USCG Exam PracticeElectrical fundamentals — DC/AC, motors, distribution
Which type of DC motor is most appropriate for driving a centrifugal pump where nearly constant speed from no load to full load is required?
- A. Series motor, because it provides the highest starting torque.
- B. Compound motor, because it blends series and shunt characteristics.
- ✓ Shunt motor, because it runs at nearly constant speed across the load range.Correct
- D. Series motor, because its speed is independent of field flux changes.
Why C is correct
NEETS Mod. 5 §2-2 identifies the shunt motor as suited to pumps, fans, and machine tools where steady speed matters, noting it runs at nearly constant speed from no load to full load. The series motor's speed varies widely with load, making it unsuitable for this application.
Cited:NEETS Mod. 5 §2-2