The term DBR stands for Dynamic Brake Resistors.It is installed on the Roof of the Locomotive so it is called "Roof Mounted" which means installed on the Roof of the Locomotive.
To know the Function and Advantages of Roof Mounted DBR please click on the following link:
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For learning purpose please see the edited attached image of SRC WAP-4 22839 clicked by...
more... me on 17.05.2015 at PF No 5 of PURI Station before my return journey by 12278 DN Puri HWH Shatabdi Exp.
You can see the Roof Mounted DYNAMIC BRAKE RESISTORS of the Loco in the Picture.
To know the concept of Dynamic Braking please refer:
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