The speed of a DC shunt motor can be made more than full load speed by __________(a) Reducing the field current(b) Decreasing the armature current(c) Increasing the armature current(d) Increasing the excitation currentThe question was asked during an online exam.Question is from Speed Control Using Field Control of Shunt Motor topic in section DC Motors of DC Machines

The speed of a DC shunt motor can be made more than full load speed by

1.	The speed of a DC shunt motor can be made more than full load speed by __________(a) Reducing the field current(b) Decreasing the armature current(c) Increasing the armature current(d) Increasing the excitation currentThe question was asked during an online exam.Question is from Speed Control Using Field Control of Shunt Motor topic in section DC Motors of DC Machines
Answer» Right answer is (a) Reducing the field current To explain I would say: Speed of the DC motor obtained from speed equation is inversely proportional to flux PRODUCED by the field. So, reducing the field current flux produced by armature will decrease, and speed will INCREASE.

Discussion

No Comment Found

Related InterviewSolutions

For which of the following motor dynamic braking is very effective?(a) Shunt motors(b) Separately excited motors(c) Series motors(d) Differential compound motorsThe question was asked by my college professor while I was bunking the class.Question is taken from Braking of DC Motors topic in portion DC Motors of DC Machines
When is the dynamic braking is employed?(a) Non-reversing drive(b) Reversing drive(c) Both Reversing and Non-reversing(d) Cannot tellI had been asked this question in an internship interview.My query is from Braking of DC Motors topic in division DC Motors of DC Machines
Which method of braking is generally used in elevators?(a) Plugging(b) Regenerative braking(c) Rheostatic braking(d) Mechanical brakingI had been asked this question during an internship interview.Question is taken from Braking of DC Motors in section DC Motors of DC Machines
Where dynamic braking is used?(a) Shunt motors(b) Series motors(c) Compound motors(d) All DC motorsI have been asked this question during an online interview.My enquiry is from Braking of DC Motors in portion DC Motors of DC Machines
Regenerative method of braking is based on ___________(a) Back emf is less than the applied voltage(b) Back emf is equal to the applied voltage(c) Back emf of rotor is more than the applied voltage(d) Cannot be determinedI have been asked this question during an interview.My question is taken from Braking of DC Motors topic in section DC Motors of DC Machines
During regenerative braking of DC motors ____________(a) Motor will run as a generator(b) Motor will reverse in direction(c) Motor will run at reduced speed(d) Motor will run as free rotating shaftI had been asked this question in a national level competition.My doubt stems from Braking of DC Motors in section DC Motors of DC Machines
The plugging braking gives the _____________(a) Zero torque braking(b) Smallest torque braking(c) Highest torque braking(d) Variable torque brakingI have been asked this question in an online quiz.Question is taken from Braking of DC Motors topic in division DC Motors of DC Machines
If the terminals of armature of DC motor are interchanged, this action will offer following kind of electrical braking ______________(a) Regenerative(b) Plugging(c) Dynamic braking(d) Depends on other parametersThe question was posed to me in my homework.This is a very interesting question from Braking of DC Motors topic in division DC Motors of DC Machines
Which of the following method is not used for regeneration?(a) Increasing field current(b) Increasing armature speed(c) Increasing supply voltage(d) Reducing supply voltageI have been asked this question in exam.My query is from Braking of DC Motors in chapter DC Motors of DC Machines
Regeneration is not easily possible for ____________(a) DC shunt motor(b) Separately excited motor(c) Compounding motor with weak series compounding(d) DC series motorThe question was asked in examination.My question is taken from Braking of DC Motors topic in division DC Motors of DC Machines

Discussion

No Comment Found

Related InterviewSolutions

Reply to Comment