Answer / nishad

My question is Why Earthing is not required in Xformer
primary star point of Star / Star connection????

Answer / k.prakashchandra

Eatrthing primary neutral of star/star Tr at the receiving
end is of no use for protection and safety . At sending end
neutral is earthed and it is sufficient.

I have 30KW Motor Starter Panel, System voltage is 480V, So i have to convert voltage 480 to 220V to give the contactor coil. How i can select control transformer, Which rating transformer i can use this panel, what is the procedure, please tell me.

2 Answers  

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what is tha online tapping and offline tappchange? which side connected primary or secondary and explain ?

4 Answers   Essar,

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What are the circuit models used for analysis of medium length transmission lines? Which one is superior? Support your answer.

1 Answers   UPSC,

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Explain working of PIU(Power Interface Unit) in Telecommunication,

7 Answers   ACME, ATC, Bharti, HCL, INDUS, Pace Pharmaceuticals,

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Write down the brushes of a de machine.

0 Answers  

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if we are using ACB in a panel the how much clearance do we need in panel room.

2 Answers  

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Please define ampere?

0 Answers  

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what are the industrail measures to over ferranti effect? how would the ferranti effect the power system if those remedial mearsure arent taken? how often does this effect occurs in real power system?

0 Answers  

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what is the HT motor current setting (Motor protection relay)aganist FLA If the capacitor is connected in parallal to the motor to increase the P.F from 0.89 to 0.99. the setting is to be reduced. what is the formula for to calculate the current.(FLA - CALCULATED CURRENT!= )

1 Answers  

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IC 741 is opampIC..moreover AND OR NOT ICs also have '74' in them.. why is that number specifically used?

1 Answers  

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What is meant by Guard relay ?

2 Answers  

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what is zero sequence curr ent ?

4 Answers  

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