Answer / rakesh ranjan sharma

It is the process by which the reversed polarity of residual magnetism can be corrected by using an external dc source to remagnetise the field poles in correct direction.........

Answer / monika

In alternators it is necessary to have some resudual
voltage to buildup an voltage. The residual voltages
weakens because of ageing & keeping at rest condition for
long time. In this cases using external DC sourses will
applied to field terminals to create residual. This process
is called as field flashing.

Answer / k.prakashchandra

Static exciter uses thyristors for converting AC to
DC .Thyristers require a minimum voltage to conduct,for
which the voltage created by residual magnetism is not
sufficient.To bring the generator volage to the required
value ,field flashing is done with dc source or AC through
rectifier.Once the required voltage is built up,the
generator output will take over the excitation with field
flashing off

Answer / kumar

I can't clear about this question but in alternator we
flash the field in RR(rotating rectifier)by give the Dc
voltage directly to field Its the method for developing AC
voltage

is KVAR (not reverse power) relay necessary to protect from excitor field failure on a brushless, synchroneus generator? Some people with previos experince tell me no but the manufacturers tell me it is designed for that purpose. Is it that it is only necessary for brushless generators and not the older style with the slip rings and brushes?

1 Answers  

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Why the Petrol Guns in the Petrol bunk are earthed?

3 Answers   ITC Infotech,

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Z transform is use when system is not a) converges b) diverges

0 Answers   CCP,

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suppose a fan is running with phase and neutral. if its neural is touched to body. then fan get stopped. if this fan is connected to phase and ground supply..then why it runs?

1 Answers  

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what's the thickness of 1.5sqmm wire

1 Answers   Bhel,

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How is operate breaker failure scheme in substation

0 Answers  

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WHY POLARITY TEST OF CT IS VERY IMPORTANT IN SWITCHGEAR

3 Answers   Birla, Reliance,

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what is the natural resistance of the earth? and how it effected by rain r snow? wat is the natural resistance of wet soil? define natural resistance?

1 Answers   ECL, ISRO,

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Why neutral is used in electrical system?

2 Answers  

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what is inductance function?

3 Answers  

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how much amps can i connect for 4core 120mm armade cable

2 Answers  

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

2 Answers   ABB, SK E&C, Sodexo,

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