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1012 ⏐⏐⏐ POLYPHASE SYSTEMS<br />

28. Repeat Problem 25 if each phase impedance is changed<br />

to a 12-� resistor in series with a 16-� inductive reactance.<br />

29. Repeat Problem 25 if each phase impedance is changed<br />

to a 20-� resistor in parallel with a 20-� capacitive reactance.<br />

SECTION 22.10 Power<br />

30. Find the total watts, volt-amperes reactive, volt-amperes,<br />

and Fp of the three-phase system of Problem 2.<br />

31. Find the total watts, volt-amperes reactive, volt-amperes,<br />

and Fp of the three-phase system of Problem 4.<br />

32. Find the total watts, volt-amperes reactive, volt-amperes,<br />

and Fp of the three-phase system of Problem 7.<br />

33. Find the total watts, volt-amperes reactive, volt-amperes,<br />

and Fp of the three-phase system of Problem 12.<br />

34. Find the total watts, volt-amperes reactive, volt-amperes,<br />

and Fp of the three-phase system of Problem 14.<br />

35. Find the total watts, volt-amperes reactive, volt-amperes,<br />

and Fp of the three-phase system of Problem 16.<br />

36. Find the total watts, volt-amperes reactive, volt-amperes,<br />

and Fp of the three-phase system of Problem 20.<br />

37. Find the total watts, volt-amperes reactive, volt-amperes,<br />

and Fp of the three-phase system of Problem 22.<br />

38. Find the total watts, volt-amperes reactive, volt-amperes,<br />

and Fp of the three-phase system of Problem 26.<br />

39. Find the total watts, volt-amperes reactive, volt-amperes,<br />

and Fp of the three-phase system of Problem 28.<br />

40. A balanced, three-phase, D-connected load has a line<br />

voltage of 200 and a total power consumption of 4800 W<br />

at a lagging power factor of 0.8. Find the impedance of<br />

each phase in rectangular coordinates.<br />

41. A balanced, three-phase, Y-connected load has a line<br />

voltage of 208 and a total power consumption of 1200 W<br />

at a leading power factor of 0.6. Find the impedance of<br />

each phase in rectangular coordinates.<br />

*42. Find the total watts, volt-amperes reactive, volt-amperes,<br />

and Fp of the system of Fig. 22.47.<br />

E AB = 125 V �0°<br />

E CA = 125 V � + 120°<br />

E BC = 125 V � –120°<br />

c<br />

20 �<br />

3 �<br />

15 �<br />

FIG. 22.47<br />

Problem 42.<br />

3 �<br />

a<br />

4 � n<br />

4 �<br />

4 �<br />

15 �<br />

20 �<br />

20 �<br />

15 �<br />

3 �<br />

b

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