The Indian locomotive class WCAM-1 was a class of dual-voltage (25 kV AC and 1.5 kV DC) electric locomotives that was developed in 1973 by Chittaranjan Locomotive Works for Indian Railways. The model name stands for broad gauge (W), DC Current (C), AC Current (A), Mixed traffic (M) locomotive, 1st generation (1). They entered service in March 1973. A total of 53 WCAM-1 were built at CLW between 1973 and 1979, which made them the most numerous class of mainline dual-power AC/DC electric locomotive.
The WCAM-1 was one of the most successful locomotives of Indian Railways, having served both passenger and freight trains for over 40 years between 1973 and 2015. This class was a bi-current version of the WAM-4 class. However, with the advent of new 3-phase locomotives like WAP-5 and WAP-7, the aging fleet of WCAM-1 locomotives were relegated to hauling smaller passenger trains and have been fully withdrawn from mainline duties. All units have been scrapped with no locomotives preserved.However, WCAM-1 #21817, which was renumbered as #21800, was originally going to be preserved at Valsad Electric Loco Shed, but however, it got scrapped instead.
History
The WCAM-1 was a class of locomotive used in the Indian Railways system. They were the first locomotives from the WCAM class. These locos were operational in routes around Mumbai. These locomotives worked on both AC as well as DC as their classification suggested. They hauled trains from DC section of suburban railway to AC section and thus performed a very critical task as they could easily operate on both AC and DC. However they performed poorly in DC mode compared to AC mode but they were very robust and had easy operating and handling characteristics.
These were 1st class of Wide Gauge's (W) Bi-current charged (CA - runs both under AC and DC) and Mixed load series (M - hauls both passenger and freight trains). These were the first electric locomotives to enter Western Railway's Mumbai division; prior to that steam and diesel locomotives used to haul trains in Western Railway's Mumbai division. These brought an end to the steam era in this division. They were also the first locomotives allotted to Valsad (BL) shed. Their top speed under DC was the lowest, as compared to other Bi-current charged locomotives. They were the first Bi-current charged locomotives in the country. Initially all were vacuum braked but were retrofitted with air brakes to make them dual braked. Some also had their vacuum brakes replaced with air brakes. Introduced in 1975. One of the single pantographs on the WCAM-1 is used in DC traction; the other one carries AC current. The two pantographs were not identical, though similar in design. Originally built with vacuum brakes only, although a few (Nos. 21805, 21807, 21812, 21828, 21838, 21844, 21845, and 21850) had both vacuum and air brakes. They lacked dynamic brakes. The WCAM-1 did not use a variable ratio auto-transformer in AC mode like the others; it used a fixed-ratio transformer and rectifier bank to convert the OHE supply to 1500 V DC. The design of the transformers and notches made this a hard machine to operate, with the fusible links tending to blow often. Of the 28 notches, notches 4, 14, 21, and 28 were used for continuous operation, although notch 4 was intended for low-speed shunting and was very ineffective. Notches 14, 21, and 28 were the terminal notches of the series, series-parallel, and parallel circuit notch sequences. In DC mode, the WCAM-1 used resistor banks for speed control. However they were very robust machines and relatively easy in the handling characteristics. WCAM-1's had three traction modes (series, series-parallel, parallel) in both DC and AC mode, but using the parallel mode in DC was discouraged because of power problems. In practice this was not restrictive since series-parallel notches allowed reaching 75 km/h or so. In AC mode, the locos were almost always used with the motors in all-parallel mode. Unlike the WCAM-2 and WCAM-3 locos, no reconfiguration has been carried out to force the use of all-parallel mode with AC. Weak field operation was available. They were briefly tried out for freight use by CR, but all finally ended up with WR. The top ones getting the WCAM-2P (see below). [5/02] However, CR's Indore-Pune weekly train had been hauled by a WR WCAM-1. Max. speed 100 km/h, 110 km/h after regearing. Traction motors were nose-suspended and axle-hung.
Also during 1992-1996, the WCAM-1 was occasionally used on express trains on the Bombay division of Central Railway (along with WCG-2 and WDM-2) due to the aging failure of WCM locomotives. When WCAM-3 entered service in 1997, the WCAM-1 was brought back to Western Railway, while WCG-2 was transferred back to freight duties over CR Bombay division and WDM-2 was transferred to Konkan Railway duties.
Then, the WCAM-1 continued duties over the Mumbai–Ahmedabad line of the Western Railway for another 15-18 years. After the entire Western line section was converted to AC traction on 5 February 2012, those locos were aging, meaning they would've ended their coal life. The first unit of this class, #21800, was withdrawn from service on 10 April 2012, while the last one, #21852, was withdrawn from service on 11 May 2015. Since then, all units of this class have been scrapped with no locomotives preserved.
Technical specifications
Source:
Of all the 30 notches, 1-21 were DC notches allowing series operation of traction motors. Rest of the 8 notches allow series-parallel combination under DC. Under AC, the combinations were 3S-2P and 2S-3P. These locomotives could run in parallel combination but it was discouraged due to power problems under DC. Under AC, the locomotives were run under parallel notches nearly always. Although these engines were not rebuilt to use only parallel combination under AC. Field weakening of traction motors was possible at 21st and 30th notches. Voltage control was done by Tap changer operation under AC and Resistance notching under DC. Traction motors were charged by DC. Its prototypes were tested in the year 1971.
Traction MotorsAlstom/CLW TAO 659 A1 . Axle-hung, nose-suspended and force ventilated. Temperature rise by resistance in Armature - /Field - . Coil resistance at in Armature - 0.0151 ohms/Main pole - 0.0145 ohms/Interpole - 0.0078 ohms. Starting current - 1100 A. 1 hour rating - , 750 V, 870 A and 1070 RPM. Continuous rating - , 550 V, 840 A and 1095 RPM. Air gap in main pole - /Interpole - . Grade of brushes - EG 367, 6 brush holders and 3 brush per holderGear Ratio61:16, 58:21TransformerBHEL made BOT 34600. , Forced Oil cooling, Class 'A' insulation and 32 taps. Primary rating - 3646 kVA, 22.5 kV and 162 A. Secondary rating - 3460 kVA, 1730 V (DC) and 2x1000 A (DC). Tertiary rating - 274 kVA, 1470 V and 186 ASilicon Rectifiers48 cells (321 UFR200) per bridge. Continuous rating - 1000 A each cubicle. 1 hour rating - 1270 V. Max starting current - 1650 A. Forced air cooling.PantographsFaiveley AM-12 (AC) and Faiveley AM-18B (DC)Bogie Drive ArrangementGear pinionAuxiliaries2 Headlights (750 W and 32 V). Lead Acid battery (50 cells), Rating - 110 V and 5 hours.Motor-Alternator SetSOA-749 Alternator by Kirloskar Group (180 kVA, 400 V, 270 A, 1500 RPM and 3 phase). AY100AZ Motor by AEI (, 1500 RPM, 1400 V and 136 A continuous).Number of sand boxes16Main Starting Resistance blowerFour PETA-60 types by SF Product (). ILA2-116.2 type Motor by Siemens(, 400 V, 18 A and 2925 RPM).Auxiliary RectifierRating with 2 bridges in parallel - 180 A (Continuous) and 1000 A (5 seconds)/1 bridge - 90 A (Continuous), 140 A (30 minutes) and 900 A (2 seconds). Natural Air cooling. Twenty four 324-UFR200 type cells connected by bridges.2EC388 type Compressor by KirloskarRating - at . Motor - , 38 V, 15 A and 1390 RPM.2 Exhausters by Gresham and CravenNorthey-250RE type. Two 385 V motors.2 Traction Motor Blowers by SF ProductMLBRX-42.5-1-H4 type (). 2 Motors by Siemens(, 385 V, 41 A and 3000 RPM).PFTA-50 Arr 6 type Smoothing Reaction Blower by SF ProductCapacity - . Motor - , 380 V and 2860 RPMMLBR-60-1-H2 type Oil Cooler Blower by SF ProductCapacity - . Motor - , 380 V, 43 A and 1470 RPM2 Silicon Rectifier Blowers by SF ProductPHMX-40-6 type (). 2 Motors - , 380 V, 4.4 A and 2860 RPM.Oil Pump by Best and Company Private LimitedCapacity - Motor - , 380 V, 66 A and 2865 RPMSL-42 type Smoothing ReactorRating - 1250 V and 950 A. 0.00718 ohms resistance at .NotchesTotal 30
Locomotive shed
All 53 WCAM-1s were based at Valsad Electric Loco Shed in Gujarat, and were withdrawn from service after the conversion of entire Mumbai region into AC traction.
Trains Hauled by WCAM-1
The WCAM-1 were employed on all express trains, including Shatabdi and Rajdhani Express (till Vadodara), until AC electrification of Mumbai area. The arrival of WCAM-2P engines did not reduce their work loads. Later on, with introduction of more modern AC locomotives and need for faster trains, the WCAM-1s were relegated to secondary passenger trains, including: Mumbai Central - Ahmedabad Junction Passenger Valsad - Bandra Terminus express Valsad - Viramgam Passenger Bharuch - Virar Passenger Valsad Fast Passenger Bandra Terminus Vapi Passenger Ahmedabad Passenger Surat - Virar Shuttle Ahmedabad - Valsad Passenger These trains were being hauled by the WCAM-1 locomotives, before their final retirement in 2015.
Performance
Source:
Following is the capacity of WCAM-1 locomotive with gear ratio 16:61 under AC for 4 wheeler wagons (in tonnes) :- Grade\km/h Start 20 30 40 50 60 70 80 Level 6000+ 6000+ 6000+ 6000+ 6000+ 5950 4530 3380 1 in 500 6000+ 6000+ 5850 4880 3640 3325 2675 2100 1 in 200 2900 2900 2900 2735 2100 1970 1630 1310 1 in 150 2250 2250 2250 2185 1690 1595 1330 1080 1 in 100 1535 1535 1535 1535 1195 1145 960 780 1 in 50 965 925 915 795 610 - - -
Following is the capacity of WCAM-1 locomotive with a gear ratio of 16:61 under AC for BOX wagons (in tonnes):- Grade\km/h Start 20 30 40 50 60 70 80 Level 6000+ 6000+ 6000+ 6000+ 6000+ 6000+ 6000+ 5675 1 in 500 4300 4300 4300 4300 4300 4160 3460 2820 1 in 200 2975 2975 2975 2975 2340 2245 1900 1570 1 in 150 2530 2530 2530 2360 1845 1775 1505 1250 1 in 100 1945 1910 1880 1635 1275 1235 1050 870 1 in 50 1120 950 940 815 630 615 - -
Following is the capacity of WCAM-1 locomotive with gear ratio 16:61 under AC for ICF coaches (in tonnes):- Grade\km/h Start 20 30 40 50 60 70 80 90 100 110 120 Level 1500+ 1500+ 1500+ 1500+ 1500+ 1500+ 1500+ 1500+ 1500+ 1500+ 1500+ 1340 1 in 500 1500+ 1500+ 1500+ 1500+ 1500+ 1500+ 1500+ 1500+ 1500+ 1500+ 1200 885 1 in 200 1500+ 1500+ 1500+ 1500+ 1500+ 1500+ 1500+ 1445 1175 995 760 565 1 in 150 1500+ 1500+ 1500+ 1500+ 1500+ 1500+ 1400 1175 960 815 625 465 1 in 100 1500+ 1500+ 1500+ 1500+ 1295 1175 995 840 690 590 450 330 1 in 50 1165 970 955 840 655 595 505 435 345 290 215 145
Following is the capacity of WCAM-1 locomotive with a gear ratio of 16:61 under AC for BOXN wagons (in tonnes):- Grade\km/h Start 20 30 40 50 60 70 80 Level 6000+ 6000+ 6000+ 6000+ 6000+ 6000+ 6000+ 6000+ 1 in 500 5015 5015 5015 5015 4900 4340 3600 2980 1 in 200 3305 3305 3305 3225 2530 2295 1945 1645 1 in 150 2770 2770 2770 2515 1980 1805 1535 1300 1 in 100 2085 1990 1960 1730 1365 1250 1070 905 1 in 50 1165 980 975 860 670 615 525 440
Following is the capacity of WCAM-1 locomotive with gear ratio 16:61 under DC for 4 wheeler wagons (in tonnes):- Grade\km/h Start 20 30 40 50 60 70 80 Level 6000+ 6000+ 6000+ 6000+ 6000+ 4300 2800 1815 1 in 500 4710 4710 4710 4710 3640 2390 1635 1110 1 in 200 2470 2470 2470 2470 2100 1400 980 675 1 in 150 1900 1900 1900 1900 1690 1125 790 545 1 in 100 1390 1390 1390 1390 1195 800 555 - 1 in 50 875 875 875 875 610 - - -
Following is the capacity of WCAM-1 locomotive fitted with TAO659A1 with a gear ratio of 16:61 under DC for BOX wagons (in tonnes):-