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#FAQ
Why Locos run with front pantograph up during winter, foggy conditions or heavy rainfall?
Answer-- It is because of the dew during winter season. The extreme cold weather conditions cause the formation of dew which might affect the working of the servo motor which is connected to the small air tanks,which lifts the pantograph. The cool dew or even frost sometimes might jam the motor and affect the working of pantograph. If the rear pantograph is used during winter, the dew from the catenary(OHE) falls over the servo motor and affects...
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its working thus affecting the lifting of pantograph. In the case of front pantograph, dew does not fall on the servo motor while loco is in motion.
The servo motor controls the air pressure in the small air pressure tanks located just below the pantograph(as seen in the picture); Thus indirectly it controls the pantograph movement.
Thus for hassle free working of servo motors of pantograph, front one is used during the foggy weather in winter season.
Pictures are for representational purpose only. Second pic shows the servo motors of the pantograph.
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