Trolley equipment at Bedale

[John Hinson]

Norman Cadge recorded this as "Trolley Equipment" - does anybody know how it works?


Photo: N L Cadge 22/10/80.

Unfortunately the quality of the original photogrpah does not reveral the detail of the raised lettering in the metalwork.

John

[JRB]

.....apart from the unhelpful "TYER & Co...".

[Mad Mac]

Disclaimer: I’ve never seen one of those before, but might it be the equivalent of a Tokenless Block “Shunting Key”?

[John Hinson]

.....apart from the unhelpful "TYER & Co...".

That's a possibility, given the single line equipment:

Photo: N L Cadge, 22/10/80.

And the contraptions under discussion must be pre-1936 as Leyburn East became Leyburn when the West closed that year.

John

[John Webb]

In Stanley C Jenkins' book "The Wensleydale Branch" (2nd Ed., Oakwood Press 2002, ISBN 0 85361 587 X), it is mentioned that the lengthy loop section through Leyburn was treated as a distinct block section until the 1936 resignalling. Other than an Appendix 3 listing the single line sections and their method of operation in 1931 (Tablet sections from Northallerton West to Aysgarth, Staff sections Northallerton High to Northallerton West, Aysgarth to Hawes Junction (Garsdale)) there is little mention of signalling in the book.

[Mackay]

There is a full description of the system - which was designed to allow a PW trolley to occupy an ETS section without a token - in an issue of Railway Gazette. There were specified locations where the trolley could be taken off the track and an electric plug on the trolley inserted in a fixed socket, and the key turned, to restore token working. Don't have this to hand right now, and need to leave shortly. Will dig it out in due course. The trolley keys appear in auction from time to time.

[John Hinson]

Thnks, Neil, don't break your neck finding the details - that gives me the general background to the system. It seems to have used a lot of wires, though!

It is quite amazing what Norman Cadge spotted and photographed, and indeed remarkable what was still in operation in the 1980s - I don't suppose he knew exactly what he was photogaphing but he recognised its interest.

Me? I didn't even notice it when I went in the box. That being said it was one of those embarrassing times when you enter the box and the signalman's coat is hanging up, his tea is on the table, and his glasses on the train register - but he himself not in sight! It seemed inappropriate to hang about.

Best regards,

John

[Mike Hodgson]

Presumably the two ends of the section have to co-operate in the usual manner order to release the key seen in the lower box in John's photo, this key effectively being a substitute tablet, with key extraction putting the main tablet instruments out of phase.

It would be interesting to see that description if you can find it Neil. As there appears to be room for only one key in the instrument, I am guessing there was only one key for the whole section and (apart from these run-offs) it can go back at either end, as if there were also a similar key at the far end, keys would have to be returned to the originating box. This would not be a problem if there is only one trolley for the line, and you always used it instead of a tablet even if the trolley were working straight through to another section.

[JRB]

Would it put the tablet instruments out of phase? It might just interrupt their line wires.

[John Hinson]

Would it put the tablet instruments out if phase? It might just interrupt their line wires.

Good thought! That could be what the rotary switch in the upper device does.

Pure conjecture, but:

1. Upper device breaks the tablet circuit and activates the bottom instrument
2. The bottom instrument could be just one of several along the section allowing a trolley key to be withdrawn. I would disagree with Mike H - there could potentially be a key in every instrument, except that would preclude the "putting in of one" if there was one already there. It would appear, though, that the trolley normally lived at Bedale so there would be no need to have keys in the mid-section instruments

DB965045. Photo 22/4/81, N L cadge/John Hinson collection.

I wouldn't normally get into locomotives and on-track equipment on this forum but it is worth noting that this is an unusually old specimen - not at all the usual Wickham trolley in general use elsewhere. This could be an indication of its special fittings in connection with the shutting in.

Much of the above is pure guesswork . . . I am sure all will be explained when the Railway Gazette article comes to light.

John

[Andrew Waugh]

There is a full description of the system - which was designed to allow a PW trolley to occupy an ETS section without a token - in an issue of Railway Gazette. There were specified locations where the trolley could be taken off the track and an electric plug on the trolley inserted in a fixed socket, and the key turned, to restore token working. Don't have this to hand right now, and need to leave shortly. Will dig it out in due course. The trolley keys appear in auction from time to time.

'Protection of Trolleys on Single Lines' in the issue of 4 March 1932? This was, indeed, a Tyers system and was a development of the Jacobs system from the GWR.

This system used a switch box at the controlling station feeding a single occupation line wire. The switch box had a four position switch. Position 1 was the normal position with the trolley locked off the line and the line open for train movements. To give permission for a trolley to occupy the line, the signalman turned the switch to Position 2 and the signalman at the other end of the section plunged. If normal polarity was received (tablet in), and the local instrument was normal, this would unlock the switch and it could be placed in Position 4. In this position it fed a current to the occupation line wire which allowed the trolley to be released.

The lineside equipment was a plugbox containing a electromagnetic lock. The trolley had a key/plug box permanently mounted on it. The occupation key was permanently secured to a cable that can be connected between the lineside plugbox and the trolley key/plugbox.

With the trolley off the line, the cable was (electrically) locked in the lineside plugbox, and plugged into the trolley key/plugbox. The key attached to the cable was locked in the trolley key/plugbox, which secured the cable to the plugbox and trolley.

When the signalman sent current to the occupation line wire, this released the key in the trolley key/plugbox, allowing the key to be turned (and optionally removed). This allows a current to be sent from the trolley key/plugbox through the cable to the lineside plugbox. The current on the trolley could be from a battery or a magneto generator. The current from the trolley electrically unlocked the cable from the lineside plugbox and the cable was removed. The trolley is then free!

To clear the line, the ganger plugged the cable into a lineside plugbox. The electric lock automatically engaged, securing the cable in the plugbox. The key is then turned in the trolley key/plugbox, securing the other end of the cable to the trolley. Current was then sent from the trolley, through the occupation line wire to the switch box at the controlling signal box. The signalman turned the switch from Position 4 to Position 3. The received current lifted a lock, and the switch was returned to Position 1. Everything was now free for train movements.

This would explain the upper box in the photo. The lower box is a little more complex.

Note that in the above description, the cable was plugged into the trolley key/plugbox, and could be removed. This allowed the trolley to be used over multiple token sections. When the trolley arrived at the end of the section, the cable (and attached key) was removed from the trolley key/plugbox and taken to the signalbox. The signalbox was fitted with a lineside plugbox and dummy trolley key/plugbox. The cable could be plugged into this dummy plugbox to release the token instruments. The ganger would then be issued with the cable/key for the next section and off they'd go.

*If* this is the system in the photo, then the lower box would be the dummy plugbox with its key present. However, if this is so, the key is present, but the cable is missing. So it might not be this system.

[John Hinson]

[snipped]
*If* this is the system in the photo, then the lower box would be the dummy plugbox with its key present. However, if this is so, the key is present, but the cable is missing. So it might not be this system.

Very interesting, Andrew, thanks.

Bedale was only concerned with one token section because the line was double-track in the other direction but, given that the trolley has been parked up in the yard, would they not have to put the key in somewhere to use the line for normal traffic? Hence the key present in the box.

As for the lack of cable, maybe wear and tear over the years saw its loss and the more usual chain and padlock were subsequently considered to be adequate.

John

[Mike Hodgson]

Many thanks for that Andrew.

Pure conjecture, but:

1. Upper device breaks the tablet circuit and activates the bottom instrument
2. The bottom instrument could be just one of several along the section allowing a trolley key to be withdrawn. I would disagree with Mike H - there could potentially be a key in every instrument, except that would preclude the "putting in of one" if there was one already there. It would appear, though, that the trolley normally lived at Bedale so there would be no need to have keys in the mid-section instruments

I obviously wasn't clear John - that's basically what I was saying, although I thought there could also be a similar control box at the far end, which would be unnecessary if the trolley lived at one end as indicated by your photo.

The number of wires has already been commented on. More than half of them run to the upper box. This makes me doubt that this equipment merely broke the ETS line wire, and Andrew's description confirms that the system interrogated the state of the tablet instrument, which would require several wires.

A circuit diagram would be definitive, and as this system was evidently used on mutiple sections, it may conceivably have been the subject of a LNER standard wiring diagram, but I suppose that is a lot to hope for. This system is clearly quite different from the one Richard Pike used to have set up, also working with Tablet instruments, where the trolley itself carried the equivalent of the lock box and plugged it in at run-offs - essentially the trolley carrying one portable auxiliary instrument to multiple keys rather than one key to multiple auxiliary instruments, which has got to be cheaper. Richard posted these photos a few years back:
http://www.flickr.com/photos/32297024@N ... hotostream
http://www.flickr.com/photos/32297024@N ... hotostream

I am intrigued as to the primary purpose of this cable, which presumably secures the trolley off in a run-off.
It would presumably act as a safeguard against the ganger forgetting to obtain permission to put the trolley back on line.
Would it be only just long enough to prove that the trolley is not foul of the line?
Or is it for more security against any mischevious types who might stumble across the trolley in a run-off and go for a joy ride whilst the line has been reopened to traffic?
This wouldn't be an issue at a manned signalbox of course, so the photo showing the key with no cable need not be anomalous. You would have had to detach the cable to get the trolley into the yard, unless you also had another plug box there. In any case Andrew's description says the cable could be removed for working over multiple sections. Perhaps the key was simply padlocked to the cable, the signalman holding the padlock key?

If this is correct, I suppose the trolley would be issued with a tablet when it ran right through to work on some other section.

[Mackay]

I haven't got the RG article yet, but it will be the one Andrew mentions. I do have a set of NE Area circuit diagrams for the system - 14 drawings altogether dating around 1932 - which are pdf scans and fairly large files. Would be happy to share via Wetransfer if anyone would like copies - send me a PM. Several show the plug cord (5 core) with the key permanently attached to it with a short chain. The single line drawing states "Token (One per Section)" as a note against the cord/key assembly. The key chain could not be removed from the cord as the latter had a plug at each end. The sockets were noted as being "fixed at each occupation box & in signal box".
Neil

[Andrew Waugh]

A little hunting turned up the patent for the system which gives chapter and verse, including a circuit diagram.

UK patent GB375456 issued 30 June 1932 to a James Punter and the well known AE Tattersall:

https://worldwide.espacenet.com/publica ... &KC=A&ND=4

This appears to be Punter's first go:

https://worldwide.espacenet.com/publica ... &KC=A&ND=4