1. What is the interrupting medium used in Air Blast Circuit Breaker (ABCB)?
(a). Oil
(b). Water
(c). compressed air
(d). SF6
2. What initiates the release of compressed air into the arc extinction chamber in ABCB?
(a). current flow
(b). voltage drop
(c). tripping mechanism
(d). Magnetic Field
3. How does air blast contribute to arc interruption in ABCB?
(a). by creating a magnetic field
(b). by pushing dynamic contacts together
(c). by carrying away ionized gases
(d). by increasing the arc temperature
4. What happens at the moment of current zero in the process of arc extinction?
(a). the arc has been started
(b). dynamic contacts fall apart
(c). The contact area is filled with fresh air
(d). ionized gases are released
5. What is the purpose of interrupt procedure in ABCB?
(a). to start the arc
(b). To prevent re-attack
(c). To separate dynamic contacts
(d). to carry away ionized gases
6. Which type of ABCB is suitable for high-voltage applications?
(a). Axial Blast Air Circuit Breaker
(b). Radial Blast Air Circuit Breaker
(c). Cross Blast Air Circuit Breaker
(d). All of the above
7. In a cross-blast air circuit breaker, how is the air directed during the arc interruption process?
(a). longitudinally
(b).radius
(c). at right angles to the arc
(d). diagonally
8. What is the benefit of absence of oil in air blast circuit breaker?
(a). fast operation
(b). low maintenance
(c). high sensitivity
(d). none of above
9. Why are air blast circuit breakers considered obsolete in some cases?
(a). lack of efficiency
(b). oil dependence
(c). Rise of modern alternatives like SF6 and vacuum circuit breaker
(d). Inability to handle high currents
10. What is the primary drawback of air blast circuit breakers related to air supply?
(a). high maintenance
(b). Dependence on compressed air
(c). Sensitivity to Circuit Severity
(d). lack of dielectric strength
11. Why do air blast circuit breakers require minimal maintenance compared to oil circuit breakers?
(a). wear and tear reduced
(b). lack of air
(c). low operating voltage
(d). increased sensitivity
12. What is the advantage of high-speed reclosure in air blast circuit breakers?
(a). loss of sensitivity
(b). Quick restoration of normal operation after fault is cleared
(c). long maintenance intervals
(d). increased risk of fire
13. Which technology has gradually become preferred over air blast circuit breakers in modern electrical systems?
(a). oil circuit breaker
(b). vacuum circuit breaker
(c). water circuit breaker
(d). gas circuit breaker
14. Air blast circuit breakers can efficiently switch what types of electrical currents without the need for switching resistance?
(a). high currents
(b). low currents
(c). alternating currents
(d). straight streams
15. In which direction does air flow in an axial blast air circuit breaker?
(a). radius
(b). longitudinally
(c). diagonally
(d). at right angles to the arc
16. What does the air blast carry during the arc interruption process?
(a). fresh air
(b). ionized gases
(c). transfer contacts
(d). Magnetic Field
17. What is the purpose of arc extinction chamber in air blast circuit breakers?
(a). to start the arc
(b). To separate dynamic contacts
(c). to release compressed air
(d). To extinguish the arc faster
18. What is the primary disadvantage of air blast circuit breakers related to circuit severity?
(a). high restricted voltage
(b). low restricted voltage
(c). Inability to handle high currents
(d). excessive maintenance requirements
19. How does the dielectric strength of air contribute to withstand the transient recovery voltage?
(a). decreasing with pressure
(b). increasing with pressure
(c). standing still
(d). by generating heat
20. Which technology has emerged as a modern alternative to air blast circuit breaker?
(a). oil circuit breaker
(b).water circuit breaker
(c). SF6 Circuit Breaker
(d). magnetic circuit breaker
21. What is the primary reason for eliminating the fire hazard in air blast circuit breakers?
(a). lack of oil
(b). high operating voltage
(c). quick response time
(d). Dependence on compressed air
22. Which type of air blast circuit breaker design provides complete isolation without the need for a series isolator?
(a). Axial Blast Air Circuit Breaker
(b). Radial Blast Air Circuit Breaker
(c). Cross Blast Air Circuit Breaker
(d). all of the above
23. What is the primary advantage of the radial blast air circuit breaker design?
(a). efficient switching of small currents
(b). suitable for high voltage
(c). lack of maintenance
(d). Quick restoration of normal operation after fault is cleared
24. What does the absence of oil in an air blast circuit breaker contribute to?
(a). increased risk of fire
(b). lack of maintenance
(c). low operating voltage
(d). Dependence on compressed air
25. What is the main advantage of air blast circuit breakers in terms of response time?
(a). Slow response time
(b). quick response time
(c). constant response time
(d). variable response time