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