Field control of DC motor

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Field control of DC motor

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asked Aug 9, 2017 by anonymous

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asked Mar 20, 2018 by anonymous

The speed of a D.C. shunt motor can be increased by?

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asked Mar 20, 2018 by anonymous

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The armature torque of the D.C. shunt motor is proportional to?

Last Answer : The armature torque of the D.C. shunt motor is proportional to armature current.

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Sparking, is discouraged in a D.C. motor because?

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Sparking at the commutator of a D.C. motor may result in?

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Which D.C. motor will be suitable along with flywheel for intermittent light and heavy loads?

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Which D.C. motor has got maximum self loading property?

Last Answer : Differentially compounded D.C. motor has got maximum self loading property.

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The current drawn by the armature of D.C. motor is directly proportional to?

Last Answer : The current drawn by the armature of D.C. motor is directly proportional to the torque required.

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In a D.C. series motor, if the armature current is reduced by 50%, the torque of the motor will be equal to?

Last Answer : In a D.C. series motor, if the armature current is reduced by 50%, the torque of the motor will be equal to 25% of the previous value.

509 views 1 answer

asked Mar 20, 2018 by anonymous

anonymous · Answer 1 · 2017-08-09T16:09:19+0000

Field control of DC motor

•In field control of DC motor terminal voltage is kept constant.

•The field flux (φ_f) is directly proportional to the field current (I_f) .

•Speed (N) is inversely proportional to field flux (φ_f) .

•So as the field flux (φ_f) will be less speed (N) will be more.

•If the current is less field flux (φ_f) is less hence the speed (N) will be more.

•We can control speed by field diverter method or by using tapped field control.

anonymous · Answer 2 · 2017-08-25T09:17:17+0000

Answer :

Field control of DC motor

answered Aug 25, 2017 by anonymous

Field control of DC motor

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