Question 1

The inverse definite mean time relays are used for over current and earth fault protection of transformer against

Accepted Answer

A) heavy loads 
B) internal short-circuits 
C) external short-circuits 
D) all of the above 
A) heavy loads 
B) internal short-circuits 
C) external short-circuits 
D) all of the above B

Question 2

For cost and safety, the outdoor substations are installed for voltages above

Accepted Answer

A) 11 kV 
B) 33 kV 
C) 60kV 
D) 110kV 
A) 11 kV 
B) 33 kV 
C) 60kV 
D) 110kV B

Question 3

The relay with inverse time characteristic will operate within

Accepted Answer

A) 1.5 sec 
B) 5 to 10 sec 
C) 5 to 20 sec 
D) 20 to 30 sec 
A) 1.5 sec 
B) 5 to 10 sec 
C) 5 to 20 sec 
D) 20 to 30 sec B

Question 4

For which of the following protection from negative sequence currents is provided ?

Accepted Answer

A) Generators 
B) Motors 
C) Transmission line 
D) Transformers 
A) Generators 
B) Motors 
C) Transmission line 
D) Transformers

Question 5

Discrimination between main and back up protection is provided by the use of relays which are

Accepted Answer

A) fact 
B) sensitive 
C) slow 
D) none of the above 
A) fact 
B) sensitive 
C) slow 
D) none of the above

Question 6

The short circuit in any winding of the transformer is the result of

Accepted Answer

A) mechanical vibration 
B) insulation failure 
C) loose connection 
D) impulse voltage 
A) mechanical vibration 
B) insulation failure 
C) loose connection 
D) impulse voltage

Question 7

Which of the following devices will receive voltage surge first travelling on the transmission line ?

Accepted Answer

A) Lightning arresters 
B) Relays 
C) Step-down transformer 
D) Switchgear 
A) Lightning arresters 
B) Relays 
C) Step-down transformer 
D) Switchgear

Question 8

relay is preferred for phase fault on short transmission line.

Accepted Answer

A) Induction type 
B) Reactance 
C) Impedance 
D) None of the above 
A) Induction type 
B) Reactance 
C) Impedance 
D) None of the above

Question 9

To reduce short circuit fault currents are used.

Accepted Answer

A) reactors 
B) resistors 
C) capacitors 
D) none of the above 
A) reactors 
B) resistors 
C) capacitors 
D) none of the above

Question 10

Which of the following statements is incorrect ?

Accepted Answer

A) Lightning arrestors are used before the switchgear 
B) Shunt reactors are used as compensation reactors 
C) The peak short current is (1.8 xV2) times the A.C. component 
D) The MVA at fault is equal to base MVA divided by per unit equivalent fault 
A) Lightning arrestors are used before the switchgear 
B) Shunt reactors are used as compensation reactors 
C) The peak short current is (1.8 xV2) times the A.C. component 
D) The MVA at fault is equal to base MVA divided by per unit equivalent fault

Question 11

Which of the following circuit breakers has high reliability and minimum maintenance ?

Accepted Answer

A) Air blast circuit breakers 
B) Circuit breaker with SF6 gas 
C) Vacuum circuit breakers 
D) Oil circuit breakers 
A) Air blast circuit breakers 
B) Circuit breaker with SF6 gas 
C) Vacuum circuit breakers 
D) Oil circuit breakers

Question 12

A.C. network analyser is used to solve problems of

Accepted Answer

A) load flow 
B) load flow and short-circuit 
C) load flow and stability 
D) load flow, short-circuit and stability 
A) load flow 
B) load flow and short-circuit 
C) load flow and stability 
D) load flow, short-circuit and stability

Question 13

Arc in a circuit breaker is interrupted at

Accepted Answer

A) zero current 
B) maximum current 
C) minimum voltage 
D) maximum voltage 
A) zero current 
B) maximum current 
C) minimum voltage 
D) maximum voltage

Question 14

relays are used for phase faults on long line.

Accepted Answer

A) Impedance 
B) Reactance 
C) Either of the above 
D) None of the above 
A) Impedance 
B) Reactance 
C) Either of the above 
D) None of the above

Question 15

A _______ is used to measure the stator % winding temperature of the generator.

Accepted Answer

A) thermocouple 
B) pyrometer 
C) resistance thermometer 
D) thermometer 
A) thermocouple 
B) pyrometer 
C) resistance thermometer 
D) thermometer

Question 16

Distance relays are generally

Accepted Answer

A) split-phase relays 
B) reactance relays 
C) impedance relays 
D) none of the above 
A) split-phase relays 
B) reactance relays 
C) impedance relays 
D) none of the above

Question 17

Induction cup relay is operated due to changes in

Accepted Answer

A) current 
B) voltage 
C) impedance 
D) all of the above 
A) current 
B) voltage 
C) impedance 
D) all of the above

Question 18

What will be the reflection co-efficient of the wave of load connected to transmission line if surge impedance of the line is equal to load ?

Accepted Answer

A) Zero 
B) Unity 
C) Infinity 
D) None of the above 
A) Zero 
B) Unity 
C) Infinity 
D) None of the above

Question 19

Which of the following statements is incorrect?

Accepted Answer

A) Station batteries are used to operate relay only 
B) The lightning arresters are basically surge diverters 
C) An impedance relay has maximum fault current when fault occurs near the relay 
D) A high speed relay has an operation of 1 to 2 cycles 
A) Station batteries are used to operate relay only 
B) The lightning arresters are basically surge diverters 
C) An impedance relay has maximum fault current when fault occurs near the relay 
D) A high speed relay has an operation of 1 to 2 cycles

Question 20

The single phasing relays are used for the protection of

Accepted Answer

A) single phase motors only 
B) two phase motors only 
C) two single phase motors running in parallel 
D) three phase motors 
A) single phase motors only 
B) two phase motors only 
C) two single phase motors running in parallel 
D) three phase motors

The inverse definite mean time relays are used for over current and earth fault protection of transformer against

For cost and safety, the outdoor substations are installed for voltages above

The relay with inverse time characteristic will operate within

For which of the following protection from negative sequence currents is provided ?

Discrimination between main and back up protection is provided by the use of relays which are

The short circuit in any winding of the transformer is the result of

Which of the following devices will receive voltage surge first travelling on the transmission line ?

relay is preferred for phase fault on short transmission line.

To reduce short circuit fault currents are used.

Which of the following statements is incorrect ?

Which of the following circuit breakers has high reliability and minimum maintenance ?

A.C. network analyser is used to solve problems of

Arc in a circuit breaker is interrupted at

relays are used for phase faults on long line.

A _______ is used to measure the stator % winding temperature of the generator.

Distance relays are generally

Induction cup relay is operated due to changes in

What will be the reflection co-efficient of the wave of load connected to transmission line if surge impedance of the line is equal to load ?

Which of the following statements is incorrect?

The single phasing relays are used for the protection of

Electrical Protection and Circuit Breakers

Electrical Protection and Transmission Line Characteristics

Electrical Protection and Safety: Part A

Electrical Protection and Safety: Part B

Protective Relays and Circuit Breakers for Electrical Systems

Circuit Breakers and Fuses

Electric Arc and Circuit Breaker Protection

Electrical Components and Circuit Breakers

Electrical Protection and Switchgear

Relaying Schemes and Techniques for Electrical Equipment Protection

Understanding Relays for Power System Protection

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Exam 3: Power System Protection and Equipment

The inverse definite mean time relays are used for over current and earth fault protection of transformer against

For cost and safety, the outdoor substations are installed for voltages above

The relay with inverse time characteristic will operate within

For which of the following protection from negative sequence currents is provided ?

Discrimination between main and back up protection is provided by the use of relays which are

The short circuit in any winding of the transformer is the result of

Which of the following devices will receive voltage surge first travelling on the transmission line ?

relay is preferred for phase fault on short transmission line.

To reduce short circuit fault currents are used.

Which of the following statements is incorrect ?

Which of the following circuit breakers has high reliability and minimum maintenance ?

A.C. network analyser is used to solve problems of

Arc in a circuit breaker is interrupted at

relays are used for phase faults on long line.

A _______ is used to measure the stator % winding temperature of the generator.

Distance relays are generally

Induction cup relay is operated due to changes in

What will be the reflection co-efficient of the wave of load connected to transmission line if surge impedance of the line is equal to load ?

Which of the following statements is incorrect?

The single phasing relays are used for the protection of

Electrical Protection and Circuit Breakers

Electrical Protection and Transmission Line Characteristics

Electrical Protection and Safety: Part A

Electrical Protection and Safety: Part B

Protective Relays and Circuit Breakers for Electrical Systems

Circuit Breakers and Fuses

Electric Arc and Circuit Breaker Protection

Electrical Components and Circuit Breakers

Electrical Protection and Switchgear

Relaying Schemes and Techniques for Electrical Equipment Protection

Understanding Relays for Power System Protection

Filters