Indian locomotive class WAM-4


The Indian locomotive class WAM-4 is a class of 25 kV AC electric locomotives that was developed in the 1970 by Chittaranjan Locomotive Works for Indian Railways. The model name stands for broad gauge, AC Current, Mixed traffic engine, 4th generation. They entered service in March 1971. A total of 500 WAM-4 were built at CLW between 1970 and 1983, which made them the most numerous class of mainline electric locomotive till its successor the WAG-5.
The WAM-4 is one of the most successful locomotives of Indian Railways having served both passenger and freight trains for over 50 years. This class provided the basic design for a number of other locomotives like WCAM-1, WAG-5A, WCG-2, and some WAP models. However, with the advent of new 3-phase locomotives like WAP-5 and WAP-7, the WAM-4 locomotives were relegated to hauling smaller passenger trains and now the aging fleet the WAM-4 locomotives are being rapidly scrapped and have been fully withdrawn from mainline duties.

History

The history of WAM-4 begins in early 1970s with the aim of addressing the shortcomings of the previous WAM-1/2 and WAG 1, WAG-2, WAG-3, WAG-4 classes and remove steam locomotives from IR by a target date of 1990. The WAM-1s were not great successes as some of their advanced features were unsuitable for Indian conditions.
so the designers at RDSO and CLW decided to use the following
Production of these locomotives started in 1970 with #20400 and exactly 500 WAM-4s were built in 13 years with #21399 “Anant” being the last one. Production ended on August 3, 1983.WAM-4 though an indigenously produced loco was heavily inspired by French box design and naturally favoured a French TM which was the Alstom made TAO TM. A single WAM-4 can generally haul up to a 24-coach passenger rake.This class proved so successful by virtue of its ruggedness suitable for Indian conditions and simplicity of maintenance. In January 2020, the last WAM-4 units were withdrawn from manline service. Currently 8 locomotive are currently doing shunting and departmental works.

Variants

This loco class has been seen in many variations, as a lot of workshops and sheds have carried out their own enhancements or modifications to the basic loco design. Although the code indicates a mixed-use loco, most WAM-4's ended up hauling passenger trains.
Variants include
The 'DB' or 'D' generally, but perhaps not always, indicates dual-brake capability. 'HS' may be for 'high speed'.'2S', '3P', '6P', etc. indicate traction motors connected in series or parallel. The WAM-4 has six traction motors, and originally they were wired to be available in different configurations at different power settings. At notches up to 14, all motors were in series ; up to notch 21 in series-parallel combinations ; and further notches with all motors in parallel. This is the original configuration of the WCAM-1 series of locomotives too.
The WAM-4 locomotives were later reconfigured to have all motors always in parallel or with the three series-connected pairs in parallel. Some WAM-4 locomotives from CLW are thought to have had the 2S 3P configuration right from the start. The 2S 3P configuration was better for the mixed traffic loads especially as it allowed the locomotives to start hauling larger loads without stalling. With increasing use of the WAM-4 locomotives for passenger traffic the all-parallel configuration was deemed more desirable since it allowed higher speeds and higher acceleration.

Livery

This loco has the widest variety of liveries, with each loco shed having its own livery
Most of the WAM-4 locomotives now have their MU capability disabled as RDSO disapproves of these locomotives running MU'd over 100 km/h.

Named locomotives

A few WAM-4 locomotives have been named by Indian Railways
ClassLoco NumberNameLoco ShedCurrent statusref
WAM-420401RajatabhaBhillai Condemned
WAM-420420Sukh Sagar NaveenVijayawada Scrapped
WAM-420615SurubhiAasansol Condemned in November 2011
WAM-421320GarudaArakkonam Plinthed at Rail Soudha, SWR HQ, Hubli
WAM-421380NavchetnaAsansol In Inferior service
WAM-421399AnantBhusawal The last WAM-4 ever built. No longer in holdings - assumed withdrawn/scrapped January 2019

Preserved Examples

A few WAM-4 locomotives have been preserved by Indian Railways at various location around India
ClassLoco NumberPrevious shedNameLIveryLocationref
WAM-420400BIABIA cream/orange with blue stripeUsed at Electric Loco Training Center, Uslapur . Reumbered ELTC-120
WAM-420472Ghaziabad Restricted to shunting/departmental duties only. Earmarked for preservation: I.R. Heritage Website
WAM-420484Bhusawal BSL cream/orange with orange liningLoco now preserved at CLW loco park
WAM-420601Jhansi Maroon with [cream bandEarmarked for preservation: I.R. Heritage Website
WAM-421320Arakkonam GarudaRed/dark grey/light grey with white linePlinthed at Rail Soudha, SWR HQ, Hubli
WAG-5/WAM-4B21101Tatanagar Brown/Black with Yellow stripePlinthed outside TATA

Locomotive sheds

Former sheds

Image Gallery