1.How to calculate backup time from series connected battery of 12v dc with 26Ah for 2battery?

3 Answers  

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why do we use UPF watt meter in short circuit test of the transformer and LPF watt meter in open circuit test of the transformer

2 Answers   Bell, TCS,

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when we change tha taps from 1-16 in 100mva tr whether a constant voltage avaliable till it reaches tap 16 or voltage change as per taps change

1 Answers  

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sir i want previous entrance exam papers for written test

0 Answers   Vizag Steel,

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What are the main problems in distribution? I have to do an assignment so which problem should I choose? Like power factor problem etc.

4 Answers  

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When in a large power system if the demand of power is larger than the generated power the frequency of the power system drops.(assume the rated frequency is 50Hz and now it is 49Hz) So does this mean the demand is totally supplied with a lower value of generated power in a lower frequency?

1 Answers  

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What are the different ratings of the fuse units for different distributions at your organization?

3 Answers   TATA, UPPCL,

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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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if field current decreases how can the speed increase in the unloaded dc series motor

1 Answers  

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iam preparing for rrb section engineer post in electrical branch.suggest the right textbook for my reference.fromwhere i will get the previous q.papers?

0 Answers   RRB,

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In Generator How suction compression power and exhaust works ?

0 Answers   Sify,

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Can we use droop CT in neutral in place of W phase of alternator ?

2 Answers  

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