B- A 460-V 50-hp six-pole, delta-connected 60-Hz three-phase induction motor has a full-load slip of 4 percent, an efficiency of 91 percent, and a power factor of 0.8 lagging. At start-up, the motor develops 1.75 times the full-load torque but draws 7 times the rated current at the rated voltage. C- What is the starting current of this motor by direct starting. D- What is the starting current of this motor by Star-delta starter. ro

B- A 460-V 50-hp six-pole, delta-connected 60-Hz three-phase induction motor has a full-load slip of 4 percent, an efficiency of 91 percent, and a power factor of 0.8 lagging. At start-up, the motor develops 1.75 times the full-load torque but draws 7 times the rated current at the rated voltage. C- What is the starting current of this motor by direct starting. D- What is the starting current of this motor by Star-delta starter. ro

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

Related questions

Q: A three-phase, Y-connected, 460-V (line-line), 37-kW, 60-Hz, four-pole induction motor has the…

A: For a 3-phase, Y-connected induction motor, the following parameters are given:line voltage V,line…

Q: A 6-pole, 60-Hz, Y-connected, three-phase induction motor develops a torque (Td) of 250 N.m at a…

A: According to question: The synchronous speed and slip of the motor is calculated as…

Q: A 3 phase, 50 Hz, 6 pole induction motor has a full load slip of 8 %. The Totor resistance is 0.005…

A: For the 3 phase induction motor, P=6 f=50 Hzsf=8%=0.08R2=0.005 Ω/phX2=0.008 Ω/ph It is asked to find…

Q: 50. A) The rotor conductors of the 3-phase double-squirrel-cage induction motor are used during the…

A: A. The rotor conductors of the 3-phase double-squirrel-cage induction motor are used during the…

Q: A 240-V, 900 rpm DC series motor takes 25 A at full load. The armature resistance is 0.2 Q and the…

Q: A three-phase induction motor is rated at 5 hp, 1760 rpm, with a line-to-line voltage of 220 Vrms.…

A: Speed regulation is independent of motor rating and voltage The only things needed are no load and…

Q: A 4-pole, 50-Hz induction motor has a full-load slip of 5%. Each rotor p resistance of 0.3 2 and…

A: In this question we will find ratio of maximum torque to full load torque and speed at which maximum…

Q: 21. A) At what percentage of slip is the pull-out or breakdown torque of a typical 3-phase…

A: Three phase induction motor is single excited system which is electrical analogy with secondary…

Q: Convert the following logic gate circuit into a Boolean expression, writing Boolean sub-expressions…

A: Given data:Required information:

Q: A three-phase, 50-Hz, 6-pole induction motor develops a useful torque of 120 Nm at full-load, while…

A: Here 3 phase induction motor is given and the rotor frequency is given so find the slip synchronous…

Q: im curious about #5 but its based on #4!

A: Solution Outline for Induction Motor Problem (#4)Assumptions:Neglecting mechanical, core, and stray…

Q: A 50-kW 440-V 50-Hz two-pole induction motor has a slip of 6 percent when operating at full-load…

A: It is given that:To find:

Q: - Three phase induction motor has rating of 50 kW, 960 rpm, 400 V. 50 Hz, 6-pole. The motor…

A: The polarity of the back EMF and armature voltage is not the opposite. As a result, the armature…

Q: A 10hp six-pole 60-Hz three-phase induction motor runs at 1090 rpm under full-load conditions.…

Concept explainers

Synchronous Motor

The synchronous motor is an AC electric type motor where at a steady-state the shaft rotation is synchronized with the supply current variable-frequency. To an integral number of AC cycles, the rotation period is exactly equal. The stator of the motor in the synchronous motor contains multi-phase AC electromagnets due to which a magnetic field is created that rotates in time with the oscillation of the line current. The rotor contains a permanent magnet and the rotor rotates in synchronization with the stator field at the same rate and provides the second synchronized magnetic field which is rotating in nature as a result. When the synchronous motor is supplied with independently excited multi-phase AC electromagnets on both the rotor and the stator, it is termed as a doubly-fed machine. The most widely used AC-type motors are the synchronous AC motor and the induction AC motors.

Question

of the above
B- A 460-V 50-hp six-pole, delta-connected 60-Hz three-phase induction motor has a full-load slip of
4 percent, an efficiency of 91 percent, and a power factor of 0.8 lagging. At start-up, the motor
develops 1.75 times the full-load torque but draws 7 times the rated current at the rated voltage.
C- What is the starting current of this motor by direct starting.
D- What is the starting current of this motor by Star-delta starter.
[8 Mark]
ON
S

Expert Solution

This question has been solved!

Explore an expertly crafted, step-by-step solution for a thorough understanding of key concepts.

SEE SOLUTION Check out a sample Q&A here

Step 1

VIEW

Step 2

VIEW

Step 3

VIEW

Step by step

Solved in 3 steps

SEE SOLUTION Check out a sample Q&A here

Knowledge Booster

Learn more about

Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, electrical-engineering and related others by exploring similar questions and additional content below.

Similar questions

1. A 10-hp, 4-pole, 25-Hz, 3-Ф induction motor is taking 9,100 watts from the line. The core loss is 290 watts; stator copper loss is 568 watts; rotor copper loss is 445 watts, and the friction and windage loss is 121 watts. Determine the output torque in Newton-meter. 2. For a three-phase induction motor having rotor circuit resistance of 6 ohms, maximum torque occurs at a slip of 0.6. Find the value of standstill rotor circuit reactance. 3. A 4 - pole, 3 - phase, 60 Hz squirrel-cage motor draws 21 A and 7 kW while driving its normal load. Under these conditions, its slip is 2%. When running idle, this motor draws 6 A and 580 W at normal voltage. With its rotor blocked, this motor draws 15 A and 500 W with 50 V applied. What is the output torque of this motor when driving its normal load. 4. A 4-pole, 50 Hz, 3- phase induction motor develops a maximum torque of 110 N-m at 1360 rpm. The resistance of the star-connected rotor is 0.25 Ω /phase. Calicul the value of resistance that must…
A) At what percentage of slip is the pull-out or breakdown torque of a typical 3-phase squirrel- cage induction motor reached? 21. a) 3% slip b) 10% slip c) 20% slip d) none of the above B) If load is increased beyond the breakdown torque, what happens to the speed of the motor? a) it stops b) it may speed up beyond its rated rpm c) its speed will not change, but its current will go down d) none of the above
1. The rotor resistance and reactance per phase of a three-phase wound rotor induction motor are 0.035 and 0.15 ohm respectively. If an additional resistance is added, the starting torque is one half of maximum torque and the full load torque is three-fourth of the maximum. Determine the following: a. Full load speed b. speed at maximum torque c. value of additional resistance per required to achieve these conditions.
B. The name-plate of a squirrel-cage induction motor has the following information: Rated power: 50 hp; rated voltage: 400 V; rated frequency: 50 Hz; rated speed: 1480 rpm. When the machine is run on no-load at rated voltage, it draws a stator current of 13.5 A at a power factor of 0.16 lagging. The stator winding resistance is 0.1 , the rotor winding resistance is 0.05 , the stator leakage inductance is 2 mH and the rotor leakage inductance is 2 mH. i. What is the synchronous speed of this machine? Calculate the no-load losses of the machine. ii. iii. Calculate the magnetizing inductance of this machine. iv. Calculate the stator current and its power factor when the machine runs at rated speed. Neglect the core-loss resistance in your calculation. V. vi. Calculate the rotor current and its power factor when the machine runs at rated speed. Calculate the developed torque when the machine runs at rated speed. Calculate the efficiency of the machine when it runs at rated speed. vii.