A460-V, four-pole. 50-hp, 60-Hz. Y-connected, three-phase induction motor devel- ops its full-load induced torque at 3.8 percent slip when operating at 60 Hz and 460 V. The per-phase circuit model impedances of the motor are R1=0.33 ohm Xm=30 ohm,X1= 0.42, X2=0.42 ohm Mechanical, core, and stray losses may be seglected in this problem. (a) Find the valuc of the rotor resistance R2 (b) Find Tmax,Smax and the rotor speed at maximum torque for this motor. (c) Find the starting torque of this motor, (d) What code letier factor should be assigned to this motor?

A460-V, four-pole. 50-hp, 60-Hz. Y-connected, three-phase induction motor devel- ops its full-load induced torque at 3.8 percent slip when operating at 60 Hz and 460 V. The per-phase circuit model impedances of the motor are R1=0.33 ohm Xm=30 ohm,X1= 0.42, X2=0.42 ohm Mechanical, core, and stray losses may be seglected in this problem. (a) Find the valuc of the rotor resistance R2 (b) Find Tmax,Smax and the rotor speed at maximum torque for this motor. (c) Find the starting torque of this motor, (d) What code letier factor should be assigned to this 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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A 460-V,4-pole, 50-hp, 60-Hz, Y-connected, three-phase induction motor develops its full-load induced torque at 3.8% slip when operating at 60 Hz and 460 V. The per-phase circuit model impedances of the motor are: R1=0.33 Ohms X1=0.42 Ohms Xm=30.0 Ohms X2=0.42 Ohms Mechanical, core, and stray losses may be neglected in this problem. a. Find the value of the rotor resistance. b. Find Tmax, SmaxT, and the rotor speed at maximum torque for this motor. c. Find the starting torque of this motor d. What starting code letter should be assigned to this motor?
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