1. What is the primary function of insulating oil in oil circuit breakers?
(a). generate electricity
(b). extinguishing the arc during a fault
(c). Increase circuit current
(d). Increase thermal conductivity
2. What by-products are produced when an arc forms under oil in oil circuit breakers?
(a). Nitrogen gas
(b). Hydrogen gas and other by-products
(c). Oxygen gas
(d). carbon dioxide
3. What role does hydrogen gas play in interrupting the circuit current in oil circuit breakers?
(a). Increases arch formation
(b). Provides insulation
(c). Cools the system faster
(d). Increases oil decomposition
4. What is the main advantage of oil as an arc quenching medium in circuit breakers?
(a). Low diffusion rate of hydrogen
(b). flammable nature
(c). Efficient absorption of arc energy
(d). Lack of dielectric strength
5. What is a significant disadvantage of using oil as an arc quenching medium?
(a). Low dielectric strength
(b). non flammable nature
(c). Fire hazard
(d). Inefficient cooling surface
6. What is the purpose of desalination process in oil circuit breakers?
(a). Decrease dielectric strength
(b). produce hydrogen gas
(c). remove byproducts produced during the arc extinction
(d). increase oil decomposition
7. Which type of oil circuit breaker contains a sufficient amount of oil and is classified into dead tank type and live tank type?
(a). Plain Break Oil Circuit Breaker
(b). low oil circuit breaker
(c). Bulk Oil Circuit Breaker
(d). Arc Control Oil Circuit Breaker
8. What challenges do low oil circuit breakers face despite the benefits of low oil and space requirements?
(a). Increase in carbonization and rapid loss of dielectric strength.
(b). Reduction in carbonization and increase in dielectric strength
(c). Improved fire resistance
(d). Advanced Arc Control
9. Which type of oil circuit breaker is known for relatively long and inconsistent arcing times due to the absence of special arc control devices?
(a). Arc Control Oil Circuit Breaker
(b). low oil circuit breaker
(c). Plain Break Oil Circuit Breaker
(d). Bulk Oil Circuit Breaker
10. What is the main purpose of externally generated pressure in arc control oil circuit breakers?
(a). increased risk of fire
(b). Improve arc control stability
(c). Reduce oil decomposition
(d). Increase thermal conductivity
11. Why do low oil circuit breakers face challenges such as increased carbonization?
(a). Lack of dielectric strength
(b). Oil and space requirements reduced
(c). Use of excessive oil
(d). Minimum oil use
12. How often is routine maintenance recommended for oil circuit breakers?
(a). monthly
(b). annual
(c). Every 3 to 6 months
(d). Only when there is a mistake
13. What tasks are involved in routine maintenance of oil circuit breakers?
(a). Checking and changing contacts and oil
(b). monitoring voltage fluctuations
(c). Test for arc resistance
(d). Adjustment of circuit current
14. What is the potential risk associated with the flammable nature of oil in oil circuit breakers?
(a). Increased dielectric strength
(b). Formation of explosive mixture with air
(c). better insulation
(d). Decrease in arch formation.
15. In oil circuit breakers, what is the effect of rapid cooling due to high diffusion rate of hydrogen?
(a). Increased risk of fire
(b). better arc stability
(c). Decrease in dielectric strength
(d). Advanced oil decomposition
16. Which type of oil circuit breaker is known to be constructed directly without any special arc control device?
(a). Arc Control Oil Circuit Breaker
(b). low oil circuit breaker
(c). Plain Break Oil Circuit Breaker
(d). Bulk Oil Circuit Breaker
17. What is the primary purpose of the high dielectric strength of oil in oil circuit breakers?
(a). increased risk of fire
(b). Provide insulation after arc extinction
(c). Generate explosive mixture with air
(d). increase arch formation
18. How does decomposition of oil in oil circuit breakers affect pollution levels?
(a). Reduces pollution
(b). Increases pollution
(c). No effect on pollution
(d). Increases dielectric strength
19. What is the role of the tank in a live tank type bulk oil circuit breaker?
(a). Increase dielectric strength
(b). insulate the tank from ground
(c). increased risk of fire
(d). Provide a platform for arch formation
20. Which type of oil circuit breaker faces challenges like increasing carbonization and rapid decline in dielectric strength?
(a). Plain Break Oil Circuit Breaker
(b). Arc Control Oil Circuit Breaker
(c). Bulk Oil Circuit Breaker
(d). Low Oil Circuit Breaker
Answer: D
21. What challenges do bulk oil circuit breakers face in terms of maintenance due to their design?
(a). Minimum Maintenance Requirements
(b). complex routine maintenance
(c). Decrease in dielectric strength
(d). increased risk of fire
22. What is the purpose of desalination process in oil circuit breakers?
(a). Generate explosive mixture with air
(b). Remove byproducts produced during arc extinction
(c). increased risk of fire
(d). Increase arc control
23. What role does the high thermal conductivity of hydrogen play in the oil circuit breaker desalination process?
(a). increased risk of fire
(b). cool down the system faster
(c). Increase dielectric strength
(d). reduce pollution
24. Which type of oil circuit breaker has high risk of fire?
(a). bulk oil circuit breaker
(b). Arc Control Oil Circuit Breaker
(c). Low Oil Circuit Breaker
(d). Plain Break Oil Circuit Breaker
25. Why is regular inspection of oil circuit breakers important for their maintenance?
(a). Increase dielectric strength
(b). reduce fire risk
(c). Ensure proper functionality over time
(d). reduce oil decomposition