Why the brushes used in dc machines are made of carbon not from other metal?

3 Answers  

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what happens when d cexcitation given to alternator is removed while it is running or what happens when dc excitation is failed in alternator while running?

10 Answers  

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Why have to use copper cable for local isolator to motor ?

0 Answers  

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To measure insulation resistance of 11KV cable between core & armour, what should be the test voltage & duration?

4 Answers  

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howmany types of compresor is there? and how to calculate compresor capacity?

3 Answers  

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What is technical difference between ELCB & ELMCB?

3 Answers  

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what is difference between earth fault& restricted earth fault.

3 Answers  

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Trafo ratio is 11kV/6.6kv,Vector group is YND11. What will be the effect if secondary is used for earthed system.

0 Answers  

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hi can you give any body fault level calculation, generator fault level calculation,transformer fault level calculation for system fault level with equation? i have 3.3kv generation voltage three gas gen sets, one is 1.9MW,2nd is 2.5MW,& 3rd is 3.8MW & i have 11 kv generation voltage one gas gen sets is 3.8MW, we are step up to 22kv by transformer

3 Answers   Hindalco, Piramal Healthcare,

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what happen for input voltage output voltage input current output current and kva if we increase primery winding in transformer?

1 Answers  

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What is Biased Generator Differential Relay?

2 Answers  

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explain the mode of metal iranafer in Co,welding

0 Answers  

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