in our 6.6kv motor feeder[it is having two sources from Bus A&B] earth fault relay is acting, we checked CBCT connection and cable meggerd values found very good still earth fault acting during first two are three start after that it will hold. please clarify what was the reason. if same motor is starting from other Bus-A it will start.

1 Answers   Gasal, Voltech,

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what is meant by insulation voltage in cables? explain it?

4 Answers   ABB,

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how mass curve differs from hydrograph.

0 Answers  

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what will be efficient rating of ac motor to lift a 10 kg wt of stone to 10 meter height with input 220V AC 50 Hz frequency???

1 Answers  

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In case of a synchronous generator carbon brushes, some brushes expire before the others. Why is so? When all the brushes are installed at the same time, why don't thee expire at the same time?

1 Answers  

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How to decide DO set rating of Transformer?

0 Answers  

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what is the difference between multimeter and megger?

3 Answers   Bhel, Metro,

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Can transformer develop three phase power from a single phase source?

12 Answers   ONGC,

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what is the use of sdf?

0 Answers   Areva, SWAN,

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As per the theory current doesn’t flows in Neutral, but practically it is not applicable, explain why?

2 Answers  

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What are the causes of unbalanced current on 34.5kv feeder Ia=0.05,Ib= 0.25, Ic=0.15 and In=0.27 prior to tripping current are balance?

0 Answers  

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what is derated current of power cable & what is formule to find derated current?

1 Answers   Thermon,

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