Why reactive power is needed in a power system? How is it being absorbed or delivered by alternators? For reactive power control we are changing excitation but reactive power absorbing or delivering related to stator. How these two are interlinked? i want a detailed explanation with necessary expressions and figures?

0 Answers   Power Plant,

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What are the types of earthing? Explain dagramatically.

3 Answers   Siemens,

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can we use 220 volt 15 w a.c. lamp on 220 volt d.c.

11 Answers   Philips,

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How much allowable difference current between on three phases Dear sir, We have a 1870 KW HT motor, 11 Kv supply,FLA-120A,2870 rpm,2-pole squirrel cage induction Motor.And stator is connected in star connection with Liquid resistance stater to limit the starting current.It has coupled with Centrifugal air compressor.My question is it is loading 73% of FLA taking R-phase 86.7 A, Y-phase-85.4A,B-phase- 78.3A.why the B phase current is that much of difference.Is it allowable, or any one tell me how much allowable current.If any method to calculate.

1 Answers  

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If induction motor load is incresed motor speed decrases.But in syncronous motor load incrases speed canstant why?

5 Answers  

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what is earth resistance? how to measured? and give values at power station and mcc area?

0 Answers   Essar,

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in the directional overcurrent and earthfault protection,normally we are setting the angle 45 deg lead for phase fault overcurrent and -45 deg lead for earthfault fro forward direction.but both the fault are operating on the same angle region only.why?how the relay will response?

0 Answers  

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Difference between online and offline UPS?

11 Answers  

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1 kva how much amps? How to calculate ?

2 Answers   L&T,

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what is meaning of phase angle in two phase.

5 Answers  

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what is the relation between voltage & frequency

11 Answers  

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How cmd is calculated in case of energy neters

0 Answers  

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