Number of commutator bars for a 4-pole, 2-layer, DC lap winding with 24 slots and one conductor per layer is

Number of commutator bars for a 4-pole, 2-layer, DC lap winding with 24 slots and one conductor per layer is

(A) 48 (B) 24 (C) 192 (D) 96
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Answer :

Number of commutator bars for a 4-pole, 2-layer, DC lap winding with 24 slots and one conductor per layer is 24

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In lap winding, the number of brushes is always?

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As shown in the illustration, part 'X' of the diagram is known as a/an _____________. EL-0052 A. commutator B. interpole C. starting pole D. auxiliary pole

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Uneven wear of the commutator surface on a direct current propulsion motor can be caused by _____________. A. rapid change in load B. excessive operation at light load C. incorrect brush staggering D. unequal pole spacing

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Brushes in a generator must be positioned in the neutral plane to avoid sparking between the brushes and the _____________. A. yoke B. armature windings C. field pole windings D. commutator

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Last Answer : Answer: D

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Description : Lap splicing are not usually allowed for bars more than [ A ] 25 mm [ B ] 32 mm [ C ] 36 mm [ D ] None of the above

Last Answer : [ C ] 36 mm

Lap splicing are not usually allowed for bars more than [ A ] 25 mm [ B ] 32 mm [ C ] 36 mm [ D ] None of the above

Description : Lap splicing are not usually allowed for bars more than [ A ] 25 mm [ B ] 32 mm [ C ] 36 mm [ D ] None of the above

Last Answer : [ C ] 36 mm

Lap winding is composed of?

Last Answer : Lap winding is composed of any even number of conductors.

In D.C. generators, lap winding is used for?

Last Answer : In D.C. generators, lap winding is used for low voltage, high current.

In the case of lap winding resultant pitch is?

Last Answer : In the case of lap winding resultant pitch is difference of front and back pitches.

In a D.C. machine, how are the commutating pole winding connected?

Last Answer : In series with the shunt winding

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Description : The speed of a squirrel-cage induction motor is determined by the ____________. A. diameter of the stator B. number of stator poles C. rotor winding resistance D. rotor conducting bars resistance

Last Answer : Answer: B

Basic electrical motor action depends on _______________. A. a conductor rotated within a magnetic field B. a current carrying conductor placed in a magnetic field C. the relative force of the commutator and commutating poles D. the relative force of the armature and interpoles

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Which of the listed colors properly describes a DC motor commutator when correct commutation is taking place? A. Shiny blue B. Burnished green C. Brick red D. Chocolate brown

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