In India, locomotives are classified according to their track gauge, motive power, the work they are suited for and their power or model number. The class name includes this information about the locomotive. It comprises 4 or 5 letters. The first letter denotes the track gauge. The second letter denotes their motive power (Diesel or Electric) and the third letter denotes the kind of traffic for which they are suited (goods, passenger, mixed or shunting).

Classification Syntaxes Edit


A Pune WDM3A Loco

The first letter (gauge)

The second letter (motive power)

  • D-Diesel
  • C-DC electric
  • A-AC electric
  • CA-Both DC and AC, 'CA' is considered a single letter
  • B-Battery Electric (rare)

The third letter (job type)

  • G-Goods
  • P-Passenger
  • M-Mixed; both goods and passenger
  • S-Shunters
  • U-Electric Multiple Units (used as commuters in city suburbs)
  • R-Railcars

For example, in "WDM3A":

  • "W" means Broad gauge
  • "D" means diesel motive power
  • "M" means suitable for mixed(for both goods and passenger)service
  • "3A" means the locomotive's power is 3100 hp ('3' stands for 3000 hp, 'A' denotes 100 hp more)

Or, in "WAP5":

  • "W" means broad gauge
  • "A" mean AC electric traction motive power
  • "P" means suitable for passenger service
  • "5" denotes that this loco is chronologically the fifth electric loco model for passenger service.

A WAP5 at New Delhi

See AlsoEdit