1. A double squirrel-cage induction motor has two rotors moving in opposite direction two parallel windings in the stator two parallel windings in the rotor two series windings in the stator 2. The starting torque of a squirrel-cage induction motor is low negligible same as the full-load torque slightly more than full-load torque 3. The <a title=Three Phase Induction Motor MCQs class. 117.If a squirrel-cage induction motor having a rated slip of 2% on full-load has a starting torque of 0.5 full-load torque, then starting current is. a) equal to full-load current; b) twice full-load current; c)four times full-load current. d) five times full-load current; Answer: five times full-load current 118 6. The squirrel cage rotor of a 6 pole induction motor can be used for.. induction motor. (A) only 6 pole (B) 6 or 12 pole (C) any number of poles in an (D) none of the above . Ans: (C) any number of poles in an . 7. The squirrel cage motors are provided with blades in order to (A) facilitate cooling of the rotor (B) balance the rotor. Multiple Choice Question (MCQ) of Induction Motors page-4. 31. Advantage of slip ring induction motor over squirrel cage induction motor is The induction motor speed decreases by a few percent when the motor goes from no load to full-load operation. The full-load speed is a function of the motor design and power and is usually in the range of 94-99% of the synchronous speed; the difference is the slip. Figure 2 shows the typical construction of a squirrel-cage induction.
What is Squirrel Cage Induction Motor. A 3 phase squirrel cage induction motor is a type of three phase induction motor which functions based on the principle of electromagnetism.It is called a 'squirrel cage' motor because the rotor inside of it - known as a 'squirrel cage rotor' - looks like a squirrel cage MCQ in AC Motors part 3 of the Series as one of the Electrical Engineering topic in REE Board Exam. A pinoybix mcq, quiz and reviewers. Menu. New! Math; One of the speeds of a 2-speed squirrel cage induction motor is 800 rpm (lower speed). The other speed would be. A. 400 rpm. B. 2400 rpm. C. 1600 rpm. D. 1200 rpm. View Answer: Answer.
100 Most Important MCQ on Electric Drive | Industrial Drive MCQ-2020 February 27, 2021 Ques 41. A pole changing type squirrel cage motor used in derricks has four, eight and twenty-four poles 27.Which of the following statement about a double squirrel cage induction motor is incorrect ? (a) It has better speed regulation than squirrel cage motor. (b) Its upper cage is of low resistance and lower cage of high resistance. (c) It is particularly useful where frequent starting under heavy loads is required
Fig.1 Squirrel Cage rotor. In Squirrel cage induction motors the rotor is simplest and most rugged in construction. Cylindrical laminated core rotor with heavy bars of copper or Aluminum is used for conductors The advantages of a slip-ring induction motor over a squirrel cage induction motor is that. A. It has higher efficiency. B. It has higher power factor. C. It can be started with the help of rotor resistance starter. D. None of the above. Answer/ Hin Main disadvantage of squirrel cage induction motor is that they have poor starting torque and high starting currents. Starting torque will be in the order of 1.5 to 2 times the full load torque and starting current is as high as 5 to 9 times the full load current
. Squirrel-cage induction motor is finding increasing application in high-power servo systems because new methods have been found to (a) increase its rotor resistance (b) control its torque (c) decrease its intertia (d) decouple its torque and flux. Answer: c) Squirrel-cage induction-motor. d) Single-phase motor . Q2. The speed of rotor of an induction-motor is: a) The same as the synchronous speed. b) Higher than the synchronous speed. c) Lesser than the synchronous speed. d) Determined by the frequency and the number of poles . Q3. Squirrel-cage induction-motor differs from a slip-ring induction.
. A. To reduce the magnetic hum and locking tendency of the rotor. B. To increase the tensile strength of the rotor bars. C. To ensure easy fabrication. D. None of the above. Answer/ Hin Multiple choice questions on Induction motor with brief explanatory answers. The number of rotor bars in squirrel cage induction motor is generally a prime number. When of following is the correct statement about rotor reactance of induction motor running at full load 3-phase-induction-motor-mcq, 3 Phase Induction Motor Objective type question answer. 3-phase-induction-motor-mcq, 3 Phase Induction Motor Objective type question answer. Home; About; 10 Most of the squirrel cage motor has a slip percentage. (A) 2 to 5% (B) 1 to 5% (C) 2 to 7% (D) 2 to 8% Answer- (A) 11 is the formula to find the rotor.
In a squirrel cage motor the induced e.m.f. is a) Dependent on the shaft loading b) Dependent on the number of slots c) Slip times the stand still e.m.f. induced in the rotor d) None of the abov 7. When smooth and precise speed control over a wide range is desired, the motor preferred is. A. Synchronous motor B. Squirrel cage induction motor C. Wound rotor induction motor D. Dc motor E. None of the abov In the squirrel-cage induction motor, the number of slip rings is usually? (a) two (b) three (c) four (d) none; Ans: d. 14. In a squirrel-cage induction motor, the starting torque is usually? (a) low (b) negligible (c) same as full-load torque (d) slightly more than full-load torque; Ans: a. 15. The double squirrel-cage induction motor has two Induction Motor MCQ #12 Learn Polyphase Induction Motors MCQ questions & answers are available for a Electrical students to clear exams. Electrical Article. 133) In squirrel cage induction motors, the rotor slots are usually given slight skew to reduce . windage losses. eddy currents. accumulation of dirt and dust 3-phase induction motor MCQ questions with an answer - In squirrel cage induction motors, rotor slots are usually given slight skew t
Electrical Drives MCQ Test & Online Quiz: Below is the Electrical Drives MCQ Test that checks your basic knowledge of the Electrical Drives. This Electrical Drives MCQ Test contains 20 Multiple Choice Questions. You have to select the right answer to the question. Finally, You can also attempt Online Quiz from the Take Electrical Drives Quiz Button A squirrel-cage rotor (10) includes a laminated core (14) fixed to a rotor shaft (12), a plurality of secondary conductors (18) arranged respectively in a plurality of through holes (16) formed through the laminated core (14), a pair of end rings (20) connected to the secondary conductors (18) at axial ends of the laminated core (14), and a pair of reinforcing members (22, 23) respectively. (a) slip ring induction motor (6) squirrel cage induction motor (c) both (a) and (b) (d) none of the above. Ans: b . 94. A squirrel cage induction motor is not selected when (a) initial cost is the main consideration (b) maintenance cost is to be kept low (c) higher starting torque is the main consideration (d) all above considerations are. . The figure itself depicts many difference between the two types of motors. Don't worry, difference between Squirrel Cage and Slip Ring type Induction Motor is tabulated after the figure Three can be three ways to control the speed of squirrel cage induction motor. Voltage changes; Frequency changes; Stator poles; Voltage changes; First method is by means of changing the input voltage applied for excitation of stator winding. Although it looks simple to change the value of voltage, however very large change in voltage is.
Induction motors will not run at super synchronous speed by it's own. It requires an external force to pull it's speed above synchronous speed. Example: an electric vehicle driven by induction motor will run at super synchronous speed when it move.. The stator of an induction motor contains 3 'single phase windings'. When three currents pass through these windings at an angle of 120 degrees a rotating magnetic field is generated. This rotation of field is known as the synchronous speed. While using the term, 'speed of the motor' we mean this synchronous speed Induction Motor MCQs with Answers - Set 02 MCQ Polyphase Ind Motors Edit Practice Test: Question Set - 02 Squirrel cage induction motor only but not with slip ring motor (C) Squirrel cage as well as slip ring induction motor (D) None of the above. Correct Answer. 2. Insertion of resistance in the stator of an induction motor
6. The motor which has high starting torque: Squirrel cage induction motor; Slip ring induction motor; Correct answer: b. Slip ring induction motor. 7. The synchronous speed of a 4 pole machine operated at 50 Hz is: 200 r/min; 1500 r/min; 10,000 r/min; 50 r/min; Correct answer: b. 1500 r/min. 8. Commonly, the power factor of a single phase. In squirrel cage induction motors, the rotor slots are usually given slight skew in order to (A) Reduce windage losses (B) Reduce eddy currents Multiple Choice Questions with Answers on Refrigeration and Air-Conditioning - Set 07. Practice Test: Question Set - 07 1 Important Industrial Drive Multiple Choice Questions and Answers. 6. The range of ratings of electric motor used for rolling mills is of the order of A. 10 to 25 kW B. 25 to 85 kW C. 85 to 400 kW D. 400 to A. Squirrel cage induction motor and synchronous motor
The starting torque of a squirrel-cage induction motor is the turning effort or torque which the motor exerts when full voltage is applied to its terminals at the instant of starting. The amount of starting torque which a given motor develops depends, within certain limits, on the resistance of the rotor winding Squirrel Cage Induction Motor. Slip Ring Induction Motor. Tags: Question 6 . SURVEY . 60 seconds . Q. Q. Single phase induction motors are having only squirrel cage rotors . answer choices . yes. no. Tags: Question 14 . SURVEY . 30 seconds . Q. the speed of the magnetic field of stator is called as A three-stack VR stepper motor has a step angle of 10º. What is the number of rotor teeth in each stack ? (a) 36 (b) 24 (c) 18 (d) 12 4. If a hybrid stepper motor has a rotor pitch of 36º and a step angle of 9º, the number of its phases must be (a) 4 (b) 2 (c) 3 (d) 6 5 A. squirrel-cage induction motors only B. slip ring induction motors only C. both A. and (b) D. none of the above. PakMcqs.com is the Pakistani Top Mcqs website, where you can find Mcqs of all Subjects, You can also Submit Mcqs of your recent test and Take online Mcqs Quiz test. INFO. Home; About Us
MCQ (Single Correct Answer) GATE EE 2002 If a 400 V, 50 Hz, star connected, 3 phase squirrel cage induction motor is operated from a 400 V, 75 Hz supply, the torque that the motor can now provide while drawing rated current from the supply Introduction. We have seen the classification of A.C. motors and discussed in detail the working principle, concept behind rotor rotation and many other aspects of induction motor. Now let us discuss in detail, the most common form of induction motor, the Squirrel cage induction motor. The reason for the name Squirrel cage is because of the type of rotor used in these motors The motor whose rotor is wound type such type of motor is called slip ring induction motor, whereas the squirrel cage motor, has a squirrel cage type rotor. The rotor of the slip ring motor has a cylindrical core with parallel slots, and each slot consists each bar. The slot of the squirrel cage motor is not parallel to each other Let us understand the various starting methods of squirrel cage induction motors like primary resistors, auto transformers & star-delta methods. Also lets get to know the methods which are used to control the speed of squirrel cage. Know how the speed control is easily achieved by changing the number of stator poles Question is ⇒ A squirrel cage induction motor having a rated slip of 4% of fullload has a starting torque same as the full-load torque. Which one of the following statements is correct? The starting current is, Options are ⇒ (A) equal to the full-load current., (B) twice the full-load current., (C) four times the full-load current, (D) five times the full-load current, (E) , Leave your.
motor performance. External resistance connected to slip-ring and 1. Increases the starting torque 2. Decreases the starting current 3. Used to control the speed of rotor. 26 State the main constructional differences between cage induction motor and slip-ring induction motor. Squirrel Cage Induction Motor Slip-ring Induction Motor Question 4 : Irrespective of the supply frequency,the torque developed by a squirrel cage induction motor is the same whenever_____is the same. Option-1 : supply voltage : Option-2 : external load: Option-3 : rotor resistance: Option-4 : slip spee In a squirrel cage induction motor, the rotor slots are—— As some of our MCQs pages are not working well, but we are working on it and it will be live (soon) Thanks for pointing the msg. Reply. Ahmed says: at . Hello if we have three phase ( 220 ) induction motor ( star connection ) and power supply changed to 380 3 phas A. slip ring motor only but not with squirrel cage induction motor B. squirrel cage induction motor only but not with slip ring motor C. squirrel cage as well as slip ring induction motor D. none of the abov D.C. series motors induction motors ⇒ In a induction motor if P is the power delivered to a rotor and s is the slip, then the power lost in the rotor as copper loss will be P/s sP s 2 P P/s 2 ⇒ In a squirrel cage motor the induced e.m.f. is dependent on the shaft loading dependent on the number of slots slip times the stand still e.m.f.
Squirrel cage induction motor: Type of alternating current induction motor in which the rotor winding has little resistance and thus carries very high current. To withstand high currents, the rotor structure is modified and more resembles a cage than a winding 5) In induction motor, greater the number of poles A) Lesser the frequency B) Greater the speed C) Lesser the speed D) All of these 6) A 4-pole three-phase induction motor has a synchronous speed of 25 rev/s. The frequency of the supply to the stator is: A) 500 Hz B) 100 Hz C) 25 Hz D) 50 Hz 7) The slip speed of an induction motor depends upon Squirrel cage motor and slip ring (wound rotor) motor and are the two types of induction motor. Slip ring induction motor is also known as wound rotor induction motor. Both these types of induction motor operates on the principle of faraday law of electromagnetic induction
Learn Polyphase Induction Motors MCQ questions & answers are available for a Electrical Engineering students to clear GATE exams, various technical interview, competitive examination, and another entrance exam. Polyphase Induction Motors MCQ question is the important chapter for a Electrical Engineering and GATE students. Page-10 section- MCQ ON ELECTRICAL ENGINEERING Q.1 A salient pole synchronous motor is running at no load. Q.3 The power factor of a squirrel cage induction motor is (A) low at light load only. (B) low at heavy load only. two-phase induction motor (C) A.C. operated universal motor (D) hybrid stepper motor. Ans: Electrical Machines MCQ Quiz Multiple Choice Questions and Answers. Electrical Machines Objective Question and Answer to prepare for competitive and entrance exams and test your skills on the topic. Professionals, Teachers, Students and Kids Trivia Quizzes to test your knowledge on the subject Well the shortest and the simpest answer would be the stator and the rotor. But there is more to it. Let's start with the parts that are visible to us when we look at an induction motor. 1. A metal housing, with ribs designed for natural cooling (..
If the rotor of a cage induction motor moves at a rotational speed of N s (1-s), where N s is the synchronous speed and s is the slip, then the frequency of the magnetic flux components in the air gap observed from the stator are the following:. 1. The stator magnetomotive force (m.m.f.) waves due to the applied stator winding currents at the line frequency f A squirrel cage rotor from an induction motor. This example is from a small air fan. Most modern induction motors have a rotor in the form of a squirrel cage. The cylindrical squirrel cage consists of heavy copper, aluminum, or brass bars set into grooves and connected at both ends by conductive rings that electrically short the bars together The first three starters are used for both squirrel cage and slip ring induction motor. It is therefore recommended that large three-phase squirrel-cage induction motors be started with a reduced voltage applied across the stator terminals at starting. Small motors below 5 HP ratings may however be started direct-on-line (DOL)
Where R 2 and X 2 are the rotor resistance and inductive reactance at starting respectively, E 2 is the rotor induced EMF. Here in this equation, the starting torque of the induction motor is proportional to the rotor resistance R 2. The starting torque in a squirrel cage motor is small because of its low rotor resistance and there is no way to insert external resistance as the winding is. I got stuck in an MCQ question. Which is as following : Q.1) power factor of a squirrel cage induction motor is : (a) Low at heavy load only (b) Low at light and heavy loads (c) Low at light load only (d) Low at rated load only. I am getting an answer from what I understand but answer is given some other option. telling which will bias opinions Just like any other motor, a 3 phase induction motor also consists of a stator and a rotor. Basically there are two types of 3 phase IM - 1. Squirrel cage induction motor and 2. Phase Wound induction motor (slip-ring induction motor). Both types have similar constructed rotor, but they differ in construction of rotor. This is explained further classifications of motor types available, but this paper will focus on single-phase AC induction squirrel cage motors which is where the largest number of motors are utilized in ventilation. On the following pages the basic operation and types of AC single-phase induction motor types will be covered