Republic of the Philippines PROFESSIONAL REGULATION COMMISION Manila BOARD OF ELECTRICAL ENGINEERING Registered Master Electrician Licensure Examination PHILIPPINE ELECTRICAL CODE
INSTRUCTION: Select the answer for each of the following questions. Mark only the answer for each item by shading the box corresponding to the letter of your choice on the answer sheet provided. STRICTLY NO ERASURES ALLOWED. Use pencil no. 1 only.
MULTIPLE CHOICE 1.
Derating factors factors do not apply to conductors in conduit having a length not exceeding a. 300 mm b. 400 mm c. 500 mm d. 600 mm 2
2. If the ampacity of the same 3 – 8 mm THW copper conductors inside raceway is 45 amperes at an ambient temperature of 30 degree centigrade then the ampacity of such conductors at an ambient temperature of 40 degree centigrade is (the correction factor is 0.88) a. 36.75 b 33.75 c. 36.9 d. 39.6 3.
A 4 kW, 230 volts, three phase wound rotor induction induction motor has a rated full load efficiency of 85 % and power factor of 75 %. The maximum rating of the inverse time time delay circuit breaker for branch circuit protection is: a. 47 A b. 30 A c. 40 A d. 42 A
4.
According to the table of operating voltage in the code. The minimum conductor size for copper conductor for 8000 v is a. 8.0 sq mm b. 2.0 sq mm c. 3.5 sq mm d. 5.5 sq mm
5.
According to the table of operating voltage in the code. The thickest insulation for conductor size copper conductor is. a. 8.0 sq mm b. 2.0 sq mm c. 3.5 sq mm d. 5.5 sq mm
6.
The minimum minimum size of wire wire used in electrical wiring is the former number 14 AWG. Under the metric system now shown the new PEC, the diameter is, a. 1.6 mm b. 2 mm c. 2.6 mm d. 3.2 mm
7. The minimum minimum size of the service entrance conductor using THW copper wire is is 2 2 2 2 a. 14 mm b. 8 mm c. 22 mm d. 5.5 mm 8.
According to the table of operating voltage in the code. The minimum conductor size for copper conductor for 15,000 v using AWG system is. a. 2 b. 12 c. 1 d. 0
9.
The unit lighting for bank if the actual no of receptacle is unknown is expressed expressed in VA per square meter shall be; a. 8 VA b. 28 VA c. 36 VA d. 40 VA
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10. For the kitchen small appliance load in occupancies, the code requires not less than; a. two 20 A circuits b. one 15 A circuit c. two 15 A circuits d. one 20 A circuit 11. To provide for small appliance load in dwelling units, the feeder should be computed at; a. 1,500 watts b. 3,000 watts c. 2,400 watts d. 3,600 watts 12. The service or feeder capacity necessary to provide for six 5-kW household electric clothes dryer is; a. 18 kW b. 24 kW c. 19.5 kW d. 21 kW 13. For service-drop conductors not exceeding 600 volts its minimum clearance over residential property and driveways, and those commercial areas not subject to truck traffic. a. 3,100 mm b. 3,700 mm c. 4,600 mm d. 5,500 mm 14. For service drop conductors not exceeding 600 volts its minimum clearance over public streets, alleys, roads, parking areas subject to truck traffic, driveways on other than residential property and other land traversed by vehicles such as cultivated, grazing, forest, and orchard. a. 3,100 mm b. 3,700 mm c. 4,600 mm d. 5,500 mm 15. Conductors must have a clearance from windows, porches, fire escapes of not less than; a. 700 mm b. 800 mm c. 900 mm d. 1,000 mm 16. Service conductors passing over roof must have a clearance over the roof which they pass of not less than a. 1,000 mm b. 2,500 mm c. 1,500 mm d. 3,000 mm 17. The minimum clearance for service drops over buildings. a. 1,000 mm b. 2,500 mm c. 1,500 mm
d. 3,000 mm
18. The minimum clearance for service drops over side walks. a. 2,500 mm b. 3,100 mm c. 5,500 mm
d. 3,700 mm
19. The minimum clearance of service drops over driveway, alleys, and public roads. a. 3,100 mm b. 5,500 mm c. 4,600 mm d. 3,700 mm 20. When the voltage between service conductors does not exceed 300 volts and the roof has a slope of not less than 100 mm in 300 mm, the clearance can be reduced to; a. 600 mm b. 800 mm c. 900 mm d. 1000 mm 21. What position must a knife switch with fuse be mounted? a. horizontal b. vertical c. diagonal 22. What is the maximum voltage rating of plug fuses? a. 110 volts b. 125 volts c. 200 volts
d. inclined position
d. 220 volts
23. For each 2-wire laundry branch circuit, a feeder load of NOT less than _____ shall be included. a. 1,800 VA b. 1,500 VA c. 2,000 VA d.1,200 VA 24. Why are system and circuit grounded? a. To protect from excessive current b. To limit the excess voltage to ground, which occur from lightning or exposure to other higher voltage source. c. To acquire more power from grounding circuit
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d. Precautionary measure of the system 25. Code requires that the minimum area exposed surface offered by a plate electrode shall be; a. 1/8 sq. meter b. ¼ sq. meter c. 3/8 sq. meter d. ½ sq. meter 26. A single grounding electrode is permitted when the resistance to ground does not exceed; a. 5 Ω b. 10 Ω c. 15 Ω d. 25 27. The minimum size of a copper equipment grounding conductor required for equipment connected to a 40-ampere circuit. a. 5.5 sq. mm b. 8 sq. mm c. 14 sq. mm d. 22 sq. mm 28. Open wiring on insulators commonly known as; a. knob and tube wiring c. Duplex wiring
b. Split knob and receptacle wiring d. Common wiring
29. The circuit conductors between the service entrance equipment or isolated generating plant and the branch circuit overload device or devices. a. feeder b. disconnecting switch c. overcurrent protector d. secondary conductors 30. Is a contact device installed at the outlet for the connection of a single attachment plug. a. switch b. receptacle c. male plug d. bulb 31. What is the maximum number of bends (in degrees) permitted in rigid metal conduit between outlets. a. 180 b. 360 c. 45 d. 75 32. What should you do to prevent shock when working on a high voltage power supply? a. charge the filter capacitor b. open the filter capacitor c. closed the filter capacitor d. discharge the filter capacitor 33. Gas manufacturing plant where flammable gases may escape is considered as; a. Class I, Division 1 area b. Class I, Division 2 area c. Class II, Division 1 area d. Class II, Division 2 area 34. A storage battery supplying emergency lighting and power shall maintain not less than 87.5 percent of full voltage at total load for a period of at least; a. 2.5 hours b. 2 hours c. 1.5 hours d. 1.0 hour 35. GFCI operate on currents of 5 mA b. 3 mA
c. 10 mA
36. A buck-boost transformer is classified as a. Compensating reactor c. High density lamp
b. Autotransformer d. Ramset
d. 15 A
37. When surge occurs a potential of 10,000 volts would exist between the CATV system and the electrical system and between the grounded conductor within the CATV cable and the grounded surfaces in the walls of the home, such as water pipes (which are connected to the power ground), over which the cable runs. What could be the possible effect to the persons on a direct contact with the CATV. a. This potential could also appear across a person with one hand on the CATV cable and the other hand on a metal surface connected to the power ground (e.g., a radiator or refrigerator). b. A voltage dip might occur between the power conductor
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c. There is an additional voltage drop in the conductor due to surge impedance of the line d. An electromagnetic Interference occur 38. The point of attachment of the service-drop conductors to a building or other structure shall provide the minimum clearances as specified in the code. In no case shall this point of attachment be less than ________ above finished grade. a. 2500 mm b. 3700 mm c. 2850 mm d. 3000 mm 39. Where the voltage between conductors does not exceed 300 and the roof has a slope of 100 mm in 300 mm, or greater, a reduction in clearance to _______shall be pe rmitted. a. 1000 mm b. 900 mm c. 450 mm d. 550 mm 40. Which of the following is a short circuit? a. a hot wire touching a grounded metal frame b. a short conductor with a high resistance c. arcing between a hot conductor and a metal box d. a very low resistance between the circuit conductors 41. In a Three phase four wire system, compose of lighting and motor load, demand factor of 70 percent is permitted for that portion of the neutral load in excess of _____ amperes. a. 100 b. 200 c. 300 d. 400 42. Communication, radio, and television coaxial cables shall be permitted at a height of not less than ______ above swimming and wading pools, diving structures, and observation stands, towers, or platforms. a. 8.0 m b. 3.0 m c. 1.0 m d. 0.5 m 43. Conductors on poles shall have a separation of not less than ________ where not placed on racks or brackets. a. 300 mm b. 500 mm c. 1000 mm d. 150 mm 44. Reasonable efficiency of operation can be provided when ______ is taken into consideration in sizing the service-lateral conductors. a. mechanical strength b. ambient temperature c. voltage drop d. none of these 45. For a feeder supplying household cooking equipment and electric clothes dryers the maximum unbalanced load on the neutral conductor shall be considered as ______ of the load on the ungrounded conductors. a. 40% b. 50% c. 70% d. 80% 46. There would be an additional heating due to other conductors in the duct. This is due to. a. skin effect b. Kelvin effect c. proximity effect d. edge effect 47. Which of the following is the maximum allowable rating of a permanently connected appliance where the branch overcurrent device is used as the appliance disconnecting means? a. 1/8 hp b. ¼ hp c. ½ hp d. 1 hp 48. How would you seal unused ko’s in panels and boxes? a. cardboard b. duct seal c. tape d. metal plugs and plates 49. Where conductors are adjusted to compensate for voltage drop, equipment grounding conductors, where required, shall be adjusted proportionally according to __________. a. diameter b. cross section area
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c. circular mil area
d. circumference
50. Line and ground connecting conductors shall not be smaller than 2.0 sq mm copper or 3.5 sq mm aluminum. The arrester grounding conductor shall be connected to one of the following except for. a. Grounded service conductor b. Grounding electrode conductor of 25 ohms or higher c. Grounding electrode for the service d. Equipment grounding terminal in the service equipment
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