TKD WDP-4B "प्रतीक" - रंग ऐसा कि हर किसी को प्यार हो जाए - Anubhav Kashyap

A Locomotive that is used to help the main locomotive of train on sections like hill or mountains .In those sections more tractive effort is required. These locos assist in hauling a train up a steep gradient.
There are Three Locations of Banker loco can be attached.
1)At the front OR/AND 2)Mid-train OR/AND 3)End of the train
Another reason banker loco...
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attached is to protect the train from a possibility of de-coupling of rake and consequent parting which would cause a portion of the train to hurtle backwards because of the gradient.
While descending a grade, bankers may be attached at the front for extra brake power.
This formation of locos is controlled by radio signals. If radio operation is not possible, electrical control may be used, .
Ex. of such sections where banker locos are attached.
1)Karjat towards Lonavala in Western Ghats.
2)Kasara towards Igatpuri in Western Ghats.