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- A four-pole wave wound DC generator has 51 slots on its armature and each slot has 24 conductors. The flux per pole is 0.01 weber. At what speed must the armature rotate to give an induced emf of 220 V. What will be the emf developed if the winding is lap connected and the armature rotates at the same speed.
- Explain the requirement of starter in DC motor. With the help of suitable diagram, explain the working of 4-point starter.
- Explain the construction and operating principle of a single phase transformer with the help of suitable circuit diagram, phasor and necessary equations.
- A 100 kVA, 3300/200 V, 50 Hz single phase transformer has 40 turns on the secondary, calculate:
- (i) the values of primary and secondary currents.
- (ii) the number of primary turns.
- (ii) the maximum value of the flux.
- If the transformer is to be used on a 25 Hz system, calculate:
- (iv) the primary voltage, assuming that the flux is increased by 10%
- (v) the kVA rating of the transformer assuming the current density in the windings to be unaltered.
- Explain any two starting methods of Single Phase Induction Motor with the help suitable circuit diagrams.