A 155 V, DC separately excited motor drives a constant-torque load at 1400 rpm speed.The armature and field resistances are 0.7 N and 150 2, respectively. The motor draws a linecurrent of 10 A at the given load and the field voltage is 103 V. Answer the followingquestions.1- Calculate the resistance that should beadded Radd 2 to the armature circuit toRaddreduce the speed by 95%.RaddΩ2- Calculate the efficiency of the motorwithout the added Radd N if theE.I,rotational losses is equal to 162.07 W.V; RfV,%3- Calculate the efficiency of the motorRawith the added Radd N if the rotationallosses is equal to 162.07 W.n =%4- Calculate the resistance that must be added to the armature circuit to operate the motor atthe holding condition.RaddU

Given V=155 V Constant torque load N1= 1400 rpm Ia=0.7 ohm If= 150 ohm IL=10 A Vf=103 V

A 155 V, DC separately excited motor drives a constant-torque load at 1400 rpm speed. The armature and field resistances are 0.7 N and 150 N, respectively. The motor draws a line current of 10 A at the given load and the field voltage is 103 V. Answer the following questions. 1- Calculate the resistance that should be added Radd 2 to the armature circuit to If Radd 1 reduce the speed by 95%.

A 155 V, DC separately excited motor drives a constant-torque load at 1400 rpm speed. The armature and field resistances are 0.7 N and 150 N, respectively. The motor draws a line current of 10 A at the given load and the field voltage is 103 V. Answer the following questions. 1- Calculate the resistance that should be added Radd 2 to the armature circuit to If Radd 1 reduce the speed by 95%.

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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