Answer / aditya

over frequency occurs when the RPM of prime mover goes above the rated speed. This protection is basically for prime mover and gives a trip signal to the prime mover in case of overspeed so that the centrifugal forces dont damage the prime mover and alternator rotor. This is generally a result of faulty speed governor or sudden throw off or throw in of large magnitude. In addition overspeeding will also result in increase of supply frequency. certian electronic equipments are very sensitive to freq and get damaged hence over freq protection is given.

Determine the MVA rating of the power transformer given that 110/66 kV,1000 Amps. Folks how can i calculate the MVA rating with this Data??Plz Help........

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I have seen 1 video in which a person getting shock while standing at top of a train,i have 1 question? why the people sitting in the train doesn't get shock while that man getting shock from top of the train? How the earthing of train works?

17 Answers   Bhel,

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WHAT MEANT BY SEVICE FOCTOR?

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why we are using in reverse power relay in generator singranizing

1 Answers   Dalkia,

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how much earthings are mendatory at a 25kva sub station?

3 Answers   Bhel,

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What is the relationship between the sending end and receiving end?

4 Answers  

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what do you mean by PF correction. A motor is rated at 15 kw,415 volts, 0.7 pf and eff of 0.92. The powerfactor is improved to 0.98 by adding capacitors at the bus. calculate the current drawn by motor under full load condition before and after pf correction

5 Answers  

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what are the types in Relay?

1 Answers   PLA,

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What is the differences in phase to phase voltages between star and delta connections of stator?

1 Answers  

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sir, 3phase induction motor takes different pf and different KW in three phase while running,explain reason

0 Answers   UltraTech,

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why the generating / transmitting voltage is in the order of multiples of 11(ie 11kv,22kv,33kv......)

1 Answers  

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How can you calculate in detail the VA burden of current transformer used for Restricted earth fault protection? Please understand that the CT required here is Class PX or X. Also please show the calculations for knee point vtg, stabilizing resistor, magnetising current.

3 Answers  

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