Spring Test 15 due 06/14/2013 Multiple Choice Identify the letter of the choice that best completes the statement or answers the question. ____ ____ ____ ____ ____ ____ ____ ____ ____ ____ 1. Surface mounted fluorescent luminaires (lighting fixtures) that contain a ballast and are to be installed on combustible, low density cellulose fiberboard should be spaced not less than how many inches from the surface of the fiberboard? a. 1/2 (13mm) c. 1-1/2 (38mm) b. 1 (25mm) d. 2 (50mm) 2. Which of the following statements about lightning protection is (are) true? I. If lightning protection is required for an irrigation machine, a driven ground rod should be connected to the machine at a stationary point. II. Lightning rods should be spaced at least 6 feet (1.8m) away from noncurrent-carrying metal parts of electrical equipment. a. I only c. both I and II b. II only d. neither I nor II 3. Which of the following percentages of conduit fill should be used when four Type THW conductors are being installed? a. 55% c. 40% b. 53% d. 31% 4. A capacitor is located indoors. It must be enclosed in a vault if it contains more than a minimum of _____ gallon(s) of flammable liquid. a. 1 c. 3 b. 2 d. 5 5. The allowable distance between supports of nonmetallic-sheathed cable installed in an on-site, constructed one-family dwelling is a maximum of how many feet? a. 750mm (2-1/2) c. 1.2m (4) b. 900mm (3) d. 1.4m (4-1/2) 6. Which of the following statements about dimmers installed in theaters is (are) true? I. Dimmers installed in ungrounded conductors must have overcurrent protection not greater than 125% of the dimmer rating. II. The circuit-supplying autotransformer type dimmers must not exceed 150 volts between conductors. a. I only c. both I and II b. II only d. neither I nor II 7. The interrupting rating shall be marked on all circuit breakers that have ratings other than____. a. 100 amperes c. 2500 amperes b. 2000 amperes d. 5000 amperes 8. Each doorway that leads into a transformer vault from the building interior should have a tight-fitting door with a minimum fire rating of how many hours? a. 1 c. 3 b. 2 d. 5 9. Except for points of support, recessed portions of luminaire (lighting fixture) enclosures not rated for insulation contact should be spaced at least how many inches from combustible material? a. 1/4 (6mm) c. 1 (25mm) b. 1/2 (13mm) d. 3 (75mm) 10. Snap switches can be grouped or ganged in outlet boxes if voltages between adjacent switches do not exceed how many volts? ____ 11. ____ 12. ____ 13. ____ 14. ____ 15. ____ 16. ____ 17. ____ 18. ____ 19. ____ 20. ____ 21. ____ 22. a. 200 c. 400 b. 300 d. 500 The demand load for four or more fixed appliance grouped into a special appliance load is found by adding wattage ratings from the appliance nameplates and multiplying the total wattage (volt-amps) by_____. a. 65% c. 80% b. 75% d. 100% ® The most recent editions of the NEC are revised every____. a. year c. 3 years b. 2 years d. 4 years Excluding fuses and exceptions, how many overcurrent protection devices, such as trip coils, relays or thermal cutouts, are required on a 3-phase motor? a. 5 c. 2 b. 3 d. 0 The minimum amount of on-site fuel for an emergency generator should be sufficient for not less than____. a. 2 hours at full demand c. 6 hours at 50% demand b. 4 hours at 75% demand d. 8 hours at 25% demand Ground-fault protection of equipment is a requirement for solidly grounded wye services that are rated at more than 150 volts-to-ground but do not exceed 600 volts, phase-to-phase, for each service disconnecting means rated at 1000 amperes or more. The maximum amperage for this ground-fault protection relay should be set at ______. a. 1000 amps c. 1500 amps b. 1200 amps d. 2000 amps An underground service to a small, controlled water heater is to be installed. The single branch-circuit used for this service requires that copper conductors be at least_____. a. 12 AWG c. 8 AWG b. 10 AWG d. 6 AWG Liquidtight flexible metal conduit can be used in which of the following locations? a. in areas that are both concealed and c. in connection areas for gasoline exposed dispensing pumps b. in areas that are subject to physical d. in areas where ambient temperature is to damage be greater the 200ºC Unless otherwise indicated, busways should be supported at intervals not to exceed how many feet? a. 3 c. 7 b. 5 d. 10 Flexible 18 AWG supply cords of listed appliances are considered adequately protected if the circuit over-current device is set at a maximum value of how many amperes? a. 15 c. 30 b. 20 d. 40 The general lighting load for a dwelling unit shall be determined by multiplying the square footage by______VA. a. 1 c. 3 b. 2 d. 4 The minimum number of receptacles in a patient bed location of a hospital’s general care area should be_____. a. 1 duplex c. 3 duplex b. 2 duplex d. 3 single Where conductors of less that 600 volts emerge from the ground, they must be protected by enclosures or raceways that extend from below grade to a point how many feet above the finish grade? a. 1.5m (5) c. 2.1m (7) ____ 23. ____ 24. ____ 25. ____ 26. ____ 27. ____ 28. ____ 29. ____ 30. ____ 31. ____ 32. ____ 33. ____ 34. b. 1.8m (6) d. 2.4m (8) Which of the following will effectively ground a 230-volt, single phase, residential portable air-conditioning unit that replaces an older unit supplied by a 2-wire, 230-volt circuit? I. A new circuit containing a grounding conductor. II. An 8-foot (2.5m) ground rod installed at the unit. a. I only c. both I and II b. II only d. neither I nor II An area must be classed as a Class II hazardous location if it contains which of the following? a. combustible dust c. ignitable liquids b. flammable gases d. ignitable vapors When it is impractical to locate a service head directly above the point of attachment, the maximum allowable placement distance from the point of attachment is how many feet? a. 1 (300mm) c. 3 (900mm) b. 2 (600mm) d. 4 (1.2m) An insulated bushing is required to be used on a raceway entering a cabinet if the ungrounded conductors entering the raceway are at least______. a. 10 AWG c. 6 AWG b. 8 AWG d. 4 AWG The maximum number of quarter bends allowed in one run of nonmetallic rigid conduit is___. a. 2 c. 6 b. 4 d. 8 All of the following sizes of solid aluminum conductors shall be made of an aluminum alloy except_____. a. 8 AWG c. 12 AWG b. 10 AWG d. 14 AWG The minimum size intermediate metal conduit required for the installation of the following conductors should not be less than______. 2 - 500kcmil THW phase A and B conductors 1 - 400kcmil THW neutral conductor 1 - 300kcmil THW phase C conductor 1 - 3/0 AWG THW ground conductor a. 2” c. 3” b. 2-1/2” d. 3-1/2” At least two small appliance circuits are required to supply receptacle outlets located in the____. a. kitchen c. dining room b. pantry d. all of the above It is permissible to use 4 THW CU AWG for service in dwelling units to a maximum load of_____. a. 100 amperes c. 70 amperes b. 95 amperes d. 65 amperes Which of the following terms can be used in place of “resistance” in the phrase “ resistance is to ohms”? a. reactance c. impedance b. inductance d. capacitance Surge arrester grounding conductors that run in metal enclosures should be___. a. bare c. bonded on one end of the enclosure only b. insulated d. bonded at both ends of the enclosure A metal raceway system installed in the washing area of a car wash must be spaced at least how far from the walls? a. 1/8” (3mm) c. 3/4” (19mm) b. 1/4” (6mm) d. 1” (25mm) ____ 35. The conduit run between warm and cold locations should be____. a. sealed c. insulated b. sleeved d. provided with drains ____ 36. If three resistors with values of 5, 10, and 15 ohms, respectively, are connected in parallel, the combined resistance of the units will be_____. a. 1.63 ohms c. 20.0 ohms b. 2.73 ohms d. 30.0 ohms ® ____ 37. The NEC requires a minimum of which of the following for the kitchen small-appliance load in dwelling units? a. two 20-ampere circuits c. one 20-ampere circuit b. two 15-ampere circuits d. one 15-ampere circuit ____ 38. The attachment plug and receptacle can be used as the controller for a portable motor that has a maximum horsepower rating of____horsepower. a. 1/3 c. 1 b. 1/2 d. 2 ____ 39. The maximum size of flexible metal tubing that can be used in any construction or installation is_____. a. trade size 12 (3/8) c. trade size 21 (3/4) b. trade size 16 (1/2) d. trade size 27 (1) ____ 40. Illumination is mandatory for service equipment or panelboards in a dwelling unit if the service to the unit exceeds how many amperes? a. 100 c. 400 b. 200 d. required for all services regardless of amperage ____ 41. Using 1” conduit, solve how many conduit seals are required for the following scenario: A remote paneleboard conduit feeds the first gas pump, which then has a conduit feeding a second gas pump, the second gas pump has a conduit that feeds a third gas pump, and the third gas pump has a conduit going to a light pole. a. 2 c. 6 b. 4 d. 8 ____ 42. The number of overcurrent devices in a single cabinet of a panelboard should not exceed______. a. 30 c. 42 b. 36 d. its design ____ 43. If the wiring is to placed 18 inches (450mm) above the floor, which of the following wiring methods is prohibited for a commercial automotive repair shop? a. metal-clad cable c. rigid nonmetallic conduit b. electrical metallic tubing d. nonmetallic-sheathed cable ____ 44. The combined load of several 240-volt, fixed space heaters on a 20-ampere circuit should not exceed how many kilowatts? a. 2.4 c. 3.8 b. 2.6 d. 4.8 ____ 45. The demand load for a household dryer shall be calculated by the nameplate rating or _____kVA, whichever is greater. a. 2 c. 4 b. 3 d. 5 ® ____ 46. Then NEC covers the installation of electrical conductors and equipment in all of the following locations, except____. a. public and private buildings c. buildings used by a utility for warehousing b. floating dwelling units d. centers of transmission and distribution of electrical energy ____ 47. Service conductors that pass over rooftops should have a vertical clearance of not less than how many meters/feet? a. 900mm (3) c. 2.4m (8) b. 2.1m (7) d. 3.0m (10) ____ 48. The service rating for a residence that uses 2 AWG THW copper service-entrance conductors is____. a. 95 amperes c. 115 amperes b. 110 amperes d. 125 amperes ____ 49. In the NEC, which of the following is the most acceptable grounding electrode? a. a driven steel approved ground rod d. an underground cold water metal piping system b. well casing e. any of these c. building foundation steel ____ 50. Service conductors can have less than 3 feet (900mm) of clearance from which of the following? a. doors c. fire escapes b. tops of windows d. porches ____ 51. When connected to a rod, pipe, or plate grounding electrode, grounding electrode copper conductors need not be sized larger than____. a. 8 AWG c. 4 AWG b. 6 AWG d. 2 AWG ____ 52. The heating and A/C load shall be calculated at_____percent and the smaller of the two dropped. a. 80 c. 125 b. 100 d. 150 Spring Test 15 due 06/14/2013 Answer Section MULTIPLE CHOICE 1. ANS: C 410.136(B) PTS: 1 2. ANS: C NEC Articles 675.15 and 250.106 (FPN) 2 PTS: 1 3. ANS: C NEC Chapter 9 Table 1 PTS: 1 4. ANS: C 460.2 PTS: 1 5. ANS: D Article 334.30 PTS: 1 6. ANS: C Article 520.25(A) and (C) PTS: 1 7. ANS: D NEC 240.83(C) PTS: 1 8. ANS: C NEC 450.43(A) PTS: 1 9. ANS: B 410.116(A) PTS: 1 10. ANS: B Section 404.8(B) PTS: 1 11. ANS: B NEC 220.53 PTS: 1 12. ANS: C Intro to the NEC PTS: 1 13. ANS: B Table 430.37 PTS: 1 14. ANS: A 700.12(B)(2) PTS: 1 15. ANS: B Article 230.95(A) PTS: 1 16. ANS: A NEC 230.31(B) excp PTS: 1 17. ANS: A Article 350.10 PTS: 1 18. ANS: B Section 368.30 PTS: 1 19. ANS: B NEC 400.13 and 240.5(A) PTS: 1 20. ANS: C NEC Table 220.12 PTS: 1 21. ANS: B 517.18(B) PTS: 1 22. ANS: D Section 300.5(D)(1) PTS: 1 23. ANS: A 440.3, 250.114(3)(A), 440.61 PTS: 1 24. ANS: A 500.5(C) PTS: 1 25. ANS: B Section 230.54(C) excp PTS: 1 26. ANS: D Section 300.4(G) PTS: 1 27. ANS: B Article 352.26 PTS: 1 28. ANS: D Section 310.106(B). 14 aluminum is not made PTS: 1 29. ANS: C Chapter 9, Tables 1, 4, and 5 PTS: 1 30. ANS: D NEC 210.11(C)(1) and 210.52(B)(1) PTS: 1 31. ANS: A Table 310.15(B)(7) PTS: 1 32. ANS: C General knowledge, Ugly’s PTS: 1 33. ANS: D NEC 280.25, 250.64(E) PTS: 1 34. ANS: B Section 300.6(D) PTS: 1 35. ANS: A Section 300.7(A) PTS: 1 36. ANS: B General knowledge, Ugly’s PTS: 1 37. ANS: A NEC 210.52, 210.11(C) PTS: 1 38. ANS: A Section 430.81(B) PTS: 1 39. ANS: C Article 360.20 PTS: 1 40. ANS: D Article 110.26(D) PTS: 1 41. ANS: D 501.15(A)(1) and (4) and (B) PTS: 1 42. ANS: D Section 408.54 PTS: 1 43. ANS: D Article 511.4(A)(1) PTS: 1 44. ANS: C 424.3(B) Max circuit kW = 4.8 Allowed @ 125% = 3.8 X 1.25 = 4.75kW PTS: 1 45. ANS: D NEC 220.54 PTS: 1 46. ANS: D Article 90.2(B) PTS: 1 47. ANS: C 230.24(A) PTS: 1 48. ANS: D Table 310.15(B)(7) PTS: 1 49. ANS: E Section 250.52(A) PTS: 1 50. ANS: B Article 230.9(A) excp PTS: 1 51. ANS: B Article 250.66(A) PTS: 1 52. ANS: B NEC 220.60 PTS: 1