D.C. machine windings are classified as____________?
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Answer: C. always 2-layer type
Explanation
Standard direct current machine armature windings are always constructed utilizing a two-layer coil arrangement. This two-layer design places one coil side at the top of a slot and another coil side at the bottom. Arranging windings in two layers ensures complete symmetry, balanced electrical characteristics, and straightforward end-connection assembly. Armature winding configurations dictate how individual copper coils are interconnected inside the slotted iron core. Two-layer windings allow every slot to contain an equal number of top and bottom coil sides for uniform geometry. DC machine commutators require precise lap or wave winding layouts that naturally fit into standard two-layer slot designs.
Sometimes two-layer type is incorrect because standard design practices always mandate two-layer arrangements for DC armatures. Never two-layer type contradicts fundamental electrical machine manufacturing principles which rely entirely on two-layer coils. None of the above is incorrect because the two-layer winding standard is an absolute rule for DC machine armatures.
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- Engineering
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- Electrical Engineering
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- medium
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