Many of the passengers who travel in trains are either not aware of what is a locomotive type or are confused by their types written in short form on it (like WDS 6) ?
The locomotives in Indian Railways can be broadly classified into 3 categories based on their gauge :
- Narrow Gauge Z or N.
- Meter Gauge Y.
- Broad Gauge W.
These can be further classified on the basis of their powers i.e. from where do they get or generate power :
Battery locomotives B.
These are then classified into 3 more sub categories based on their purpose or use :
- Locomotives used in only freight trains are referred as Goods G.
- Locomotives used in only passenger trains (all trains that carry passengers) are referred as Passenger P.
- Locomotives used in both the above tasks are referred as of Mixed type M.
- Locomotives used for shunting B.
The Type syntax :
The first letter (gauge)
- W – Indian Broad gauge (the “W” Stands for Wide Gauge) – 5 ft 6 in (1,676 mm)
- Y – metre gauge (the “Y” stands for Yard Gauge) – 3 ft 3 3⁄8 in (1,000 mm)
- Z – narrow gauge – 2 ft 6 in (762 mm)
- N – narrow gauge (toy gauge) – 2 ft (610 mm)
The second letter (motive power type)
- D – diesel
- C – DC (Direct Current) electric (can run under DC overhead line only)
- A – AC (Alternating Current) electric (can run under AC overhead line only)
- CA – both DC and AC (can run under both AC and DC overhead line); ‘CA’ is considered a single letter
- B – Battery electric locomotive (rare)
The third letter (job type or its use)
- G – goods
- P – passenger
- M – mixed; both goods and passenger
- S – shunting (also known as switching engines or switchers in the USA and some other countries)
- U – multiple units (EMU/DMU)
- R – Railcars.
The number after this is the locomotive generation number.
Now lets try on the type syntax “WDS 6”
W – Broad Gauge.
D – Diesel
S – Shunting.
6 – Locomotive generation.