In an alternator running with a balanced zero p.f. lagging load, phase differernc between the resultant armature flux and main field flux is always____? options is 180 degree....why?? explain.

1 Answers   BREB,

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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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how do you reduce the skin effect

2 Answers  

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why rating of generator is kva but motor is kw ?

4 Answers  

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how can we test the vector group of transformer

1 Answers  

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How can i get my certificate of competency as an electrical supervisor? I have complicated my B.Tech from Uttarakhand technical university this year (2012).

0 Answers   ONGC,

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how can i find ct ratio of meter by seeing name plate of meter and how it should be used in MF calculation if it shows only-/1???

0 Answers   Harshal Electrical,

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When do you use a VFD motor?

3 Answers  

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In Transmission System if the potential difference at the two end of line are same then is the transmission of power will continue ? if yes then how.

1 Answers   IOCL,

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we are having 15kw and 3kw motor both can run in same time , instead of using copper we are using ug aluminium cable , 35 sq.mm is suitable for its current carrying capacity..?

0 Answers   Afflatus Grauver Pvt Ltd,

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how much value of resistance should connect to 15 kw, 6 pole 3 phase slip ring induction motor having RV-240, RA-42.

0 Answers  

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Control wiring of a dol starter for forward and backward

0 Answers   Basj Industries,

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