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

Does VT metering core can be used for synchronizing.

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