Insulation resistance of high voltage circuit breakers is more than
Insulation resistance of high voltage circuit breakers is more than
Large internal faults are protected by
Large internal faults are protected by
The arc voltage produced in A.C. circuit breaker is always
The arc voltage produced in A.C. circuit breaker is always
Directional relays are based on flow of
Directional relays are based on flow of
The relay operating speed depends upon
The relay operating speed depends upon
In a single bus-bar system there will be complete shut down when
In a single bus-bar system there will be complete shut down when
A transmission line is protected by
A transmission line is protected by
The arcing contacts in a circuit breaker are made of
The arcing contacts in a circuit breaker are made of
Fault diverters are basically
Fault diverters are basically
Protection by fuses is generally not used beyond
Protection by fuses is generally not used beyond
A balanced 3-phase system consists of
A balanced 3-phase system consists of
Interruption of large currents by relay requires
Interruption of large currents by relay requires
By which of the following methods major portion of the heat generated in a H.R.C. fuse is dissipated ?
By which of the following methods major portion of the heat generated in a H.R.C. fuse is dissipated ?
The contacts of high voltage switches used in power system are submerged in oil. The main purpose of the oil is to
The contacts of high voltage switches used in power system are submerged in oil. The main purpose of the oil is to
Distance relays are generally
Distance relays are generally
The torque produced in induction type relay (shaded pole structure) is
The torque produced in induction type relay (shaded pole structure) is
Discrimination between main and back up protection is provided by the use of relays which are
Discrimination between main and back up protection is provided by the use of relays which are
Relays are used for phase faults on long line.
Relays are used for phase faults on long line.
Ungrounded neutral transmission system is not recommended because of system
Ungrounded neutral transmission system is not recommended because of system
Transmission line has reflection coefficient as one.
Transmission line has reflection coefficient as one.
Bus coupler is very essential in arrangement
Bus coupler is very essential in arrangement
A fuse in a motor circuit provides protection against
A fuse in a motor circuit provides protection against
In Railway applications ______ circuit breaker is used.
In Railway applications ______ circuit breaker is used.
The fuse wire, in D.C. circuits, is inserted in
The fuse wire, in D.C. circuits, is inserted in
For which of the following protection from negative sequence currents is provided ?
For which of the following protection from negative sequence currents is provided ?
Which of the following is the least expensive protection for overcurrent is low voltage system ?
Which of the following is the least expensive protection for overcurrent is low voltage system ?
The material used for fuse must have
The material used for fuse must have
An isolator is installed
An isolator is installed
Thermal overload relays are used to protect the motor against over current due to
Thermal overload relays are used to protect the motor against over current due to
The ground wire should not be smaller than No ______ copper.
The ground wire should not be smaller than No ______ copper.
A switchgear is device used for
A switchgear is device used for
The line insulation is the insulation level of the station equipment.
The line insulation is the insulation level of the station equipment.
Circuit breakers are essentially
Circuit breakers are essentially
Admittance relay is _______ relay.
Admittance relay is _______ relay.
The single phasing relays are used for the protection of
The single phasing relays are used for the protection of
On which of the following effects of electric current a fuse operates?
On which of the following effects of electric current a fuse operates?
________ relay is preferred for phase fault on short transmission line.
________ relay is preferred for phase fault on short transmission line.
The short circuit in any winding of the transformer is the result of
The short circuit in any winding of the transformer is the result of
In order that current should flow without causing excessive heating or voltage drop, the relay contacts should
In order that current should flow without causing excessive heating or voltage drop, the relay contacts should
Which of the following circuit breakers has high reliability and minimum maintenance ?
Which of the following circuit breakers has high reliability and minimum maintenance ?
The interaction between a transmission line and communication line is minimized by
The interaction between a transmission line and communication line is minimized by
Overload relays are of type.
Overload relays are of type.
The voltage appearing across the contacts after opening of the circuit breaker is called______voltage.
The voltage appearing across the contacts after opening of the circuit breaker is called______voltage.
The steady state stability of the power system can be increased by
The steady state stability of the power system can be increased by
A.C. network analyzer is used to solve problems of
A.C. network analyzer is used to solve problems of
The inverse definite mean time relays are used for over current and earth fault protection of transformer against
The inverse definite mean time relays are used for over current and earth fault protection of transformer against
Series capacitors are used to
Series capacitors are used to
Shunt capacitance is neglected while considering
Shunt capacitance is neglected while considering
H.R.C. fuse, as compared to a rewirable fuse, has
H.R.C. fuse, as compared to a rewirable fuse, has
For which of the following ratings of the transformer differential protection is recommended ?
For which of the following ratings of the transformer differential protection is recommended ?
Over voltage protection is recommended for
Over voltage protection is recommended for
Protective relays are devices that detect abnormal conditions in electrical circuits by measuring
Protective relays are devices that detect abnormal conditions in electrical circuits by measuring
A _______ is used to measure the stator % winding temperature of the generator.
A _______ is used to measure the stator % winding temperature of the generator.
A fuse is connected
A fuse is connected
D.C. shunt relays are made of
D.C. shunt relays are made of
A thermal protection switch can protect against
A thermal protection switch can protect against
Relays can be designed to respond to changes in
Relays can be designed to respond to changes in
In a circuit breaker the basic problem is to
In a circuit breaker the basic problem is to
On which of the following routine tests are conducted ?
On which of the following routine tests are conducted ?
Ionization in circuit breaker is facilitated by
Ionization in circuit breaker is facilitated by
Which of the following parameter can be neglected for a short line?
Which of the following parameter can be neglected for a short line?
Which of the following devices will receive voltage surge first travelling on the transmission line ?
Which of the following devices will receive voltage surge first travelling on the transmission line ?
Arc in a circuit behaves as
Arc in a circuit behaves as
With which of the following, a circuit breaker must be equipped for remote operation ?
With which of the following, a circuit breaker must be equipped for remote operation ?
Short-circuit currents are due to
Short-circuit currents are due to
The main function of a fuse is to
The main function of a fuse is to
The delay fuses are used for the protection of ________ .
The delay fuses are used for the protection of ________ .
Oil switches are employed for
Oil switches are employed for
The information to the circuit breaker under fault conditions is provided by
The information to the circuit breaker under fault conditions is provided by
When a wave propagates on a transmission line, it suffers reflection several times at
When a wave propagates on a transmission line, it suffers reflection several times at
Circuit breakers usually operate under
Circuit breakers usually operate under
Series reactors should have
Series reactors should have
If the fault occurs near the impedance relay, the VII ratio will be
If the fault occurs near the impedance relay, the VII ratio will be
Wave trap is used to trap waves of
Wave trap is used to trap waves of
Air blast circuit breaker is used for
Air blast circuit breaker is used for
The reflection co-efficient at the open circuited end of a transmission line.
The reflection co-efficient at the open circuited end of a transmission line.
Burden of a protective relay is the power
Burden of a protective relay is the power
Overfluxing protection is recommended for
Overfluxing protection is recommended for
The under voltage relay can be used for
The under voltage relay can be used for
The time of closing the cycle, in modern circuit breakers is
The time of closing the cycle, in modern circuit breakers is
To limit short-circuit current in a power system are used
To limit short-circuit current in a power system are used
A short-circuit is identified by
A short-circuit is identified by
To protect most of the electrical equipment handling low power, the types of relays used are
To protect most of the electrical equipment handling low power, the types of relays used are
The power loss is an important factor for the design of
The power loss is an important factor for the design of
Overheating of relay contacts or contact born out is due to
Overheating of relay contacts or contact born out is due to
H.R.C. fuses provide best protection against
H.R.C. fuses provide best protection against
An efficient and a well designed protective relaying should have
An efficient and a well designed protective relaying should have
Induction cup relay is operated due to changes in
Induction cup relay is operated due to changes in
To reduce short circuit fault currents are used.
To reduce short circuit fault currents are used.
When a transmission line is energized, the wave that propagates on it is
When a transmission line is energized, the wave that propagates on it is
Resistance grounding is used for voltage between
Resistance grounding is used for voltage between
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 ?
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 ?
The fuse rating is expressed in terms of
The fuse rating is expressed in terms of
Air blast circuit breakers for 400 kV power system are designed to operate in
Air blast circuit breakers for 400 kV power system are designed to operate in
A differential relay measures the vector difference between
A differential relay measures the vector difference between
Thermal circuit breaker has
Thermal circuit breaker has
Magnetic circuit breaker has ______ trip action.
Magnetic circuit breaker has ______ trip action.
The relay with inverse time characteristic will operate within
The relay with inverse time characteristic will operate within
For the protection of power station buildings against direct strokes the requirements are
For the protection of power station buildings against direct strokes the requirements are
A fuse is never inserted in
A fuse is never inserted in
Which of the following medium is employed for extinction of arc in air circuit breaker ?
Which of the following medium is employed for extinction of arc in air circuit breaker ?
Arc in a circuit breaker is interrupted at
Arc in a circuit breaker is interrupted at
The inductive interference between power and communication line can be minimized by
The inductive interference between power and communication line can be minimized by
For cost and safety, the outdoor substations are installed for voltages above
For cost and safety, the outdoor substations are installed for voltages above
The fuse blows off by
The fuse blows off by
