BRITISH RAIL CLASS 377

The 'Class 377 Electrostar' electric multiple units were built by Bombardier Transportation (previously ADtranz) at their Derby Works, from 2001 to 2005. The Electrostar family, which also includes Classes 357, 375 and 376, is the most numerous type of EMU built in the post-privatisation period of Britain's railways.
The units are found working suburban services in south London, and rural commuter services to Sussex, Kent and the South Coast, on which they replaced the old 4Cig and 4Vep slam-door stock. Although built in the early 2000s the new units suffered from a plagued introduction: their higher power consumption compared to the slam-door Mark 1-based stock that they replaced led to major upgrades being required to the 750V DC third rail power supply used in the Southern region. The collapse of Railtrack following the Hatfield accident further delayed this upgrade work and the new stock did not begin appearing until 2003.
Class 377s are fitted with external CCTV cameras for driver-only operation.
The Class 377 uses Dellner couplers instead of the Tightlock type originally used on Southern's Class 375s. Southern's 375s were all converted to Class 377 when their Tightlock couplers became redundant after the retirement of the "slam-door" stock such as the Class 421. Note that Southeastern's 375s (sub-classes 375/3, 375/6, and 375/7) were converted to Dellner couplers but not reclassified; their 375/8 and 375/9 units were fitted with Dellner couplers from the start.^[1]
In April 2007, as part of the Route Utilisation Strategy for the Brighton Main Line, it was announced that Southern would obtain an additional 48 Class 377 carriages to replace an identical number of Class 319 carriages (12 4-car units) that will be transferred to First Capital Connect^[2].

Contents

Description

Current operations

Fleet details

References

Description

Like all new trains in the United Kingdom using third-rail power, one carriage in each unit has a recess in its roof where a pantograph could be fitted, so as to allow for future conversion to overhead AC power. Some of the units are actually dual voltage, are fitted with a pantograph and run using it on the West Coast Main Line between Watford and Gatwick Airport.
Despite most units being DC only, the class is numbered in the 3xx series normally used for AC units.

Current operations

★ Brighton Main Line: Brighton–London (various destinations)

★ East Coastway (Brighton–Eastbourne/Hastings)

★ West Coastway (Brighton–Portsmouth/Southampton)

★ Gatwick Main Line London Victoria to Gatwick Airport

★ Redhill-Tonbridge (Tunbridge Wells to Horsham or London Bridge)

★ West London Line (Clapham Junction–Watford Junction)

★ Sutton & Mole Valley Line (Horsham, Guildford & Epsom Downs to London)

Fleet details

Class	Type	Operator	No. Built	Year Built	Cars per Set	Unit nos.	Notes
'Class 377/1'	Express	Southern	64	2002-2003	4	377101-164	These units are mainly used on inner-suburban services to supplement the 46 Class 455 units, and the 24 Class 456s. Also, they are used on the East Grinstead branch, Horsham services and some express services. Class 377101-377120 are all used on mainline routes, class 377121-377139 are used as suburban sets and 377140-377164 are also used on mainline routes.
'Class 377/2'	Express	Southern	15	2003-2004	4	377201-215	Dual-voltage units.These are dedicated to the Brighton - Watford Junction. Also, occasionally used on the London Metro Route
'Class 377/3'	Express	Southern	28	2001-2002	3	377301-328	Converted from Class 375 nos. 375311-338 when "slam-door" stock was retired, and Tightlock couplings became redundant.These are dedicated to the Brighton Express & the west and east coastway lines.
'Class 377/4'	Outer suburban	Southern	75	2003-2005	4	377401-475	-Most routes except inner suburban

References

1. Southern Electrics website
2. More trains arriving on busy rail routes Department for Transport