The Southern Railway (SR) in the UK gave the designation SL to the fleet of AC '' overhead'' electric multiple units used on the

South London Line The South London line is a railway line in inner south London, England. The initial passenger service on the route was established by the London, Brighton & South Coast Railway on 1 May 1867 when the central London terminal stations of Victoria ...

between

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and

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. These had been built by the

London, Brighton and South Coast Railway The London, Brighton and South Coast Railway (LB&SCR; known also as the Brighton line, the Brighton Railway or the Brighton) was a railway company in the United Kingdom from 1846 to 1922. Its territory formed a rough triangle, with London at its ...

in 1909, but with the abandonment of the ''Elevated Electric'' service in 1928 they were converted to DC

third rail A third rail, also known as a live rail, electric rail or conductor rail, is a method of providing electric power to a railway locomotive or train, through a semi-continuous rigid conductor placed alongside or between the rails of a railway ...

units.

Construction

The SL (South London stock) units were built in 1909 for use on the LBSCR AC overhead electrified lines in South London. This stock comprised eight three-car units, originally formed Driving Motor Brake Third + Trailer

First First or 1st is the ordinal form of the number one (#1). First or 1st may also refer to: *World record, specifically the first instance of a particular achievement Arts and media Music * 1$T, American rapper, singer-songwriter, DJ, and rec ...

+ Driving Motor Brake Third. They were built by the Metropolitan Amalgamated Carriage & Wagon Company at

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and each motor coach had four Winter Eichberg motors. The Trailer First cars were later removed and used as locomotive-hauled stock, from when the driving cars were paired with former loco-hauled coaches converted to Driving Trailer Composite cars. After the replacement of the AC overhead equipment by the standard SR 660 V DC third-rail system on 17 June 1928, these units were rebuilt. The Driving Motor cars were paired together again to form eight units designated 2SL. The Trailer First cars (which had been out of EMU stock for nearly twenty years) were included in this programme, and were rebuilt into Driving Motor and Driving Trailer pairs to form four units designated 2Wim, for use on the Wimbledon-West Croydon line.

Formations

The LB&SCR purchased sufficient cars for 8 permanent sets, numbered 1E to 8E. However, later Brighton practice was to dispense with fixed sets. When the units were reformed into 2-car sets, 14 driving trailers were provided for 16 driving motor cars, because it was found that the motor cars required more time under maintenance.

References

* * *
Southern Electric Group; SEG Historical Features LBSCR A.C. Fleets
* {{DEFAULTSORT:Sr Class Sl SR SL London, Brighton and South Coast Railway SL Train-related introductions in 1909 Metropolitan Cammell multiple units