for the voltage built-up a self-excited D.C. generator, which of the following is not an essential

for the voltage built-up a self-excited D.C. generator, which of the following is not an essential condition. 

1.there must be some residual flux 

2.field winding mmf must aid the residual flux 

3.total field circuit resistance must be less than t critical value 

4.armature speed must be very high
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1 Answer

Answer :

for the voltage built-up a self-excited D.C. generator, which of the following is not an essential condition. 

1.there must be some residual flux 

2.field winding mmf must aid the residual flux 

3.total field circuit resistance must be less than t critical value 

4.armature speed must be very high

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