A 4-pole, 115 V, 60 Hz, 1710 rpm, capacitor-start single-phase induction motor has been designedto produce maximum starting torque per unit starting current. The motor has the followingparameters: Rim=1.5ohms, Xim=2.6ohms, R1a=2.5 ohms, Xia=2.5 ohms, Xmag=40 ohms, R2=1ohms, X2=1.6 ohmsNa/Nm =1, Capacitor in series with auxiliary winding = 375 µF.a) Draw the equivalent circuit for the motor under starting conditions. Determine the value of thestarting torque.b) Draw the equivalent circuit for the motor when it runs at the rated (i.e., full load) speed. Determinethe torque developed at this speed.c) Determine the ratio of the starting torque to the torque developed at the rated speed.

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A 4-pole, 115 V, 60 Hz, 1710 rpm, capacitor-start single-phase induction motor has been designed to produce maximum starting torque per unit starting current. The motor has the following parameters: Rim=1.5ohms, XIm=2.6ohms, R1a=2.5 ohms, Xia=2.5 ohms, Xmag=40 ohms, R2=1 ohms, X2=1.6 ohms Na/Nm =1, Capacitor in series with auxiliary winding = 375 µF. %3D a) Draw the equivalent circuit for the motor under starting conditions. Determine the value of the starting torque. b) Draw the equivalent circuit for the motor when it runs at the rated (i.e., full load) speed. Determine the torque developed at this speed. c) Determine the ratio of the starting torque to the torque developed at the rated speed.

A 4-pole, 115 V, 60 Hz, 1710 rpm, capacitor-start single-phase induction motor has been designed to produce maximum starting torque per unit starting current. The motor has the following parameters: Rim=1.5ohms, XIm=2.6ohms, R1a=2.5 ohms, Xia=2.5 ohms, Xmag=40 ohms, R2=1 ohms, X2=1.6 ohms Na/Nm =1, Capacitor in series with auxiliary winding = 375 µF. %3D a) Draw the equivalent circuit for the motor under starting conditions. Determine the value of the starting torque. b) Draw the equivalent circuit for the motor when it runs at the rated (i.e., full load) speed. Determine the torque developed at this speed. c) Determine the ratio of the starting torque to the torque developed at the rated speed.

Delmar's Standard Textbook Of Electricity

7th Edition

ISBN:9781337900348

Author:Stephen L. Herman

Publisher:Stephen L. Herman

Chapter32: Three-phase Motors

Section: Chapter Questions

Problem 6RQ: Name three factors that determine the torque produced by an induction motor.

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