A 2.4-kVA, 2400/240-V, 50-Hz, step-down transformer has the following
parameters: R, = 1.5 a, X, = 2.5 R, R, = 0.02 a, X, = 0.03 Q, R,, = 6 kR,
and X,, = 8 kR. It is operating at 80% of its load at unity power factor.
Using the exact equivalent circuit embodying the ideal transformer, determine the efficiency of the transformer. Also, sketch its phasor diagram.
