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Answer :

For a D.C. machines laboratory following type of D.C. supply will be suitable induction motor D.C. generator set.

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Last Answer : The inertia constants of two groups of machines which do not swing together are M1 and M2. The equivalent inertia constant of the system is M1M2/M1+M2

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Last Answer : Ans:

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Last Answer : Ans:

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Last Answer : A 8-pole, DC generator has a simplex wave-wound armature containing 32 coils of 6 turns each. Its flux per pole is 0.06 Wb. The machine is running at 250 rpm. The induced armature voltage is 384 V

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Description : 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 ... 3.total field circuit resistance must be less than t critical value  4.armature speed must be very high

Last 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 ... .total field circuit resistance must be less than t critical value  4.armature speed must be very high

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Last Answer : The slight curvature at the lower end of the O.C.C. of a self-excited dc generator is due to magnetic inertia

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Last Answer : In a DC shunt generator working on load, the brushes are moved forward in the direction of rotation, as a result of this, commutation will Improve but terminal voltage will fall