4. Rolling stock adapted to the type of operation

4.1 Main line: locomotive

This is the engine par excellence for towing all types of train: passenger or freight. Its dimensions range from 500 kW to 2,800 kW for autonomous traction, and 6,000 kW for electric traction. Depending on the type of route, the electric locomotive can be multi-voltage (up to four voltages in Europe). Its axle architecture is most frequently :

• 2 bogies with 2 driving axles or BoBo ;

• 2 bogies with 3 driving axles or CoCo ;

• some cases of 3-bogie locomotives...