How many types of DC motors are there?

How many types of DC motors are there?
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1 Answer

Answer :

DC shunt motor: shunt motor speed varies slightly from no load to full load.

DC series motor: series motor speed varies greatly as load changes.

DC compound motor: the compound motor contains both a shunt field and a series field and therefore has characteristics between the shunt and the series motors. This motor has the good starting torque characteristics provided by the series field, while the shunt field provides for a relatively constant speed. 
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Description : Which of the following is a characteristic of fractional horsepower repulsion start motors? A. They start with a rotating stator field. B. The short circuiting ring is removed from the commutator while ... brushes are removed from the commutator while starting. D. They have a low starting torque.

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Last Answer : Answer: A

If a unloaded shunt motor's field were weakened by rheostat resistance or by an open circuit, the motor would _________. A. overspeed due to reduced CEMF B. stop because of low flux C. continue to run at base speed D. slow down and overheat

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All of the following items can be used in the maintenance of a D.C. propulsion motor's commutator EXCEPT _______________. A. a canvas wiper B. safety solvent C. abrasive dressing stones D. sandpaper

Description : All of the following items can be used in the maintenance of a D.C. propulsion motor's commutator EXCEPT _______________. A. a canvas wiper B. safety solvent C. abrasive dressing stones D. sandpaper

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Last Answer : Answer: C

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Last Answer : Answer: A

As shown in the illustration, the D.C. motor's direction of rotation in changed by changing the _________________. EL-0101 A. polarity of the generator field B. direction of three-phase motor rotation C. direction of generator rotation D. polarity of the motor field

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Last Answer : Answer: A

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Last Answer : Answer: A