Answer / rajeshsan

Brushes with metal will lead arc and more wear & tear, Hence for large rating we will use carbon brushes. And for toy motor and very small motor use metal brushes.

Answer / mohanavel.u ,marg ltd

The carbon brushes are having the self lubricating capacity
and if metal is used it will lead to more wear and tear
produces spark and damage the armature.

Answer / pavan msh

brushes used in dc machines are mostly made of carbon bcz carbon is of low cost and also a good conductor

why transformer rating in kva?

7 Answers  

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Pleasd Tell Me..... In Generating Stations Why The Generation Of ELECTRICITY Is In 3 Phase Form?? OR In Generating Station Why We Generates The ELECTRICITY In The 3 Phase?? Why Not In The 4 Phase, 5 Phase Or 6 Phase Form??

3 Answers  

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what is meant by oil filled power & distrubution transformer ? if anybody know the link of detail about above transformers means plz send it i have interview on this week ? plz help me

3 Answers  

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what is direct dischage of power transformer

1 Answers  

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What is meant by rotor?

0 Answers  

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How to calculate cable size between battery charger to Battery ?

2 Answers   L&T,

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What is the limitation of kirchoffs law?

0 Answers  

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Which is remain unchanged in transformer action?

6 Answers   NTPC,

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Why collecting electrode of ESP to be earthed

0 Answers   NBVL,

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Why 1/3 is used in symmetrical components?

0 Answers   ABB,

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Lt motor sfu flashing reasons?

0 Answers   NDFL,

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Wat is the best to use in a generator a 6.5kva or a 7 kw

4 Answers  

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