Style 'N' mechanically locked lever frame

The Westinghouse Brake & Saxby Signal Co. Ltd produced the Style 'N' mechanically locked lever frame from 1931, and a total of 40 units were shipped for use on London Transport underground railways.

The 'N' style frame was a mechanically locked version of the Style 'L' power lever miniature lever frame, it had the mechanical locking situated at the front under the lever instead of the electrical circuit contacts. As a result the electrical circuit contacts {bands} were always placed at the read of the lever frame. From a user point of view the lever frame looked and felt the same as the Style 'L' lever frame. 

The first table in Green, shows all the locations of all frames supplied and installed by Westinghouse Brake and Signal Co. The second table on Yellow lists the preserved Style N lever Frames.

Westinghouse Supplied & Installed Style 'N' Power Lever Frames

Signal Box Name Railway type


Point Levers Signal Levers Special Levers Spare Levers open closed
Acton Town London Transport
119 27 67 0 19 24th January 1932 11th June 1965
Aldgate London Transport
59 14 39 0   19th May 1946 24th Janury1988
Debden London Transport
59       24 1949 29/07/1996.
Ealing Broadway London Transport
55         1952 1974
East Finchley London Transport
35         1935  
(note 1)
London Transport
47 15 29 0 3 14th August 1949 29th July 1996
Finchely Central London Transport
Finchley Road London Transport

N[p/p] push/pull

59 13 24 0 16 25th July 1937 18th January 1987

Grange Hill
(note 2)

London Transport
32         1948 3rd November 1997
Hainault London Transport


83 ? ? ? ? 12th May 1948 21st April 2001
(note 3)
London Transport
35 8 14 1 ? 24th June 1951 still in use OCT 2005
Harrow North London Transport
35         1948  
Harrow South London Transport
35         1948  
Harrow on the Hill London Transport
95         1948 still in use
High Barnet London Transport
35         1948  
Leyton London Transport
23         1947  
Leystonstone London Transport
59         1947 14th April 1997.
(note 4)
London Transport
59         1948 26th August 1997
Neasdon North London Transport
47         1939  
Newbury Park London Transport


59 22 24 8 0 10th December 1947 26th September 1994
North Acton London Transport


11 2 8 ? ? 24th June 1947 2002
Park Junction London Transport
83         1939 25th March 1984
Rayners Lane London Transport


35         1935 1985
Rickmansworth London Transport


47         6th December 1953 still in use 2003
Ruislip Gardens London Transport


22         1948 18th January 1993
Stanmore London Transport
47         1938  
Uxbridge London Transport
59         1938 4th May 1987
West Kensington London Transport


35         1948  
West Ruislip London Transport


orig 59
inst 44
? 14
21st November 1948 18th January 1993
Whitechapel London Transport


47         1951  
White City London Transport
47   14 2 ? 1948  
Willesden Green London Transport
47         1951  
Woodford London Transport
59         1947 26th August 1997.

Note 1 - Epping at commissioning had 11 point levers and 23 signals, prior to commissioning it had been planned to have had a facing point lock (lever 41) but this was never commissioned. Epping also retained block bells until closure of North Weald and Ongar cabins.

Note 2 - Grange Hill frame was (is as it still exists) an N2 even though it was originally (for a few short months) worked prior to Hainult being commissioned.

Note 3. - Hammersmith is still open in 2017

Note 4. - Loughton Cabin is still complete and belongs to the LT museum.

Surviving / Preserved Westinghouse Style 'N' Power Lever Frames

Signal Box Name Railway Parts From


Point Levers Signal Levers Special Levers Spare Levers  Date in use &/or further information
Maryloo Signal Box Bekenscot Model Village Ruislip 22          
Hampton Court Junction Malden DSME Crewe South 12         L Frame
Gloucester Road Junction 12         L Frame
North kent East 35 14 17 2 2 L Frame
White City 35 4 8 - - N Frame

Additional information below, and the best source of information on LT signalboxes can be found at please note that currently I do not intend to duplicate that LT information here.

White City signal cabin
Used an "N" style Westinghouse lever frame. This cabin was one of the fastest on the combine. Oh and incidentally I was a signalman at White City for a spell of time previously having been a Relief Signalman on the Central Line and having been qualified for all the cabins except Bethnal Green and Leyton. Hope this is of some help. Henry Davison.

Just a few notes regarding the LUL style N frames:
The indications for signals are red only, this goes out when the signal clears. If the signal has more than one route there will be a separate lever for each route and a separate red indication for each lever but all will go out when the signal clears. In most cases a more complete signal indication is presented on the diagram including any junction indicators.

Points show the normal and reverse indications and if the extrusion plate for the point has a red label then the points are fitted with point heaters.

There are no block bells in any LUL box the previous exceptions were Harrow on the Hill and Amersham because they worked absolute block to a BR box (Neasden South in the case of Harrow and Great Missenden, Wendover or Aylesbury in the case of Amersham) but these ceased to have block working with the coming of Marylebone IECC.

The train describer receivers were part of the diagram (rather than mounted on the shelf) usually mounted in wings on each end but some times in the main diagram as in the case of the White City photo on the site.

All the LUL N frames had a slightly different lever (as you probably already know) from the L frame in that in front of the catch handle is a protrusion where a small metal plate is fitted with the lever number on. The N frames also had device called "Ball Catch Break" which will cause the lever to disconnect itself from the lever locks and band shaft if the lever is forced against the locking. I have absolutely no idea what this looks like and would love to see it 'cause it seems like a good idea to me.

All LUL frames were larger than the total number of levers by about 2 or 3 feet to accommodate a desk for booking as most (if not all) LUL boxes record train passing times and all LUL boxes have metal cases to the frames because Mr Dell said so (fire precautions).

All LUL diagrams except those in the control rooms show track circuits clear as lit, the opersite of most mainline boxes although both Neasden South (ex GCR) and Earlswood (ex LBSCR) were the same as LUL when I first saw them (in fact Neasden South was until it closed).

I have to say I visited a number of LUL boxes most of them on the spare of the moment and therefore have no pictures, I especially regret not having any pictures of White City as I visited there one Christmas Eve and had a play. I also visited Hammersmith (Met) but never photographed that. Two which I serverely regret are West Ruislip and Finchley Road because these had large N frames with route setting.

I also visited Baker Street (Bakerloo) hidden in a tunnel just off the public area, this frame was a K with just 9 levers but the poor guy working it had to call the station Supervisor to relieve him if he needed the toilet! But my favourite LUL box is Edgware Road which is both the only K frame still in full time regular use now and also one of the few interesting LUL boxes service wise.

I'm sure you know most of the above but I thought as my head was running I'd write it all down as it came. Somewhere I have a picture of West Kensington East IMR which had an N2 frame and if I find it I shall pass it on to you. With thanks to Graham Floyd

Copyright © Mark Adlington 2005-2017
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