SAR Low Speed 3 light signal head?

 
  SAR523 Chief Train Controller

Location: Chicago, IL
Was looking over this signal diagram of Blackwood from some time before the upper quadrant signals were removed:

http://www.signaldiagramsandphotos.com/mywebpages/sa/suburban/1129.pdf

when I noticed the dotted out signal 16B, which appears to be drawn as a 3 light low speed signal.  I have photos showing that Low speed signals 19 & 17 were disc signals, but I don't seem to have any photos that show 16B, and I don't know if I've seen any photos of non-disc low speed-only signals.

Looking around elsewhere on the site, I found other low speed signals drawn the same way here

http://www.signaldiagramsandphotos.com/mywebpages/sa/suburban/BOWDENTOALBERTON431SHEET1.htm

where it looks like all of the signals had been upgraded to 3 light heads.

I'm not seeing anything in the Modelling the Railways of SA convention notes, so I was wondering

a) Does anyone know of these 3 light low speed signals?  Did they start to replace the disc signals, or perhaps were used when clearance was tight (like, for example, between the Up and Down mains between the platforms at Blackwood)

b) Does anyone have any photo references of them?

Thanks in advance!

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  gordon_s1942 Deputy Commissioner

Location: Central Tablelands of NSW
I was drawn to the term 'Low Speed' and I wondered in what context it was used until I saw the diagrams and they are shunting signals which according to the NSW G.A pt 2 are called 'Position Light Shunting Signals.'
They come in 2 styles, one was triangular and the other was vertical, one light on top of the other.
The Triangular case type was both Ground and Mast mounted, depending on its location.
One the triangular version the 2 lights on the bottom display RED while the upper would show Yellow or Amber in most situations.
On top of the case could be mounted 2 or more 'boxes' that displayed a letter indicating what line it was cleared for, like UM for Up Main etc.

I would not be surprised to see that the physical appearance of these signals was the same in both States.
  duttonbay Minister for Railways

Given that the SAR used speed-signalling, unlike NSW, I would expect the signal to have three lights, one above the other. A yellow indication is "low speed (warning?)" and a green is "clear low speed" which means the following signal would be cleared, and would cater for a train which terminated at Blackwood to depart from the down platform to the up line via the "dashed" crossover in the diagram. That scenario and indications fit the rules of speed signalling as implented in SA and Victoria.

However I can't help the OP with any further information specific to Blackwood
  duttonbay Minister for Railways

I think that the lower photo on p308 of "The Overland Railway" shows one of three-light signals, from the rear. I haven't found anything else in that book nor "Line Clear".
  awsgc24 Minister for Railways

Location: Sydney
I was drawn to the term 'Low Speed' and I wondered in what context it was used until I saw the diagrams and they are shunting signals which according to the NSW G.A pt 2 are called 'Position Light Shunting Signals.'
They come in 2 styles, one was triangular and the other was vertical, one light on top of the other.
The Triangular case type was both Ground and Mast mounted, depending on its location.
One the triangular version the 2 lights on the bottom display RED while the upper would show Yellow or Amber in most situations.
On top of the case could be mounted 2 or more 'boxes' that displayed a letter indicating what line it was cleared for, like UM for Up Main etc.

I would not be surprised to see that the physical appearance of these signals was the same in both States.
gordon_s1942

As usual, NSW shunting signals had a complicated history.

The "triangle" (Position Light) shunt signals were first introduced about 1960 at Granville and Gosford, and replaced older electrically operated semaphore "banner" signals enclosed in glass cases. They displayed lights similar to BR signals, and to begin with did not have route indicators where there were more than one route, or the only route was for a wrong line more. The lights were:__
* Stop = red and white horizontal
* Shunt = two white at 45 degrees.

Because of problems with white lamps looking a bit yellow, various shunting and main line signals with white marker lights and the "band of lights" for junctions, were altered to replace the white lights, and the "triangle" shunt signal was altered as follows:--
* Stop = two red lights horizontal.
* Shunt = one yellow light in the top lampcase.

Over several decades, the "triangular" white shunt lamps were converted to the yellow pattern, AFAIK Gosford was the last to be converted.

Gradually route indicators were made universal, though Gosford still has some shunt signals with no route indicators.

When the Tulloch Double Deck trains were introduced in 1964, there was insufficient space between the tracks at 12 foot (3.66m) track centres, and a new design of signal had to be introduced. This was the "dwarf" signal with 3 lamps on top of one another. The top and bottom lamps were red, while the middle lamp was yellow. The is space on the top for no more than
two route indicators, and if more routes are needed, then "miniature multi lamp" route are needed.

If the "triangular" or "dwarf" shunt signals are facing moves on main lines, there will also be a green light when the track is clear to the next main line signal, and the next main line signal is clear. An early such signal at Sutherland in the facing direction has/had no such green light.

The "dwarf" signal case is also used for other purposes, even where track centres are not a problem.
* departure signals at some "automatic" crossing loops on the Broken Line.
** AFAIK, where a "dwarf" departure signal leads to a section not fitted with Rail Vehicle Detection, the yellow light is replaced with a flashing white light.
** See: Yarrabandai - http://www.sa-trackandsignal.net/Pdf%20files/ARTC/AR411.pdf
* co-acting signals, such as Chatswood Platform 3 southbound.


Shunt signals of either kind had one red light (the Marker light) fitted with a series resistor, so that with incandescent lights, it would burn a little less brightly, and take more time to burn-out. This doesn't apply to LED lights.

It is noted that BR has been converting its "triangular" signals to the R/Y/R pattern used by NSW.
  SAR523 Chief Train Controller

Location: Chicago, IL
Thanks for the comments everyone.  Duttonbay - unfortunately I think the shunting lead (and cross over and hence light of interest) were removed from Blackwood prior to the photos that are in "Line Clear".

@gordon_s1942  - as Duttonbay noted, the SAR used American style speed signalling thanks to the rehabilitation that was undertaken under their American Commissioner.  You can see how the arms of a mast were referred to as Normal, Medium and Low speed in the first diagram here:

http://www.johnnyspages.com/rail_dittys_files/sar_signalling/sar_signalling.htm

with the low-speed only single-head disc signals a few diagrams down.  Here also we find no mention of a low speed (ground) 3-light signal, although there are diagrams of colour light signal masts even further down.  Entertainingly, disc and color are spelt US style in this SAR rulebook.
  steam4ian Chief Commissioner

Two and three light ground signals were used on the SAR at may places in lieu of 3 position disc signals. When the Willunga line was duplicated they were installed at Edwardstown, Oaklands and Brighton.
Typically at Brighton three light units were used were used as Up starters for movements from the Down platform road and Siding onto the up line via the trailing-cross over at the up end (much as 16B at Blackwood). A reverse movement from the up line back to the siding or down platform roads was controlled by a two light unit (This signal was located on the Up side of the Jetty Road LX adjacent the "home" signal.
Down movements from the siding to the single main line to Marino were controlled by a three light unit.

Similar principles were used at Edwardstown and Oaklands. As I recall somewhat hazily the movement from the Hills siding back to the loop at Edwardstown was controlled by a two light unit. Movements on the long head shunts at Oaklands were only controlled by a switchstand type indicator rod operated off the mainline turnout which was part of the crossover giving assess to the sidings; indications were red dumbbells and a yellow disc.

When the Tonsley line was built three light ground signals controlled Up movements from the loop to the main line at Tonsley.

Why NSW practice on an SAR site has to be discussed is beyond my understanding.
  duttonbay Minister for Railways

Thanks for the comments everyone.  Duttonbay - unfortunately I think the shunting lead (and cross over and hence light of interest) were removed from Blackwood prior to the photos that are in "Line Clear".
SAR523
That may be the case. In any case almost all of the photos I have found show the down end. Locos watering, an up train framed by the lop bracket signal, that sort of stuff. The up end hardly appears in photos.
  SAR523 Chief Train Controller

Location: Chicago, IL
Thanks for the comments everyone.  Duttonbay - unfortunately I think the shunting lead (and cross over and hence light of interest) were removed from Blackwood prior to the photos that are in "Line Clear".
That may be the case. In any case almost all of the photos I have found show the down end. Locos watering, an up train framed by the lop bracket signal, that sort of stuff. The up end hardly appears in photos.
duttonbay
I have a small number of down end shots courtesy of Des Egan from his research into the station for the convention notes.  Unfortunately all of the ones that might have showed this signal have a train in the way.  Funny that Smile
  SAR523 Chief Train Controller

Location: Chicago, IL
Two and three light ground signals were used on the SAR at may places in lieu of 3 position disc signals. When the Willunga line was duplicated they were installed at Edwardstown, Oaklands and Brighton....
steam4ian

Thanks Ian.  I'll have to go looking.  I did find this in my photos though, which shows the signal in question in place.  Would have been interesting to see the mounting of it, as there was a dense mess  of point and signal rodding running between the tracks in that area.

  steam4ian Chief Commissioner

G'day 523.

Not sure about 16B @ Blackwood but at other locations where either a disc or color light signal was mounted over point rodding the mounting comprised two narrow concrete blocks with a plate bridging the rodding and the signal mounted on the plate.

In my very early tens, early 60 mates and I traversed the hills line stopping off at many of the stations; I was fascinated by the signalling and yard layouts which I have memorised to this day.

The irony is that a later friend who was my best man did join the SAR as a signalling engineer he went on to direct the installation of signalling systems on the iron ore railways and still does consulting work internationally. I went on the specialise in electrical engineering particularly heavy industrial.

Some of the disc signals at Blackwood were two position and wire operated like 19 and 18. Signal 17 was a three position disc because it controlled movements back onto the mainline and thus had a "starting" function.

At one time some trains turned back at Blackwood probably to avoid congestion at Belair hence the trailing cross over 14 with the movement controlled by signal 16B. Because Blackwood had a water column on the down track movement by crossing down trains onto the up platform road allowed a down train to overtake another down train taking water. This was the only place on the suburban network I am aware of this happening even though it would have been possible at places like Mitcham, Edwardstown and Oaklands.
Trains turned back Brighton, the 5:18 ex ARS and I have been told that trains also turned back at Edwardstown, I think it was a movement on a Saturday.
  steam4ian Chief Commissioner

G'day all

Now my turn for a question.

Does anybody recall seeing signal indications according to Rules 131, 132 or 137, 138?

Point of clarification. speed signalling was introduced to the SAR c1913 by Pilkington and Moncrieff at Adelaide yard well before Webb came. The Webb rehabilitation would have hastened its spread but manual LQ semaphores showing route indication persisted until the introduction of CTC or the closure of lines. See Wolseley, Mt Gambier, Tailem Bend, Murray Bridge, Belair, Glanville and Port Adelaide.
Under Webb Hamley Bridge got speed signalling in about 1927 as for Roseworthy, Wasleys and Riverton I can only assume it was about the same time.

Regards
Ian
  duttonbay Minister for Railways

Does anybody recall seeing signal indications according to Rules 131, 132 or 137, 138?
steam4ian
I read somewhere (maybe here!) that those indication were not used in SA.  The medium speed warning at an automatic (permissive) signal is used in Victoria, as part of what is described as 4-aspect signalling.
  cpdbear Assistant Commissioner

Location: Adelaide, South Australia
Does anybody recall seeing signal indications according to Rules 131, 132 or 137, 138?
steam4ian
Single light versions of Rule 137/138 signal existed at Virgina and Two Wells in 1970s. North Adelaide use to have some 131/132 style signals with the bent low speed arms. The only place I remember seeing the double triple light signals was on the Port line, can't recall the actual indications, but the whole line was densely populated with them.
  Heath Loxton Chief Train Controller

Location: Adelaide, SA
Who cares... It is only a silly old signal? Smile
  Pressman Spirit of the Vine

Location: Wherever the Tin Chook or Qantas takes me
Who cares... It is only a silly old signal? Smile
Heath Loxton
Who cares?
Most of the posters in this thread!

They are serious modellers who strive to model railways with an accuracy for certain time periods.

But then that would be beyond some peoples minds to even comprehend.
  gordon_s1942 Deputy Commissioner

Location: Central Tablelands of NSW
Who cares... It is only a silly old signal? Smile
Heath Loxton
Irrespective whether this is about signals that existed and their operation or just for a modeler to put it in the correct place isnt the point.
The Railways ran by their signals in all their various shapes and types and have a history all of their own and although today with most systems trying to eliminate them, they still form an indispensable part of Railway Working.

I wonder when the type of signals were being chosen was their any disputes or favoritism shown by those responsible for doing so.
By Disputes I mean the debacle between the Chief Engineers over the Gauge to be selected for NSW and Victoria which had a long reaching effect when the lines eventually met at the respective borders much sooner than either expected I feel.
  David Peters Dr Beeching

Location: "With Hey Boy".
According to the National Railway Museum website at Port Adelaide the 2 or 3 position dwarf signals were modern replacements for disc signals. So it seems that when replacement was due for a disc signal it was simply replaced with a dwarf electric light signal which would both be easier to maintain and able to be seen better as well as disc signals had very small areas on them for night use. They were mainly used on the Port Line as a low speed indicator to go from a shunting yard back out on to the mainline or a low speed light that you had to stop for account of the SM having to set the level crossing working, well that was how they were used mainly at Kilkenny any way.

The local shunt movement after making up it's train to go to Woodville would pull up to the small colour light signal just before Kilkenny Road  in the yard there and wait, the SM would then set the points to leave and after doing that if it was clear set the level crossing going and finally throw the switch to make the 3 position signal there go to green. Thus the train could slowly come out of the yard over the level crossing and then out onto the mainline to go to Woodville. The Adelaide end was set up the same and also worked by the SM at Kilkenny.

This signal was also used by any shunting train that had to use the head shunt at Kilkenny across Kilkenny Road. There were signals both sides of this level crossing one in the yard and one just before the level crossing on the head shunt.
  SAR523 Chief Train Controller

Location: Chicago, IL
According to the National Railway Museum website at Port Adelaide the 2 or 3 position dwarf signals were modern replacements for disc signals.
David Peters

Thanks David. Can you provide a link to that page on the website?  Mostly just looking for a picture (there or anywhere), but I'd be interested in reading it.
  David Peters Dr Beeching

Location: "With Hey Boy".
Here is the link to the page although it is not very good with the descriptions etc as it is in laymens terms really simplified but there are some photos as well on there!

http://www.natrailmuseum.org.au/lineside.php
  Radioman Train Controller

Hello All,

Re multi aspect signalling . By the early years of the 20th Century a lot of railways globally were having to deal with the problem of better regulating their burgeoning traffic and making better use of their existing infrastructure as in many cases there were physical or economic limits to building more tracks.

Two Position signalling becomes limiting where there is frequent traffic . The are a number of solutions to this and each solution is usually incompatible with the other !

In the case of Victoria and South Australia , American Speed signalling was deemed to be a more flexible solution that British 3 Position Route Signalling . The advent of British 4 Position Signalling in 1924 , whose modern incarnation is used on Queensland Railways and Adelaide Suburban Railways approaches the flexibility of American 3 Position Speed Signalling. ( I will not comment on European multi aspect signalling due to having an extremely limited knowledge of its technicalities and permutations. )

Both Victoria and South Australia use a limited form of Speed Signalling compared to the complexities that have grown up in the US . I understand that Canada also uses a simpler variant of American Speed Signalling.

In Btitish Practice Route Signalling is preferred as it closely aligns with two position practice , nut allows for a higher density of traffic and utilises either multiple adjacent signals just like two position practice or uses various forms of route indicator combined with track speed detection to display the correct indication for the route that is set.

In American Speed Signalling practice the signal indicates the speed parameters for the section ahead and in the process this MAY also indicate which route shall apply , therefore route indicators may or may not be present. In latter years route indicators were usually used to distinguish an approaching route set where the signal speed indication would invariably be the same . Theoretically this should reduce the incidence of train drivers accepting the wrong route , though in practice errors were still made.

In the case of Victoria , Medium Speed Indications restricted line speed to 45 kph unless a 60 light was also present . Medium Speed allowed for increased line capacity in the inner suburbs , the line from Flinders St to Camberwell being the best known example. Alternatively Medium Speed could indicate taking the diverging route at an approaching junction , or it could indicate that the route was set to take the train onto a parallel track.

Like South Australia , Victoria also uses 3 position Low Speeds , though this is rare and is usually present in Goods Yards or Suburban Stabling Sidings where the actual siding is some distance from the shunting line , eg Spencer St to Melbourne Yard .

This is really a subject that requires lots of illustrations and text. I suggest Mark Bau's Victorian Railways Net which gives an interesting rundown.

Hope this helps,

Best wishes and regards, Radioman
  Radioman Train Controller

Hello All,

Re multi aspect signalling . By the early years of the 20th Century a lot of railways globally were having to deal with the problem of better regulating their burgeoning traffic and making better use of their existing infrastructure as in many cases there were physical or economic limits to building more tracks.

Two Position signalling becomes limiting where there is frequent traffic . The are a number of solutions to this and each solution is usually incompatible with the other !

In the case of Victoria and South Australia , American Speed signalling was deemed to be a more flexible solution that British 3 Position Route Signalling . The advent of British 4 Position Signalling in 1924 , whose modern incarnation is used on Queensland Railways and Adelaide Suburban Railways approaches the flexibility of American 3 Position Speed Signalling. ( I will not comment on European multi aspect signalling due to having an extremely limited knowledge of its technicalities and permutations. )

Both Victoria and South Australia use a limited form of Speed Signalling compared to the complexities that have grown up in the US . I understand that Canada also uses a simpler variant of American Speed Signalling.

In Btitish Practice Route Signalling is preferred as it closely aligns with two position practice , nut allows for a higher density of traffic and utilises either multiple adjacent signals just like two position practice or uses various forms of route indicator combined with track speed detection to display the correct indication for the route that is set.

In American Speed Signalling practice the signal indicates the speed parameters for the section ahead and in the process this MAY also indicate which route shall apply , therefore route indicators may or may not be present. In latter years route indicators were usually used to distinguish an approaching route set where the signal speed indication would invariably be the same . Theoretically this should reduce the incidence of train drivers accepting the wrong route , though in practice errors were still made.

In the case of Victoria , Medium Speed Indications restricted line speed to 45 kph unless a 60 light was also present . Medium Speed allowed for increased line capacity in the inner suburbs , the line from Flinders St to Camberwell being the best known example. Alternatively Medium Speed could indicate taking the diverging route at an approaching junction , or it could indicate that the route was set to take the train onto a parallel track.

Like South Australia , Victoria also uses 3 position Low Speeds , though this is rare and is usually present in Goods Yards or Suburban Stabling Sidings where the actual siding is some distance from the shunting line , eg Spencer St to Melbourne Yard .

This is really a subject that requires lots of illustrations and text. I suggest Mark Bau's Victorian Railways Net which gives an interesting rundown.

Hope this helps,

Best wishes and regards, Radioman

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