Olutions must include complete equivalent diagram(s). 12. a 2300 v, three-phase, 60 hz, y-connected, cylindrical-rotor synchronous motor hasa synchronous reactance of 11 0 per phase and a negligible resistance. when it delivers 200 hp, the efficiency is 90% and the torque angle, 6, 15°. determine: (a) the line-to-line excitation voltage; (b) the line current; (c) the power factor; (d) the absolute maximum power this motor could supply if the field current remains constant. 13. a 25 mva, 60 hz, single phase transformer has a voltage rating of 4.0 kv/39 kv. an open- circuit test is conducted from the low-voltage side, and the corresponding instrument readings are 4.0 kv, 62 a, and 68 kw. similarly, a short-circuit test from the low-voltage side gives readings of 325 v, 6.25 ka, and 51 kw. a. calculate the equivalent series impedance, resistance, reactance, core-loss resistance, and b. draw the approximate-equivalent circuit of the transformer referred to the low-side. (show c. calculate the efficiency of the transformer when it is supplying rated mva at rated voltage 14. the following details are known about a 200 hp, 500 v, 435 rpm de shunt motor: full-load magnetizing reactance of the transformer as referred to the low-voltage terminals all numerical values) to a unity power factor load connected to the low-voltage side. current is 330 a, insulation class is h, weight is 3400 kg, external diameter of the frame is 915 mm and length of the frame is 1260 mm. if the motor is running at full-load, calculate: a. the total losses and efficiency b, the approximate shunt field exciting current if the shunt field causes 15% of the total losses. the value of the armature resistance as well as the counter-emf, knowing that 45% of the c, total losses at full-load are due to armature resistance 15. a 3-phase 11 kv 50 hz squirrel cage induction motor draws a line current of 1.12 ka and a total power of 3.9 mw when operating at full load. the full-load speed is 490 rpm. the stator is wye connected and has an effective resistance per phase of 28.6 mω the stator iron (core) loss is 46 kw; friction and windage losses are 22.7 kw. calculate at full-load conditions: (a) the power factor; (b) power supplied to the rotor; (c) slip; (d) rotor i'r (copper) losses; (e) developed (mechanical) torque; ()efficiency