Testing and maintenance of electrical machine MCQ-3

1. Which type of fire extinguisher is used for electrical fire :

(A) Water
(B) Foam
(C) CO2 & dry powder
(D) None of these

2. Maintenance consist of the following action(s)

(A) Replacement of component
(B) Repair of component
(C) Service of component
(D) All of the above

3. Scheduled maintenance is ______ between breakdown maintenance and the preventive maintenance.

(A) Joint
(B) Compromise
(C) Bridge
(D) In

4. Changes are made to the system to reduce the future system failure chances is called :

(A) Preventive maintenance
(B) Corrective maintenance
(C) Adaptive maintenance
(D) Perfective maintenance

5. Corrective maintenance is needed when :

(A) Equipment fails
(B) Equipment produces noise
(C) Equipment is available on minimum cost
(D) All of the above

6. In an induction motor, the short circuit test is performed by

(A) Full load
(B) No load
(C) Block rotor
(D) Open rotor

7. Watt meter reading in no-load test of induction motor gives :

(A) Copper losses in the stator
(B) Friction and winding losses
(C) Sum of (a) and (b)
(D) Total losses in the rotor on no load

8. Noise level test in a transfer is a :

(A) Special test
(B) Routine test
(C) Type test
(D) None of these

9. While conducting short-circuit test on a transformer the following side is short circuited

(A) High voltage side
(B) Low voltage side
(C) Primary side
(D) Secondary side

10. A transformer oil must be free from :

(A) Sludge
(B) Odour
(C) Gases
(D) Moisture

11. The transformer oil should have ______ volatility and ______ viscosity.

(A) Low, low
(B) High, high
(C) Low, high
(D) High, low

12. Sumpner’s test is conducted on transformers to determine

(A) All-day efficiency
(B) Temperature
(C) Stray losses
(D) None of these

13. The dielectric strength of transformer oil is expected to be :

(A) 11 KV
(B) 33 KV
(C) 110 KV
(D) 400 KV

14. To run two alternators in parallel, the dark lamp method test is performed to ensure proper :

(A) Voltage matching
(B) Phase difference matching
(C) Phase sequence matching
(D) Frequency matching

15. Swinburne’s test can be performed at :

(A) Any load
(B) Only no load
(C) Only full load
(D) Only half load

16. Size of foundation for electrical machine depends upon :

(A) Types of foundation
(B) Size of machine
(C) Condition of soil
(D) All of the above

17. Vibration in electrical machine can be prevented :

(A) By making proper ahgnment
(B) By making proper designed foundation
(C) Both (a) and (b)
(D) None of these

18. A universal coupling is used to connect two shafts

(A) Which are not in exact alignment
(B) Which are perfectly aligned
(C) Whose axes intersect at a small angle
(D) Have lateral misalignment

19. Effect of moisture on the insulating materials is to

(A) Decrease dielectric constant
(B) Decrease dielectric strength
(C) Decrease insulation resistance
(D) All of the above

20. The complete circuit diagram of a 3-phase induction motor can be drawn with the help of

(A) Block rotor test alone
(B) Running light and blocked rotor and stator resistance tests
(C) Both Blocked rotor and Running light test
(D) Running light test alone