Semaphore Signals and OLE

[37008]

Whilst reading the excellent "lost railways of Birmingham and the West Midlands" I was surprised to come across a photo of Lichfield City Signal box following completion of the Cross City electrification retaining its Semaphore Signals, and I assume that these Semaphores remained for at least another year until signalling was transferred to Aston PSB in 1992. Generally in the past I had assumed that routes were re signalled with MAS signalling during electrification barring a few oddities such as the remaining ground disks at Stafford and Willesden etc.

 

So my question now is:

 

1. How common was it for routes to retain semaphore signalling post electrification? Was Lichfield City an oddity?

 

2. What design considerations were required when Semaphores were retained in OLE areas? Eg were Faraday cages needed on the ladders / platforms? How far did the signals need to be from return wires? How were they traction bonded?

 

Thanks,

 

Jon

[The Stationmaster]

Semaphores seem to have been near universal on 'earlier' oh electrification schemes right down to the LNER 1500volt schemes although by that time they were not universally retained on running lines (colour lights seemingly being provided as much as anything as part of a concurrent resignalling scheme and for sighting reasons as well as improving line capacity).

 

It was only really the 1960s 25kv schemes that brought significant concurrent abolition of semaphores although resignalling was intended as much for the line capacity and sighting improvements as for staff safety I would think. And of course the bits of West Coast where the signalling was done on the cheap saw retention of ground discs and I think (but the LM experts will know) some siding signals remaining as well but with a protective barrier on the side(s) adjacent to electrified line.

 

Signal Engineer will, I'm sure, be your man for the technical info.

[TheSignalEngineer]

On West Coast electrification the main running lines were virtually all colour light. As Stationmaster said there were many sidings where semaphore signals were retained, including some tall semaphore signals. There were also a few electrified running lines with semaphores, by coincidence I was scanning some pictures this week which included one at Mitre Bridge Junction. After the weekend I will post it.

[LNERGE]

I'm sure just about everything on this diagram was wired... 1500v DC though..

 

http://www.lymmobservatory.net/railways/sbdiagrams/ejleft_sbd_q60.jpg

http://www.lymmobservatory.net/railways/sbdiagrams/ejright_sbd_q60.jpg

[AberdeenBill]

Beautiful diagrams :-) Did the signal on the "From Cortonwood" branch really have four arms (two up, two down) on the same post??

 

Bill

[LNERGE]

It must have at one time to have been drawn like that. This is 18 signal at Elsecar Junction.

 

http://www.flickr.com/photos/13296226@N02/6376974451/

[trisonic]

The old GER lines retained a lot of semaphore signaling after OHLE (well part of that was started before WW2). Most of it didn't disappear until 25kv.

When I returned to Shenfield in the late 70's I was surprised to see semaphores on the old Southend loop line, east of the station (though they didn't last long).

 

Best, Pete.

[TheSignalEngineer]

Promised photo at Mitre Bridge. 'Westie' 47659 waiting for the road after taking over from an 86 in November 1988. I am not sure of the working but I think it was the Liverpool Lime St - Dover Western Docks service, which ran via Birmingham then WCML to Willesden and onto the West London.

 

Photograph Copyright C.E. Steele

 

The signal has short arms as it was fitted with intensified lights, being the first semaphore off the MAS area.

[The Stationmaster]

Promised photo at Mitre Bridge. 'Westie' 47659 waiting for the road after taking over from an 86 in November 1988. I am not sure of the working but I think it was the Liverpool Lime St - Dover Western Docks service, which ran via Birmingham then WCML to Willesden and onto the West London.

Photograph Copyright C.E. Steele

The signal has short arms as it was fitted with intensified lights, being the first semaphore off the MAS area.

That - for a UQ signal - is absolutely delectable. Thank you SE.

[50A55B]

Semaphores survived on the GE Walton branch until relatively recently.

[Fat Controller]

Were/are the Independent Lines at Crewe still signalled with semaphores? I recollect they were, indeed still might be, operated with Absolute Block rather than Track Circuited Block, and wonder if that might be reflected in the type of signal.

[The Stationmaster]

Were/are the Independent Lines at Crewe still signalled with semaphores? I recollect they were, indeed still might be, operated with Absolute Block rather than Track Circuited Block, and wonder if that might be reflected in the type of signal.

I'm fairly sure that some of it at least was colour lights right from the time of electrification.

[beast66606]

I'm fairly sure that some of it at least was colour lights right from the time of electrification.

 

Your memory is correct Mike, all of the remaining bits were converted to colour lights when the power signalling came along.

[LNERGE]

Promised photo at Mitre Bridge. 'Westie' 47659 waiting for the road after taking over from an 86 in November 1988. I am not sure of the working but I think it was the Liverpool Lime St - Dover Western Docks service, which ran via Birmingham then WCML to Willesden and onto the West London.

 

Photograph Copyright C.E. Steele

 

The signal has short arms as it was fitted with intensified lights, being the first semaphore off the MAS area.

 

Some short arms like those featured in the picture..

 

[jeff mcghie]

likely to be some more when the electrification in Scotland kicks off next year. Stirling and Dunblane at least are all still semaphore, think most of the arms around Carmuirs/Larbert have gone now alas.

 

Jeff.

[TheSignalEngineer]

That - for a UQ signal - is absolutely delectable. Thank you SE.

Here it is from the front

 

Photo Copyright C.E. Steele

[LNERGE]

What form did the intensified lights take?

[The Stationmaster]

Here it is from the front

 

Photo Copyright C.E. Steele

Even better - thanks SE

[TheSignalEngineer]

What form did the intensified lights take?

I can't remember offhand as it's about 20 years since I handled one and the scan is inconclusive but from memory I would guess an Adlake intensified light (the small cast body type) with 12v bulb, possibly SL16? No doubt someone will correct me on that shortly.

[AberdeenBill]

OK, if I don't ask, I'll never know... What are the devices indicated by two red lines on points 29 and 30 in he first diagram of Elsecar Jct. above?

 

Thanks

Bill

[jamie92208]

Lancaster Morecambe Heysham was semaphore till mist of the network was closed in 1965. It was electrified at 6.6Kv with Overhead in 1907. The is a photo on my layout thread here Some were raised and some were lowered and others were well out of the way to the side. I do havbe some better photos but need to dig out ones that aren't copyright.

 

Jamie

[beast66606]

OK, if I don't ask, I'll never know... What are the devices indicated by two red lines on points 29 and 30 in he first diagram of Elsecar Jct. above?

 

Thanks

Bill

 

Clearance bars ?

[The Stationmaster]

 

Clearance bars ?

Judging by the way they are linked to facing points/facing point numbers on the diagram I suspect they are probably Facing Point Lock Bars - with an interesting variety of arrangements for such things.

[micknich2003]

Judging by the way they are linked to facing points/facing point numbers on the diagram I suspect they are probably Facing Point Lock Bars - with an interesting variety of arrangements for such things.

I have seen similar arrangments on NE area drawings. In this case, I suggest the close proximity of the level crossing, stops the conventional layout of Lock Bars and Plungers. Instead of the "Lock Bars" being in Rear of the point ends they are instead fixed to the Stock Rails. More to the point, why have "Lock Bars" on 29 points? They are Track Circiuted, a Plunger only should suffice. Best Wishes, Mick.

[Coach bogie]

Semaphores seem to have been near universal on 'earlier' oh electrification schemes right down to the LNER 1500volt schemes although by that time they were not universally retained on running lines (colour lights seemingly being provided as much as anything as part of a concurrent resignalling scheme and for sighting reasons as well as improving line capacity).

 

 

This is Godley Junction where, as Mike Stationmaster says, the semaphores remained on the earlier OH lines. I have a pic taken a few miles further towards Manchester at Dewsnap sidngs of a large braket signal with four posts of small arms with the OHL very close.

 

Regards

 

Mike Wiltshire