Are distant/repeater signals used outside of lever frame worked areas?

[DistantAR3]

The line in the third image in this link looks too modern to me to be worked by lever frame, but there is a distant signal.

Signal Post Signs

 

[skyhigh]

Yes, distant signals are widely used.

 

[swt_passenger]

There are secondary routes with what is usually referred to as two aspect signalling, with relatively long blocks separated by colour signals that can only display red or green, they have green/yellow distants. An example near me is Fareham to St Denys, aka the Netley Line.

I found a thread from 2009, although there may be a better explanation somewhere:

Two Aspect Signals

Railway signalling fascinates me, but one thing that has always made me curious is why certain aspect signals are used. I have a theory, but I don't know if it is correct... From what I can tell, four aspect signals are quite often close together, which is understandable given they are...

www.railforums.co.uk

 

[brad465]

IIRC Box tunnel is a 2-aspect area so has distant signals. As it's a 125mph section of line, this could well be the fastest line to have this signalling arrangement (or joint-fastest if another stretch exists elsewhere).

 

[High Dyke]

Yes. I work a couple of locations where the colour light signals (inc. Distants) are worked by individual switch or can be operated automatically, depending on the aspect of the associated stop signal. You can also get them on NX type signal panels or even on WestCad computer based signalling.

 

[Annetts key]

The Trowbridge line between Bathampton Junction (near Bath Spa) and Hawkridge Junction (between Trowbridge and Westbury) is mostly two aspect colour light signalling. Some of which is controlled by TVSC (computer based interlocking) and some of which is controlled by Westbury Panel (a 1980s PSB).

 

[driver9000]

They aren't limited to mechanical signalling areas. I work exclusively over TCB lines and pass quite a few Distant/Repeater signals controlled on my travels. You can identify them by the letter R, RR or triangle on the number plate.

 

[Taunton]

IIRC Box tunnel is a 2-aspect area so has distant signals. As it's a 125mph section of line, this could well be the fastest line to have this signalling arrangement (or joint-fastest if another stretch exists elsewhere).

The Trowbridge line between Bathampton Junction (near Bath Spa) and Hawkridge Junction (between Trowbridge and Westbury) is mostly two aspect colour light signalling.

The old Western Region seemed to make considerable use of this. I seem to recall that before electrification Didcot to Swindon was 2-aspect, at 125mph, the signals, alternately Distant and Stop, being pretty equidistant apart. I think the same is true for much of the Berks and Hants, especially the west end from Castle Cary to Cogload.

Even if alternate Distants and Stops are at about one mile spacing, at 125mph, two miles a minute, it only takes around one minute for the section to be cleared.

 

[Annetts key]

The old Western Region seemed to make considerable use of this. I seem to recall that before electrification Didcot to Swindon was 2-aspect, at 125mph, the signals, alternately Distant and Stop, being pretty equidistant apart. I think the same is true for much of the Berks and Hants, especially the west end from Castle Cary to Cogload.

Even if alternate Distants and Stops are at about one mile spacing, at 125mph, two miles a minute, it only takes around one minute for the section to be cleared.

The distance between a two aspect colour light distant / repeater and the stop signal it's "repeating" is always at least service braking distance. The distance between the stop signal and the next colour light distant / repeater can be anything. Half a mile or five miles.

In fact, of the original Western Region MAS (multiple aspect signalling) schemes, where the distances have been reviewed for some three aspect signals, where the distances between signals is now deemed excessive, some have been converted to a two aspect signal with a new distant / repeater at service breaking distance from the next stop signal. So some lines now have more two aspect signals than when originally designed!

Meanwhile, at Chipping Sodbury, the long axle counter section through the tunnel as been reduced in length (multiple axle counter sections per line instead of just one per line) allowing more conventional three and four aspect signals in the area compared to before. So less distant / repeater signals.

Many of the bi-directional lines on Western have two aspect signalling for the reversible direction.

 

[louis97]

I seem to recall that before electrification Didcot to Swindon was 2-aspect, at 125mph, the signals, alternately Distant and Stop, being pretty equidistant apart. I think the same is true for much of the Berks and Hants, especially the west end from Castle Cary to Cogload.

Didcot to Swindon (for normal direction of travel) was a mix of 3 and 4 aspect signals long before electrification. The Berks and Hants is also mostly 3 and 4 aspect signals, except as you say the section from Castle Cary to Cogload.

 

[Taunton]

I am surprised the axle counter section through Chipping Sodbury tunnel has been in any way shortened, which would mean equipment inside the tunnel. If I recall correctly the whole reason for putting axle counters in that section was the constant flooding problem in the tunnel, as much for the dislocation this caused to track circuits as any disturbance of the formation. Are there signals now inside the tunnel?

Maybe I should have said "well before electrification" for the 2-aspect Didcot to Swindon installations, the one put in when semaphores were replaced around 1970. Do I recall these were changed again along with the bi-directional signalling being put in?

 

[Annetts key]

I am surprised the axle counter section through Chipping Sodbury tunnel has been in any way shortened, which would mean equipment inside the tunnel. If I recall correctly the whole reason for putting axle counters in that section was the constant flooding problem in the tunnel, as much for the dislocation this caused to track circuits as any disturbance of the formation. Are there signals now inside the tunnel?

Maybe I should have said "well before electrification" for the 2-aspect Didcot to Swindon installations, the one put in when semaphores were replaced around 1970. Do I recall these were changed again along with the bi-directional signalling being put in?

There are still no signals in the tunnel.

Overview of the area and details of the most signifiant changes in the Chipping Sodbury area:

On the main up line between Patchway New Tunnel (the first four aspect signal being outside the west end of the tunnel) and Chipping Sodbury west (105 M/P approx.) the signalling was and still is four aspect.

On the main down line between Chipping Sodbury east (where the main/main crossover is for the entry/exit of the loop is) and Stoke Gifford west / Bristol Parkway the signalling was and still is four aspect.

Note that I'm not including the details for the line towards Filton.

The changes:

As a result of the changes, two new banners were provided between Westerleigh and Chipping Sodbury west, one on the up and one on the down.

Near 105 M/P, the up line signal became a four aspect (previously a four aspect head but only three aspects in use, red, yellow and green).

The down direction signals at the west end of the loop are now all four aspect. Previously the exit signal for the loop was a three aspect.

The up direction signals at the east end of the loop are now three aspect signals. Previously the up line and the exit signal for the loop were three aspect heads but with the yellow aspects blanked out.

Just the other side of the junction, at 104m 13 chains, the down line signal remains a four apect and the reversible signal opposite on the up remains a two aspect (red and yellow). This is also where the start/finish of the earlier axle counter section was. New axle counter heads having been fitted in place of the old heads. Beyond this (towards the tunnel) is the historical section that was considered subject to flooding.

Just before 104 M/P are new axle counter heads.

Near the west tunnel portal, there is a new axle counter head on the down.

Then at the portal, the up line signal is now a fully functional three aspect signal. It was previously a three aspect head with the yellow aspect out of use and showed green regardless of where trains were, only showing red when either the (now removed) tell tale wire was severed, the panel group signals red switch was operated, the panel tunnel special emergency switch was operated or the emergency replacement switch operated. It did not form part of the aspect sequence and was not a block section signal.

There is now a new axle counter head next to this signal and another new axle counter head about 200 yards into the tunnel for the overlap.

At the east (London) end of the tunnel, the only equipment in the tunnel is the existing ATP in-fill beacon and two new AWS (one for each line) replacing the previous AWS (because their position has changed). Near the new AWS are two new axle counter heads.

Outside the tunnel, the previous gantry has gone, all four signals having been replaced with four new signals attached to the walls of the cutting. Theses are around 100 metres nearer (about 101 miles).

The up signal is now a three aspect signal (previously a three aspect head with the red aspect out of use making it a repeater).

The down line signal remains a four aspect. However, previously the red aspect did not form part of the aspect sequence. The signal acting as a repeater. It only showed red when either the (now removed) tell tale wire was severed, the panel group signals red switch was operated, the panel tunnel special emergency switch was operated or the emergency replacement switch operated. It was not a block section signal.

The reversible signal for the up line (down direction) is now a four aspect head but the green aspect is not in use (previously a three aspect head with only a top yellow and bottom yellow aspect, the middle aspect blanked out IIRC making it a repeater).

The reversible signal for the down line (up direction) remains a two aspect (yellow, green) repeater.

At the same location as the new signals there are two new axle counter heads. Also repositioned ATP signal beacons.

The two AWS just east of here for the down direction signals have also been replaced with two new AWS.

At 100¾ M/P is the end of the area that was considered subject to flooding.

Near 99¾ M/P the bracket for both up direction signals has been removed and two new straight post signals have been provided slightly nearer London. The up signal is still a three aspect. The reversible signal is still a two aspect (red, green).

The old location for the bracket was the start/finish for the old axle counter sections. Towards London direction this is where track circuits used to resume (the ASTER U type / SF15 type having been replaced with TI21 / EBI types before the electrification plan was announced).

Near 99¼ M/P the bracket for both down direction signals has been removed and two new straight post signals have been provided. The down signal is now a fully functional three aspect. Previously a three aspect head with the yellow aspect not in use.

The reversible signal is now a three aspect. Previously it was a two aspect head (red, green).

Near 98 M/P the bracket for both down direction signals and the up line signal has been removed. Three new straight post signals have been provided.


No changes to the aspects. Both the up line signal and the down line signals are three aspect types. The reversible signal for the up line (down direction) is a two aspect repeater (yellow, green).

About the flooding. Since the pumps have been installed, as long as they work, the area that floods the most often is now between Chipping Sodbury west (104¾ M/P) through the points for the loop, sometimes through the points for the main to main crossover. Along the loop and sometimes as far as the east end of the loop (about 104¼ M/P).

If the pumps don't work or the amount of water is to much for them, that's when the line floods towards and in the tunnel. Sometimes getting as far as the east (London) end portal.

== Doublepost prevention - post automatically merged: Sunday at 15:57 ==

IIRC Box tunnel is a 2-aspect area so has distant signals. As it's a 125mph section of line, this could well be the fastest line to have this signalling arrangement (or joint-fastest if another stretch exists elsewhere).

Bathampton Junction to Thingley Junction.

Up Main (normal direction)

From Bath Spa, the up main line is three aspect signals until the signal at the west portal of Middle Hill Tunnel (approx. 101¾ M/P) which is a two aspect signal (red, green).

The east (London end) portal of Middle Hill Tunnel (101½ miles) is where the line speed increases from 100 MPH up to 125 MPH.

There are no signals, track circuits or axle counter equipment in Box Tunnel now.

The next signal after Box Tunnel, is a repeater (yellow, green) near the former site of Corsham station, followed by a banner and then a three aspect signal on the approach to Thingley Junction.

Down Main (normal direction)

At Thingley Junction it's three aspect signals until the first signal after the junction. This was a three aspect head but with the middle (yellow) aspect not in use. It has been replaced with a two aspect signal (red, green).

The next signal is a repeater (two aspect, yellow, green) mounted on the wall of the cutting just outside the east (London end) portal of Box Tunnel.

At the other end of the tunnel, just beyond the A4 London Road bridge, is the next two aspect signal (red, green).

The east (London end) portal of Middle Hill Tunnel (101½ miles) is where the line speed reduces from 125 MPH down to 100 MPH.

Then at Shcokerwick, on the approach to Bathampton Junction, there is the last two aspect signal. A repeater (two aspect, yellow, green).

The next signal is a three aspect signal protecting Bathampton Junction.

After that, there are some four aspect signals approaching Bath Spa. Then it's then back to three aspect signalling until the area of St Anne's Park, approaching North Somerset Junction, where it's four aspect signalling for the approaches to Bristol.

Apart from at junctions, most of the reversible signals are two aspect in this area.

Note also that all signals in the areas that I have talked about are now LED type, Dorman Classic Colour Light Signal where mounted on existing structures. Or Dorman Integrated Lightweight Signals.

 

[plugwash]

Another thing you will sometimes see is signals that are technically stop signals, but would only be used to stop a train in unusual circumstances, so effecitvely function as distants most of the time.

Signal 3171 at stevenage controlling access into platform 5 springs to mind. If you route a train to that signal while the platform is occupied you have a "mexican standoff" scenario.

 

[GraphitProjekt]

I believe norwich to diss is 2 aspect + distant signals from trowse junction. Controlled by Colchester psb at 100mph line speed

 

[ex-probationer]

I believe norwich to diss is 2 aspect + distant signals from trowse junction. Controlled by Colchester psb at 100mph line speed

If my memory serves me correctly, 2-aspect, Stop & Distant signals from Trowse Junction to Haughley Junction with a 3-aspect at Diss in the Down Direction.