Question 62Electricity & Electronics - QMED
70% to passWhat should be included in performing proper maintenance of a DC motor's commutator?
Apainting the face of the commutator with insulating varnish
Bbaking the armature in an oven at 350°C for 8 hours annually
Ccoating the copper surface with light machine oil for the first four hours of operation
Dside-cutting the copper segments and undercutting the mica
AI Explanation
The correct answer is D) side-cutting the copper segments and undercutting the mica. The proper maintenance of a DC motor's commutator involves periodically side-cutting the copper segments and undercutting the mica between the segments. This helps maintain the proper clearance between the commutator segments and ensures the mica does not become flush with the copper, which can lead to short circuits and motor damage. The other options are incorrect - painting the commutator, baking the armature, or coating with oil are not standard maintenance procedures for a DC motor commutator.
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