A. zero current
B. maximum current
C. minimum voltage
D. maximum voltage
Related Mcqs:
- Which of the following medium is employed for extinction of arc in air circuit breaker?
A. Water
B. Oil
C. Air
D. SF6 - The arc voltage produced in A.C. circuit breaker is always_____________?
A. in phase with the arc current
B. lagging the arc current by 90″
C. leading the arc current by 90°
D. none of the above - Thermal circuit breaker has____________?
A. delayed trip action
B. instantaneous trip action
C. both of the above
D. none of the above - Magnetic circuit breaker has ___________ trip action
A. delayed
B. instantaneous
C. both of the above
D. none of the above - The arcing contacts in a circuit breaker are made of______________?
A. copper tungsten alloy
B. porcelain
C. electrolytic copper
D. aluminium alloy - Air blast circuit breaker is used for_____________?
A. over currents
B. short duty
C. intermittant duty
D. repeated duty - The voltage appearing across the contacts after opening of the circuit breaker is called__________voltage
A. recovery
B. surge
C. operating
D. arc
E. none of the above - In a circuit breaker the basic problem is to________________?
A. maintain the arc
B. extinguish the arc
C. transmit large power
D. emit the ionizing electrons - Ionization in circuit breaker is facilitated by___________?
A. high temperature
B. increase of mean free path
C. increasing field strength
D. all of the above - The information to the circuit breaker under fault conditions is provided by____________?
A. relay
B. rewirable fuse
C. H.R.C. only
D. all of the above
