spinning industry, a 205 V, 6 pole shunt motor runs at a speed of 1250 rpm gives an output of 7 HP with an armature current of 38 A. The armature winding is wave connected and it has 690 conductors. Its armature resistance is 0.3 and drop at each brush is 1 V. Find (i) Useful torque, (ii) Total torque, (iii) Useful flux per pole and (iv) Rotational losses occurring in the motor. [

spinning industry, a 205 V, 6 pole shunt motor runs at a speed of 1250 rpm gives an output of 7 HP with an armature current of 38 A. The armature winding is wave connected and it has 690 conductors. Its armature resistance is 0.3 and drop at each brush is 1 V. Find (i) Useful torque, (ii) Total torque, (iii) Useful flux per pole and (iv) Rotational losses occurring in the motor. [

Delmar's Standard Textbook Of Electricity

7th Edition

ISBN:9781337900348

Author:Stephen L. Herman

Publisher:Stephen L. Herman

Chapter30: Dc Motors

Section: Chapter Questions

Problem 4RQ

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Similar questions

A 4 pole, 250 V, DC shunt motor has a lap connected armature with 960 conductors. The flux per pole is 2x10-2Wb. Calculate the torque developed by the armature and the useful torque in Nm when the current taken by the motor is 30 A. The armature resistance is 0.12 ohm and the field resistance is 125 ohm. The rotational losses 825 W.
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