1. Over voltage protection is recommended for ?

gas turbine generators

hydro-electric generators

steam turbine generators

all of the above

Answer: all of the above

Explanation:


2. Air blast circuit breakers for 400 kV power system are designed to operate ln ?

0.5 sec

0.1 sec

100 micro-second

milli-second

Answer: milli-second

Explanation:


3. The material used for fuse must have ?

high melting point and low specific resistance

low melting point and any specific resistance

low melting point and low specific resistance

low melting point and high specific resistance

Answer: low melting point and high specific resistance

Explanation:


4. The steady state stability of the power system can be increased by ?

using machines of high impedance

connecting lines in parallel

reducing the excitation of machines

connecting lines in series

Answer: connecting lines in parallel

Explanation:


5. An isolator is installed ?

always independent of the position of circuit breaker

generally on both sides of a circuit breaker

as a substitute for circuit breaker

to operate the relay of circuit breaker

Answer: generally on both sides of a circuit breaker

Explanation:


6. A switchgear is device used for ?

switching and controlling an electrical circuit

switching, controlling and protecting the electrical circuit and equipment

interrupting an electrical circuit

switching an electrical circuit

Answer: switching, controlling and protecting the electrical circuit and equipment

Explanation:


7. The fuse wire, in D.C. circuits, is inserted in ?

Positive circuit only

negative circuit only

both (a) and (b)

either (a) and (b)

Answer: both (a) and (b)

Explanation:


8. A circuit breaker, under normal conditions, should be inspected ?

every week

once in 6 months or 12 months

every day

every month

Answer: once in 6 months or 12 months

Explanation:


9. The total time for high speed breakers in nearly ?

five cycles

one cycle

half cycle

few cycles

Answer: half cycle

Explanation:


10. ...... gives rise to symmetrical fault ?

Three-phase short-circuit

Phase-to-phase

double phase to ground

Single phase to ground

Answer: Three-phase short-circuit

Explanation: