A 140 V, DC shunt motor drives a constant-torque load at 1100 rpm speed. The armature andfield resistances are 0.9 2 and 155 N, respectively. The motor draws a line current of 10.5 A atthe given load. Answer the following questions.1- Calculate the resistance that should beadded Radd N to the armature circuit to reducethe speed by 85%.RaddRaddΩ2- Calculate the efficiency of the motor withoutthe added Radd N if the rotational losses isM1Vtequal to 147 W.%TEa3- Calculate the efficiency of the motor with theadded Radd Nif the rotational losses is equal to147 W.%4- Calculate the resistance that must be added to the armature circuit to operate the motor atthe holding condition.Radd|||

Given V=140 V N=1000 rpm Ra=0.9 ohm Rsh =155 ohm IL=10.5 A

A 140 V, DC shunt motor drives a constant-torque load at 1100 rpm speed. The armature and field resistances are 0.9 N and 155 N, respectively. The motor draws a line current of 10.5 A at the given load. Answer the following questions. 1- Calculate the resistance that should be added Radd 2 to the armature circuit to reduce the speed by 85%. Radd Radd 2- Calculate the efficiency of the motor without the added Radd SN if the rotational losses is M1 Vt equal to 147 W. n = % 3- Calculate the efficiency of the motor with the added Radd Nif the rotational losses is equal to 147 W. |% 4- Calculate the resistance that must be added to the armature circuit to operate the motor at the holding condition. Radd

A 140 V, DC shunt motor drives a constant-torque load at 1100 rpm speed. The armature and field resistances are 0.9 N and 155 N, respectively. The motor draws a line current of 10.5 A at the given load. Answer the following questions. 1- Calculate the resistance that should be added Radd 2 to the armature circuit to reduce the speed by 85%. Radd Radd 2- Calculate the efficiency of the motor without the added Radd SN if the rotational losses is M1 Vt equal to 147 W. n = % 3- Calculate the efficiency of the motor with the added Radd Nif the rotational losses is equal to 147 W. |% 4- Calculate the resistance that must be added to the armature circuit to operate the motor at the holding condition. Radd

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...

See similar textbooks

Similar questions

A 220 V DC series motor runs drawing a current of 30 A from the supply. Armature and field circuit resistances are 0.4 and 0.1 respectively. The load torque varies as the square of the speed. The flux in the motor may be taken as being proportional to the armature current. To reduce the speed of the motor by 50% the resistance in ohms that should be added in series with the armature is
step by step
I need the answer as soon as possible
A 220-volt DC series motor is running at a speed of 800 r.p.m and draws 100 A. Total resistance of the armature and field is 0.1 ohm. 1. Calculate the speed when the torque is halved if the magnetic circuit is unsaturated. 2. If the torque was 250 N-m, calculate its new value when the current is doubled and the saturation is occurred
A DC shunt generator delivers 45 A at a terminal voltage of 220 V. The armature and the shunt field resistances are 0.01 2 and 44N respectively. The stray losses are 375 W. What is percentage efficiency of the DC generator
A 220 V shunt motor has an armature resistance of 0.5 ohm and takes a current of 40 A on full-loads. By how much must the main flux be reduced to raise the speed by 50% if the developed torque increased by 10 %
A 22 kW, 230 V Series DC motor runs at 750 rev/min at full load and draws 110 A from the supply. The resistance of the armature is 0.1250 and the series field 0.0250. Calculate the speed when the load is reduced such that the input current reduces to 56 A. Assume that the useful flux per pole at 110 A is 23.9 mWb and the flux for 56 A is be 15.5 mWb.
I need the answer as soon as possible
A 4-pole series motor has 800 lap connected armature conductors. At a certain load, the flux per pole is 60mWb and the total mechanical torque developed is 400 N-m. Calculate the line current taken by the motor and the speed at which it will run with a back emf of 400 V. Total motor resistance is 4 ohm. 14 Marks]
A 220 V shunt motor has an armature resistance of 0.4 ohm and field resistance of 140 ohm. The motor draws 6 A at 1600 rpm at no load. Calculate the speed and shaft torque if the motor draws 52 A at rated voltage.
A 240V dc series motor has armature and field resistances of 0.5 W and 1 W respectively. When running at 1200 rev min-1 the motor draws 15A from the supply. Calculate the torque delivered. A 2 W resistor is connected in series with the motor. The torque is adjusted so that the armature current remains unchanged. Calculate the new speed and torque
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.