The Indian locomotive classWDG-3A is a class ofdiesel–electric locomotive that was developed in 1994 byBanaras Locomotive Works (BLW),Varanasi forIndian Railways. The model name stands forbroad-gauge (W), Diesel (D), Goods traffic (G) engine, 3,100 hp (3A) locomotive. They entered service on 18 July 1995. A total of 1,164 WDG-3A units were built between 1994 and 2015 atBLW, Varanasi with a few units being produced byDiesel Loco Modernisation Works (DLMW) and Parel Workshop.

WDG-3A
Ludhiana based WDG-3A at Jalandhar City.
Type and origin Power type Diesel Builder BLW, Diesel Loco Modernisation Works Model ALCO-251C/ALCO DL560C variant Build date 1994–2015 Total produced WDG-3A: 1,998 Rebuilder Diesel Loco Modernisation Works, Patiala
Specifications Configuration: ​  • UIC Co-Co Gauge 1,676 mm (5 ft 6 in) Bogies High adhesion Fabricated bogies Wheel diameter 1,092 mm (3 ft 7 in) Wheelbase 12.834 m (42 ft1+1⁄4 in) Length 17.85 m (58 ft6+3⁄4 in) Width 3.016 m (9 ft10+3⁄4 in) Height 4.162 m (13 ft7+7⁄8 in) Axle load 23,500 kg (51,800 lb) Loco weight 127 t (125 long tons; 140 short tons) Fuel type Diesel Fuel capacity 6,000 L (1,300 imp gal; 1,600 US gal) Prime mover ALCO 251-C RPM range 400–1050 RPM Engine type V16Diesel engine Aspiration ABB VTC304-15 orNapier NA 295 IRturbocharger Traction motors BHEL TA 10102 CW (new), BHEL TG 10931 AZ(old) Cylinders 16 Cylinder size 228 mm × 266 mm (8.98 in × 10.47 in) bore xstroke Transmission Diesel electric MU working 2 Loco brake Air dynamic brake Train brakes Air,Vacuum andDual
Performance figures Maximum speed 105 km/h (65 mph) Power output WDG-3A: 3,100 hp (2,300 kW) Tractive effort 37.90 t (37 long tons; 42 short tons) Factor of adh. 0.33
Career Operators Indian Railways Numbers 14501-14999, Newer13000-13665 Nicknames Shakti, Prabal, Jai Jawan Locale throughout Indian Railways First run 1994 Retired Early 2020s–present Preserved 1[citation needed] Disposition In service

It is the dedicated freight version of the highly successfulWDM-2 and shares the same engine and horsepower rating withWDM-3A. It is considered^{[by whom?]} to be a successful locomotive class with high reliability and few maintenance problems. Despite the introduction of more modern types of locomotives likeWDG-4 and electrification, a significant number are still in use, both in mainline and departmental duties.

As of September 2023, 787 locomotives still retain "operational status" on the mainline as WDG-3A, with a few examples having been converted toWAGC-3 or WAG-10.

The first units of this class was delivered on July 18, 1995, under the name ofWDG-2.^[1] The class was manufactured till end of 2015. All the older locomotives built by DLW had regular WDM-2 type square short hood profile and control stand position and the locomotives are rated at 3,100 HP.

From 2009 onward, they are equipped with Daulat Ram DBR, microprocessor control and an Auxiliary Power Unit (APU) in the short hood thus they bear external resemblance to theWDM-3D class.^[2][3] The WDG-3A has higher Tractive Effort (7.5 t more) and Axle Load (1.7 t) compared to the WDM3A despite having the same engine and horsepower rating. Many units of this class has been named "Shakti" and can easily be recognized by their orange livery with cream stripe & lightning bolts. BesidesIR, WDG-3A are being use by private companies for industrial uses, thermal power plants, port trusts, etc.

Production was stopped in 2015 when advanced locomotives like theWDG-4D were built, thus rendering the ALCO platform obsolete. Two WDG-4s can haul more goods than three WDG-3A combined. Meanwhile, Diesel Loco Works in Varanasi rebuilt few of the existing locomotives that had reached midlife into a purely electric twin section 10,000 hp (7,457 kW) locomotive, classifying them as the WAGC3.

The retirement of this class has begun due to electrification.^{[citation needed]}

They were an experimental technical variant of the WDG3A with an upgraded ALCO engine to output 3,200 hp, though it was unsuccessful, and all units were reverted to normal WDG-3A. One of the locomotives of this class was numbered #14796.^[4]

Another experimental class, but this time rated at 3300 hp. Only one unit (#14962) was produced and was painted in a unique "Dark Rose/Cheetah" livery.^[5][6] This loco was derated to 2,600 hp, but is still with theKatni diesel locomotive shed. This class was unsuccessful as well.^{[citation needed]}

Freight version of theWDM-3D. Only one (#13301) unit was marked with this marking. It may possibly be rated at 3400 hp.^[7][8] Now^[when?] it has been derated to 2600 hp with WDG-3A class markings and homed at the Vatva Loco Shed.^{[citation needed]}

In 2018,Chittaranjan Locomotive Works,Banaras Locomotive Works andResearch Design and Standards Organisation converted a WDG-3A into a purely electric, twin-section 10,000 hp (7,457 kW) locomotive, classified as theWAGC3.^[10] This locomotive was the result of the initiative taken up by the Railway Board in November 2017, asking RDSO to work out details of conversion of diesel locos to electric locos. RDSO had suggested that such conversion would be possible with retaining the Motorized Truck assembly (which includes traction motors and drive side traction converters), computer controlled brakes (CCBs) and other relevant parts, suitably redesigning the under-frame and superstructure and adding the conversion kit. It was completed in only 69 days.^[11][12] Both units will together be considered as one asset and one locomotive by Indian Railways. Only a single unit has been produced so far^[when?] and it is in service. It has been given to Bondamumda Shed of SER.

Technical details are as follows:^[13][14]

• Indian locomotive class WDM-3A
• Indian locomotive class WDM-2
• List of diesel locomotives of India
• Indian Railways
• Rail transport in India