Question is ⇒ In a differentially compounded D.C. motor, if shunt field suddenly opens, Options are ⇒ (A) the motor will first stop and then run in opposite direction as series motor, (B) the motor will work as series motor and run at slow speed in the same direction, (C) the motor will work as series motor and run at high speed in the same direction, (D) the motor will not work and come to stop, (E) , Leave your comments or Download question paper.

Question is ⇒ In a differentially compounded D.C. motor, if shunt field suddenly opens, Options are ⇒ (A) the motor will first stop and then run in opposite direction as series motor, (B) the motor will work as series motor and run at slow speed in the same direction, (C) the motor will work as series motor and run at high speed in the same direction, (D) the motor will not work and come to stop, (E) , Leave your comments or Download question paper. Previous question Next question


Q1.	In a differentially compounded D.C. motor, if shunt field suddenly opens
A.	the motor will first stop and then run in opposite direction as series motor [Correct Answer]
B.	the motor will work as series motor and run at slow speed in the same direction [Wrong Answer]
C.	the motor will work as series motor and run at high speed in the same direction [Wrong Answer]
D.	the motor will not work and come to stop [Wrong Answer]
View Answer 7 -3 Explanation:- Answer : A Discuss it below : !! OOPS Login [Click here] is required to post your answer/result Help other students, write article, leave your comments

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⇒ Starters are used with D.C. motors because
these motors have high starting torque
these motors are not self-starting
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to restrict armature current as there is no back e.m.f. while starting

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⇒ In case of conductively compensated D.C. series motors, the compensating winding is provided
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Better speed control
Low cost
High starting torque
Wide speed range

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The direction of rotation will reverse
Motor will stop
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Motor will run at its normal speed in the same direction as it was running

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⇒ If the no-voltage release of a D.C. motor starter fails to work on resumption of supply after a break, the motor will
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Eddy current loss
Hysteresis loss
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the speed increases rapidly
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