POWER PLANT

1. What do you call the protective angle between the Overhead ground wire and the power cable in the Transmission tower a. surge angle b. clearing angle c shielding angle d. arcing angle

2. Disconnecting switch is provided for proper protection of electric substations and power plant.

What is its main function. a. for protection of circuit breaker b. to break the system under fault c. for complete isolation d. for maintenance purpose

3. The highest magnitude of fault current will determine the size of _________, while the lowest

magnitude will determine the size of_____________. a. circuit breaker, relay b. circuit breaker, isolator c. fuse, relay d. relay, circuit breaker

4. The PTs of a 220 kV transmission line have ratio of 132.76 kV: 66.375 V and are connected

wye-wye. A voltmeter connected line to ground reads 66 V, what is the transmission line voltage?

a. 228.63 kV b. 223.15 kV c. 220.10 kV d. 225.25 kV 5. The transfer bus scheme has the following characteristics EXCEPT one. Which one of this?

a. It allows the disconnection of circuit breakers for maintenance without Interrupting the service

b. It is more flexible c. It allows better continuity of service as compared with the single bus d. It is more costly than that of the single bus system

6. Double-bus double breaker scheme has the following characteristics EXCEPT one, which

one is this? a. Even with a circuit breaker failure, a station shutdown will not result. b. It reduces the likelihood of extended outages of any circuit due to circuit breaker

trouble. c. It permits breaker maintenance without feeder outage. d. It gives more flexibility.

7. A large electric power distribution system is protected against surges and faults by

a. protective gaps crossing drain cells b. high-speed relays detecting the trouble c. protective relays operating without a time delay d. radio communication system using flow frequency

8. Which of the following steps is used for isolating a circuit breaker for maintenance purposes?

a. pull the substation fuses b. turn off the main generator c. open the disconnect switches d. ground the auxiliary contacts

9. In a generating and distribution system, current balance is provided by protective zones

which are a. used to eliminate reflections on short transmission lines b. used to trip all circuit breakers in the system c. isolated during fault by disconnect switches d. monitored by differential relays

10. For protection of parallel feeders fed from one end the relays required are:

a. Non-directional relays at the source end and directional relays at the load end b. Non-directional relays at both the ends. c. Directional relays at the source end and non-directional at the load end. d. Directional relay at both the ends.

11. If a fixed amount of power is to be transmitted over a certain length with fixed power loss, it

can be said a. the volume of conductor required is inversely proportional to the square of

voltage and that of the power factor of load b. the volume of the conductor is inversely proportional to voltage and that of power

factor of load c. the volume of the conductor is proportional to square of the voltage and directly

proportional to power factor of load d. the volume of the conductor required is proportional to voltage only

12. Assuming the constant efficiency transmission, if the voltage is increased n times, the size of

the conductor would be a. reduced to 1/n2 that of the original b. increased to n2 that of the original c. reduced to 1/n that of the original d. increased to n times that of the original

13. In a distribution system, if the synchronous capacitors are to be used for improving the power

factor, the correct location would be a. at the sending end b. at the receiving end c. in middle of the transmission line d. none of the above

14. In limiting case, the maximum cost of the phase advancing plant that would justify its

installation is when its working cost is a. equal to the working cost of generating plant to give the same increase in

power b. equal to working cost of the generating plant to give the less increase in power c. less than the working cost of generating plant to give the same increase in power d. greater than the working cost of the generating plant to give more increase in power

15. The synchronizing power developed in the parallel operation of the alternators will be

maximum when a. the armature have more reactances than their resistances b. the armature have less reactances than their resistances c. the armature reactances equal to their resistances d. the resistances of armatures are zero

16. The actual division of the total kW load between alternators in power plant running in parallel

depends upon the a. speed-load characteristic b. voltage-load characteristic c. a and b both d. a or b

17. Natural Uranium contains

a. 0.7% U235 b. 0.7% U235 c. 100% U235 d. 50% U235

18. Which of the following will affect the transfer of the real power between the stations if they are interconnected? a. Quadraturel voltage b. In-phase voltage boost c. Reactance d. angular displacement between stations

19. The size of the feeder is determined primarily by

a. the current it is required to carry b. the percentage variation of voltage in the feeder c. the voltage across the feeder d. the distance over which the transmission is made

20. If the voltage is increased n times, the current in the feeder is reduced to (for a given power

delivered) a. 1/n times of the original b. 1/n2 times of the original c. 1/ n times of the original d. n times of the original

21. In the d.c. three wire transmission system the cross-section of the neutral is generally

a. of the outer conductors b. of the outer conductors c. of the outer conductors d. equal to the outer conductors

22. The Metal clad is related to

a. Amplidyne b. Switchgear system c. Synchros d. Relays

23. The power transmission capacity of the transmission line is

a. proportional to the square of the operating voltage b. inversely proportional to the voltage c. proportional to the voltage d. inversely proportional to the square of the voltage

24. Which of the following power plant has the maximum efficiency?

a. Thermal power plant b. Hydro-electric power plant c. Atomic Reactor d. MHD

25. The reactors used in most power station specially in HVDC is to limit the short circuit current

in the alternators have very small resistance in comparison to reactance a. because the high resistance will not help to limit the short circuit current b. to avoid the energy waste c. because the high resistance will raise the temperature and insulation of reactor will

be spoiled d. to improve power factor

26. The earthing transformer is used

a. to avoid the harmonics in the transformers b. to provide artificial neutral earthing where the neutral points of the three phase

system are not accessible c. to improve the current capacity of the neutral wire d. none of the above

27. To protect the power transformer (Y-Y, with neutral earthed) in power station against fault,

the current transformer will have a. Delta-delta connection b. Delta-star connection c. Star-delta connection d. Star-star connection

28. To protect the power transformer (Delta-delta) against fault, the current transformer will have

a. Delta-delta connection b. Delta-star connection c. Star-delta connection d. Star-star connection

29. Which of the following power system distribution gives the greater reliability?

a. radial system of the distribution b. ring system of the distribution c. D.C. three wire system of the distribution d. A.C. three phase four wire system

30. The diversity factor is defined as the

a. Average demand Maximum demand

b. Sum of consumers maximum demand

Maximum load on the station

c. Maximum demand Sum of consumers maximum demand

d. Average demand Maximum load on the station 31. The power intended to be available even under emergency condition is called

a. firm power b. hot reserve c. cold reserve d. spinning reserve

32. Which of the following generating stations has the minimum running cost?

a. Hydro-electric station b. Nuclear power station c. Thermal power station d. Diesel power plant

33. Overfluxing protection is recommended for

a. generator transformer of the power plant b. auto-transformer of the power plant c. station transformer of the power plant d. Distribution transformer

34. Which of the following statements is true if restricted earth fault protection is provided to star

winding of the generator transformer a. one Ct in each phase and fourth in the neutral are provided and their

secondaries are connected in parallel b. one CT is provided in the neutral c. two CTs are provided, one in R-phase and other Y phase with a CT in neutral d. in fact CTs are not required at all as the fault current is not very high

35. Series capacitors are used to

a. improve line voltage b. compensate line inductive reactance c. compensate line capacitive reactance d. improve impedance

36. High water level of a boiler drum can damage

a. boiler tubes b. turbine and steam line c. turbine only d. none of the above

37. Which of the following statements is true? a. Shunt reactors are used for power factors improvement. b. Shunt reactors are used to control the line voltage. c. Shunt reactors are used to reduce the line impedance. d. Shunt reactors are used to eliminate line to ground capacitance.

38. When a stator neutral of a generator is earthed through a distribution transformer, the stator

earth fault is detected through a. an over-voltage relay connected across the secondary of the transformer b. an over-current relay connected across the secondary of the transformer c. an under-voltage relay connected across the secondary of the transformer d. none of the above

39. If high pressure heaters of steam cycle in power plant have high water level, what precaution

shall be taken. a. trip the turbine b. trip the boiler c. trip the boiler feed pump d. bypass the heater from water side and close extraction value

40. Which one of the following statements is not true?

a. Fault levels in an all a. c system are less than in an a. c system with a D.C. link operating

b. Large systems may be interconnected with d. c link of small capacity c. Limitation on the critical length of underground cables for use in A. C no longer exists

if D.C transmission by cables is used. d. Corona loss and radio and TV interference with D.C. transmission is less

41. Advantage of power system interconnection is

a. Large size circuit breakers are required because of large short-circuit currents b. Machines of one system remain in step with machines of another system c. Fewer machines are required as reserve for operation at peak loads d. Optimization of machine can be done properly

42. Economic studies have shown that D.C. transmission is cheaper than a. c transmission for

lengths a. below 300 km b. beyond 600 km c. beyond 1200 km d. less than 100 mile

43. Governors for controlling the speed of power generation units provide

a. A flat speed -load characteristics b. An increase of speed with increasing load c. Speed is proportion with the load d. A decrease of speed with increasing load

44. When two identical generating units are operated in parallel on governor control, and one

machine has a 5% governor droop and the other a 10 % droop , the machine with the greater governor droop will

a. Tend to take the greater portion of load changes b. Share load equally with the other machine c. Tend to take the larger portion of load changes. d. Tend to take the lesser portion of load changes.

45. On load-frequency control installations, error signals are developed proportional to the

frequency error. If frequency declines , the error signal will act to a. Increase prime move input to the generators b. Reduce prime mover input to the generators c. Increase generator voltages d. Increase impedance of the line

46. When inter-connected power systems operate with tie-line bias, they will respond to

a. Frequency changes only b. Both frequency & tie -line load changes c. Tie-line load changes only d. Drooping voltage

47. When generating units in a power plant are loaded with equal incremental costs, the cost of

generation is a. maximum b. minimum c. not affected d. zero

48. Incremental heat - rate curves for thermal generating units are used to determine the

a. fuel cost in P/hour b. values to which the units should be loaded to decrease the fuel costs to a

minimum c. none of the above. d. Optimal cost

49. In economic operation of a power system , the effect of increased penalty factor between a

generating plant and system load centre is a. to decrease the load on the generating plant b. to increase the load on the plant c. to hold the plant load constant. d. To maintain power factor of the plant

50. Non-conventional source-based power plants are generally best suited for

a. Working with the nearby power grid b. Isolated operation from the power grid c. Operation with similar plants irrespective of length of connecting transmission system d. Island

51. Running cost of a hydro plant with respect to that of a thermal plant is

a. More b. Less c. Varying from installation to installation d. equall

52. Pick up the odd plant from the following

a. Steam b. Hydro c. Tidal d. Nuclear 53. Pick up the odd plant from the following:

a. Steam b. Wind turbine generator plant c. Tidal d. Solar

54. The role of the economiser is to pre-heat

a. Pulverised coal b. Boiler feed water c. Air used for combustion d. provide clean air

55. Superheater & reheater are used to

a. improve the condition of steam b. heat air used for combustion c. heat boiler feed water d. decrease efluent

56. Governor is used with the steam turbine to regulate

a. Steam temperature b. Steam pressure c. Power output d. Speed

57. Cooling of 500 MW turbo-generators is usually done by the following coolants

a. Nitrogen & hydrogen b. Hydrogen & water c. Carbon dioxide & hydrogen d. Water only

58. The specific speed of a hydro turbine depends on

a. Actual speed b. Head of operation c. Output power d. Actual speed ,head of operation & output power

59. The most common type of hydro turbine with a moderate value of the specific speed is

a. Pelton b. Francis c. Kaplan d. wind 60. Pumped storage hydroelectric plant can be operated with

a. Upstream reservoir only b. downstream reservoir only c. with both as above d. none of the above

61. Hydro-generators are usually

a. Round rotor machines b. Salient pole machines c. Homopolar machines d. Bipolar machine

62. Heavy water in a nuclear reactor is used for

a. Cooling & moderation b. Cooling and shielding radiation c. Moderation & shielding radiation d. Moderation only

63. The size and weight per unit power of a fast breeder reactor in comparison to a reactor of any

of the thermal types is a. Much less b. Much more c. more or less the same d. always zero

64. Compared to turbines in the conventional coal-fired thermal stations, nuclear power plant

turbines use steam at a. higher pressure & temperature b. lower pressure & temperature c. higher temperature & lower pressure

d. higher power factor 65. Gas turbine temperature corresponds to

a. Boiling water temperature of 100 deg.C b. Superheated steam temperature of 550 deg.C c. Around 1000 deg.C d. Around 66000 deg C

66. Gas turbine works on

a. Rankine cycle b. Brayton cycle c. Carnot cycle d. Roel cycle

67. The HVDC converter

a. Does not consume reactive power b. Consumes as much reactive power as real power c. Consumes 50% of the real power d. Is not economical

68. A back to back HVDC link can be advantageous compared to AC primarily because

a. It is cheaper b. Of stability considerations c. Of controlled power glow d. It is costly

69. A 12-pulse bridge is preferred in HVDC because

a. It eliminates certain harmonics b. It results in better power factor c. Series connection of converters on D.C. side is better d. cheaper

70. Fault on a two terminal DC link is removed by

a. Breakers on DC side b. Breakers on AC side c. Current control of converters d. Current chopping

71. From the economic point of view , a power system should have a load factor

a. About 0.12 b. About 0.5 c. About1 d. zero

72. From the economic point of view , a power system should have a diversity factor

a. Much less than 1 b. Nearly equal to but less than one c. Always constant d. Greater than one

73. Peak load hydro power plants compared to base load thermal plants have plant capacity

factor a. Much lower b. Much higher c. Almost equal d. Always constant

74. Run-of-river plants are used for

a. Base load operation b. Peak load operation c. Near base load d. Regulating plant

75. The two-part tariff is based on

a. MW and MVar b. MW and MVA c. MWH and MVA d. MVArH

76. SF6 gas has excellent heat transfer properties because of its:

a. Higher molecular weight. b. High gaseous viscosity. c. Low density d. Low cost

77. In order to have lower cost of electrical energy generation:

a. The load factor and diversity factor should be low. b. The load factor should be low but diversity factor should be high. c. The load factor should be high but diversity factor low. d. The load factor and diversity factor should be high.

78. For stability and economic reasons we operate the transmission line

with power angle in the range: a. 10 deg. to 25 deg. b. 30 deg. to 45 deg. c. 60 deg to 75 deg. d. 65 deg. to 80 deg.

79. For an existing a. c. transmission line the string efficiency is 80%. Now if d.c. voltage is

supplied for the same set up, the string efficiency will be: a. 80%. b. More than 80%. c. Less than 80%. d. 100%.

80. Effect of increase in temperature in overhead transmission lines is to:

a. Increase the strength and length. b. Decrease the strength and length. c. Decrease the stress but increase the length. d. None of the above.

81. For economic operation, the generator with highest positive incremental transmission loss will

operate at: a. The lowest positive incremental cost of production. b. The lowest negative incremental cost of production. c. The highest positive incremental cost of production. d. None of the above.

82. An alternator is delivering the load current; its percent regulation is found to be zero. The

type of load it delivers is: a. Capacitive. b. Inductive. c. Resistive. d. admittance

83. The incremental transmission loss of a plant is:

a. Positive always. b. Negative always. c. Can be positive or negative. d. zero

84. Load flow study is carried out for:

a. Fault calculations. b. Stability studies. c. System planning. d. Load frequency control.

85. If the penalty factor of a plant is unity, its incremental transmission loss is:

a. 1.0. b. 1.0. c. Zero. d. 10.0

86. If the load of an isolated generator is increased without increasing the power input to the

prime mover: a. The generator will slow down. b. The generator will speed up. c. The generator voltage will increase. d. The generator field current will increase.

87. When alternative sources of energy are available to a power system, they should be

Used in such a way that: a. Thermal generation is held at a minimum. b. The most efficient plants are always loaded to their maximum. c. Overall production cost is minimized. d. Near at the load point

88. In a thermal-electric generating plant, overall efficiency is improved when:

a. Boiler pressure is increase. b. The difference between initial pressure and temperature and exhaust pressure

and temperature are held at a maximum. c. Load on the units is increased. d. It is always loaded

89. When load on a thermal unit is increased, fuel input

a. Increase. b. Does not change. c. Decrease. d. It is constant

90. Incremental-heat-rate curves, for thermal generating units, are used to determine the

a. Fuel cost in P per hour. b. Values to which the units should be loaded to result in minimum fuel cost. c. Cost per unit of electrical output. d. Ramp rate

91. When generating units are loaded to equal incremental cost:

a. Minimum fuel cost result. b. Fuel cost is at a maximum. c. Fuel cost is not affected. d. Losses are minimized

92. One advantage of computer control of generating units is that:

a. Var output of the unit is minimized. b. All units under the control of the computer will be loaded to the same load. c. Loading of the units will be frequently adjusted to maintain them at equal d. Incremental fuel costs.

93. If the fuel cost of one unit, operating in parallel with other units, is increased and it

is desired to maintain fuel cost, the load on the unit will be a. Increase. b. Held constant. c. Decrease.

94. In a power system using both hydro and thermal generation, the proportion of hydro

generation can be increased by a. Increasing the prize (gamma) of the water. b. Reducing the prize of the water. c. Increasing the field currents of the hydro generators. d. Used water with high specific gravity

95. In economic operation of a power system, the effect of increased penalty factor

between a generating plant and system load center is to a. Decrease load on the generating plant. b. Increase load on the plant. c. Hold the plant load constant.

96. Governors for controlling the speed of electric generating units normally provide

a. A flat speed load characteristic. b. An increase of speed with increasing load. c. A decrease of speed with increasing load.

97. On load frequency-control installation, error signals are developed proportional to the

frequency error. If frequency decline, the error signal will act to a. Increase prime mover input to the generators. b. Reduce prime mover input to the generators. c. Increase generator voltages.

98. When to or more system operate on an interconnected basis, each system

a. Can depend on the other systems for its reserve requirements. b. Should provide for its own reserve capacity requirement. c. Should operate in a flat frequency mode.

99. When interconnected power system operate with tie-line bias, they will respond to

a. Frequency changes only. b. Both frequency and tie-line load changes. c. Tie-line load changes only.

100. A metering installation for a 115-kV tie point between two power system has 10000:5

current transformers in each phase and 600:1 potential transformers connected line to ground. Assuming unity power factor, the multiplying factor that should be used to determine the power in the circuit in kilowatts is a. 360 b. 3600 c. 207.8

101. Inadvertent energy accumulation between power system are normally balanced by

scheduling compensating deliveries of power a. During off-pick periods. b. During periods corresponding to those in which the inadvertent energy was

accumulated. c. On week ends.

102. Wired supervisory control system are

a. Less expensive when many devices are to be controlled. b. More reliable than computer-based systems. c. Limited by cost and complexity when many devices are to be controlled. d. Immune from induced electrical interference.

103. SCADA systems require

a. A separate communication channel for each RTU b. Continuous attendance at each remote station. c. Frequency-shift data channels to the RTU. d. A mean of entering and retrieving data at the master unit.

104. One of the factor affecting power system reliability is

a. The nominal system transmission-voltage levels. b. The ratio of hydro to thermal generation. c. The available reserve capacity margin.

105. Spinning reserve is generating capacity that

a. Is available by starting gas-turbine generating units. b. Is synchronous and online, with capacity in excess of existing loads. c. Has the lowest fuel cost.

106. The spinning reserve to be carried on a system is

a. Determined by the system operator (dispatcher). b. A policy matter. c. Determined by the amount of load on the system.

107. The risk affecting spinning-reserve requirement of a system, in addition to the most

heavily loaded units, include a. The net amount of imported power. b. The net amount of exported power. c. The time of the daily peak load.

108. Spinning reverse should

a. Be divided among units at various locations on a system. b. Be carried on the largest unit available. c. Be reduced during off-peak hours.

109. In the event of a major loss of generation in an interconnected area, a system operator

should a. Immediately open tie lines to other system. b. Open tie lines if power is flowing out of the system. c. Open tie lines only as a last resort with power flowing out and declining

frequency. 110. House units are sometimes provided at thermal power plants to

a. Provide for station and yard light. b. Keep the station batteries charged. c. Supply power to plant auxiliaries.

111. Of the Lightning arresters sold in the market, which can handle much large surge current

and excessive contamination of dirt. a. Distribution arrester b. intermediate arrester c. station arrester d. line arrester

112. The Location of lightning arrester should be

a. near the transformer b. away from the transformer c. near the circuit breaker d. near from the disconnect

113. The choice between ac and dc transmission is determined by:

a. Engineering and economic factors. b. The size of the conductors. c. The operating voltage.

114. The ratio of the average load on the plant for the period of time considered to the

aggregate rating of all the generating equipments a. Capacity factor b. Utilization factor c. Load factor d. Diversity factor

115. The most economical size of a feeder is that size for which the annual cost of energy lost

in the feeder equals the cost of interest and depreciation on the capital cost of the conductor material. a. Kirchoffs Law b. Law on Economics c. Faradays Law d. Kelvins Law

116. Minimum oil circuit breaker is preferred in

a. low voltage b. Medium voltage c. High voltage d. Extra High voltage 117. Breaking Capacity of circuit breakers is expressed in.

a. MVA b. KAIC c. kV d. AH 118. Type of water wheels used in hydraulic plants

a. propeller c. impulse b. reaction d. all of these

119. Power plant curves or graphs showing the direct relationship of the peak load and the

generated energy of the said plant a. modified load curve c. load duration curve b. load curve/graph d. none of the above

120. The advantage of using static capacitor to improve the power factor is because they

a. are most loss free b. provide continuous charge of power factor c. none of these d. are not variable

121. Is an equipment which controls the gate or valve opening of the prime mover:

a. silicon controlled rectifier b. contactor c. rheostat d. governor

122. Is the mechanism which is used for moving a removable circuit breaker unit to end from

the connected, disconnected and test positions: a. permissive control device b. notching device c. blocking device d. position changing system

123. Is used to increase or decrease in one step, the value of feild excitation on a machine:

a. tripping relay b. filed regulator c. DC reclosing relay d. field changing contactor

124. In a generating and distribution system, current balance is provided by protective zones

which are: a. used to eliminate reflections on short transmission lines b. used to trip all circuit breaker in the system c. isolated during fault by disconnect switches d. monitored by differential relays

125. In switchgear application, the term dead fronts means that

a. the front and rear panels are hinged b. an access door is at the end of the structure c. no equipment is mounted on the front panel d. energized parts are not exposed on the front panel

126. Which of the following steps is used for isolating a circuit breaker in power stations for

maintenance purposes? a. pull the substation fuses b. turn off the main generator c. open the disconnect switches d. ground the auxiliary contacts

127. The ratio of the average load on the plant for the period of time to the aggregate rating of

all generating equipment a. Plant use factor

b. capacity factor c. power factor d. maintenance factor

128. The ratio of the individual maximum demands of the systems to the overall maximum

demand of the whole system a. load factor b. diversity factor c. utilization factor d. demand factor

129. In parallel operation of alternator, if the excitation of one alternate is changed it will only

change a. real power taken by the machine b. reactive power taken by the machine c. apparent power taken by the machine d. synchronizing power of the machine

130. The maximum past or present demand, which are taken into account to establishing

billings for the previous or subsequent periods. a. Ratchet Demand b. diversity demand c. Seasonal Diversity d. meter demand

131. The ratio of the maximum coincident total demand of a group of consumers to the sum of

the maximum power demand of the individual consumers comprising the group both taken at the same point of supply for the same time.

a. Non- Coincidence factor b. Coincidence factor c. Plant use (Output) factor d. Utilization Factor

132. The ratio of the average load for a given period to the operating capacity in actual service

only (for multi-set plant). a. Capacity factor b. Load factor c. Diversity factor d. Demand factor

133. The product of the load factor (LF) and the demand factor (DF).

a. Plant factor b. Use Factor c. Average factor d. Connected Load factor

134. The water enters the spiral case from the penstock, passes through the stay ring guided

by the stationary stay ring vanes, then through the movable wicket gates through the runner and into the draft tube through which it flows into a tailrace or tailwater reservoir. This type of hydraulic turbine is known as a. Francis type b. Propeller type c. Axial flow turbine d. Impulse Turbine

135. It pertains to the units available, maintained at operating temperature and ready for

service although not in actual operation. a. cold reserve b. Hot reserve c. spinning reserve d. Operating reserve

136. It is the product of the Utilization factor (UF) and Load factor (LF).

a. Capacity factor b. Use Factor c. Average factor d. Connected Load factor

137. To produce one kW-hr a power plant burns 0.9 lb of coal with a heating value of 13,000

BTU per lb. What is the heat rate of the plant?

a. 6,250 BTU/kW-hr b. 11,700 BTU/kW-hr c. 9,500 BTU/kW-hr d. 8,700 BTU/kW-hr

138. A 100 MW power plant has a heat rate of 2.88 x 10 6 calories per kW-hr. It is a base load

plant and runs at full load 24 hrs a day. How many tons of coal is needed per day? a. 250 b. 625 c. 830 d. 960

139. The feedwater is usually heated before it is injected to the boiler for the following reason

EXCEPT one. Which one is this? a. Improves the overall performance of the plant b. Recover part of the flue gas heat which is otherwise lost to the atmosphere c. Derating types of preheaters permit the removal of dissolves gases from the

feedwater d. Increase the efficiency of the boiler

140. An effective remover of dust, carbon particles and others from the flue gas of the power

plant is called _____. a. Electrostatic Precipitator b. Soot blower and collector c. Mechanical collector d. Dust scrubber

141. It is the modern equipment of removing sulfur content from the flue gas of the power

plant. a. ESP b. EMS c. FGD d. DAC

142. In fission, energy is produced when.

a. Chemical compound splits into its constituents b. Nuclear particles combine c. Nuclear particles split d. Molecules combine

143. In the list below which one is not a type of present day nuclear power plant.

a. boiling water c. low pressure reactor b. fusion-fission reactor d. fast breeder reactor

144. How does the output of the hydraulic turbine vary with the diameter of the blade?

a. It varies directly as the square of the diameter of the blade b. It varies directly as the two-thirds power of the diameter of the blade c. It varies directly as the diameter of the blade d. It varies directly as the cube of the diameter of the blade

145. A ten-year investigation of rivers potential gave an average water flow of 25 cm per

second at the bottom and 90 cm per second at the surface. The average cross section at the same location is 80 sq. m. What is the average flow rate in cubic meter per hour? a. 165,000 b. 57,500 c. 46,500 d. 5,760

146. A power plant gets water from a dam from a height of 122.45 meters at the rate of 1,000

cubic meters per minute. If the output of the plant is 15,000 kW, what is the efficiency? a. 80% b. 70% c. 75% d. 65%

147. An industry having a maximum demand of 1000 kW works for 320 days in a year, 8 hrs

per day. Assuming that it works at full capacity all the time during working days, calculate the daily load factor. a. 56.2 % b. 67 % c. 33.3 % d. 29.5 %

148. A 100 MW power station delivers 100 MW for 2 hrs, 50 MW for 6 hrs and is shut down for

the rest of each day. It is also shut down for maintenance for 45 days each year. Calculate the annual load factor. a. 20.1 % b. 56.9 % c. 20.83% d. 78.5%

149. A power station has a load cycle as follows:

260 MW for 6 hrs 200 MW for 8 hrs 160 MW for 4 hrs 100 MW for 6 hrs If the power station is equipped with 4 sets of 75 MW each, calculate the capacity factor. a. 61.1 % b. 34.5 % c. 23.6 % d. 76.5 %

150. The current loads of four circuits are as follows:

Circuit no 1 = 25 Amperes Circuit no 3 = 18 Amperes Circuit no 2 = 38 Amperes Circuit no 4 = 45 Amperes If the diversity factor is 1.5. What is the minimum ampacity of the feeder conductor?

a. 126 Amperes b. 189 Amperes c. 84 Amperes d. 152 Amperes 151. The metering of a power customer was read and gave the following data:

KW-hr = 200,000 KVAR- hr.= 180,000 Maximum demand = 380 kW Billing days = 3 What is the load factor?

a. 68% b. 80% c. 73% d. 62% 152. The power customer has four circuits of 220-volt three phase. The circuits have the

maximum demand as follows: Circuit no 1 = 35 Amperes Circuit no 3 = 72 Amperes Circuit no 2 = 46 Amperes Circuit no 4 = 57 Amperes The diversity factor is 1.5, the load factor is 50% and the power factor is 80%. What is the approximate kW demand of the customer? a. 15 kW b. 21 kW c. 43 kW d. 53 kW

153. . The power customer has four circuits of 220-volt three phase. The circuits have the

maximum demand as follows: Circuit no 1 = 35 Amperes Circuit no 3 = 72 Amperes Circuit no 2 = 46 Amperes Circuit no 4 = 57 Amperes The diversity factor is 1.5, the load factor is 50% and the power factor is 80%. Determine the maximum KVA demand of the customer?

a. 46 b. 80 c. 26.5 d. 53 154. A Diesel station supplies the following loads to various consumers:

Industrial consumer = 1500 kw Commercial estabkishment = 750 kw Domestic power = 100 kw Domestic light = 450 kw If the maximum demand on the station is 2500 kw and the number of kwh generated per year is 45 x 10 5, determine the diversity factor and load factor.

a. 1.12, 20.5% b. .97, 31.2% c. 1.53, 65.7% d. 21.1, 50.2% 155. A 100 MW coal fired power plant has an average heat rate of 9,500 BTU/ kWh. The plant

load factor is 75%; the heating value of coal is 12,000 BTU/ lb. Calculate the amount of coal usage for one day. a. 1.425 x 10 6 lbs. b. 2.235 x 10 5 lbs. c. 1.425 x 10 6 lbs. d. 1.826 x 10 6

lbs.

156. A Power Plant has a maximum demand of 15 MW. The annual load factor and capacity factor are 50 % and 40%, respectively. Determine the reserve capacity of the plant. a. 7350 kW b. 5370 kW c. 3750 kW d. 3075 kW

157. A diversity factor of 2.5 gives a saving of ___________ % in the generating equipment.

a. 60 b. 50 c. 40 d. 25 158. A coal Thermal Power Plant has a boiler, turbine and alternator efficiencies of 35%, 86%,

and 93% respectively. Coal with heating value of 12,000 BTU per lb cost P 1.5 per lb. What is the fuel cost in producing 1 kW? a. P 1.9 per kW b. P 1.52 per kW c. P 1.75 per kW

d. P 1.62 per kW 159. A certain coal fired power plant has a heat rate of 2.88 x 10 8 calories per kW-hr. Coal

costs P 2,500 per Ton. How much is the fuel cost component of producing 1 kW-hr? a. P 2.50 b. P 1.00 c. P 1.75 d. P 1.25 160. A power station has a load cycle as under

260 MW for 6 hrs 200 MW for 8 hrs 160 MW for 4 hrs 100 MW for 6 hrs If the power station is equipped with 4 sets of 75 MW each, calculate the daily fuel requirement if the calorific value of the oil used were 10,000 Kcal/kg and the average heat rate of the station were 2,860 Kcal/kW.

a. 1890 tons b. 3452 tons c. 7641 tons d. 1258.4 tons 161. A diesel generator set burns diesel with a heating value of 18,000 BTU per lb. The diesel

engine has an efficiency of 30% and the alternator has an efficiency of 95%. Determine the fuel cost component of producing one kW-hr if diesel cost P 2.8 per lb. a. P 0.15 b. P 2.15 c. P 3.28 d. P 1.86

162. A hydroelectric station has a turbine efficiency of 86% and a generator efficiency of 92%.

The effective head of water is 150 m. Calculate the volume of water used when delivering a load of 40 Mw for 6 hours. a. 74.18 x 10 4 m3 b. 4.158 x 10 4 m3 c. 82.54 x 10 3 m3 d. 94.48 x 10 4 m3

163. A proposed hydroelectric station has an available head of 30 m, a catchment area of 50 x

10 6 sq. m, the rainfall for which is 120 cm per annum. If 70% of the total rainfall can be collected, calculate the power that could be generated. Assume the following efficiencies: Penstock 95%, Turbine 80%, and Generator 85%. a. 253 kW b. 678 kW c. 214 kW d. 925 kW

164. The load of an instrument transformer consisting of delicate moving elements of an

ammeter, voltmeter and wattmeter is termed as (EE June 1990) a. Transformer power b. Instrument Impedance c. burden d. meter load

165. At a 155 kV substation the PT ratio is 1000:1 and the CT ratio is 1200:5. The potential

going into the wattmeter is 155 V. What is the MW indicated when the wattmeter reads 800 watts. (EE Oct 1997) a. 192 MW b. 19.2 MW c. 15.0 MW d. 150 MW

166. A diesel electric generating station supplies an output of 25 kW. The calorific value of the

fuel oil used is 12,500 Kcal/Kg. If the overall efficiency of the unit is 35%, calculate the mass of oil required per hour.

a. 4.91 kg b. 54 kg c. 7.89 kg d. 1.34 kg 167. When alternative sources of energy are available to power system, they should be used

in such a way that a. Thermal generation is held at minimum b. The most efficient plants are always loaded to their maximum c. Overall production cost is minimized d. Used Diesel Power plant

168. In thermal electric generating plant, overall efficiency is improved when

a. Boiler pressure is increased b. The difference between initial pressure and temperature and exhaust pressure

and temperature are held at a maximum c. Load on the units is increased d. Increased the no. of generator

169. One advantage of computer control of generating units is that

a. Var. output of the units are minimized b. All units under the control of the computer will be loaded to the same load c. Loading of the units will be frequently adjusted to maintain them at equal

incremental cost d. It can control all equipment

170. The most economical cross section of a conductor is that which makes the interest on the

capital outlay plus depreciation due to the conductor in the cable equal to the annual cost of energy loss. a. Ferranti law b. Kelvins law c. Mc Kevins Law d. Vanderwhaals Law

171. Inadverent accumulations between power systems are normally balanced by scheduling

compensating deliveries of power a. During off-peak load b. During periods corresponding to those in which the inadverent energy was

accumulated c. On weekends d. On base load plant

172. Spinning reserve is generating capacity that

a. Is available by starting Gas- Turbine generating units b. Is synchronized and online, with capacity in excess of existing load c. Has the lowest fuel cost d. A policy matter

173. Ferroresonance is a condition that may occur on

a. Distribution line b. Capacitor c. Transformer d. Transmission line

174. Subsynchronous resonance is a condition that may occu on

a. Short transmission line b. Long, heavily loaded line c. Loss of load on transmission line d. Increase of load on line

175. Heating value of coal largely depend on

a. ash content b. moisture content c. volatile matter d. size of coal particle

176. Power plant using coal work closely on which of the following cycle

a. Rankine cycle b. Binary vapour cycle c. Otto cycle d. Brayton cycle

177. Which of the following contributes to the efficiency of Rankine cycle in thermal power

plant. a. Used of high pressure b. Reheating of steam at intermediate stag c. Regeneration use of steam for heating boiler d. All of these

178. In steam turbine cycle, the lowest pressure occurs in

a. Turbine inlet b. Boiler c. Condenser d. Superheater 179. For low head and high discharge the hydraulic turbine used is.

a. Kaplan b. Francis type c. Pelton wheel d. Jonvas 180. Overall efficiency of Gas Turbine is

a. equal to Carnot cycle efficiency b. equal to Rankine cycle efficiency c. Less than Diesel cycle efficiency d. More than Otto or Diesel cycle efficiency

181. The function of moderator in Nuclear Reaction is

a. to accelerate the reaction b. to control the reaction c. to absorb excessive neutrons d. to liberate excessive neutron

182. During load shedding

a. system voltage is reduced b. some loads are switch off c. system power factor is changed d. system frequency is reduced

183. A low utilization factor for a plant indicates that

a. plant is used for base load only b. plant is used for standby purpose only c. plant is under maintenance d. plant is used for peak load

184. Which of the following relations is incorrect?

a. Capacity factor = Utilization factor x Load factor b. Load factor x Maximum load = Average load c. Demand factor x Connected load = Maximum demand d. None of the above

185. When paralleling a generating unit to a power system, if the synchroscope indicates that

the incoming machine is running slower than the system: a. The field current should be increased b. The power input to the prime mover should be increased slightly c. The power input to the prime mover should be decreased slightly d. The synchronizing switch should be closed just after it indicates zero phase angle

difference.

186. When load on a thermal unit is increased, fuel input

a. Increased b. Does not change c. Decreased d. slightly decreased

187. When generating units are loaded to equal incremental cost:

a. Minimum fuel cost result b. Fuel cost at a maximum c. Fuel cost are not affected d. efficiency decreased

188. In a power system using both Hydro and thermal generation, the proportion of hydro

generation can be increased by. a. Increasing the price of water b. Reducing the price of water c. Increasing the field current of the Hydro generators d. Used salt water

189. Which of the following methods of generating electric power from the sea is more

advantageous? a. Water power b. Ocean power c. Tidal power d. sea power

190. The efficiency of a thermal power plant improves with.

a. increased quantity of coal burnt b. Use of high steam pressure c. Lower load on the plant d. Larger quantity of water used

191. A Gas turbine works on

a. Carnot cycle b. Brayton cycle c. Dual cycle d. Rankine cycle

192. Air standard efficiency of a diesesl engine depends on

a. compression ratio b. speed c. fuel d. torque

193. Most of the heat generated in internal combustion engine is lost in

a. cooling water b. exhaust gases c. lubricating oil d. radiation

194. Capital cost per MWh is highest in case of

a. steam power plant b. Diesel engine c. Nuclear power plant d. Hydroelectric

195. A diesel power plant is best suited as

a. stand by power plant b. base load plant c. peak load plant d. general purpose plant

196. A Nuclear Power plant is invariably used as a

a. base load plant b. peak load plant C. stand by plant d. spinning reserve plant

197. Economizers are used to heat

a. air b. feedwater c. steam d. boiler

198. Surge tank is provided for the protection of

a. weir b. penstock c. blade d. intake pipe

199. A generating station has a connected load of 43 MW an a maximum demand of 20 MW,

the units genetrated being 61.5 x 10 6 per annum. Calculate. The load factor. a. 64.8% b. 76% c. 351. % d 17.9%

200. For the same maximum demand, if the load factor is decreased the cost of energy is

a. increased b. decreased c. not affected d. no relation