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