Rotating vs stationary parts – What is the stator? Statement: “The stator is the rotating assembly in a generator or motor.” Determine whether this statement is correct.
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ATrue
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BFalse
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CTrue only for synchronous machines
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DTrue for generators but not for motors
Answer
Correct Answer: False
Explanation
Introduction / Context:Terminology in electric machines is foundational. Confusing stator and rotor leads to errors in analyzing windings, losses, and maintenance procedures. This question checks the correct identification of stationary versus rotating assemblies in motors and generators.
Given Data / Assumptions:
- Applies to AC motors/generators (induction, synchronous) and DC machines.
- Standard construction: one stationary component and one rotating component.
- Focus is purely on definitions, not special configurations.
Concept / Approach:
Stator = stationary part that carries field or armature windings depending on machine type. Rotor = rotating part coupled to mechanical shaft. Therefore, the statement claiming the stator is the rotating assembly is false.
Step-by-Step Solution:
Identify parts: stator (static), rotor (rotating).In induction motors: stator has 3-phase windings; rotor may be squirrel-cage or wound.In synchronous machines: stator typically carries the armature; rotor carries DC field (via slip-rings) or permanent magnets.In DC machines: field/armature placements differ, but stator remains stationary.Verification / Alternative check:
Maintenance and mounting evidence: stator frames are bolted to enclosures; rotors turn within bearings and are balanced to minimize vibration.
Why Other Options Are Wrong:
Any option asserting “True” (with or without qualifiers) contradicts basic machine nomenclature.
Common Pitfalls:
Assuming “stator” relates to “state of motion” ambiguously; remembering: “stator stays,” “rotor rotates.”
Final Answer:
False.