12Why does DC motor sometimes run too fastwhen under-loaded? *Due to high line voltageO all of the aboveDue to armature reactionO Due to weak fieldDue to brush-shifted to neutral

Q. Why does DC motor sometimes run too fast when under-loaded? Ans. Due to weak field Explanation…

Answered: 12 Why does DC motor sometimes run too…

12 Why does DC motor sometimes run too fast when under-loaded? * O Due to high line voltage O all of the above O Due to armature reaction O Due to weak field Due to brush-shifted to neutral

Electric Motor Control

10th Edition

ISBN:9781133702818

Author:Herman

Publisher:Herman

Chapter43: About Dc Motors

Section: Chapter Questions

Problem 1SQ

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Concept explainers

DC Series Motors

A DC motor is a type of electric motor which converts electric energy into mechanical energy. The forces that are produced by the magnetic field are what those common types of motors rely upon. Either electro-mechanical or electronic, all types of DC motors have some internal mechanism to change the current direction in part of the DC motors. As the DC motors could be powered from existing DC lighting power distribution systems, these motors were the first form of motors widely used. By changing the strength of the current in its field winding or by using a variable supply voltage, the speed of the DC motors can be controlled over a wide range.

Question

12
Why does DC motor sometimes run too fast
when under-loaded? *
Due to high line voltage
O all of the above
Due to armature reaction
O Due to weak field
Due to brush-shifted to neutral

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