Lever Operated Signal Boxes controlling Colour Signals

[Whistler40145]

I don’t know much about the Signalling systems on the Network Rail network.

I was thinking, the likes of Kirkham & Wesham Box had levers, controlling Colour Signals.

Was there some mechanism that connected the levers to the electrical circuits?

I look forward to the replies.

 

[Railsigns]

There are circuit controllers attached to the necessary levers below operating floor level. Inside each circuit controller is a shaft that rotates as the lever is moved. A number of copper bands are attached to this shaft and they make contact with electrical contacts when the lever is in the desired position. The bands may be adjusted according to which lever position, or positions, is being proved in the circuit.

 

[Whistler40145]

Many thanks for your reply, it’s very interesting how Victorian system can work with Modern Day technology.

 

[Marklund]

The third picture shows a circuit controller beneath a lever lock (an electrical lock that holds the lever in the frame, and allows it's release when it's energised)
https://www.watercressline.co.uk/article.php/699/nearly-there
https://www.watercressline.co.uk/article.php/699/nearly-there
There are also the circuit controllers, many made by Tyers, used for a similar purpose, attached to the lever by a rod without the lock.
https://flic.kr/p/uifVuT
https://flic.kr/p/uifVuT
These are copper contacts that make up, and the same type are often used for mechanical signal arm indication contacts.

 

[Whistler40145]

Thanks for kindly posting the information

 

[Marklund]

No problem.
(And for clarity, the photos are not mine)

 

[30907]

It isnt (or wasn't) particularly unusual with individual signals - for example, distants were replaced by colour lights when braking distances needed to increase (higher linespeed... ) on the LMR and parts of the SR, and no doubt elsewhere. Fringe boxes to colour light areas would also have some mixed mechanical and electrical locking - Tulse Hill is one that I remember from the 60s, not that I ever saw the interlocking.
.
Levers have a shortened handle to warn the signaller not to apply too much force when pulling.

 

[John Webb]

The LMS in particular carried out fitting 'isolated' colour-light distant signals during the 1930s. There were several reasons for this - it eliminated the maintenance of possibly a mile of wire running over many pulleys at the side of the track, easing the signalman's task, but it also meant that the glow of the colour light signal through fog could be seen much more clearly that a mechanical signal arm. This eliminated the expense of having 'fogmen' sitting by each distant signal in foggy weather to give additional warning by detonators and a hand lamp. At St Albans South signal box, preserved since 2008, we have the original paperwork from 1938 when the mechanical distant signals were replaced by colour-light distants.

Another use of colour-light signals before 'Multiple aspect' signals became commonplace were 'Intermediate Block Signals' (IBS), usually a Home signal and its distant signal an appropriate distance apart, used either to break up a long section to allow more trains to run, or sometimes to replace a signal box which was closed as an economy measure or because sidings it served had been closed.

The south end of the MR Lever Frame at St Albans South - Levers 40 and 44 are the colour-light distant levers, 37 and 41 are the IBS signals for the down lines which were installed when Sandridge Box was closed in the 1960s. Note the lever is coloured both Red and Yellow because it operated two signals - the white band indicates that 'Line Clear' was required from Harpenden box before the signal could be cleared.

 

[36270k]

Levers controlling colour light signals were common on the Southern.
An example would be the box at Horsham.

 

[Railsigns]

Stirling Middle signal box has a 96-lever frame which doesn't control anything mechanically.

 

[Llanigraham]

My Box (Bromfield) had both the Distants converted to colour light, with the top of the lever cut short.

 

[Crossover]

Heaton Norris box near Stockport must be mostly or all electrical signals now, but I believe still has a frame

 

[turboslug]

Helsby box is similar, its 2 distance signals on main line are colour light, station area signals are semaphore, on the hooton branch west cheshire junction (line to fertilizer plant & glass factory & also the now lifted line to mouldsworth) all signals are colour light, i think distant signal into platform 4 at helsby might be semaphore, helsby box took over control of west cheshire junction after its signal box burnt down in early 90s leading to closure of line to mouldsworth, before box burnt down that junction was semaphore operated

 

[edwin_m]

Another reason to convert distant signals to colour light was to allow them to be moved further away, to give more braking distance for faster trains.

The two Stockport boxes and the two at Edgeley Junctions are fully mechancial in operation but as far as I know don't operate anything mechanically. As mentioned, levers working signals or points electrically have shortened handles and this can be seen on the St Albans photo.

 

[MarkyT]

Levers controlling colour light signals were common on the Southern.
An example would be the box at Horsham.

East Kent, until recently, had a number of older full sized lever frames controlling colour lights exclusively, at Ramsgate, Margate etc. Liverpool Lime Street, a Westinghouse "L" style miniature lever frame, was decommisioned recently, leaving (I think) Maidstone East in Kent as the one remaining example of miniature frame technology in active use on NR. Miniature frames have always controlled colour lights or switched power worked semaphores and point machines because the stroke and leverage of the miniature levers is insufficient for mechanical linkages to the trackside. Various types of lever frames controlling colour lights were also a common feature of LU with some curiosities like the Westinghouse "K" style miniature frame at Edgware Road still surviving on the Circle Line, but not for much longer. LU also have their unique interlocking machine rooms on a number of lines, which contain special mechanical frames of Westinghouse "V" style, normally operated automatically or remotely from the control rooms using pneumatic actuators that rotate the interlocking shafts, but also capable of being worked locally in manual in event of communications or sequence machine/computer failure. These all control colour light main running signals and air operated semaphore shunting signals. Interlocking machines were being installed right up until the 1990s!

 

[Crossover]

East Kent, until recently, had a number of older full sized lever frames controlling colour lights exclusively, at Ramsgate, Margate etc. Liverpool Lime Street, a Westinghouse "L" style miniature lever frame, was decommisioned recently, leaving (I think) Maidstone East in Kent as the one remaining example of miniature frame technology in active use on NR. Miniature frames have always controlled colour lights or switched power worked semaphores and point machines because the stroke and leverage of the miniature levers is insufficient for mechanical linkages to the trackside. Various types of lever frames controlling colour lights were also a common feature of LU with some curiosities like the Westinghouse "K" style miniature frame at Edgware Road still surviving on the Circle Line, but not for much longer. LU also have their unique interlocking machine rooms on a number of lines, which contain special mechanical frames of Westinghouse "V" style, normally operated automatically or remotely from the control rooms using pneumatic actuators that rotate the interlocking shafts, but also capable of being worked locally in manual in event of communications or sequence machine/computer failure. These all control colour light main running signals and air operated semaphore shunting signals. Interlocking machines were being installed right up until the 1990s!

I think a miniature frame may exist at Crewe Heritage Centre. It is a few years since I visited (probably about 6 or so years now) but I recall there being something like this back then

 

[Railsigns]

It's worth mentioning that there is another way to control a colour light signal from a mechanical lever frame other than how I described it in post #2.

The alternative method retains the mechanical wire run between signal box and signal. Close to the post of the colour light signal is a short post on which is mounted a weighted lever, such as you would normally find on the post of a semaphore signal. In this instance, however, moving the lever operates an electrical contact box which changes the signal aspect. A benefit of employing this method is that it allows any points beyond the signal to remain mechanically detected.

I've only ever seen this method used at Limerick in Ireland (photo below) but it has been used in the UK in times past.

 

[Railsigns]

I think a miniature frame may exist at Crewe Heritage Centre. It is a few years since I visited (probably about 6 or so years now) but I recall there being something like this back then

There are two. The former Crewe North Junction and Crewe Station 'A' signal boxes are within the heritage centre.

 

[edwin_m]

It's worth mentioning that there is another way to control a colour light signal from a mechanical lever frame other than how I described it in post #2.

The alternative method retains the mechanical wire run between signal box and signal. Close to the post of the colour light signal is a short post on which is mounted a weighted lever, such as you would normally find on the post of a semaphore signal. In this instance, however, moving the lever operates an electrical contact box which changes the signal aspect. A benefit of employing this method is that it allows any points beyond the signal to remain mechanically detected.

I've only ever seen this method used at Limerick in Ireland (photo below) but it has been used in the UK in times past.

This report describes an installation near Manchester and what could go wrong with it!

http://www.railwaysarchive.co.uk/docsummary.php?docID=511

The engine on the Up Fast line passed the colour light home signal, which was wrongly showing a yellow instead of a red aspect, at moderate speed and collided head-on with the 4.5 p.m. Down diesel train from Manchester (Victoria) to Rochdale which was travelling under clcar signals from the branch across its path to the Down Fast line. Trespassers had tampered with the equipment of the Up Fast home signal to make it give the wrong indication : the signalman had failed to set the route ahead of the signal so that the engine could not collide with the diesel train.

Yet another type was a searchlight signal where the moving coloured spectacle plates are operated mechanically by a wire from the box. There's one on the platform at Quorn on the GCR.

 

[John Webb]

.....Yet another type was a searchlight signal where the moving coloured spectacle plates are operated mechanically by a wire from the box. There's one on the platform at Quorn on the GCR.

Here's a photo of it (click on picture to go to the larger original):
Great Central Railway Station, Quorn & Woodhouse

© Copyright Dave Hitchborne and licensed for reuse under this Creative Commons Licence.

 

[A Challenge]

I believe that (at least some) of the Portsmouth Direct is controlled from a leaver box at Haselmere?

 

[LowLevel]

Liverpool Lime Street box lives on until next year

 

[GW43125]

There are two. The former Crewe North Junction and Crewe Station 'A' signal boxes are within the heritage centre.

On the topic of miniature lever frames, a few live on in preservation (Crewe North Jn is virtually intact; part of Crewe South Jn lives on at a miniature railway, as does South Croydon). Lime St and Maidstone East are the only ones left on the mainline (nobody seems sure if Lime St still operates).

 

[Taunton]

The GW had to be different, of course, and remote distants were commonly normal semaphore arms operated by battery motor.

There were ones on the Up lines approaching Taunton station, outer homes (the inner homes were on the big gantry further ahead that appears in so many photos) were operated by wire from the Station West Box. The distants underneath were for the East Box, beyond the station, and were operated by battery, slotted, with the mechanism at the foot of the signalpost.

In clearing them, the Home signal would slam down with a resounding Bang! audible some way away. When East Box pulled off the distant it would very slowly and judderingly, presumably dependent on the state of charge of the battery, take the best part of 10 seconds to go down. Once the train passed the Home would snap back up with equal noise in a moment, while the distant would very slowly return. Friend managed to get a photo of the "impossible" at that moment, with the Home at danger and the Distant underneath at clear.

GW IBS signals used the same approach.

Yet another type was a searchlight signal where the moving coloured spectacle plates are operated mechanically by a wire from the box.

The LNER was an early user of these, initially imported from the USA. Some, especially on the GE electric lines, lasted until recently. They are operated with a U-shaped slide mechanism with the 3 coloured lenses in it, green at one end, yellow at the other, and red in the middle. The aspects are operated by a single pair of electric wires, a positive current pulls the green into position, negative makes it go to the opposite end and show yellow, and appropriate balance weighting of it means with no current it falls to the middle red position.

When TPWS came along a simplistic solution was to attach the operating mechanism to this U-shaped mechanical slide. Unfortunately whoever did the design didn't quite think it through, and early implementations saw the issue that where trains were following one another closely on yellows, it might clear on to green just as the train was passing. The slide would be changing from one end to the other, passing the red on the way, and if the train happened to be crossing the grids at that precise moment it would see the momentary red and get an emergency stop. I believe there had to be a complete redesign of the approach to overcome this.

 

[edwin_m]

Thanks for the info on searchlights - it was very charateristic how they flicked through red on the way from yellow to green but I presume drivers were used to it! Most searchlights were operated electrically as you describe, but I mentioned them particularly because of the few that were worked mechanically.

 

[Railsigns]

But did any of these 'mechanical searchlight' signals use the same searchlight mechanism as the power-operated version? The mechanically operated searchlight signals I've seen details of were actually just a semaphore signal with the blade removed from the spectacle plate and disguised to look like a colour light signal by fitting a black circular board in front.

 

[LowLevel]

On the topic of miniature lever frames, a few live on in preservation (Crewe North Jn is virtually intact; part of Crewe South Jn lives on at a miniature railway, as does South Croydon). Lime St and Maidstone East are the only ones left on the mainline (nobody seems sure if Lime St still operates).

I'm quite sure, it closes next year. I work trains into there regularly and you get advised in the notices of any box closures/recontrol.

The first blockade was prelim work. The only change to Lime Street as it stands (apart from temporary platform 1/2 works) if I recall is platform 8 and a siding or two and points are now out of use and platform 6 starter has been moved a bit closer to the station for sighting as the extra platform length as been removed.

Network Rail's favoured method of renewal now is to overlay the new system on top of the old so civils work aside you can work as normal until you switch the old system off and the new one on. Hence for example the East Notts projects had a fully functioning new system installed with axle counters over the absolute block mechanical signalling.