Question 1 of 18

1. What is the name of the converter?

Metal rectifier

Motor-Generator set

Rotary converter

Mercury arc rectifier

Question 1 of 18

Question 2 of 18

2. Which is the main application of synchronous motor?

AC to DC converter

Paper rolling mills

Power factor correction device

Elevators

Question 2 of 18

Question 3 of 18

3. Which converter is having high efficiency?

Mercury arc rectifier

Rotary converter

Motor generator set

SCR converter

Question 3 of 18

Question 4 of 18

4. Why D.C supply is necessary for synchronous motor operation?

Start the motor initially

Run the motor at synchronous speed

Reduce the losses

Run the motor with over load

Question 4 of 18

Question 5 of 18

5. Why exciter is essential to run a synchronous motor?

Reduce the losses in motor

Run the motor at synchronous speed

Carry more load in motor

Improve the power factor

Question 5 of 18

Question 6 of 18

6. What is the purpose of damper winding in a synchronous motor at starting?

Produces torque and runs near in synchronous speed

Produce a high magnetic-field to maintain a constant speed

Produce high voltage to initiate the rotation

Produce high current to start rotate the motor

Question 6 of 18

Question 7 of 18

7. What is the name of the converter?

Rotary converter

Mercury arc rectifier

Metal rectifier

Silicon controlled rectifier

Question 7 of 18

Question 8 of 18

8. What is the function of damper windings in synchronous motor?

Start the synchronous motor

Maintain constant speed

Maintain power factor

Excite the field winding

Question 8 of 18

Question 9 of 18

9. What is the advantage of motor generator set?

Noiseless

DC output voltage can be easily controlled

High efficiency

Low maintenance required

Question 9 of 18

Question 10 of 18

10. What is the function of inverter?

Convert D.C to A.C

Smoothening A.C sine wave

Convert pulsating DC into pure D.C

Convert A.C to D.C

Question 10 of 18

Question 11 of 18

11. Why the synchronous motor fails to run at synchronous speed?

Short in damper winding

Insufficient excitation

Defective pony motor

Open in damper winding

Question 11 of 18

Question 12 of 18

12. How synchronous motor works as a power factor corrector?

Decreasing the speed of motor

Varying the line voltage

Increasing the speed of motor

Varying the field excitation

Question 12 of 18

Question 13 of 18

13. How the synchronous motor is used as a synchronous condenser?

Varying stator current in motor

Varying stator voltage in motor

Varying the motor load

Varying the rotor excitation

Question 13 of 18

Question 14 of 18

14. Which converting device can be over loaded?

Motor generator set

Rectifier unit

Mercury arc rectifier

Rotary converter

Question 14 of 18

Question 15 of 18

15. Which acts as both inverter and converter?

Metal rectifier

Semi conductor diode

Mercury arc rectifier

Synchronous converter

Question 15 of 18

Question 16 of 18

16. What is the function of the part marked as 'X' of the rotary converter?

Reduces voltage drop

Helps to deliver without noise

Collects the delivered direct current

Converts AC to DC

Question 16 of 18

Question 17 of 18

17. Which application requires only DC?

Electroplating

Operating induction motor

Operating repulsion motor

Stepping up of voltage

Question 17 of 18

Question 18 of 18

18. Why the LED's are avoided as converters in rectifier diodes?

Designed for light emitting

Heavily doped device

Very low power device

Very sensitive to temperature

Question 18 of 18