British Rail Class 508

The British Rail Class 508 electric multiple units ("EMUs") were built by BREL at York works in 1979-80. They were the fourth variety of BR's then-standard 1972 design for suburban EMUs, eventually encompassing 755 vehicles and five classes (313/314/315/507/508). They have mostly worked on the Merseyrail network since 1983, and continue to do so, now refurbished by Alstom's Eastleigh Works.

British Rail Class 508
Merseyrail Class 508 at Hightown
The interior of a Merseyrail-refurbished Class 508 unit
In service	17 December 1979 – 16 January 2024[1]
Manufacturer	British Rail Engineering Limited
Order no.	30979 (DMSO vehicles) 30980 (TSO vehicles) 30981 (BDMSO vehicles)[2]
Built at	Holgate Road Works, York
Family name	BREL 1972
Replaced	Class 503
Constructed	1979–1980
Refurbished	2002–2004 at Alstom Eastleigh (27 Merseyrail units only) 2007–2008 at Wabtec Doncaster (6 Southeastern units only)[3]
Number built	43
Number scrapped	41
Successor	Class 378 Class 466 Class 777
Formation	As built, 4 cars per unit: DMSO-TSO-TSO-BDMSO After 3-car conversion: DMSO-TSO-BDMSO[2]
Diagram	DMSO vehicles: EA208 TSO vehicles: EH218 BDMSO vehicles: EI203[2]
Design code	4PER[4]
Fleet numbers	508/0: 508001–508043 508/1: 508101–508143 508/2: 508201–508212[5]
Capacity	As built: 320 seats As three-car: 234 seats Three-car modified: 222 seats 508/2 units: 219 seats As refurbished: 192 seats
Owners	Angel Trains[6]
Operators	British Rail Connex South Eastern London Overground South Eastern Trains Merseyrail Southeastern Silverlink
Depots	Birkenhead North (Wirral)[7] Gillingham (Kent) Hall Road (Blundellsands Kirkdale (Liverpool)[2]
Lines served	Wirral line Northern line
Specifications
Car body construction	Steel underframe and body frame, aluminium body and roof
Car length	DM vehs.: 19.800 m (64 ft 11.5 in) Trailers: 19.920 m (65 ft 4.3 in)
Width	2.820 m (9 ft 3.0 in)
Height	3.582 m (11 ft 9.0 in)
Floor height	1.146 m (3 ft 9.1 in)
Doors	Double-leaf pocket sliding, each 1.288 m (4 ft 2.7 in) wide (2 per side per car)
Wheelbase	Over bogie centres: 14.170 m (46 ft 5.9 in)
Maximum speed	75 mph (120 km/h)
Weight	DMSO vehicles: 36.15 t (35.58 LT; 39.85 ST) TSO vehicles: 26.72 t (26.30 LT; 29.45 ST) BDMSO vehicles: 36.61 t (36.03 LT; 40.36 ST)[2]
Traction motors	8 × GEC G310AZ or 8 × Brush TM61-53 (82 kW (110 hp) each, 4 per motor car)
Power output	656 kW (880 hp)
HVAC	Electric heating (ducted warm air)
Electric system(s)	750–850 V DC third rail[2]
Current collector(s)	Contact shoe
UIC classification	Bo′Bo′+2′2′+Bo′Bo′
Bogies	BREL BX1
Minimum turning radius	70.4 m (231 ft 0 in)
Braking system(s)	Electro-pneumatic (disc) and rheostatic[2][5]
Safety system(s)	AWS TPWS
Coupling system	Tightlock
Multiple working	508/3: within subclass, and with Class 313[8] Others: within class, and with Class 507
Track gauge	1,435 mm (4 ft 8 1⁄2 in) standard gauge
Notes/references
Specifications as at August 1982[9] except where otherwise noted. The additional TSO vehicles, removed as part of three-car conversion, were inserted into Class 455/7 units.[2]

508138 bearing the 'Revised' livery, one of six 508s to receive this colourful variant.

A Class 508 in Connex livery leaving Norwood Junction.

508301 arrives at London Euston in October 2007, one month before becoming part of the London Overground fleet.

A Silverlink 508 at South Hampstead.

Related pages

• British Rail Class 507
• Merseyrail