1. What is the primary medium used in SF6 circuit breakers to extinguish electrical arc?
(a). Oil
(b). Air
(c). Vacuum
(d). SF6
2. What differentiates SF6 circuit breakers from traditional alternatives such as oil, air or vacuum circuit breakers?
(a). Slow arc extinction
(b). Slow recovery voltage build-up
(c). Rapid arc extinction
(d). Low dielectric strength
3. What is the color of SF6 gas?
(a). Green
(b). Colorless
(c). Yellow
(d). Blue
4. How does SF6 gas remove heat during arcing period in circuit breaker?
(a). Only radial dissipation
(b). Axial convection only
(c). Axial convection and radial dissipation
(d).Tthrough chemical reactions
5. Which principle is employed in SF6 circuit breakers where gas is forced through a converging-diverging nozzle to extinguish the arc?
(a). Venting principle
(b). Puffer piston principle
(c). Thermal expansion principle
(d). Pressure relief principle
6. What are the physical and chemical properties of SF6 gas?
(a). Yellow, poisonous and flammable
(b). Colorless, non-toxic and non-flammable
(c). Green, poisonous and flammable
(d). Blue, non-toxic and inflammable
7. How does SF6 gas contribute to effective cooling of current carrying parts in circuit breakers?
(a). High thermal expansion
(b). Low thermal conductivity
(c). High thermal conductivity
(d). Low thermal expansion
8. What is the dielectric strength of SF6 gas, which makes it effective for insulation in switchgear?
(a). Low dielectric strength
(b). Medium dielectric strength
(c). High dielectric strength
(d). Variable dielectric strength
9. What happens to SF6 gas after the source of spark is removed in terms of recombination?
(a). Slow recombination
(b). No recombination
(c). Rapid recombination
(c). Variable recombination
10. How do SF6 circuit breakers excel in arc extinction?
(a). Slow dielectric strength recovery
(b). Rapid dielectric strength recovery
(c). No dielectric strength recovery
(d). Variable dielectric strength recovery
11. What is the primary component of the interrupter unit in an SF6 circuit breaker?
(a). Dynamic and static contact
(b). Gas system
(c). Arcing probe
(d). Clogging the nozzle
12. What is the purpose of the gas system in an SF6 circuit breaker?
(a). To generate electrical power
(b).To cool the arc
(c). For repair and recovery of SF6 gas after each operation.
(d). Creating a vacuum
13. How do SF6 circuit breakers contribute to reducing power draw?
(a). By increasing the power output
(b). By maintaining the same electrical clearance
(c). By eliminating power drain
(d). By reducing power drain
14. What is the typical maintenance interval for SF6 circuit breakers?
(a). 1-3 years
(b). 4-10 years
(c). 11-15 years
(d). No specific maintenance interval
15. What is one of the challenges faced by SF6 circuit breakers with respect to gas leakage?
(a). No gas leakage
(b). Gas leakage is occurring due to sealing problem.
(c). Controlled gas leakage
(d). Gas leakage due to overheating
16. What risks are associated with SF6 gas leakage?
(a). Fire hazard
(b). Risk of explosion
(c). Danger of suffocation
(d). Risk of inhaling poisonous gas
17. Despite being non-toxic, what is the potential harmful effect associated with SF6 gas?
(a). Skin irritation
(b). Toxicity of arcade SF6 gas.
(c). Eye irritation
(d). Respiratory problems
18. What is the primary advantage of SF6 gas in terms of its dielectric strength?
(a). Low dielectric strength
(b). Variable dielectric strength
(c). High dielectric strength
(d). No dielectric strength
19. How does SF6 gas contribute to noiseless operation in circuit breakers?
(a). By producing loud sounds
(b). By reducing contact erosion.
(c). By causing vibrations
(d). By generating heat
20. What is the role of puffer piston principle in SF6 circuit breaker?
(a). To create a vacuum
(b). Forcing gas through the nozzle to extinguish the arc
(c). Generating electrical power
(d). To cool the arc
21. What is the key property of SF6 gas that enables effective insulation in switchgear?
(a). High flammability
(b). High toxicity
(c). High dielectric strength
(d). Low thermal conductivity
22. How does SF6 gas contribute to effective cooling of current carrying parts in circuit breakers?
(a). High thermal expansion
(b). Low thermal conductivity
(c). High thermal conductivity
(d). Low thermal expansion
23. What is the primary component of the gas system in an SF6 circuit breaker?
(a). Dynamic and static contact
(b). Interpreter Unit
(c). Repair and Recovery Unit
(d). Arcing probe
24. What differentiates SF6 circuit breakers from conventional options in terms of their size?
(a). Big size
(b). Small size
(c). Constant size
(d). Variable size
25. What is the primary challenge related to SF6 circuit breakers mentioned in the article?
(a). Limited versatility
(b). Excessive maintenance requirements
(c). Sealing problem due to gas leakage
(d). Inefficient arc extinction