Satisfactory commutation of D.C. machines requires______________?
Correct answer: D. all of the above
- A. brushes should be of proper grade and size
- B. brushes should smoothly run in the holders
- C. smooth, concentric commutator properly undercut
- D. all of the above
Explanation
Good commutation depends on correctly sized and graded brushes, free brush movement in the holders, and a smooth, concentric, properly undercut commutator. Failure of any one of these can cause sparking.
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