MCQOPTIONS
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This section includes 15 Mcqs, each offering curated multiple-choice questions to sharpen your Electric Drives knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
Calculate the value of Vpeak if crest factor=47 and Vr.m.s=6 V. |
| A. | 282 V |
| B. | 300 V |
| C. | 290 V |
| D. | 286 V |
| Answer» B. 300 V | |
| 2. |
When maximum power loss occurs? |
| A. | Rise time |
| B. | Delay time |
| C. | Spread time |
| D. | Rise time or Delay time |
| Answer» B. Delay time | |
| 3. |
A snubber circuit is used with thyristor in ____________ |
| A. | Parallel |
| B. | Series |
| C. | Anti-parallel |
| D. | Series or Parallel |
| Answer» B. Series | |
| 4. |
Which of the following is used to protect SCR from d(v)/d(t) condition? |
| A. | Capacitor |
| B. | Fuse |
| C. | Snubber circuit |
| D. | Inductor |
| Answer» D. Inductor | |
| 5. |
Which of the following is used to protect SCR from d(i)/d(t) condition? |
| A. | Inductor |
| B. | Capacitor |
| C. | Heat sink |
| D. | Fuse |
| Answer» B. Capacitor | |
| 6. |
Which of the following is used to protect SCR from thermal conditions? |
| A. | Heat sink |
| B. | Voltage clamping device |
| C. | Zener diode |
| D. | Snubber circuit |
| Answer» B. Voltage clamping device | |
| 7. |
Which of the following is used to protect SCR from overcurrent? |
| A. | Heat sink |
| B. | Fuse |
| C. | Snubber circuit |
| D. | Zener diode |
| Answer» C. Snubber circuit | |
| 8. |
If latching current of an SCR is 10 mA then its holding current should be ____________ |
| A. | 5 mA |
| B. | 7 mA |
| C. | 8 mA |
| D. | 4 mA |
| Answer» B. 7 mA | |
| 9. |
If holding current of an SCR is 6 mA then its latching current should be ___________ |
| A. | 4 mA |
| B. | 5 mA |
| C. | 12 mA |
| D. | 6 mA |
| Answer» D. 6 mA | |
| 10. |
Holding current of the SCR is ___________ |
| A. | > than latching current |
| B. | < than latching current |
| C. | = to latching current |
| D. | than latching current |
| Answer» C. = to latching current | |
| 11. |
SCR is a __________ device. |
| A. | Uncontrolled |
| B. | Semi-controlled |
| C. | Fully controlled |
| D. | Voltage |
| Answer» C. Fully controlled | |
| 12. |
For successful commutation circuit turn-off time ______ device turn-off time. |
| A. | < |
| B. | > |
| C. | = |
| D. | ~ |
| Answer» C. = | |
| 13. |
Calculate the value of safety factor using the data: tc=12 msec, tq=6 msec. |
| A. | 4 |
| B. | 2 |
| C. | 3 |
| D. | 6 |
| Answer» C. 3 | |
| 14. |
SCR is a current controlled device. |
| A. | True |
| B. | False |
| Answer» B. False | |
| 15. |
The value of latching current is more than holding current. |
| A. | True |
| B. | False |
| Answer» B. False | |