Circuit breakers are essentially______________?
A. current carrying contacts called electrodes
B. arc extinguishers
C. circuits to break the system
D. transformers to isolate the two systems
E. any of the above
A. current carrying contacts called electrodes
B. arc extinguishers
C. circuits to break the system
D. transformers to isolate the two systems
E. any of the above
A. protect the line
B. open the circuit
C. protect the appliance
D. prevent excessive currents
E. none of the above
A. required to operate the circuit breaker
B. absorbed by the circuit of relay
C. developed by the relay circuit
D. none of the above
A. single phase motors only
B. two phase motors only
C. two single phase motors running in parallel
D. three phase motors
A. Oil circuit breakers
B. Air blast circuit breakers
C. Minimum oil circuit breakers
D. All of the above
A. have low contact resistance
B. be clean and smooth
C. be of sufficient size and proper shape
D. have all above properties
A. Lightning arresters
B. Relays
C. Step-down transformer
D. Switchgear