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 Stepless speed control of induction motor is possible by which of the following methods ? Changing the number of poles None of the above E.M.F. injection in rotor circuit Cascade operation 2 / 20 DOL starting of induction motors is usually restricted to high speed motors high horsepower motors low horsepower motors variable speed motors 3 / 20 In case of the induction motors the torque is inversely proportional to (Vslip) directly proportional to (slip)2 inversely proportional to slip directly proportional to slip 4 / 20 In the circle diagram for induction motor the diameter of the circle represents running torque slip line voltage rotor current 5 / 20 The speed of a squirrel-cage induction motor can be controlled by all of the following except changing number of poles reducing supply voltage changing supply frequency changing winding resistance 6 / 20 The shaft of an induction motor is made of flexible stiff any of the above hollow 7 / 20 When the equivalent circuit diagram of doouble squirrel-cage induction motor is constructed the two cages can be considered in parallel in series-parallel in series in parallel with stator 8 / 20 For which motor the speed can be controlled from rotor side ? Both and (2) None of the above Squirrel-cage induction motor Slip-ring induction motor 9 / 20 Which of the following component is usually fabricated out of silicon steel ? Bearings None of the above Stator Core Shaft 10 / 20 A double squirrel-cage induction motor has two parallel windings in rotor two parallel windings in stator two series windings in stator two rotors moving in oppsite direction 11 / 20 Which of the following methods is easily applicable to control the speed of the squirrel-cage induction motor ? By operating two motors in cascade By injecting e.m.f. in the rotor circuit By changing the number of stator poles Rotor rheostat control 12 / 20 The auto-starters (using three auto transformers) can be used to start cage induction motor of the following type and both none of the above delta connected only star connected only 13 / 20 The frame of an induction motor is usually made of aluminium silicon steel bronze cast iron 14 / 20 Size of a high speed motor as compared to low speed motor for the same H.P. will be same smaller bigger any of the above 15 / 20 The crawling in the induction motor is caused by low voltage supply high loads improper design of the machine harmonics developed in the motor 16 / 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 burning its one phase will continue running without any harm to the winding will continue running burning its two phases 17 / 20 The injected e.m.f. in the rotor of induction motor must have the same frequency as the slip frequency the same phase as the rotor e.m.f. high value for the satisfactory speed control zero frequency 18 / 20 The maximum torque in an induction motor depends on frequency rotor inductive reactance square of supply voltage all of the above 19 / 20 In medium sized induction motors the slip is generally around 0.0004 0.004 0.04 0.14 20 / 20 The shaft of an induction motor is made of stainless steel high speed steel cast iron carbon steel 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
