NSB Di 4

NSB Di 4
Type and origin Power type Diesel-electric Builder Henschel Build date 1980
Specifications Configuration: ​  • UIC Co′Co′ Gauge 1,435 mm (4 ft 8+1⁄2 in) Wheel diameter 1,100 mm (3 ft 7 in) Wheelbase 1,850 mm (6 ft 1 in)+2,000 mm (6 ft 7 in) (bogies 15.600 m (51 ft 2.2 in) (between outer axles) Length 20.8 m (68 ft 3 in) Height 4.35 m (14 ft 3 in) Axle load 20 t (20 long tons; 22 short tons) Loco weight 120 t (120 long tons; 130 short tons) Prime mover EMD 16-645E3B Traction motors NEBB QD 335N4A Cylinders V16 Cylinder size 230.2 mm × 254 mm (9.06 in × 10.00 in) bore x stroke Transmission Electric
Performance figures Maximum speed 140 km/h (87 mph) Power output 2,450 kW (3,290 hp) @ 900 RPM Tractive effort 360 kN (81,000 lbf)
Career Operators Norwegian State Railways SJ Norge Number in class 5 Numbers 4.651 – 4.655

NSB Di 4 is a class of five diesel-electric locomotives built by Henschel for the Norwegian State Railways (NSB). Delivered in 1981, the class is used to haul passenger trains on the Nordland Line and are since 2001 the only revenue diesel locomotives used by NSB. The locomotives had electric components from Brown, Boveri & Cie and a General Motors Electro-Motive Division 16-645E prime mover. This gives a power output of 2,450 kilowatts (3,290 hp) and a starting tractive effort of 360 kilonewtons (81,000 lb_f).

The locomotives were ordered in the late 1970s as a supplement and later replacement of the Di 3. The class is technically similar to Denmark's DSB Class ME; it was planned to have commonalities with NSB's electric El 17 locomotives, but this was scrapped. The Di 4 was world's first asynchronous locomotive in revenue service. A second batch was planned delivered later in the 1980s, but the order was never placed.