Indian locomotive class WAP-4

Specifications
Specifications
Configuration:;
• AAR	C-C
• UIC	Co'-Co'
Gauge	5 ft 6 in (1,676 mm)
Bogies	Co-Co Flexicoil Mark 90 cast bogies; primary and secondary wheel springs with bolsters
Wheel diameter	New: 1,092 mm (3 ft 7 in); Half worn: 1,055 mm (3 ft 5+1⁄2 in); Full worn: 1,016 mm (3 ft 4 in)
Length	18.794 m (61 ft 7+29⁄32 in)
Width	3.179 m (10 ft 5+5⁄32 in)
Height	4.272 m (14 ft 3⁄16 in)
Axle load	18,800 kg (41,400 lb)
Loco weight	116,000 kg (256,000 lb)
Electric system/s	25 kV 50 Hz AC Overhead
Current pickup(s)	Pantograph
Traction motors	Hitachi HS15250
Loco brake	Air
Train brakes	Air
Safety systems	Slip control, Over voltage relay, Main overload relay, Earth Fault Relay, Low Pressure Governor, Brake Cylinder Cutoff Valve, Train parting alarms and No OHE volt relay

Type and origin
Type and origin
Power type	Electric
Builder	Chittaranjan Locomotive Works, West Bengal, India
Build date	1993 till 2 December 2015
Total produced	778 as of August 2016 (Production ceased)

WAP-4
WAP-4
	Erode based WAP-4 at Madgaon Jn.
Power type
Type and origin
Power type	Electric
Builder	Chittaranjan Locomotive Works, West Bengal, India
Build date	1993 till 2 December 2015
Total produced	778 as of August 2016 (Production ceased)
Configuration:;
Specifications
Configuration:;
• AAR	C-C
• UIC	Co'-Co'
Gauge	5 ft 6 in (1,676 mm)
Bogies	Co-Co Flexicoil Mark 90 cast bogies; primary and secondary wheel springs with bolsters
Wheel diameter	New: 1,092 mm (3 ft 7 in); Half worn: 1,055 mm (3 ft 5+1⁄2 in); Full worn: 1,016 mm (3 ft 4 in)
Length	18.794 m (61 ft 7+29⁄32 in)
Width	3.179 m (10 ft 5+5⁄32 in)
Height	4.272 m (14 ft 3⁄16 in)
Axle load	18,800 kg (41,400 lb)
Loco weight	116,000 kg (256,000 lb)
Electric system/s	25 kV 50 Hz AC Overhead
Current pickup(s)	Pantograph
Traction motors	Hitachi HS15250
Loco brake	Air
Train brakes	Air
Safety systems	Slip control, Over voltage relay, Main overload relay, Earth Fault Relay, Low Pressure Governor, Brake Cylinder Cutoff Valve, Train parting alarms and No OHE volt relay
Maximum speed
Performance figures
Maximum speed	140 km/h (87 mph)
Power output:;
• Continuous	5,050 hp (3,766 kW)
Tractive effort:;
• Starting	30,800 kgf (302 kN; 68,000 lbf)
Operators
Career
Operators	Indian Railways
Numbers	22061 and from 22201-22399, 22500-22999 & 25000-25051
Locale	All over India
Disposition	Active

The Indian locomotive class WAP-4 is a class of 25 kV AC electric locomotives that was developed in 1993 by Chittaranjan Locomotive Works for Indian Railways. The model name stands for broad gauge (W), AC Current (A), Passenger traffic (P) locomotive, 4th generation (4). They entered service in late 1994. A total of 778 WAP-4 were built at CLW between 1993 and 2015, which made them the most numerous class of mainline electric passenger locomotive until the WAP-7.

The WAP-4 is one of the most successful locomotives of Indian Railways^{[peacock prose]} serving passenger trains for over 29 years. This class provided the basic design for other locomotives like the WAP-6. Despite the introduction of more modern types of locomotives like WAP-7, a significant number are still in use, both in mainline duties. Production of this class was halted in December 2015 with locomotive number 25051 being the last unit to be rolled out.

As of September 2022, all locomotives except those lost in accidents still retain "operational status" on the mainline as WAP-4, with further examples having been converted from WAP-6.