Answer / pillay

You need a magnetic field to produce electrical energy.This
can be produced from electro magnetic means . What if during
a power failure when the DG set usage is most wanted and the
electrical source from a battery is also not available say
due to battery failure or discharged battery.To avoid such
situation a permanent magnet is used instead for initial
excitation.

define differential current and restraining current in relays. how to calculate it by mathematically? post the formulaes.

4 Answers   Siemens, VPEC,

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How to perform a DC resistance test In Alternator and their proceduces?

0 Answers  

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what is the significance of per unit impedance ?

7 Answers   HP,

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what is the difference between squirrel cage & slip ring induction motor by construction & working principle ?

1 Answers   Sail,

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in conventional fan regulators how the current varies with speed?

0 Answers  

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What are the advantages of skewing of cage rotor conductors?

0 Answers  

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What will be the fault current of any system when its generation is 10% of BASE generation( FUll Load )?Will is 10% or the same as full base calculation?

0 Answers  

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why the active power flow of some line is increased when the active power of out is cut ?

0 Answers   TAFE,

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what is power factor

4 Answers  

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1sq mm dc powr cable can carry how much dc currnt

0 Answers  

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what is maintenance?how to explain

0 Answers  

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How out of step protection relay works?

0 Answers   APL,

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