Which motor type should be selected for driving a load that is nearly zero for part of the cycle and reaches a peak for a short duration______________?
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Answer: C. compound motor
Explanation
Cumulative compound motors combine shunt and series fields to handle severe cyclical load swings. They provide high starting torque while maintaining a stable speed profile under fluctuating loads. This prevents the motor from stalling during peak demands or overspeeding when the load drops. Compound motors feature both shunt and series field windings wound on the same magnetic poles. Cumulative compounding means both magnetic fields aid each other to increase overall flux density. Cyclic loads require motors that can absorb shocks without causing drastic speed fluctuations.
Punch presses, shears, and reciprocating compressors frequently experience intermittent peak mechanical loads. Selecting a compound motor ensures reliable operation in heavy manufacturing workshop environments. Proper motor selection minimizes downtime and protects mechanical gearboxes from excessive shock. Series motors would overspeed dangerously when the load drops to nearly zero during the cycle. Shunt motors lack the high starting torque needed to overcome sudden peak mechanical demands. Stating any motor works ignores the specific stability required for heavy cyclic load profiles.
- Subject
- Engineering
- Category
- Electrical Engineering
- Topic
- —
- Difficulty
- medium
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