warning Signals' - Rule 45, 'Shunt-ahead Signals' - rule 46 and 'Shunting Signals' - rule 47. Hence shunt signals are part of the class of subsidiary signals, as they are also in the Hull Paragon extract Mick provided.

Regards

[phil-b259]

Try reading the Hull Paragon document in post #21.

Regards

Keith

 

That is news to me - and while I don't doubt that said document reflected the installation in Hull, every single other installation and rule book I have seen does not have such a provision. Thus using the contests of the quoted rule book and extrapolating that to all signalling installations across the country is wrong.

[micknich2003]

Holderness Drain was a new instalation of c1914, it was "Goods Only", 38 read through the Facing X Over, and could not be cleared for the "Main Line". Drivers ignored it, all down to local knowledge, and in fifty years of research, I have seen nothing in writting.

[ColHut]

Gosh, apologies for generating such a 'robust' series of responses!

 

To clarify:

 

1) I appreciate that in practice running shunts in the 1930s, that is shunting signals not co- located with a stop signal, and intended for the control in the right direction, we're probably very rare on double lines, and almost certainly included in signal box special instruction.

 

2) for what it is worth reg16(iii) defines "stop signals" as 'a home, starting, or an advanced starting signal'. This even though shunting signals can 'control' movements as described in regs 47-48.

 

3) My take on the regs is that they are a kind of permission to do something which would otherwise require the permission of relevant person in charge. I note reg 108 - that even if fixed signals are lowered, the driver still needs the nod.

 

4) I assumed that there was something in a work such as 1927 GWR principles of signalling (I made that up). Or BoT requirements for new lines etc that just everyone would point to and say "Ho La this is the relevant bit", but it seems a bit more complicated than that. [ or a pre nationalisation version of maybe Regulations for signalling & signalmen's general instructions - BR 1/10/1960]

 

5) so my remaining questions would be:

 

a) what happens on single lines?

 

b) when actually backing down the line under the instruction of the person in charge - assume double track absolute block - (nothing to do with running shunts now), you find a disc reading to a cross over. Assuming it reads only for the cross over ( I realise there are many permutations), can the signal be passed even if on because it does not apply to the main line. I appreciate the person in charge could have said "go back up 200 yds beyond the shunting disc" which would over ride the disc anyway.

 

My interest here is 1930s LNER really.

 

 

Regards and thanks for your patience.

[Grovenor]

 

Thus using the contests of the quoted rule book and extrapolating that to all signalling installations across the country is wrong.

Quite, the point I was trying to make is that there are very few absolutes in operating rules and signalling that apply everywhere or for all time, and a lot of the info needed to confirm any particular case is either lost or difficult to find.

Regards

[Grovenor]

 

b) when actually backing down the line under the instruction of the person in charge - assume double track absolute block - (nothing to do with running shunts now), you find a disc reading to a cross over. Assuming it reads only for the cross over ( I realise there are many permutations), can the signal be passed even if on because it does not apply to the main line. I appreciate the person in charge could have said "go back up 200 yds beyond the shunting disc" which would over ride the disc anyway.

If backing under instructions from the bobby those instructions must include where to stop. To pass a shunt signal indicating stop the 'instruction' must specifically authorise that. Usually in such a case continueing on the wrong line would take you out of station limits and before the instruction could be given the bobby would need to deal with the formalities under the block regulations.

Incidentally the entries in the rule book are normally referred to as "Rules", calling them regulations is likely to cause confusion with other documents such as the block regulations.

Regards

[ColHut]

If backing under instructions from the bobby those instructions must include where to stop. To pass a shunt signal indicating stop the 'instruction' must specifically authorise that. Usually in such a case continueing on the wrong line would take you out of station limits and before the instruction could be given the bobby would need to deal with the formalities under the block regulations.

Incidentally the entries in the rule book are normally referred to as "Rules", calling them regulations is likely to cause confusion with other documents such as the block regulations.

Regards

I think the bit I was trying to get at was does the shunt signal apply when it is intended to control a movement along the crossover and not the running line. Or is the answer that well it would be a) have a yellow arm in that case, and b) it might only permit moves along the cross over when off, and you need permission of the PIC in other circumstances to go "past" it.

 

Regards and thanks for the comment about "rules".

[Grovenor]

I think the bit I was trying to get at was does the shunt signal apply when it is intended to control a movement along the crossover and not the running line. Or is the answer that well it would be a) have a yellow arm in that case, and B) it might only permit moves along the cross over when off, and you need permission of the PIC in other circumstances to go "past" it.

A shunt signal provided for a crossover is usually red and will be cleared to permit movement over the crossover, ie onto the running line for the correct direction or into a siding, as already said it will not be able to be cleared for a movement continueing on the wrong line unless, a) there is another signal to limit the movement, or b) there is a limit of shunt to limit the movement. (limit of shunts used to be signboards, often illuminated, nowadays often a fixed red aspect). It would be very unusual to find a yellow shunt signal on the running lines, there normal use is to protect siding exits where shunting takes place past the signal into a neck or similar setup and the signal can be ignored until a move needs to exit onto the running lines.

Regards

[The Stationmaster]

Yellow shunt signals are not used on running lines - they are for shunting purposes out of sidings as the Rules have long made clear for the simple reason that they are permitted to be passed in the 'on' position when the points to which they apply are lying normal (i.e. there is no need to obtain the Signalman's permission to pass a yellow arm shunting signal when it is on, even if it is a multi-arm version.

 

As far as shunting signals in running lines are concerned practice has varied over the years and has been very much influenced by interlocking constraints.  In most early designs of interlocking conditional locking was not possible - thus ground shunting signals generally only read for one route in a facing direction through the points to which they applied.  To get round this constraint various alternatives were used and these varied between Companies - for example some used miniature semaphores which allowed a multiplicity of arms, some even used ground signals with an arm for each route (usually two but more in later years) while the GWR adopted the principle of having a white light in those ground shunting signals which could be passed at danger (in normal working) in the authority of the Signalman and provided the unsignalled route red to a signal showing a red light.

 

In later years gradual introduction of conditional locking, or its addition in the form of tappet locking to older designs of frame, allowed a single disc to be cleared for more than one route although it was often the case that for traffic reasons multiple arm discs would be used instead.  However many older installations survived into the 1970s following past company practice but in all cases the meaning of the signals was standardised gradually after the grouping and more or less completely so by the time of the 1950 Rule Book (although there was still the peculiar case of Draw Ahead subsidiary signals - which changed several times in 30 years).

 

Now as far as the operational understanding of signalling is concerned, and the application of the Signalling Regulations, it is important to recognise the distinction between subsidiary signals (i.e. those which are subsidiary to a running stop signal) and shunting signals however it is slightly complicated in some places where shunting signals (usually a miniature semaphore arms are placed in a  subsidiary position to a running signal - normally found on former LNER & LMS lines).  These should however not be confused with co-located shunting signals (usually disc type) which can be found near or even on the same structure as the running signal but are there purely for shunting movements - a situation found commonly on the WR (and sometimes the GWR) and SR although also used on the 'northern Companies/Regions.  Incidentally 'Limit of Shunt' boards/signs seem to have come into use much later - for example they didn't appear on the GWR - as far as I can trace - until sometime between the 1920s and 1930s and are not mentioned at all in earlier minutes regarding procedures for setting back in rear of the Home Signal.

 

To understand a particular situation you need to know something about the movements required to be made to understand the purpose of any shunting signals mounted in this way - hence a locking sketch and a  knowledge of company practice is often just a starting point.

 

As far as 'Principles of Signalling' are concerned the situation varied between the Companies and, until comparatively late on, between BR Regions.  For example the Southern Railway had a set of signalling Principles (published in booklet form) which were in many respects similar to LNER practice.  But at the other extreme the GWR (and WR) did not use 'signalling principles' as such but worked in design terms to a series of 'Drawing Office Instructions' while in all cases what was proposed for any location was subject to the requirements specified by and signalling agreed by the operating dept. 

 

Hope that helps a bit

[RailWest]

>>>Yellow shunt signals are not used on running lines.....

 

Usually....:-)

 

There was one on the No 2 platform road at Cowes, and also one on the bay at the east end of Salisbury. In both cases they were in effect an alternative to a running-shunt. And was it not the case at one time on the LNER that they used yellow discs instead of running-shunts on running lines?

 

Ducks back behind parapet....

[Junctionmad]

I think the bit I was trying to get at was does the shunt signal apply when it is intended to control a movement along the crossover and not the running line. Or is the answer that well it would be a) have a yellow arm in that case, and b) it might only permit moves along the cross over when off, and you need permission of the PIC in other circumstances to go "past" it.

Regards and thanks for the comment about "rules".

In certain cases , ground disks were essentially connected to the point blades and hence you are correct , when off they indicated the diverging route was set

In later years the disc is just a proceed signal, it did not neccessaryily indicate the position of the subsequent turnout.

 

That's my understanding of it anyway

[big jim]

as far as I know there has never been an exemption that says drivers may disregard any signal in normal operations.

 

Not shunt signals but there used to be 2 'black' (ie unlit) signals between sandycroft and mold Jn that you could pass under normal operation, you normally have to stop at an unlit signal (if its possible) or its a spad

 

I'll leave you to guess what they are for, beast66606 will know!!