Answer / subhashree

yes

Answer / ashish jani

do not use like 3 core cable due to dc supply only +v & -v

when we are going to higher voltage level in substations why we are using Sf6 circuit breakers instead of Vacuum circuit breakers.

3 Answers  

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An 11kv system consisting of an underground cable to a sub station about 300 meters away was shut down for about 10 hrs. On energising, it tripped off on earth fault about 10---20 mins later 6 times but since than it is not tripping.its already 3 weeks now. The SPAJ was found to be fine. what could be the cause.No test had been done to determine the cause of the trippings till now because of demand.

2 Answers  

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my bachelors was done with EEE now i got admit in NU with CS as course. how to answer this qns 1) why u choose cs? 2) why u changed from eee to cs

1 Answers  

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what will be the breaking capacity of MCCB of 1000kVA (6% Impedence) transformer? Voltage being 415V, Power Factor 0.8.

2 Answers   BPC,

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why always out of the 3 phase(RYB) of supply, in Y phase w.r.t the voltage is higher? on R & B phase the voltage will be lower as compared to Y phase?

1 Answers  

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in alternator what is use of AVR ? how AVR is operating either AC or DC?

1 Answers  

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what is purpose of using reactor in substations

4 Answers   NCC,

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If NO contact of relay gets supply from other sources or other part of circuit and at a time relay coil activates,then current will flow in which direction & will it cause to damage relay??

1 Answers  

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what is the difference between linear choke and suction choke?

1 Answers   BARC,

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what are the advantages and disadvantages of speed control of 3 phase induction motor by varying frequency explain with drawing

1 Answers   ABB, Genpect,

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what is under coal gassification?

1 Answers  

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How to calculate battery back up time for a 400 AH battery bank installed in telecom shelter for a load of 20 Amps and time taken to fully charge this battery bank?

3 Answers  

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