By Surendra | June 11, 2020 0 Comment 0% 0 Created by Surendra 3 Phase Induction Quiz in English Set 1 All Important Question Answers for Electrician Related Exams 1 / 20 Which of the following methods is easily applicable to control the speed of the squirrel-cage induction motor ? Rotor rheostat control By injecting e.m.f. in the rotor circuit By changing the number of stator poles By operating two motors in cascade 2 / 20 A double squirrel-cage induction motor has two parallel windings in stator two parallel windings in rotor two series windings in stator two rotors moving in oppsite direction 3 / 20 The speed of a squirrel-cage induction motor can be controlled by all of the following except changing winding resistance changing number of poles changing supply frequency reducing supply voltage 4 / 20 The crawling in the induction motor is caused by low voltage supply harmonics developed in the motor improper design of the machine high loads 5 / 20 The shaft of an induction motor is made of hollow flexible any of the above stiff 6 / 20 The frame of an induction motor is usually made of bronze aluminium cast iron silicon steel 7 / 20 In medium sized induction motors the slip is generally around 0.004 0.14 0.04 0.0004 8 / 20 For which motor the speed can be controlled from rotor side ? Slip-ring induction motor Squirrel-cage induction motor Both and (2) None of the above 9 / 20 Which of the following component is usually fabricated out of silicon steel ? Shaft None of the above Stator Core Bearings 10 / 20 In the circle diagram for induction motor the diameter of the circle represents running torque line voltage rotor current slip 11 / 20 Size of a high speed motor as compared to low speed motor for the same H.P. will be same smaller any of the above bigger 12 / 20 In case of the induction motors the torque is directly proportional to slip inversely proportional to slip inversely proportional to (Vslip) directly proportional to (slip)2 13 / 20 The auto-starters (using three auto transformers) can be used to start cage induction motor of the following type none of the above star connected only delta connected only and both 14 / 20 The maximum torque in an induction motor depends on square of supply voltage all of the above rotor inductive reactance frequency 15 / 20 The shaft of an induction motor is made of stainless steel carbon steel cast iron high speed steel 16 / 20 DOL starting of induction motors is usually restricted to low horsepower motors variable speed motors high speed motors high horsepower motors 17 / 20 A 3-phase induction motor stator delta connected is carrying full load and one of its fuses blows out. Then the motor will stop and carry heavy current causing permanent damage to its winding will continue running without any harm to the winding will continue running burning its two phases will continue running burning its one phase 18 / 20 The injected e.m.f. in the rotor of induction motor must have the same phase as the rotor e.m.f. zero frequency high value for the satisfactory speed control the same frequency as the slip frequency 19 / 20 Stepless speed control of induction motor is possible by which of the following methods ? E.M.F. injection in rotor circuit None of the above Cascade operation Changing the number of poles 20 / 20 When the equivalent circuit diagram of doouble squirrel-cage induction motor is constructed the two cages can be considered in parallel with stator in parallel in series in series-parallel कृपया सही सूचना भरें ताकि सर्टिफिकेट ईमेल पर भेजा जा सकें। NameEmailPhone NumberDistrictSchool/Coaching Name Your score is LinkedIn Facebook VKontakte 0% Restart quiz आपको यह क्विज अच्छी लगी तो 5 स्टार रेटिंग जरुर दें । Send feedback
