The speed of a D.C. shunt motor more than its full-load speed can be obtained by_____________?
Correct answer: A. decreasing the field current
- A. decreasing the field current
- B. increasing the field current
- C. decreasing the armature current
- D. increasing the armature current
Explanation
Motor speed is approximately proportional to the back-emf divided by field flux. Reducing the field current weakens the flux and therefore raises the speed above its normal value.
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