New Signals to enhace Headway

 
  awsgc24 Minister for Railways

Location: Sydney
Another pair of signals between Gordon and Killara on the Up Shore, hooded out of use for now, will improve headway.

Some three aspect signals may be altered to show four aspects,  including Medium (green over yellow).

Existing three aspect signal, generally have a space for the extra lower yellow light.

For other new signals between Hornsby and Pymble,

see: https://www.railpage.com.au/f-t11397019.htm .

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  gordon_s1942 Chief Commissioner

Location: Central Tablelands of NSW
Of course they could go the way of some American Signaling that allows trains to 'Close Up' in peak hours.
One I read about was on an elevated area and on finding a signal before a platform at STOP (because there was a Train there) to either stop or 'drift past' and close in behind the train ahead and when the Train ahead moved off, follow it in.
I do remember the article that was published in TRAINS showed a picture of just what happened when things didnt go as planned and the following Train ran into the stationary one at the platform.

I have always wondered why Signals are sometimes placed before a platform rather than having them AFTER (non Interlocked locations).
  awsgc24 Minister for Railways

Location: Sydney
I have always wondered why Signals are sometimes placed before a platform rather than having them AFTER (non Interlocked locations).
gordon_s1942
Generally headway is maximised if there is
*A departure signal just past a platform; 20m allows the stationary driver to see this signal without need for a repeater. 20m is about one carriage length.

*B arrival signal a full overlap before that platform. At 80km/h this overlap would be about 400m.

*C additional signals between departure and arrival signals if the section is "long".

*A1 At Hornsby, the up departure signals from Platforms 1 & 2 are right next to the platform, and repeaters are required. This distance cannot be increased because the scissors crossovers are in the way.

*A2 At Hornsby, the down departure signals from Platforms 1 & 2 were actually inside the platforms, because of crossovers, with the recent changes have moved these crossovers out of the way and these signals and crossovers are about 20m away, eliminating the repeaters.

*At Pymble, the Down departure signals are perhaps 100m from the platform, not sure why.

* Between Blacktown and St Marys Up and Down signals are at the same location. At Mt Druitt, one pair of signals are at the preferred departure end of the platform, while the other pair is at the arrival end of the platform. Perhaps this save design costs, but it is stupid nevertheless.
  tazzer96 Deputy Commissioner

Sydney already has some signalling to allow the close up of trains.  I want to tread carefully as I know there are people here who might want to correct me but I know proceeding at danger and the red/red/green aren't technically a close up signal or procedure.

At most automatic signals in Sydney after waiting 30 seconds at stop you can move the train at low speed to the next signal or platform but being cautious enough to stop when you get to the train in front.  

There is also a red over red over green signal aspect which allows you to proceed at low speed but expect to encounter another train.  These exist on both automatic signals and controlled signals which are operating in automatic mode.  I believe a signaller can also turn on this aspect on a controlled signal but I don't think would occur often.  These generally only existexi signals inside the inncercity core.
  nswtrains Chief Commissioner

Sydney already has some signalling to allow the close up of trains.  I want to tread carefully as I know there are people here who might want to correct me but I know proceeding at danger and the red/red/green aren't technically a close up signal or procedure.

At most automatic signals in Sydney after waiting 30 seconds at stop you can move the train at low speed to the next signal or platform but being cautious enough to stop when you get to the train in front.  

There is also a red over red over green signal aspect which allows you to proceed at low speed but expect to encounter another train.  These exist on both automatic signals and controlled signals which are operating in automatic mode.  I believe a signaller can also turn on this aspect on a controlled signal but I don't think would occur often.  These generally only existexi signals inside the inncercity core.
tazzer96
'At most automatic signals in Sydney after waiting 30 seconds at stop you can move the train at low speed to the next signal or platform but being cautious enough to stop when you get to the train in front.'

Except when you end up with a Glenbrook situation.
  awsgc24 Minister for Railways

Location: Sydney
Sydney already has some signalling to allow the close up of trains.  I want to tread carefully as I know there are people here who might want to correct me but I know proceeding at danger and the red/red/green aren't technically a close up signal or procedure.

At most automatic signals in Sydney after waiting 30 seconds at stop you can move the train at low speed to the next signal or platform but being cautious enough to stop when you get to the train in front.  

There is also a red over red over green signal aspect which allows you to proceed at low speed but expect to encounter another train.  These exist on both automatic signals and controlled signals which are operating in automatic mode.  I believe a signaller can also turn on this aspect on a controlled signal but I don't think would occur often.  These generally only existexi signals inside the inncercity core.
'At most automatic signals in Sydney after waiting 30 seconds at stop you can move the train at low speed to the next signal or platform but being cautious enough to stop when you get to the train in front.'

Except when you end up with a Glenbrook situation.
nswtrains
Many if not most signals in the Metropolitan Area, say Sutherland to Cronulla, have "Conditional Clearing" whereby
* An overlap of about 200m is clear of the rear of the preceding train, and
* There is a timed track circuit before the Conditional Signal that Clears from R/R to Green/Red.
* The length of this timing is unknown, but 30 second timer mentioned above may well be a reasonable value.

Note that a Conditionally Cleared signal NEVER authorises a train into an occupied track, unlike Glenbrook, which is a SPAD.
The statement "being cautious enough . . . . " is simply NOT CORRECT.
Low speed R/R/G also have small overlaps. These NEVER authorise a train onto a track occupied by another train.

At Glenbrook, a train passed a Red signal at stop, in accordance with the rules, but failed to travel slow enough to avoid a collision with an earlier train stopped at the next signal due to some kind of signal failure.

Low speeds found between Central, Lidcombe, and Sydenham are different again.
  awsgc24 Minister for Railways

Location: Sydney
The newest to-be-signals on the North Shore Line have black metal plate(s) with an white "X" painted on, rather than a black plastic bag.

Additional signals have appeared between Killara and Lindfield. One of these consist only of a square concrete base which has yet to be buried in the ground. Signal posts do not seem to be simply buried in the ground.
  M636C Minister for Railways

Having looked at the submission for faster trains to Newcastle, the supplied map shows these trains running via the North Shore line. It also shows "Sydney" being located at Milson's Point, but I think that might be an error...

However, if such trains were to run on the "Shore" there would have to be provision for overtaking stopping trains.

This could be done at Chatswood now but this possibility will presumably go away with the conversion to Metro.

St Leonards would allow overtaking if all four platform faces were used, and it would be possible to extend one line as a third track up to but not through Artarmon without much effort.

Lindfield and Gordon could be modified to hold a stopping train while allowing a through train to pass in both directions (but only in one direction at a time unless additional tracks were to be added. The new Lindfield station building and bridge use up clearance that would have allowed a fourth track. Possibly Gordon and Lindfield could be set up to allow overtaking in one direction each....?

The terminating of trains at Gordon and Lindfield during the peak hours would make overtaking difficult.

Adding an extra track through Gordon on the West side might work. There might even be room for a fourth platform if arranged carefully.

Peter
  awsgc24 Minister for Railways

Location: Sydney
A half dozen or so bridges on the North Shore line allow for 4 tracks, including the new bridge over Boundary Road, Roseville.
  awsgc24 Minister for Railways

Location: Sydney
Another pair of signal bases have appeared on the Down Shore between Roseville and Lindfield.
  awsgc24 Minister for Railways

Location: Sydney
Where new signals and track circuits are being installed, temporary fencing is provided. This fencing does NOT have posts dug into the ground, but is clipped to the sleepers so that the distance to the train's loading gauge is perfectly and precisely matched.
  gordon_s1942 Chief Commissioner

Location: Central Tablelands of NSW
Where new signals and track circuits are being installed, temporary fencing is provided. This fencing does NOT have posts dug into the ground, but is clipped to the sleepers so that the distance to the train's loading gauge is perfectly and precisely matched.
awsgc24
When the regulations were published for the erection of Fences it said (my Words) a 'Fence was required for any work site where the work would take longer than 30 minutes' so I rang them up and asked did they need a fence for the Fence if it was going to take longer then 30 minutes for the Fence to be erected?
They Hung UP !!!!.
At the time this was brought in, we had lost a couple to being hit by Trains, one was an experienced rail welder working in the Newnes Jct area who simply stepped back onto the other running line just as an Interurban came past.

Trains dont forgive mistakes..........
  awsgc24 Minister for Railways

Location: Sydney
Where new signals and track circuits are being installed, temporary fencing is provided. This fencing does NOT have posts dug into the ground, but is clipped to the sleepers so that the distance to the train's loading gauge is perfectly and precisely matched.
awsgc24
Since digging a hole into the ballast so as to mount the fence post is probably difficult, and doesn't ensure that the structure gauge is complied with. By comparison the clip-on fence post is rather clever.

Taking photos of these clipon fences is difficult since they are mostly not at platforms or overbridges. Pity that you can no longer lean our of train doors and windows to take such photos. Can any rp-er help?
  M636C Minister for Railways

While this might not be the correct thread, a visit to East Maitland resulted in the impression that a wholesale replacement of signals from Islington Junction to Maitland is under way. The signals are all in place, each immediately behind its predecessor with the heads turned aside and crosses made from white plastic conduit on each post.

I don't imagine that you could move the signals closer and gain anything...

Peter
  awsgc24 Minister for Railways

Location: Sydney
While this might not be the correct thread, a visit to East Maitland resulted in the impression that a wholesale replacement of signals from Islington Junction to Maitland is under way. The signals are all in place, each immediately behind its predecessor with the heads turned aside and crosses made from white plastic conduit on each post.

I don't imagine that you could move the signals closer and gain anything...
M636C
The colour signals around Hanbury Junction date from about 1968.

The colour signals between Hexham and Metford date from about 1973. Why these need replacing after only 45 years is hard to say. It is possible that signal spacing is a bit uneven, because of crossovers that no longer exist. It is possible that occasional double yellows should be replaced by a flashing yellow and then a plain yellow.

While signals on Main and Coal lines are co-located, overlaps and aspect sequences on the Coal lines may be different from the Main lines because AFAIK speed limits on the Coal lines are slower than on the Main Lines.
  awsgc24 Minister for Railways

Location: Sydney
A new/relocated signal has been installed say 400m past SH18.88 which is the departure signal at P1 at Turramurra.

This new signal seems to be much brighter than the signals on either side. The line is straight at the point so that 3 signals can be seen at the same time.

Does this new signal have LEDs while the other two signals are old-fashioned incandescent lights?
  awsgc24 Minister for Railways

Location: Sydney
The X8 and 8X speed boards at the Sydney end of Platforms 1 and 2 at Hornsby have belatedly change to X15,  as explained in another thread.
  awsgc24 Minister for Railways

Location: Sydney
A new/relocated signal has been installed say 400m past SH18.88 which is the departure signal at P1 at Turramurra.

This new signal seems to be much brighter than the signals on either side. The line is straight at the point so that 3 signals can be seen at the same time.

Does this new signal have LEDs while the other two signals are old-fashioned incandescent lights?
awsgc24

AFAIK, there is or should be a rule that LED and incandescent lamps should not be intermixed, lest the brighter one overwhealm the dimmer.

An accident occurred in the UK in say the 1930s, when a driver saw a bright green colour light in the distance and failed to notice a dim semaphore signal immediately ahead. SPAD then collision.
  awsgc24 Minister for Railways

Location: Sydney
South of Turramurra on the Up Shore there are now 3 signals instead of two on this long straight down hill section. They only show 3 positions, and none show G/Y (Medium). There is a new(?) 65km/h speed board at the departure end of the platform.

New signals have a concrete pad at the bottom of the steps, for OHS reasons, but existing signals are not so equipped.

There are some yet-to-be-commissioned extra white warning lights.
  sunnyyan Station Staff

Sydney already has some signalling to allow the close up of trains.  I want to tread carefully as I know there are people here who might want to correct me but I know proceeding at danger and the red/red/green aren't technically a close up signal or procedure.

At most automatic signals in Sydney after waiting 30 seconds at stop you can move the train at low speed to the next signal or platform but being cautious enough to stop when you get to the train in front.  

There is also a red over red over green signal aspect which allows you to proceed at low speed but expect to encounter another train.  These exist on both automatic signals and controlled signals which are operating in automatic mode.  I believe a signaller can also turn on this aspect on a controlled signal but I don't think would occur often.  These generally only existexi signals inside the inncercity core.
tazzer96
Low speed is routinely used at Central on controlled signals on approach to platform 17. There are two controlled signals located before and after the turnout onto Down Shore (plat 16). Normally if there is a train on the platform, the train will be held before the turnout. As the train leaves, the first signal will go to low speed and then the next signal will go to low speed as well.
The low speed trips on the City Circle & Central also help with closeup signalling, but those aren't actually used much. The signal will usually clear before the train needs to slow for the trips.
  awsgc24 Minister for Railways

Location: Sydney
With the remodelling of Hornsby, a short overlap, say 200m, has been provided for Down trains entering Platform 2.

The intermediate timed train stops, 8km/h have therefore been removed.

The speed restriction of 40km/h round the sharp 200m radius curve thus seems to be extended into P2.

The scissors crossovers at the Sydney end of P1 and P2 which were X8, are now X15.
  awsgc24 Minister for Railways

Location: Sydney
With the remodelling of Hornsby, a short overlap, say 200m, has been provided for Down trains entering Platform 2.

The speed restriction of 40km/h round the sharp 200m radius curve thus seems to be extended into P2.
awsgc24
There is now a centre Shore Turnback located past P1 and P2, between the Down Shore-Main and Up Main-Shore. There appear to be new crossovers to allow simultaneous moves to and from P2 and P1, while trains arrive in P1 and Depart P2. However, AFAIK, these two new crossovers DO NOT SEEM to be drawn properly on the "Platform Info Cubicles". The turnback only seems to be connected to P2. Can someone please explain?
  tazzer96 Deputy Commissioner

There is now a crossover (number 528) which is X35 that allows the new turnback siding to head towards platform 1.   Not sure how it will be used operationally or if the current set up will continue just with the slightly faster x15 crossovers south of p1 and p2.
  awsgc24 Minister for Railways

Location: Sydney
There is now a crossover (number 528) which is X35 that allows the new turnback siding to head towards platform 1.   Not sure how it will be used operationally or if the current set up will continue just with the slightly faster x15 crossovers south of p1 and p2.
tazzer96
Crossover 528 seems to be missing from the platform located info kiosks. With this crossover:
* Down Shore trains can shunt from P2 to the Turnback without interfering with any Up Main - P1 trains.
* Up Shore trains can shunt from the Turnback to P1 without interferfering with any P2 - Down Main trains.
* Up Shore trains tend  to leave from P1 more often
* Down Shore trains tend to arrive on P2 more often
* The X15 scissors crossovers then to be less used.

The following places have centre turnback platforms or sidings
* Berowra (P2)
* Hornsby Main (P4)
* Hornsby Shore Turnback (P2-P1)
* Gordon Shore P2
* Lindfield Shore P2
* Chatsword ECRL Turnback (facing north) (P2-P3) - to be deleted with NWRL Metro.
* North Sydney P3 and P4
* There are no longer any non-centre turnbacks on the Shore.

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