Power System Protection MCQs - Quiz 2 (Circuit Breakers)
Wednesday, March 14, 2018
CIRCUIT BREAKERS
1. In air circuit breakers ___ is used to suppress the arc.
A) Water
B) Air
C) Oil
D) Nitrogen
2. In oil circuit breakers the function of oil is:
A) Cooling
B) Insulation
C) Rust protection
D) Arc suppression
3. The contacts in circuit breakers are made of:
A) Carbon
B) Copper alloy
C) Tungsten
D) Cast iron
4. Which of the following is a routine test in circuit breakers?
A) Contact resistance test
B) Insulation resistance test
C) Timing tests
D) All of above
5. ___ is the voltage that appears across the contacts of the circuit breaker after arc extinction.
A) Surge
B) Recovery
C) Nominal
D) Operating
6. SF6 gas is:
A) Colorless
B) Odorless
C) Not inlfamable
D) All of above
7. The power for shunt trip circuit breaker comes from:
A) Within the breaker
B) External source
C) Either of A or B
8. According to IEC high voltage (HV) circuit breakers are used for ___ voltages.
A) 1 kV or higher
B) 33 kV or higher
C) 72.5 kV or higher
D) None of above
9. Circuit breaker are actuated through ___ mechanism.
A) Hydraulic
B) Pneumatic
C) Spring
D) All of above
10. The trip action in a magnetic circuit breaker is:
A) Instantaneous
B) Delayed
C) Both A & B
1. In air circuit breakers ___ is used to suppress the arc.
A) Water
B) Air
C) Oil
D) Nitrogen
2. In oil circuit breakers the function of oil is:
A) Cooling
B) Insulation
C) Rust protection
D) Arc suppression
3. The contacts in circuit breakers are made of:
A) Carbon
B) Copper alloy
C) Tungsten
D) Cast iron
4. Which of the following is a routine test in circuit breakers?
A) Contact resistance test
B) Insulation resistance test
C) Timing tests
D) All of above
5. ___ is the voltage that appears across the contacts of the circuit breaker after arc extinction.
A) Surge
B) Recovery
C) Nominal
D) Operating
6. SF6 gas is:
A) Colorless
B) Odorless
C) Not inlfamable
D) All of above
7. The power for shunt trip circuit breaker comes from:
A) Within the breaker
B) External source
C) Either of A or B
8. According to IEC high voltage (HV) circuit breakers are used for ___ voltages.
A) 1 kV or higher
B) 33 kV or higher
C) 72.5 kV or higher
D) None of above
9. Circuit breaker are actuated through ___ mechanism.
A) Hydraulic
B) Pneumatic
C) Spring
D) All of above
10. The trip action in a magnetic circuit breaker is:
A) Instantaneous
B) Delayed
C) Both A & B
