Answer / abdul hameed

first we need DC current in the rotor second we need AVR this device controlled the the voltage which feeding the rotor.this
method is suitably for brush and brush less generator

Answer / vinod

EXTERNAL DC SOURCE

Answer / siddhu

In an alternator the rotor acts as a field winding it produces rotating flux when excited with dc current by an external dc source when this flux cuts the armature, current is induced in it.

what is the working principle of tube light?

2 Answers  

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What should be the amps for a MV fuses for transformer 630kVA 20(10)/0.4 kV

0 Answers  

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what is tpdt

4 Answers  

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if dc is better then ac...then why we are perfering ac over dc?eg:at home?

2 Answers  

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in flemings lefthand rule thumb indicate for....

2 Answers   APPSC,

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1)Why electric shock is feel ?? n in a Electric Train why we didnt feel that ? 2)What is the reason for transformer Noise ?? 3)What is relation b/w Transmission Lines & Communication Lines ? 4)Which material is used for making Transformer oil & How u measure its dielectric strength & Name the test ?

14 Answers   NTPC, Tata Power,

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What is the work of IGBT in ups?

2 Answers  

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what is V0/V rating of cable

1 Answers  

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why transformer comes only in standard rating like 11kv,33kv,66kv....and not like 33.33kv and so on?

3 Answers  

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whenever a squirrel or a crow gets tangled near the out put of the feild transformer there is a discharge of 440 volts of current through the neutral due to which my appliances blow up causing a huge bang.will the RCCB help in these conditions

1 Answers  

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why connecting surge unit in contactor coil

0 Answers  

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what is surge impedance loading and it's significant in power system?

2 Answers  

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