130km/h (some documents suggest 140km/h). Some (5?) with Flexicoil Mark II bogies were classified WAP-1 FM II and later WAP-3. Two WAP-1 units were also converted to WAP-6. [10/02] One of them, #22212, the first prototype WAP-6, was then converted to a WAP-4 and was based at Jhansi (now [8/03] at Mughalsarai).
Many remaining WAP-1's are being converted to WAP-4's by a complete retrofit including new traction motors, new transformers, etc. These upgrades do not result in the 'R' suffix in the road number that is typical for rebuilt locos. Ghaziabad shed locos are currently [1/05] the only ones not scheduled for such upgrades and are expected to remain as 'pure' WAP-1 units. The WAP-1E has only air brakes. Earlier WAP-1's had loco air brakes and vacuum train brakes but were retrofitted for dual train brakes. Motors are grouped in 2S-3P combination and weak field operation is available. Elgi compressors, Northey exhausters, S F India blowers. The locos were originally not designed for MU operation but were later modified to allow MU'ing.
Manufacturers: CLW
Traction Motors: Alstom/CLW - TAO 659 (575kW (770hp), 750V, 1095 rpm) Axle-hung, nose-suspended, force-ventilated.
Gear Ratio: 58:21
Transformer: BHEL type HETT-3900, 3900 kVA. 32 taps.
Rectifiers: Two silicon rectifiers, with S18FN35 cells (by Hind Rectifier) with 64 cells per unit. 2700A/1050V.
Axle load: 18.8t.
Bogies: Co-Co Flexicoil (cast steel bogies); primary and secondary wheel springs with bolsters
Pantographs: Two Faiveley AM-12.
Current Ratings: 900A/10min
Details of WAP-4:
Variant of WAP-1 with Hitachi H5 15250 motors (built by CLW), built in 1994 to RDSO specifications. The need to run longer passenger trains (24 to 26 coaches as against the 19-coach capacity of the WAP-1 / WAP-3 locos), and also to eliminate the need for bankers in graded sections (e.g., the busy Itarsi-Nagpur section) led RDSO to consider an upgraded design of the WAP-1 loco and the WAP-4 loco design was published in November 1993. Indigenously designed, higher power rated silicon rectifiers and indigenously-designed 5400kVA transformer. Locomotive reliability is also increased by the use of Hitachi traction motors. Air brakes for loco and train. Different underframe design to handle larger buffing loads. Cast bogie, Flexicoil Mark 1 design. Weight kept to 112t by the use of aluminium plates, thinner underframe, and reducing some components such as sanders. Motors grouped in 6P combination; weak field operation possible.
[2/00] New versions of these with twin-beam headlights, speed recorders and some changes to the control electronics have been rolling out recently [7/00]. WAP-4E are most likely just regular WAP-4 locos from the Vadodara shed. The 'E' suffix is thought to come from the short-lived RDSO directive to denote all air-braked locos and is redundant with the WAP-4 locos (e.g., WAP-1E). WAP-4There is speculation that some of these locomotives may have some additional features such as an electronic sensor for detecting loss of pressure in brake pipes (hence, sometimes the 'E' suffix is explained as 'electronic', although this seems unlikely). More recently [1/05] many of these have been fitted with train-parting / pressure loss alarms, and data recorders for speed, energy consumption, etc. All the new ones have roof mounted twin beam headlights, square WAP-5 type windscreens and a digital notch repeater along with a better layout and good seats for the drivers. Some [12/04] even have windshield washers. A few were provided with signalling lamps on the sides but this does not have seem to have continued with the newer units.
WAP-4[1/03] Although these are officially rated at 140km/h, there are reports that one or more of these have been tested by CLW at up to 169.5km/h.
As of [11/04] this class is still in production at CLW.
Note on the traction motors : The Alstom-designed 770hp TAO motors used in the WAP-1 and WAP-3 were seen as the weak link in the reliability of the locos for passenger train use. At the time, Hitachi motors of 840hp were in use on freight locos and had very high reliability, but adapting them for use with a passenger loco proved a formidable challenge because of the weight constraints. The WAP-4 design efforts involved many modifications for weight reduction, including a lighter underframe, aluminium foil-wound transformer, and the use of aluminium chequered plates, and these have allowed the use of the heavier, but more powerful and more reliable Hitachi motors on the WAP-4 locos.
Manufacturers: CLW
Traction Motors: Hitachi HS15250 (630kW, 750V, 900A. 895rpm. Weight 3500kg). Axle-hung, nose-suspended, force ventilated, taper roller bearings.
Gear Ratio: 23:58 (One loco, #22559, is said to have a 23:59 ratio.)
Transformer: 5400kVA, 32 taps
Rectifiers: Two silicon rectifiers, (ratings?).
Axle load: 18.8t.
Bogies: Co-Co Flexicoil Mark 1 cast bogies; primary and secondary wheel springs with bolsters
Pantographs: Two Stone India (Calcutta) AM-12.
Current Ratings: 1000A/10min, 900A continuous
Tractive Effort: 30.8t
A 24-coach (1430t) passenger rake can be accelerated to 110km/h in 338 seconds (over 6.9km) by a WAP-4; to 120km/h in 455 sec. (10.5km); and to 130km/h in 741 sec. (20.5km).
Link of this Info:
click hereAttached Image: SRC WAP-4 in charge of 12022 BBS HWH Janshatabdi
Courtesy: Anindya Roy
SRC WAP-4 22253 
