Answer / asmita

For calculation of efficiency of a T/F it is essential to
carry out Open Ckt. n Short Ckt test( As we can not load
each n every t/f to its rated capacity this will consume a
lot of power.)From O.C.test we can find iron losses of T/F
& from S/c test we can find full load or at any load copper
losses.
For these Electrodynamometer type wattmeters should be used
as it is very sensitive device n Power factor during this
test is very low.

Hi,Any one has idea regarding the KPTCL Recuirtments for AE'e & JE's for the year of 2009-10???Kindly help in regards..

2 Answers  

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Is a induction motor rotate by back emf ? If not , then how it is rotate ?

1 Answers  

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tell me working of air circuit braker.

2 Answers  

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A 100 kVA , 400 v/250 kv testing transformer has 8% leakage reactance and resistance on 100 KVA base . A cable has to be tested at 500 kv using the above transformer as a resonant transformer at 50 hz . if the charging current of the cable at 500 kv is 0.4 A find the series inductance required . Assume 2% resistance for the inductor to be used and the connecting leads . Neglect dielectric loss of hte cable . what will be the input voltage to the transformer ?

0 Answers   L&T,

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any application of back emf

0 Answers   MahaGenco,

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why battery room in substation is black coloured?

4 Answers  

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wat do knw aboot circuit breakers ?

9 Answers   IOCL,

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what is level 2 automation?

0 Answers  

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Dear Sirs, I am a technical persons.In one of our Electrical Sub- Station, We have installed three numbers of 1250KVA ,11KV/0.415KV Transformer to feed the Factory load. We have found some abnormality. In one of our Transformers the leakeage current from transformer body to earth through earth continuity wire is almost 86 Amp but in other transformer it is (5-10)Amp. where the load current on three phase and neutral are respectively 1360Amp,1400Amp,1370 Amp & 176Amp. So please any technical person help me about the reasons of this situation and how I can rectify the fault. Moreover,I have measured the earth resistance of the Earth continuity wire which is less than 1 Ohm. Thanks Tapas Barua

3 Answers  

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Why the capacitor bank is keeping on for electricity supply and keeping it off for generator supply

3 Answers  

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Can anyone explain how the vector diagram of a transformer which doesn't have name plate be found whether it is Dy11/Dy5/Yd11 and so on?

4 Answers   TATA,

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wat is the current produced in a 5000v megger? when the positive and negetive terminals are touched on our body get s shock?

0 Answers   FLS,

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