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

Differentiate between power relay and reverse power relay?

2 Answers   ABB, TVS,

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13 Answers   HAL, TATA,

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1 Answers  

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why are u join ntpc

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ple send to the how to improve the efficiency & economical to the thermal power plant

1 Answers  

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what happens to current , when voltage drops .?

11 Answers  

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14 Answers   ABB, L&T,

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1 Answers  

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0 Answers   Harshal Electrical,

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Does the motor power displayed on the Motor name plate is the mechnical power motor delivers or it is consumed power from the system?

2 Answers  

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