7- Iron loss in the rotor of a 3-phase induction motor is negligible due to(a) Very low frequency of emf induced in the rotor(c) Very low flux density in rotor parts8- The starting current of a 3-phase induction motor is about(a) Half(c) 5 to 7 times(b) Twice(d) 8 to 10 times9- During plugging of an induction motor(a) Phase sequence is reversed(b) A de source is connected to stator(e) One phase is open circaited(d) Power is ied back to mains10- Direct online (D.O.L.) starter is used for induction motors(a)Less than 5 h.p. (b) Less than 10 h.p. (c) Greater than 10 h.p. (d) For any capacity(b) Very low emf induced in the rotor(d) Constant magnitude of flux linking the rotor coreof its full load rated current

In this question, We need to choose the correct options Iron losses in the rotor of the 3 phase…

7- Iron loss in the rotor of a 3-phase induction motor (a) Very low frequency of emf induced in the rotor (c) Very low flux density in rotor parts 8- The starting current of a 3-phase induction motor is negligible due to (b) Very low emf induced in the rotor (d) Constant magnitude of flux linking the rotor core is about-of its full load rated current

7- Iron loss in the rotor of a 3-phase induction motor (a) Very low frequency of emf induced in the rotor (c) Very low flux density in rotor parts 8- The starting current of a 3-phase induction motor is negligible due to (b) Very low emf induced in the rotor (d) Constant magnitude of flux linking the rotor core is about-of its full load rated current

Electric Motor Control

10th Edition

ISBN:9781133702818

Author:Herman

Publisher:Herman

Chapter39: Synchronous Motor Operation

Section: Chapter Questions

Problem 14SQ: Induction motors and welding transformers require magnetizing current, which causes a. lagging power...

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