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In: Electrical Engineering

1. three-phase induction motor rated 250 hp, 0.7 pf and 80% efficiency. Determine the minimum size...

1. three-phase induction motor rated 250 hp, 0.7 pf and 80% efficiency. Determine the minimum size in kVAR of a capacitor needed to prevent overloading the transformers.Two single-phase transformers each rated 150 kVA are connected open delta supplying a

2. A 2.2 kV, 200 hp, delta- connected, 3 phase synchronous motor is operating on full load at an efficiency of 0.88 and pf of 0.8 leading. The armature has a reactance per phase of 5 ohms and negligible resistance. Solve the induced emf per phase.

3.The result of the no load test on a three phase wye connected induction motor are as follows: line to line voltage = 400 V; Input power = 1770 W; Input current = 18.5 A; friction and windage loss = 600 W. determine the magnetizing reactance per phase.

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