Electrical Machines
The result of slip test on a 3-phase, 20 KVA, 400 V, 50 Hz connected salient pole alternator is given below- Phase value: Vmax = 100 V, Vmin = 96 V, Imax = 10 A and I min = 7 A. The direct and quadranature axis reactances are respectively

  14.28 and 5.54 Ω.
 8.248 and 9.60 Ω.
 14.28 and 9.60 Ω.
 8.248 and 5.54 Ω.

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Electrical Machines
Short circuit test is performed on a transformer with a certain impressed voltage at rated frequency. If the short circuit test is now performed with the same magnitude of impressed voltage, but at frequency higher than the rated frequency then

 The magnetude of current will increase, but power factor will decrease.
 The magnitude will both increase.
 The magnitude of circuit as well as the power factor will decrease.
 The magnitude of current will decrease but the power factor will increase.

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Electrical Machines
Flashing the field of DC generator means

  neutralising residual magnetism.
 increasing flux density by adding extra turns of winding.
  making the magnetic losses forces parallel.
  creating residual magnetism by a DC source.

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Electrical Machines
What is/are the necessary conditions for voltage build up in self excited generator?

 Field winding should be properly connected to armature winding.
 Field winding resistance should be less than critical resistance.
All of these
 Poles should contain residual flux.

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