MCQOPTIONS
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MCQOPTIONS
This section includes 7 Mcqs, each offering curated multiple-choice questions to sharpen your Dc Machines knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
Four-point starter is used when ______________ |
| A. | Motor field current is varied in narrow range |
| B. | Motor speed is varied in small range |
| C. | Motor field current is varied over wide range |
| D. | Can be used anywhere |
| Answer» D. Can be used anywhere | |
| 2. |
γ is given as 1.585. Resistance at maximum allowable current is given equal to 4 Ω, what is the 5th step resistance? |
| A. | 0.235 |
| B. | 0.370 |
| C. | 1.476 |
| D. | 2 |
| Answer» B. 0.370 | |
| 3. |
A starter is required for a 220-V shunt motor. The maximum allowable current is 55 A and the minimum current is about 35 A. The armature resistance of the motor is 0.4 Ω. What will be the number of sections of starter resistance required? |
| A. | 5 |
| B. | 4 |
| C. | 6 |
| D. | 8 |
| Answer» D. 8 | |
| 4. |
In shunt and compound motor starting the shunt field should be made on with full starting resistance in ____________ |
| A. | Series with field |
| B. | Parallel with field |
| C. | Series with armature |
| D. | Parallel with armature |
| Answer» D. Parallel with armature | |
| 5. |
In a manual shunt motor starter relay positions are ________________________ |
| A. | Over load relay is connected in series and no volt relay in parallel with the load |
| B. | Over load relay is connected in parallel and no volt relay in series with the load |
| C. | Over load relay and no volt relay are both connected in series with the load |
| D. | Over load relay and no volt relay are both connected in parallel with the load |
| Answer» B. Over load relay is connected in parallel and no volt relay in series with the load | |
| 6. |
The starting resistance of a DC shunt motor is generally ______ |
| A. | low |
| B. | Around 0.5 kΩ |
| C. | Around 5 kΩ |
| D. | Infinitely large |
| Answer» B. Around 0.5 kΩ | |
| 7. |
A three-point starter is used for _________ |
| A. | Shunt motors |
| B. | Shunt as well as compound motors |
| C. | Shunt, compound and series motors |
| D. | Not for DC motors |
| Answer» C. Shunt, compound and series motors | |