Q.1
The under voltage relay can be used for
  • (a) generators,
  • (b) busbars,
  • (c) transformers,
  • all of the above
Q.2
Resistance grounding is used for voltage between
  • 33kVto66kV
  • 3.3kVand ll kV
  • 2.2 KV to 3.3 KV
  • above 11KV
Q.3
Large internal faults are protected by
  • merz price percentage differential protection,
  • mho and ohm relays
  • horn gaps and temperature relays.
  • earth fault and positive sequence relays
Q.4
Shunt capacitance is neglected while considering
  • short transmission line
  • medium transmission line
  • long transmission line
  • medium and long transmission lines
Q.5
The line insulation is the______ insulation level of the station equipment.
  • less than
  • same as,
  • more than,
  • not directly related with
Q.6
Underground neutral transmission system is not recommended because of system
  • insulation being overstressed due to over voltages
  • insulation overstress may lead to failure and subsequent phase to phase faults,
  • being inadequately protected against ground fault
  • all of the above.
Q.7
When a wave propagates on a transmission line, it suffers reflection several times at
  • tapping,
  • load end,
  • sending end,
  • sending and other end
Q.8
For which of the following ratings of the transformer differential protection is recommended ?
  • above 30 kVA.
  • equal to and above 5 MVA,
  • equal to and above 25 MVA,
  • none of the above
Q.9
In a single bus-bar system there will be complete shut down when
  • fault occurs on the bus itself,
  • fault occurs on neutral line
  • two or more faults occur simultaneously,
  • fault occurs with respect to earthing
Q.10
Which of the following statements is incorrect?
  • Station batteries are used to operate relay only
  • The lightning arresters are basically surge diverters
  • An impedance relay has maximum fault current when fault occurs near the relay
  • A high speed relay has an operation of 1 to 2 cycles.
Q.11
Wave trap is used to trap waves of
  • Power frequencies,
  • Higher frequencies entering generator or transformer units
  • Either of the above,
  • None of the above.
Q.12
For which of the following protection from negative sequence currents is provided ?
  • Generators,
  • Motors
  • Transmission line
  • Transformers
Q.13
A voltage source can be converted into constant current source by adding
  • Low resistance in parallel with the voltage source
  • High resistance in parallel with the voltage source
  • Low resistance in series with the voltage source
  • High resistance in series with the voltage source
Q.14
The short circuit in any winding of the transformer is the result of
  • mechanical vibration,
  • insulation failure,
  • loose connection,
  • impulse voltage
Q.15
Bus coupler is very essential in arrangement
  • single bus,
  • double bus, double breaker,
  • main and transfer bus,
  • all of the above.
Q.16
The interaction between a transmission line and communication line is minimized by
  • (a) transposing transmission as well as communication lines.
  • (b) increasing the height of the trans-mission line tower
  • (c) increasing the distance between the two lines
  • (d) all of the above
Q.17
Over fluxing protection is recommended for
  • (a) distribution transformer,
  • (b) generator transformer of the power plant
  • (c) auto-transformer of the power plant,
  • (d) station transformer of the power plant
Q.18
The objective of a protection scheme is to keep the power system is
  • stable
  • safe
  • reliable
  • all of the above
Q.19
What are the isolation requirements for an electric hot plate?
  • 4.7.1
  • 4.7.1 Note
  • 4.8.1
  • 8.3
Q.20
Is an isolator required for an enclosed cooking appliance such as a wall oven?
  • 4.7
  • 2.10
  • 4.7.1
  • 4.19
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