DC motors are stopped by opening line switches and not by forcing the handle of the motor starter back to OFF position. This is due to occurance of

Electrical Machines
DC motors are stopped by opening line switches and not by forcing the handle of the motor starter back to OFF position. This is due to occurance of

Both of above.

None of these.

Heavy sparking at brushes.

Heavy sparking at the first stud of starting resistance steps.

Both of above.

None of these.

Heavy sparking at brushes.

Heavy sparking at the first stud of starting resistance steps.

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Electrical Machines
If the applied voltage of a DC motor is 230 V, then back emf, for maximum power developed is

230 V.

460 V.

115 V.

200 V.

230 V.

460 V.

115 V.

200 V.

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Electrical Machines
Which of the following is done in speed control of DC motor by field flux control?

Inserting an additional resistance in the armature circuit.

Inserting resistance to armature circuit and field circuit.

Any of above.

Inserting an additional resistance in the field circuit.

Inserting an additional resistance in the armature circuit.

Inserting resistance to armature circuit and field circuit.

Any of above.

Inserting an additional resistance in the field circuit.

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Electrical Machines
Alternator operates on the principle of

electromagnetic induction.

mutual induction.

self induction.

self or mutual induction.

electromagnetic induction.

mutual induction.

self induction.

self or mutual induction.

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Electrical Machines
A commutator in DC machines can 1. provide half-wave rectification 2. Provide full-wave rectification 3. convert ac to dc 4. Convert dc to ac 5. provide controlled full-wave rectification From these, the correct answer is

2, 3, 4

2, 3 ,5

2, 3, 4, 5

1, 2, 3

2, 3, 4

2, 3 ,5

2, 3, 4, 5

1, 2, 3

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Electrical Machines
In a 12 pole triplex lap wound DC armature, each conductor can carry current of 100 A. The rated current of this armature is

600 A.

3600 A.

2400 A.

1200 A.

600 A.

3600 A.

2400 A.

1200 A.

ANSWER DOWNLOAD EXAMIANS APP

Electrical Machines

Electrical Machines DC motors are stopped by opening line switches and not by forcing the handle of the motor starter back to OFF position. This is due to occurance of

Electrical Machines If the applied voltage of a DC motor is 230 V, then back emf, for maximum power developed is

Electrical Machines Which of the following is done in speed control of DC motor by field flux control?

Electrical Machines Alternator operates on the principle of

Electrical Machines A commutator in DC machines can 1. provide half-wave rectification 2. Provide full-wave rectification 3. convert ac to dc 4. Convert dc to ac 5. provide controlled full-wave rectification From these, the correct answer is

Electrical Machines In a 12 pole triplex lap wound DC armature, each conductor can carry current of 100 A. The rated current of this armature is

Electrical Machines
DC motors are stopped by opening line switches and not by forcing the handle of the motor starter back to OFF position. This is due to occurance of

Electrical Machines
If the applied voltage of a DC motor is 230 V, then back emf, for maximum power developed is

Electrical Machines
Which of the following is done in speed control of DC motor by field flux control?

Electrical Machines
Alternator operates on the principle of

Electrical Machines
A commutator in DC machines can 1. provide half-wave rectification 2. Provide full-wave rectification 3. convert ac to dc 4. Convert dc to ac 5. provide controlled full-wave rectification From these, the correct answer is

Electrical Machines
In a 12 pole triplex lap wound DC armature, each conductor can carry current of 100 A. The rated current of this armature is