Indian locomotive class WDG-4

The Indian locomotive class WDG-4 (EMD GT46MAC) is a freight-hauling diesel-electric locomotive with AC electric transmission designed by General Motors Electro-Motive Diesel[1] in 1997–1998 for Indian Railways, where they are classed as WDG-4. Derived from the EMD SD70MAC, it is powered by a 4,000 hp (3,000 kW) 16-cylinder EMD 710G3B prime mover. Thirteen were built by EMD as order #958647, and a further eight were exported in kit form and assembled in India. The class entered service in 1999.

WDG-4
GT46MAC - WDG-4s at Castlerock
Type and origin Power type Diesel-electric Builder EMD BLW Model GT46MAC (1997-2007) GT46ACe (2007-2016) JT46ACe (2013-2018) Build date (EMD) 1997–1998 (BLW) 2002–2018 Total produced WDG-4: 1188 WDG-4D: 583 Under License (Production has stopped)
Specifications Configuration: ​  • UIC Co′Co′  • Commonwealth Co-Co Gauge 5 ft 6 in (1,676 mm) Trucks HTSC Length 21.26 m (69 ft 9 in) Height 4.11 m (13 ft 6 in) Axle load 21,000 kg (46,000 lb) Loco weight 126,000 kg (278,000 lb) or 126 t (124 long tons; 139 short tons) Fuel type Diesel fuel Fuel capacity 6,100 Litres Prime mover EMD 16-710G3B Engine type two-stroke V16 diesel Aspiration turbocharged Displacement 186.2 liters (11,360 cubic inches) Alternator TA-17-CA6A AC Traction motors 1 inverter per truck, AC traction motors Cylinders 16 Transmission diesel electric Loco brake Air Train brakes Graduated Release Twin Pipe Air Brake, Dynamic Brakes, Blended
Performance figures Maximum speed 105 km/h (65 mph) Power output 4,000 hp (2,980 kW) / 4,500 hp (3,360 kW) Tractive effort 540 kN (120,000 lbf)
Career Operators Indian Railways, Sri Lanka Railways [as locomotive class M-11, Down-tweaked to 3,250 HP (2.4 MW) using a v12-710 prime mover] Numbers WDG-4 :- 12001 - 12999 & 70001 - 70190 WDG-4D :- 12681 & 70301 - 70882

Further construction has been under license in India by the Banaras Locomotive Works (BLW); more than 60 additional locomotives have been built as of 2006. They are numbered from #12001 upward. A similar type, the EMD GT46PAC, has also been produced for passenger service in India.

As of August 2007, EMD and DLW have begun building GT46ACe's using IGBT technology to replace the older gate turn-off thyristor technology and along with increase of 500 hp, ie, 4,500 hp (3.4 MW), using the Newly tweaked EMD 16N-710G3B-EC, like the passenger WDP-4B have been produced. Newer versions with widened Piggy-face cab profile for enhanced visibility, just like the later variants of WDP-4's and WDP-4B's were also produced.

As of February 2013, DLW began building the Dual Cab version, EMD JT46ACe, called WDG-4D, based on the passenger variant WDP-4D locos, same for both-side visibility. Here again, many features, including IGBT and 4,500 hp have been carried on from the single cab GT46ACe's. The first WDG-4D, numbered 12681, is named "Vijay". Later WDG-4D's were numbered from 70301, as the 12*** series came to an end in 2014 and got switched to 70*** series. Over 1,500 such locomotives, including both WDG-4's and WDG-4D's are currently in operation.