Three-phase motor b. Single-phase motor A 100 hp, 440 volts three-phase, 60 hz induction motor operates with 92% efficiency, 0.85 power factor a а. c. DC Motor d. All of these load. What is the current of the motor?

Three-phase motor b. Single-phase motor A 100 hp, 440 volts three-phase, 60 hz induction motor operates with 92% efficiency, 0.85 power factor a а. c. DC Motor d. All of these load. What is the current of the motor?

Introductory Circuit Analysis (13th Edition)

13th Edition

ISBN:9780133923605

Author:Robert L. Boylestad

Publisher:Robert L. Boylestad

Chapter1: Introduction

Section: Chapter Questions

Problem 1P: Visit your local library (at school or home) and describe the extent to which it provides literature...

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2) A large 3-phase, 4000 Va (phase to phase), 60 Hz squirrel-cage induction motor draws a current of 385 A/phase. The total active power at the stator input terminals is 2344 kW, when operating at full load. The corresponding speed is accurately measured and found to be 709.2 r/min. The stator is connected in wye and the resistance between two stator terminals is 0.10 Q. The total iron losses are 23.4 kW and the windage and friction losses are 12 kW. Calculate the following: c) The total 1²-R losses in the rotor d) The load mechanical power (kW), torque (kN•m), and efficiency. S = Va · V3 - I S= Vy•3·I %3D
2) A large 3-phase, 4000 Va (phase to phase), 60 Hz squirrel-cage induction motor draws a current of 385 A/phase. The total active power at the stator input terminals is 2344 kW, when operating at full load. The corresponding speed is accurately measured and found to be 709.2 r/min. The stator is connected in wye and the resistance between two stator terminals is 0.10 Q. The total iron losses are 23.4 kW and the windage and friction losses are 12 kW. Calculate the following: a) The power factor at full load b) The active power supplied to the rotor c) The total 1²-R losses in the rotor d) The load mechanical power (kW), torque (kN•m), and efficiency. S = Va· V3 - I S- Vy·3•I
2) A large 3-phase, 4000 Va (phase to phase), 60 Hz squirrel-cage induction motor draws a current of 385 A/phase. The total active power at the stator input terminals is 2344 kW, when operating at full load. The corresponding speed is accurately measured and found to be 709.2 r/min. The stator is connected in wye and the resistance between two stator terminals is 0.10 Q. The total iron losses are 23.4 kW and the windage and friction losses are 12 kW. Calculate the following: a) The power factor at full load b) The active power supplied to the rotor c) The total 12.R losses in the rotor d) The load mechanical power (kW), torque (kN-m), and efficiency. S = Va• V3- I S= Vy 3•I %3D
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What will be the operating power factor of a 3-phase induction motor, whose ratings are 230 V, 50 Hz, 120 hp, and 4-poles? Motor is operating at rated conditions with an efficiency of 92% and draws a line current of 260 A. The core loss and stator copper losses are 1710 W and 2830 W respectively. (a) 0.85 (c) 0.93 (b) 0.90 (d) 0.80
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1) The magnitude of the resultant flux in two phase supply system is equal to: A. Pm B. Pm . Pm C. D. Фи E. 30m 2) The power input to the rotor of a 400 V, 50.Hz, 6-pole, 3-phase induction motor is 20 kW. The slip is 3%. The rotor copper losses will be: A. 600 W B. 666.66 W C. 60 W D. 6000 W E. 66 W 3) A 12 - pole, 3-phase alternator driven at a speed of 500 r.p.m. supplies power to an 8-pole 3-phase 2 induction motor. If the slip of the motor, at full-load is 3%, the full-load speed of the motor is: A. 727.5 B. 827.5 C. 888.5 D. 626.5 E. 226.5 4) It is advisable to avoid line-starting of induction motor and use starter because: A. motor takes five to seven times its full load current B. it will pick-up very high speed and may go out of step C. it will run in reverse direction D. starting torque is very high E. starting speed is very high 5) In a three-phase induction motor, the number of poles in the rotor winding is always: A. zero B. more than the number of poles C. less than number…
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Measured in the idle test of a three-phase star-connected induction motordata: 300 V / 2.2A / 145 W. In the short circuit test, 60 V / 25 A /680 W data measured. L type equivalent circuit for case where slip is 3%Find the current ( I2) flowing through the load resistor that varies due to shear.and obtain the electrical equivalent circuit of the motor in this state. Whole circuitto obtain the values of the elements properly andDraw the L-type electrical equivalent circuit by writing on the elementsMake your calculations and drawings legible. You find
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8. A 3-phase induction motor is running at 2% slip. If the input to rotor is 1000 W, then mechanical power developed by the motor is ............ (i) 20 W (iii) 500 W (ii) 980 W (iv) 200 W