Answer / k.prakashchandra

Master Unit Sub-Station

what is ripple ??? what is harmonics ?

3 Answers   ABB,

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Sir we have 12.5 MVA(110/11KV) transformer (Y-Y) connected,which tripped showing earth fault,when we charged transformer it stood OK ,but on connecting 11 KV feeders it tripped showing earth fault.our service engineers found that the B phase and R phase phase connecting to neutral broken from HV OLTC(on load tap changer),and R phase and Neutral is ok.Dissolved gas analysis shows that accetline content is high,tan delta value is 12.My dout is it is an internal fault of transformer,why REF or diffrential relay is not acted?

1 Answers  

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How can we measure MVAR of a 3 phase transformer.....???

1 Answers   JLL, UPPCL,

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what is the prinsiple of dc motor and construction and working ,application of dc motor.

0 Answers  

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What are the ratings of VCB, MCB, MCCB, SF6, ACB, and OCB?

0 Answers  

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What is SNMP Card Monitoring in UPS???

2 Answers   Emerson, MAA, SNMP,

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Why rotating machines are not allowed to run near critical speed region?

2 Answers  

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how  do you choose the cable size as per amps rating & the voltage drop for the same.

0 Answers   C&W,

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How does ELCB work when exist earth foult? and How does RCCB work when exist earth foult?

1 Answers  

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Why size of HT cable is less then LT cable inspite of the fact that voltage is higher in HT cable?

2 Answers   L&T,

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Differene between KVA and KW.

6 Answers   Bharti,

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Why Indian Electricity frequency desined 50 Cycles as developed countrys are using high frequency with low voltage

1 Answers  

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