Jab rear panto ko use kiya jata hain normal ohe mein toh air ki resistance pantograph ko upar push karta hain .. jissey pantograph ko ohe sey contact rakhney mein help hoti hain ..
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But in case of high rise ohe system, air resistance pantograph ko neechey Push karta hain rear pantograph key case mein .. So ussey electric arc aur spark bahut hota hain kyuki proper contact nahi rehta high speed par..
WR...
more... aur RDSO key madad sey trials mein pta chlaa ki high rise ohe system mein front pantograph usually air resistance key wajah sey upar hi push karta hain ..jaisey normal height ohe system mein hota hain ..
So isiliye agar speed 80 kmph tak hi hain toh rear pantograph use kar saktein hain ..but passenger trains 110 pey chlti hain ..so unkey liye front pantograph ko upar rakna padta hain ..
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Also, rear pantograph limit : 80 kmph
Frony pantograph limit : 110 kmph ..