Why we can't start a tube light without a starter(choke) and an inductor?

1 Answers  

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why do we not use equivalent voltage source in negative sequence equivalent ckt.

0 Answers   TATA,

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What id difference between power and energy?

0 Answers  

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1.what type of wave is produced from i.online ups ii.offline ups iii.inverter.why don't we use inverter instant of offline ups for computer,what's the reason?

2 Answers  

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what condition there autotransformer will fail?

2 Answers  

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Is voltage & potential transformer are the same? Are they used for same application ?

11 Answers  

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I have a one P.F meter in my factory showing 2 phase leading and one phase lagging then what is my actual P.F.

1 Answers  

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explain 100 percent and 95 percent earth faults

1 Answers  

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Why are transmission lines multiples of 11? Is it because of some historic reason ? Or is there a scientific base to it?

5 Answers  

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What is meant by vector group

0 Answers   GPSC Gujarat Public Service Commission, VA Tech Wabag,

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Why do we give DC excitation to AC Synchronous motor??

9 Answers   Lance, MBM, Polycab,

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Any one can explain if there is any harm from humming noise heard from air circuit breaker : we have 415 switch board having two incomers from transformers 3.3KV/415V , when bus coupler closed, and open one ACB incomer to work in one of the transformers, the current started hunting around 50 Amps, and heard humming noise from the air circuit breaker, although the load current was only 1200 amps while the ACB capacity is 2500 Amps, and the transformer 1600 KVA. The same didn't happen when taken the other transformer offline. Why this humming noise and current fluctuation? is there any implication or danger, bearing in mind that we just returned everything back to normal and stopped the maintenance of the transformer. Shall we go ahead and ignore this noise?

6 Answers  

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