A series motor runs at 800 r/min when the voltage is 400 V and the current is 25 A. The armature resistance is 0.4 ohm and the Series field resistance is 0.2 ohm. Determine the following: (a) The constant of the motor. If the speed decreases to 600 r/min,the torque increases by 32% and the field increases by 10%, determine the following: (b) The new armature current. (c) The new field current. (d) The new total resistance of the motor in ohm. (e) The additional resistance inserted in series with the motor in ohm.

A series motor runs at 800 r/min when the voltage is 400 V and the current is 25 A. The armature resistance is 0.4 ohm and the Series field resistance is 0.2 ohm. Determine the following: (a) The constant of the motor. If the speed decreases to 600 r/min,the torque increases by 32% and the field increases by 10%, determine the following: (b) The new armature current. (c) The new field current. (d) The new total resistance of the motor in ohm. (e) The additional resistance inserted in series with the motor in ohm.

Delmar's Standard Textbook Of Electricity

7th Edition

ISBN:9781337900348

Author:Stephen L. Herman

Publisher:Stephen L. Herman

Chapter5: Resistors

Section: Chapter Questions

Problem 1PA

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