Conductive particles washed into these spaces will eventually ______ ___, requiring removal of the armature for repairs.

• A. short out
• B. burn insulation
• C. magnetize
• D. insulate

Answer: (A)

When a DC generator armature spins, conductive debris that finds its way into the gaps between the commutator bars and the winding slots can create unintended electrical bridges. These bridges provide a low-resistance path between adjacent commutator segments, so as the machine operates current can flow through the debris instead of only through the designed winding path. That results in short circuits within the armature, causing arcing, overheating, and potential damage. Because removing and cleaning the armature is the reliable way to access and remove the debris, this is the correct outcome. The other possibilities don’t fit the situation: the debris doesn’t purposely insulate or magnetize the circuit, and insulation damage isn’t the immediate consequence of conductive particles in these spaces.