The direction of rotation of a D.C. series motor can be changed by___________?
Correct answer: B. interchanging field terminals
- A. interchanging supply terminals
- B. interchanging field terminals
- C. either of A. and B. above
- D. None of the above
Explanation
Reversing only the field connections reverses the field relative to the armature current and hence reverses torque. Reversing the supply terminals reverses both field and armature currents, leaving the direction unchanged.
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