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MULTIVECTORPrepared By: In television system, channels 2 to 13 are classified as _____. Ans. VHF Power in a three phase delta system with balanced load is equal to _____. Ans. √ 3 VL IL (p.) What is the maximum number of wattmeters required to measure unbalanced power for a three phase system? Ans. ...

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ELECTRICAL ENGINEERING OBJECTIVES MULTIVECTOR 1. In television system, channels 2 to 13 are classified as _____. Ans. VHF 2. Power in a three phase delta system with balanced load is equal to _____. Ans. √3 VL IL (p.f.)

13. Minimum clearance between the recessed incandescent fixture and the nearest point of a storage space of a closet is _____. Ans. 150 mm 14. Derating factor in each 7 to 9 conductors in a raceway is _____. Ans. 70 %

3. What is the maximum number of wattmeters 15. Maximum number of conductors in a raceway that required to measure unbalanced power for a three does not need to be derated is _____. phase system? Ans. 3 Ans. 2 4. Form factor is defined as _____. Ans. Rms value/average value

16. 34.5 kV to 69 kV is classified as _____. Ans. High voltage

5. The value of form factor for a pure sine wave is _____. Ans. 1.11

17. If the speed of an induction motor increases, what happens to the rotor frequency. Ans. Decreases

6. The basic function of a circuit breaker is to _____. Ans. Extinguish the arc

18. One advantage of distributing the winding in alternator is to _____. Ans. Improve voltage waveform

7. Air used in air blast circuit breaker _____. Ans. Must be free from moisture

19. If the voltage is doubled, the ampacity of a conductor _____. 8. The counterpart of magnetic flux in an electric Ans. Remains the same circuit is _____. 20. The purpose of a grid system is to _____. Ans. Current Ans. Interconnect the power stations 9. In a parallel circuit the potential difference across 21. As the load is increased the speed of a dc shunt the resistance _____. motor will _____. Ans. Is always constant Ans. Reduce slightly 10. The rms value of a sinusoidal wave is equal to _____ 22. If the field of a synchronous motor is under excited of maximum value. the power factor will be _____. Ans. 0.707 Ans. Lagging 11. In two wattmeter method, the readings of the 23. In dc machines, lap winding is used for _____. wattmeters will be identical when _____. Ans. Low voltage high current Ans. Power factor is unity 24. Wye-wye power transformers are protected by 12. Maximum distance between two receptacles in a current transformers having _____ connection. single family dwelling unit is _____. Ans. Delta-delta Ans. 1.8 m

Prepared By: SAMONTE, HERSHEY BABAGAY

CNSC BATCH 2017

ELECTRICAL ENGINEERING OBJECTIVES MULTIVECTOR 25. If supply voltage is changed by 5 % for a 3 phase 37. Temperature coefficient of a conductor is defined induction motor, its torque will have a change of as the _____. _____. Ans. Increase in resistance per ohm per degree centigrade Ans. 10 % 38. Open conductors run individually as service drops 26. What equipment is not part of a megger? shall be _____. Ans. A coil of high inductance Ans. Either insulated or bare 27. The armature current drawn by any dc motor is proportional to _____. Ans. The torqued required

39. The power factor of an alternator is determined by its _____. Ans. Load

28. Surge impedance of transmission line is given by _____. Ans. √L/C

40. The speed of a synchronous motor _____. Ans. Always remains constant

41. The efficiency of a thermal power plant is approximately _____. 29. For an unbalanced load, which connection is Ans. 30 % suitable? Ans. 4-wire wye connection 42. One advantage of distributing the winding in alternator is to _____. 30. The meter movement in an illumination meter Ans. Improve voltage waveform directly measures _____. Ans. Current 43. Impurities in an electrolyte can cause an internal short circuit condition called _____. 31. An electrical insulator can be made a conductor Ans. Local action _____. Ans. By ionizing it 44. The turn on voltage of a Ge junction diode is _____ volt. 32. To reverse the direction of rotation of a 3 phase Ans. 0.3 induction motor, it is necessary to _____. Ans. Interchange any two of the three line conductors 45. A mode of communication in which either party can hear while talking, thus allowing one party to 33. Transformers are rated in _____. instantly interrupt the other at any time, is called Ans. kVA _____. 34. In a series RL circuit, the inductor current _____ the Ans. Full duplex resistor current. 46. A device that repeatedly reverses the polarity of a Ans. Is equal to magnetic field in order to keep a dc motor rotating is known as _____. 35. The power factor of incandescent bulb is _____. Ans. Commutator Ans. Unity 47. Differential relay device function number assigned 36. The law that induces emf and current always by ANSI. opposes the cause producing them was discovered Ans. 87 by _____. Ans. Lenz 48. Wind mills in addition to proper gearing is the best driver for _____.

Prepared By: SAMONTE, HERSHEY BABAGAY

CNSC BATCH 2017

ELECTRICAL ENGINEERING OBJECTIVES MULTIVECTOR Ans. Induction generators

Ans. D

49. The dc generator that is used as pilot exciter is 61. Electrical safety month of the year is _____. _____. Ans. May Ans. Flat compound 62. What produces reactive power? 50. Bundled conductors in EHV transmission lines Ans. Induction motor results to _____. Ans. Increase capacitance 63. Receptacle outlets shall be located above, but not more than _____ mm above the countertop. 51. The surge impedance of an underground cable is Ans. 450 mm around _____. Ans. 25 Ω 64. In dwelling units, hallways of _____ m or more in length shall have at least one receptacle outlet. 52. A contact device installed at the outlet for the Ans. 3 connection of a single attachment plug. Ans. Receptacle 65. Time constant of a series RL circuit is equal to _____. 53. When carrier wave is modulated at 100 %, its power Ans. L/R is increased by _____ %. Ans. 50 % 66. Heating effect of current has undesirable side effect in _____. 54. Differential relays are installed to protect the Ans. Vacuum cleaner equipment against _____. Ans. Internal faults 67. A change of 5 % in the supply voltage of a 3 phase induction motor will produce to its torque a change 55. This is the porcelain insulator for the end poles. of approximately _____. Ans. Suspension Ans. 10 % 56. Farad is equivalent to what unit. Ans. Coulomb/volt 57. What is used in power factor correction? Ans. Synchronous motor

68. In two wattmeter method, the reading of the wattmeters will be identical when _____. Ans. Power factor is unity 69. An electric current can be neither _____ nor _____. Ans. Seen, touched

58. The lighting load for a dwelling expressed in terms of a unit load in volt ampere per sq. meter must be 70. In transmission voltage levels, 765 kV is categorized at least _____. as _____. Ans. 24 Ans. Extra high voltage 59. What do you call the interior lighting where the roof 71. Purpose of a grid system is to _____. trusses or ceiling height is greater than 7.6 m above Ans. Interconnect the power stations floor level. Ans. High mast 72. Efficiency of a thermal plant. Ans. 30 % 60. Which of the following is a vector quantity? a. magnetic flux c. magnetic reluctance 73. The number of parallel paths in a simplex lap b. magnetic flux density d. magnetic field intensity winding is equal to _____. Prepared By: SAMONTE, HERSHEY BABAGAY

CNSC BATCH 2017

ELECTRICAL ENGINEERING OBJECTIVES MULTIVECTOR Ans. Number of poles

85. The barrier potential for a silicon diode at 250 C is approximately _____. Ans. 0.7 V

74. If the input of the prime mover of an alternator is kept constant but the excitation is increased then _____. 86. Ten oersted is equivalent to _____. Ans. kVA will be lagging Ans. 10 Gb/cm 75. The useful life of a diesel engine in a power plant is expected to be _____ years. Ans. 15

87. Which ammeter is the most sensitive? Ans. 0-1 micro ammeter

88. Brushes of dc machine are usually made of _____. 76. An automatic device that operates at preset values Ans. Carbon is known as _____. Ans. Relay 89. Impurities in an electrolyte can cause an internal short circuit condition called _____. 77. Magnetic field exists around _____. Ans. Local action Ans. Moving charges 90. What is the minimum number of wattmeters 78. The applied voltage is increased by 50 % and required to measure unbalanced power for a three frequency is reduced by 50 %. The maximum core phase system? flux density will become _____. Ans. 2 Ans. 3 times 91. Permeance is analogous to _____. 79. Surge impedance of transmission line is given by Ans. Conductance _____. 92. Overvoltage relay device function number. Ans. √L/C Ans. 59 80. What is not a type of the contactor for circuit 93. A test used to determine the equivalent resistance breakers? of an induction motor is _____. Ans. Vacuum Ans. Blocked-rotor test 81. Charging lead acid cell causes the electrolyte to 94. Unit of retentivity. become _____. Ans. Ampere turn/weber Ans. Stronger 95. In running condition the rotor reactance of 3 phase 82. If the resistance of the field winding of a dc induction motor is proportional to _____. generator is increased the output voltage will Ans. Slip _____. Ans. Decrease 96. The ratio of total flux to useful flux is called _____. 83. Wye-wye power transformers are protected by Ans. Leakage factor current transformers having _____ connection. 97. With reduction of load on alternator _____. Ans. Delta-delta Ans. The frequency increases 84. Luminous intensity of a lamp is expressed in _____. 98. The process by which metallic parts are Ans. Candela demagnetized is called _____. Ans. Degaussing Prepared By: SAMONTE, HERSHEY BABAGAY

CNSC BATCH 2017

ELECTRICAL ENGINEERING OBJECTIVES MULTIVECTOR 99. The gas inside the inner discharged tube of a Ans. 40o mech. sodium vapor lamp is _____. Ans. Neon 111. Moving coil instruments are used _____. Ans. In dc circuits only 100. What is the nature of the current flowing in the armature of dc machine? 112. Efficiency of thermal plant is approximately Ans. Alternating current _____. Ans. 30 % 101. Which of the ff frequencies has the longest period? 113. Merz-Price protection is used on _____. a. 1 Hz c. 1 kHz Ans. Substations b. 10 Hz d. 100 kHz Ans. A 114. The greater percentage of materials are _____. 102. If one of the resistors in a parallel circuit is Ans. Paramagnetic removed, what happens to the total resistance? Ans. Increases 115. The greatest percentage of power loss in dc motor is due to _____. 103. Purpose of using oil in transformer. Ans. Copper loss Ans. Cooling and insulation 116. The charge of a hole is _____. 104. Skin effect is proportional to _____. Ans. Equal to that of a proton Ans. (diameter of conductor)2 117. Transient current in an RLC circuit is 105. The three primary colors in the oscillatory when _____. chrominance signal of a color TV are _____. Ans. R < 2√L/C Ans. Red, green, blue 118. As load pf of an alternator becomes more 106. An alternator running in parallel with other leading, the value of the generated voltage required alternators all having automatic voltage regulators to give rated terminal voltage _____. is to be taken off the bus. The usual procedure Ans. Decreases before opening the switch is to _____. Ans. Reduce the power fed to the prime mover 119. This device is used to reflect back surges into the line. 107. What is not one of the relays in Ans. Choke coil transmission line? Ans. Negative sequence relay 120. Some of the arrangement for switch/panel boards are as follows, except _____. 108. The area of hysteresis loop is the measure Ans. Vertical of _____. Ans. Energy loss per cycle 121. If a 440 V heater is used on 110 V supply, heat produced by it will be as _____ much. 109. Slip rings are made of _____. Ans. 1/16 Ans. Copper 122. The fuse used for the overhead primary 110. In a winding of a 3 phase, 6 pole induction distributors is _____. motor, the space angle between two consecutive Ans. Expulsion phases is _____. Prepared By: SAMONTE, HERSHEY BABAGAY

CNSC BATCH 2017

ELECTRICAL ENGINEERING OBJECTIVES MULTIVECTOR 123. Porcelain insulators are protected against 134. When a welding transformer is used in a creepage of surge current by the use of _____. resistance welding, it will _____. Ans. Arcing horns Ans. Step up current 124. This is the lighting system wherein the 135. Grounding allows _____ opposition path of percentage of upward and downward brightness is current flow. the same. Ans. Low Ans. General diffuse 136. When the temperature of the wire 125. One ampere-turn is equivalent to _____ increases, what happens to the resistance? gilberts. Ans. Increases Ans. 1.26 137. What is the maximum allowable continuous 126. What motor is used to start heavy loads? load for branch circuit conductor? Ans. Series Ans. 0.8 127. The capacitor in a capacitor start induction 138. In PEC 1, where does a bonding jumper is run ac motor is connected in series with _____ connected? winding. Ans. Equipment enclosure Ans. Starting 139. For a series circuit the current flowing is 128. Power circuit breakers can be classified _____. according to operation, some of these are, except Ans. Same in all components _____. Ans. Inclined break 140. What is the primary advantage of FM over AM? 129. The lowest KAIC available commercially for Ans. Noise immunity miniature circuit breakers is _____. Ans. 5 141. Floor receptacles outlets are not counted unless they are within a distance of _____ mm from 130. This is the least prevalent shunt fault the wall. among transmission and distribution lines. Ans. 450 mm Ans. LLL 142. A permanent split single phase capacitor 131. In what year was the first 500 kV line in the motor does not have _____. world became operational? Ans. Centrifugal switch Ans. 1965 143. The sparking at the brushes of a dc 132. If starting voltage of a SCIM is reduced to 50 generator is due to _____. % of its rated value, torque developed is reduced by Ans. Reactance voltage _____ % of its full load value. Ans. 75 144. Buchhoiz relay is a _____. Ans. Gas actuated device 133. A standard cable emits a total luminous flux of _____ lumens. 145. Electrical continuity is required by the PEC Ans. 12.57 for metallic conduit _____. Ans. To assure equipment grounding Prepared By: SAMONTE, HERSHEY BABAGAY

CNSC BATCH 2017

ELECTRICAL ENGINEERING OBJECTIVES MULTIVECTOR 146. The turn on voltage of a Ge junction diode is _____ volt. Ans. 0.3

157. All circuits must be protected against _____. Ans. Overload and short circuit

147. Is the overall energy program formulated 158. Which of the following is not a standard and updated yearly by the DOE, submitted to classification for a branch circuit supplying several congress pursuant to RA 7638. loads? 30 A, 20 A, 40 A and 25 A Ans. Energy plan Ans. 25 A 148. In a resistance welding, the SCR is closed during _____ time. Ans. Squeeze, weld and hold

159. Based on PDC, what interruption events is included in the calculation of distribution utility indices? Ans. Outages on 34.5 kV lines

149. For a hermetic motor compressor, how many percent of the full load current is the 160. In a resistance welding, the pneumatic allowable rating for branch disconnecting means? pressure is applied during _____ time. Ans. 115 Ans. Squeeze, weld and hold 150. What is the difference between a 161. Is also known as cold standby reserve. refrigerator and an air conditioner? Ans. Contingency reserve Ans. A refrigerator takes away heat from a refrigerated space while an air conditioner takes away heat from a living 162. The commonly used light sensor in a space. modern fax machine is the _____. Ans. Charge couple device 151. In TV transmission, picture signal is _____ modulated. 163. Which is/are permitted for branch Ans. Amplitude disconnecting means of a second building? I. Inside the building near service entrance 152. Device function number of a directional II. Outside the building but accessible power relay. Ans. I and II Ans. 32 164. The correct word to define wiring which is 153. With reduction of load in alternator _____. not concealed is _____. Ans. The frequency increases Ans. Exposed 154. Transformer taps are generally on the 165. What is the barrier potential of a silicon _____ of transformer. diode at room temperature? Ans. High voltage winding Ans. 0.7 V 155. A thermal protection switch is able to 166. When luminaires direct 90 to 100 % of their protect a circuit against _____. output upward is considered a _____. Ans. Overload Ans. Indirect lighting 156. Minimum height of service drop conductors 167. The primary function of a fuse is to _____. above a driveway is _____ mm. Ans. Protect the line Ans. 3,700 168. A type of electronics communication in which only one party transmits at a time. Prepared By: SAMONTE, HERSHEY BABAGAY

CNSC BATCH 2017

ELECTRICAL ENGINEERING OBJECTIVES MULTIVECTOR Ans. Half duplex

180. Current reactors are used to _____. Ans. Bring down the fault level within the capacity

169. The parameters for a parallel RLC circuit are 1 ohm, ½ H and ½ F. Determine the type of damping 181. Heating effect of current has undesirable exhibit by the circuit. effects in _____. Ans. Under damped Ans. Vacuum cleaner 170. The commonly used light sensor in a modern fax machine is the _____. Ans. Charge couple device

182. The minimum size of copper conductor for a 230 volt general illumination branch circuit in a dwelling is _____ mm2. Ans. 2.0

171. Device function number of an ac circuit breaker. 183. Overcurrent protection responds to _____. Ans. 52 Ans. Increase in current above the pick-up value 172. What power plant cannot have a single unit 184. If the dc current is reversed in the control of 100 MW? winding of a saturated reactor _____. Ans. Diesel power plant Ans. Same ac current will flow 173. What is the full load efficiency of a power 185. The overcurrent protective device is caused transformer? to operate by _____. Ans. 0.98 Ans. Current flow 174. A/an _____ relay that operates or pick-up 186. Luminaire type permitted in clothes closets. when its current exceeds a pre-determined value. Ans. Surface mounted or recessed incandescent fixture with Ans. Over current a completely enclosed lamp. 175. _____ are auxiliary transformers used for 187. When electrons build up pressure at one metering or operation of auxiliary equipment and point it is called _____. relays. Ans. Current flow Ans. Current transformers 188. Fermi energy is the amount of energy which _____. 176. A gain of 106 times is expressed by _____. Ans. 60 dB Ans. Must be given to an electron to move it to conduction band 177. An electrical outlet constructed so that moisture will not enter the enclosure is classified as 189. A gang capacitor is a variable capacitor in being _____. which capacitance is varied by changing the _____. Ans. Watertight Ans. Plate area 178. What common electronic components is not found in ICs? Ans. Inductors 179. What is the maximum number of quarter bends permitted in rigid conduits between outlets? Ans. 4 Prepared By: SAMONTE, HERSHEY BABAGAY

190. Which of these in not an objective of GRID planning? a. Generating capacity c. Type of circuit b. Timing d. Voltage Ans. B

CNSC BATCH 2017

ELECTRICAL ENGINEERING OBJECTIVES MULTIVECTOR 191. In the differential current protection Ans. Vacuum system, the current transformer secondaries of wye-delta power transformers will be in _____. 202. An energy of 10.152 x 1018 J is equal to Ans. Delta-wye _____ quad. Ans. 9.623 192. The amount of frequency deviation from the center of frequency in an FM transmitter is 203. A fuse is a _____ device. proportional to the _____. Ans. 1-phase thermal Ans. Amplitude 204. What is not a factor in the selection of fuse 193. _____ time is the total time it takes a fuse rating for protection of a branch circuit? to interrupt a circuit at a certain fault current level. Ans. System impedance Ans. Total clearing 205. A _____ is an electrical device that prevents 194. The varmeter, in conjunction with other an electrocution caused by an accident or meter device can be used to determine the _____ equipment malfunction. factor. Ans. Ground fault circui...