Answer / manoj tyagi

DRF=1-efficency

Answer / kumar.latif

it is the ratio of total voltage capacity of a scr string
to sum of capacities of individual scrs.

If V is total capacity and v is individual thyristor
capacity then derating factor=V/(nv) where n is the no of
thyristors

Answer / saroj kumar

String Efficiency=Actual Voltage or Current/n* Individual Voltage or current.

Derating Factor= 1- String Efficiency
=1-V/n*v

Answer / nhatanael

how to determine number of thyristors in series. in hvdc valve converter.
to determine derating factor you first need to know number of thyristors connected in series...

why open circuit test is conducted on hv side and short circuit test is conducted on lv side of a transformer ?what is the reason for it ?

3 Answers   HCL, NTPC,

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how define the torque in ac drive. from electrical side in the drive friquency ,voltage and current three factor is there.

0 Answers  

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i have one transformer 1000kva, 11/.433kv. we are using 200/5 amp. ct unit for measuring purpose, & one 800 amp. V.C.B Unit for the same t/f operate, i wants to known the primary current of T/F is only 53 amp. why we used 800 amp. V.C.B ? & 200/5 amp. CT Unit.

4 Answers  

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why CT out put is 5 what ever the primary current.

2 Answers  

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we know the value of the power factor is 0.8, we know the power factor is not depends upon the load ,then why we cant design the power factor in transformer ?

1 Answers  

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why we use post insulators in no ofstacks at substation for supporting equipment ? why we not use single post insulator

3 Answers  

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Brief working principle of fluorcent tubelight,function of starter & choke.

3 Answers   Havells,

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What is industrial automation ??????

5 Answers  

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if dc excitation is used to produce manetic flux in rotating machines then ehy it is not used in transformers.

4 Answers  

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what is the voltage present in the telephone?

10 Answers   Infosys,

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Which type of DC generator is used for electric welding purposes and why?

1 Answers  

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If only R Phase is connected in 2 pole elcb, n is not connected than it will work or not in ground fault.

0 Answers  

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