The following data were obtained on a 25- kVA, 2400:240-V, 60-Hz, single-phase distribution transformer:
• Open-circuit test with meters on LV side: 240 V, 3.2 A, 165 W
• Short-circuit test with meters on HV side: 55 V, 10.4 A, 375 W
Compute the worst voltage regulation and the power factor at which it occurs, when the transformer is delivering rated output at rated secondary terminal voltage of 240 V. Sketch the corresponding phasor diagram.