How can the formation of grooves be prevented on the commutator of a DC machine?
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Answer: A. the brushes of opposite polarity should track each other
Explanation
Groove formation occurs when brushes of the same polarity track precisely in identical paths along the commutator. Ensuring that brushes of opposite polarity track each other distributes wear evenly across the entire active surface. This interlaced brush tracking pattern prevents localized ridging and maintains a smooth, cylindrical commutator profile. The commutator surface experiences continuous sliding friction from carbon brushes during normal machine operation. Uneven wear patterns create deep grooves that disrupt electrical contact and accelerate destructive sparking. Maintenance technicians stagger brush holder positions along the axial length of the commutator to ensure even tracking.
Option B is incorrect because tracking brushes of the same polarity in identical paths accelerates localized groove wear. Option C is wrong since brush position has a massive impact on whether grooves form on the commutator surface. Option D is incorrect because option A provides the correct engineering solution to prevent commutator grooving.
- Subject
- Engineering
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- Electrical Engineering
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- medium
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