The speed of a D.C. shunt motor is required to be more than full load speed. This is possible by______________?
Correct answer: A. reducing the field current
- A. reducing the field current
- B. decreasing the armature current
- C. increasing the armature current
- D. increasing the excitation current
- E. none of the above methods
Explanation
Speed of a shunt motor can be increased above its normal value by field weakening. Reducing field current reduces flux, and speed rises approximately inversely with flux.
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