Why do locos sometimes use the rear pantograph and sometimes the front pantograph?

Latest News

1 Rail News

Shri Ram Karan Yadav takes over as General Manager, Central Railway

view all>>

2 Railway Employee

रेलवे का राजस्थान को एक और वंदेभारत एक्सप्रेस ट्रेन का तोहफा, जयपुर से इस दिन से चलेगी ये ट्रेन

view all>>

3 Always Important

जानिए पटरियों के साइड में क्यों लिखे होते हैं नंबर?

view all>>

Why do locos sometimes use the rear pantograph and sometimes the front pantograph?

July 16, 2019, 1:47 PM

There is in principle no difference between using the front and the rear pantographs for most locos as each is fully capable of delivering the required electric current from the catenary to the loco. (The AC-DC locos are special in that each loco is intended for a different traction supply.) Generally on IR there is no need for both pantographs to be raised at once since there are usually no unusual situations such as frost on the catenary or increased current collection requirements seen with other countries’ railways.

Yet, it is often seen that there are some definite patterns in pantograph usage. It has been the practice in many areas for locos to always have their rear pantographs up. It is thought that this practice arises from the idea that entanglement of the catenary by the front pantograph may result in damage to the rear pantograph as well as the debris or broken equipment lands on it, and using the rear pantograph lessens the chance of this. However, in recent years, this does not seem to have been adhered to very much. Another pattern that has been seen, especially in northern India, is for the front pantograph to be used extensively in the winter, but not in the warmer months. As a variation of this, it is also known that in certain divisions or zones, orders have been issued for drivers to use the rear pantographs at night. While the reasons for these usage patterns are not entirely clear, it is thought that there is a concern about condensation and the accumulation of dew on the catenary. An adequate technical explanation for the pantograph usage pattern is not known at this time [1/07]. (Please note – theories about falling water from dew on the catenary causing short circuits in loco equipment are implausible considering that locos operate just fine in heavy rain.) It has been suggested that front pantograph use may be a historical vestige from British practice carried over from conditions in the UK where sometimes the front pantograph was raised to scrape ice from the catenary and allow the rear pantograph to collect current fully, but this has not been substantiated either.

Railway Employee (App)

Rail News Center ( App)

Railway Question Bank ( App)

Railway Mutual Transfer

(App)

Information Center ( App)

Disclaimer: The Information /News /Video provided in this Platform has been collected from different sources. We Believe that “Knowledge Is Power” and our aim is to create general awareness among people and make them powerful through easily accessible Information. NOTE: We do not take any responsibility of authenticity of Information/News/Videos.

This entry was posted in 2 Railway Employee, STUDY NEW