The direction of rotation of a 3 - ÃŽÂ¦ induction motor is clockwise when it is supplied with 3 - ÃŽÂ¦ sinusoidal voltage having phase sequence A - B - C. For counterclockwise rotation of motor, the phase sequence of the supply should be

Electrical Machines
The direction of rotation of a 3 - ÃŽÂ¦ induction motor is clockwise when it is supplied with 3 - ÃŽÂ¦ sinusoidal voltage having phase sequence A - B - C. For counterclockwise rotation of motor, the phase sequence of the supply should be

B - C - A.

B - C - A or C - A - B.

C - A - B.

A - C - B.

B - C - A.

B - C - A or C - A - B.

C - A - B.

A - C - B.

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Electrical Machines
In DC generators, the cause of rapid brush wear may be

rough commutator surface.

any of above.

imperfect contact.

severe sparking.

rough commutator surface.

any of above.

imperfect contact.

severe sparking.

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Electrical Machines
If the armature electric current is increased to double its previous value, and the time of commutation is halved, how will the reactance voltage vary?

It will remain the same.

It will becomes four times.

It will be halved.

It will be doubled.

It will remain the same.

It will becomes four times.

It will be halved.

It will be doubled.

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Electrical Machines
A small air gap in poly phase induction motor helps to

reduce chance of crawling.

reduce magnetizing current.

reduce chance of cogging.

increase starting torque.

reduce chance of crawling.

reduce magnetizing current.

reduce chance of cogging.

increase starting torque.

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Electrical Machines
A 4 pole 50 Hz induction motor is running at 1470 rpm. The frequency of rotor current is

50 Hz

0 Hz

5 Hz

1 Hz

50 Hz

0 Hz

5 Hz

1 Hz

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Electrical Machines
In a DC machine the armature mmf is

rotating with respect to field poles.

rotating with respect to field poles as well as armature.

stationary with respect to armature.

stationary with respect to field poles.

rotating with respect to field poles.

rotating with respect to field poles as well as armature.

stationary with respect to armature.

stationary with respect to field poles.

ANSWER DOWNLOAD EXAMIANS APP

Electrical Machines

Electrical Machines The direction of rotation of a 3 - ÃŽÂ¦ induction motor is clockwise when it is supplied with 3 - ÃŽÂ¦ sinusoidal voltage having phase sequence A - B - C. For counterclockwise rotation of motor, the phase sequence of the supply should be

Electrical Machines In DC generators, the cause of rapid brush wear may be

Electrical Machines If the armature electric current is increased to double its previous value, and the time of commutation is halved, how will the reactance voltage vary?

Electrical Machines A small air gap in poly phase induction motor helps to

Electrical Machines A 4 pole 50 Hz induction motor is running at 1470 rpm. The frequency of rotor current is

Electrical Machines In a DC machine the armature mmf is

Electrical Machines
The direction of rotation of a 3 - ÃŽÂ¦ induction motor is clockwise when it is supplied with 3 - ÃŽÂ¦ sinusoidal voltage having phase sequence A - B - C. For counterclockwise rotation of motor, the phase sequence of the supply should be

Electrical Machines
In DC generators, the cause of rapid brush wear may be

Electrical Machines
If the armature electric current is increased to double its previous value, and the time of commutation is halved, how will the reactance voltage vary?

Electrical Machines
A small air gap in poly phase induction motor helps to

Electrical Machines
A 4 pole 50 Hz induction motor is running at 1470 rpm. The frequency of rotor current is

Electrical Machines
In a DC machine the armature mmf is