Answer Number 8 Write your Solution Pls Box your Final answer. 43. Make a sketch showing how to insert three wattmetera in a four-wire three-phase41. What difficulties exist in the solution of a three-phase three-wire star-connectedcircuit that is unbalanced? Explain why a solution is facilitated when a starthe phase sequence is reversed? Boes- 115. The following unity-power-factor eurrents arephase BN is reversed, i.e., with the arrow in load BN directed from B to N, andpower factor of 0.99 (e = 8.1°). Calculate (a) currents INA and IBN, (b) neutral19. A two-phase three-wire circuit similar to that of Fig. 18-14 is connected so thatfactor of 0.6 lagging. Calculate the current in each phase and the total power.balanced?Load A consists of lighting circuits (power factor- 1) totaling 4,140 watts, andis an impedance of (9.6 - j7.2); load BA takes a current of 15 amp at a lagging10. The voltage across each phase of a four-wire two-phase systena (Fig. 18-13) is 115.11. The following information is given in connection with the two-phase three-wirecircuit of Fig. 18-14: EBA = 170; load NA is an impedance of (6 +j8); load BNload B representa lighting and motor circuits totaling 3,105 watta at a poweris transformed into an equivalent delta.42. Describe a four-wire three-phase system. What important advantages dopossess? What voltages are generally used for such a system?iystem to measure the total power.Problems1. The voltage across each phase of Fig. 18-4a is 120. (a) If points a and à aconnected what will be the voltage between A and B? (b) If a is joined toand e is joined to b, what will be the voltage between A and B? (e) If a is joinedto B, and b is joined to C, what will be the voltage between A and c?2. The voltage aaross each phase of Fig. 18-46 is 120. If points A and o are con.nected together, what will be the voltage between a and B?8. The voltage across each phase of a star-connected source is 265. What will bethe current in each of the three line wires if a balanced load of 200 kw at a powerfactor of 0.82 is delivered?4 What is the voltage of a delta-connected source that delivers an 0.85 power-factorload of 500 kw at 148 amp?6. A 10-hp 230-volt three-phase motor draws a line current of 25 amp when oper-ating at rated output. If the motor efficiency is 91 per cent, caloulate the powerfactor.6. Two balanced loads are connected in parallel to a three-phase 460-volt source.Load A is 900 kva at a power faotor of 0.6 lagging, and load B is 400 kw at apower factor of 0.8 leading. Caleulate (a) total kilowatts and kilovolt-amperes,(b) overall power factor, (e) line currents.&.7. A 234-volt three-phase source serves a balanced load consisting of three equalimpedances, each of which has a resistance of 3.6 ohms and an inductive resctanceof 4.8 ohms. Caleulate the line currents and the total power if the impedancesare connected in star.8. Solve Prob. 7 for a delta-connected load, assuming all other conditions to remainthe same.9. What ahould be the resistance and reactance of each of the impedances of Prob.if, when connected in delta, the line currents and the total pówer are to be tsame as for the star connection?%3Dcurrent IN, (c) line currents IA and Ia, (d) the total power.has voltages ENA - Exa

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8. Solve Prob. 7 for a delta-connected load, assuming all other conditions to remain the same.