Spring Test 5 due 4/26/2013

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1 Spring Test 5 due 4/26/2013 Multiple Choice Identify the choice that best completes the statement or answers the question. 1. Where fixed multioutlet assemblies are employed, each feet or fraction thereof of each separate and continuous length shall be considered as one outlet of not less than 180 volt-amperes where the connected appliances are unlikely to be used simultaneously. a. 5 b. 6 c. 8 d. 10 e The principal determinants of operating temperature are. I. heat generated internally in the conductor as the result of load current flow II. the rate at which generated heat dissipates into the ambient medium III. adjacent load-carrying conductors IV. ambient temperature a. II & IV only c. I, II & IV only e. I, II & III only b. I & IV only d. I, II, III & IV f. III & IV only 3. The maximum allowable ampacity of a 750 kcmil XHHW aluminum conductor is amps when there are six current carrying conductors in the raceway, the raceway is installed in a wet location, and the ambient temperature surrounding the raceway is 22 degrees C a b c d Where reduced heating of the conductors results from motors operating on duty-cycle, intermittently, or from all motors not operating at one time, the feeder conductors a. are not allowed to have the ampacity reduced b. may have an ampacity less than specified if acceptable to the authority having jurisdiction c. must be sized not smaller than 125% of the largest motor connected to the feeder d. must be sized not smaller than 125% of the largest motor plus other loads 5. A conductor has a computed ampacity of 75 amps. What is the maximum standard ampere rating of the overcurrent protection device the NEC permits to protect this circuit? This is not a motor circuit or part of a multioutlet branch circuit supplying receptacles. a. 70 amperes b. 75 amperes c. 80 amperes d. 85 amperes 6. If a circuit breaker serves as the controller for a motor, and the motor is not in sight of the breaker, the NEC requires the. a. motor to be less than 2 hp b. breaker be able to be locked in the open position c. motor to be Code letter E d. breaker to have an interrupting rating of 25,000 A 7. shall be placed in all service-entrance motor control centers to isolate service busbars and terminals from the remainder of the motor control center. a. Barriers b. Switches c. Isolators d. Conductors e. Markers 8. Coaxial cable shall be permitted to deliver power to equipment that is directly associated with the radio frequency distribution system if the voltage is not over volts and if the current is supplied by a transformer or other device that has power-limiting characteristics. a. 90 b. 25 c. 70 d. 60 e Among the conductors listed below, all except are permitted to be connected in parallel.

2 a. 250 kcmil b. 2/0 AWG c. 1 AWG d. 1/0 AWG 10. What is the demand load for eighty receptacles located in a 15,000-square-foot office building? a. 180 b. 12,200 c. 14,400 d. 15, The ampacity of conductors is derated when the ambient temperature exceeds ºF. a. 30 b. 72 c. 86 d Communications wires and cables shall be separated at least inches from conductors of any electric light, power, Class 1, non power-limited fire alarm, or medium-power network-powered broadband communications circuits. a. 4 b. 6 c. 24 d. 2 e The installation of a fire alarm system requires a plenum cable to be run above the lay-in ceilings. Which of the following cable types is acceptable? I. CMR II. CMP III. FPLR IV. FPLP a. III or IV only c. I, II, or III only e. III only b. I or III only d. I, II, III, or IV f. II or IV only 14. Where motors are provided with terminal housings, the housings shall be and of substantial construction. I. nonmetallic II. metal a. either I or II b. II only c. I only d. neither I nor II 15. The ampacities provided by the NEC for conductors volts are based on temperature alone and do not take into consideration. a. insulation b. AWG c. CMA d. voltage drop 16. Listed communications cables installed in risers shall be. a. encased in a metal raceway b. located in a fireproof shaft having firestops at each floor c. either a or b d. neither a nor b 17. When conductors of different systems are installed in the same raceway, one system grounded conductor shall be white or gray. The other system grounded conductor shall be. a. green only b. white with an identifying colored stripe that is green c. white with an identifying colored stripe that is not green d. white only 18. For a raceway containing 30 current carrying conductors, the ampacity of each conductor shall be reduced to percent of that for a single conductor. a. 80 b. 70 c. 45 d Which of the following statements about a 2 AWG THHN copper conductor is correct? a. its maximum operating temperature is 90 C b. it has a nylon insulation c. its area is square inches d. it has a DC resistance of ohms per m/ft. 20. A motor control circuit. I. carries electric signals to the controller and carries the main power II. does not carry electric signals to the controller but does carry the main power III. carries the electric signals to the controller but does not carry main power

3 a. I only b. II only c. III only d. none of these 21. What is the area, in square inches, of a 8 AWG bare conductor in a raceway? a b c d 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% 23. Thermoplastic insulated fixture wire shall be durably marked with the AWG size, voltage rating and other required markings on the surface at intervals not exceeding inches. a. 6 b. 12 c. 18 d The minimum number of 120-volt, 15-amp lighting branch circuits required for a dwelling that has ft. of livable space is. a. 2 b. 3 c. 4 d The grounded conductor, when insulated, shall have insulation. I. rated not less than 300 volts for solidly grounded neutral systems of 1 kv and over as described in section II. which is suitable, other than color, for any ungrounded conductor of the same circuit on circuits of less than 1000 volts a. I only b. II only c. either I or II d. neither I nor II 26. Determine the maximum current setting permitted for overload protection for a motor that has a thermal protector integral with the motor, given the following information. * 7 1 / 2 hp - wound rotor type * two-phase, 4 wire, AC * 230 volts a. 19 amps b amps c amps d amps 27. A nipple contains six 6 AWG THW copper current-carrying conductors. The ampacity of each conductor would be amperes. a. 65 b. 50 c. 52 d The minimum number of 20-amp, 277-volt, lighting circuits required for a 150,000 ft 2 department store is. The actual connected lighting load is 400 kva. Assume breakers are not rated for continuous use. a. 72 b. 82 c. 91 d For general motor application, the fuse size for the motor branch circuit must be determined from. a. motor nameplate current c. NEC Tables b. NEMA standards d. Factory Mutual 30. A code letter D is marked on a motor nameplate. What is its locked-rotor kva per horsepower? a b c d Where installed in raceways, conductors of size AWG and larger shall be stranded. a. 16 b. 12 c. 10 d. 8 e When calculating the total load on a dwelling, what is the minimum VA that must be added for the two required small-appliance circuits? a VA b VA c VA d VA 33. What is the full load current of a 30 hp, 230-volt, 3-phase, synchronous motor with a 90% power factor? a. 63 amps b amps c amps d amps 34. What is the VA input of a fully-loaded, 5 hp, 230-volt, single-phase motor?

4 a. 746 b. 3,730 c. 6,440 d. 12, For a nonautomatically started motor, the overload protection shall be permitted to be shunted or cut out of the circuit during the starting period of the motor if the device by which the overload protection is shunted or cut out cannot be left in the starting position and if fuses or inverse time circuit breakers rated or set at not over percent of the full-load current of the motor are located in the circuit so as to be operative during the starting period of the motor. a. 140 b. 115 c. 125 d. 130 e Which of the following is not true? a. A demand factor from Table could be applied to a household counter-mounted cooking unit of 1760 watts. b. Ten household clothes dryers have a demand factor of 50%. c. A demand factor from Table could be applied to a 1 3 / 4 kw wall-mounted oven. d. Table is permitted to be used for a branch circuit to a household range. 37. The demand factors of Table apply to the computed load of feeders to areas in hospitals, hotels, and motels where the entire lighting is likely to be used one at a time, as in operating rooms, ballrooms, or dining rooms. a. shall b. shall not 38. Communications cables permitted where installed in vertical runs and penetrating more than one floor, or cables installed in vertical runs in a shaft, shall be Type. I. CMP II. CMG III. CMR a. I only c. III only e. II only b. I or II only d. I, II, or III f. I or III only 39. Table in the 2011 edition of the NEC is used as a reference for underground installations of network-powered broadband communications conductors and cables. a b c d When calculating the load for show window lighting, shall be included for this load. a. 120 VA per outlet c. 200 VA per linear ft. b. 280 VA per outlet d. 180 VA per linear ft. 41. optical fiber cables contain optical fibers and current-carrying electrical conductors. a. Composite b. Nonconductive c. Conductive 42. When using the optional calculation method for a dwelling unit service, all other loads above the initial 10 kw are to be listed at. a. 40% b. 50% c. 60% d. 75% 43. For a dwelling unit served by a single set of 3-wire, 120/240-volt or 208Y/120-volt service-entrance conductors with an ampacity of or greater, it is permissible to compute the feeder and service loads in accordance with (B) and (C) instead of the method specified in Part III of Article 220. a. 175 b. 125 c. 150 d Equipment terminations are permitted to be used with higher temperature-rated conductors at the ampacity of the higher-rated one, provided the equipment is and identified for use with the higher rated conductors. a. listed b. tested c. installed d. rated 45. The grounded conductor of a branch circuit that is 6 AWG or smaller shall be. I. without splices II. white or gray in color a. I only b. neither I nor II c. both I & II d. II only

5 46. Open conductors shall be supported on glass or porcelain knobs,. I. strain insulators II. brackets III. racks a. I only b. II only c. III only d. I, II or III 47. A previously unwired portion of an existing residence or a structural addition to an existing residence, either of which exceeds square feet, shall be computed in accordance with sections and a. 100 b. 250 c. 300 d Synchronous motors of the low-torque, low-speed type, such as are used to drive reciprocating compressors, pumps, and so forth, that start unloaded, do not require a fuse rating or circuit-breaker setting in excess of percent of full-load current. a. 150 b. 200 c. 250 d Ampacity of fixture wire is determined. a. by referring to ampacity Table b. by calculation, using the expected temperature rise of the fixture c. from a table in Article 402 of the Code d. none of these 50. When installing a fire alarm system, survivability cable is typically used in a. a. single-story office building c. hospital b. restaurant d. school 51. The disconnecting means for motor circuits rated 600 volts, nominal, or less, shall have an ampacity rating of at least % of the FLC rating of the motor. a. 100 b. 115 c. 125 d. 135 e Conductors for a motor used in a short-time, intermittent, periodic, or varying duty application shall have an ampacity of not less than the percentages of the motor nameplate current ratings shown in Table. I II III (B) IV (E) a. II only c. I only e. I or II only b. III only d. IV only f. III or IV only

6 Spring Test 5 due 4/26/2013 Answer Section MULTIPLE CHOICE 1. ANS: A 2011 NEC: (H)(1) REF: 2011 NEC: (H)(1) OBJ: Obj Worksheet NAT: Obj ABank 2. ANS: D 2011 NEC: (A)(3) I-Note No.1 & (1) thru (4) REF: 2011 NEC: (A)(3) I-Note No.1 & (1) thru (4) OBJ: Obj Worksheet NAT: Obj ABank 3. ANS: A 385 A 80% 1.05 = amps 2011 NEC: T (B)(2)(a); T (B)(3)(a) & T (B)(16) REF: 2011 NEC: T (B)(2)(a); T (B)(3)(a) & T (B)(16) 4. ANS: B 2011 NEC: REF: 2011 NEC: OBJ: Obj Worksheet 5. ANS: C 2011 NEC: 240.4(B)(2)&(3) & 240.6(A) REF: 2011 NEC: 240.4(B)(2)&(3) & 240.6(A) OBJ: Obj Worksheet 6. ANS: B 2011 NEC: (B) Exc REF: 2011 NEC: (B) Exc OBJ: Obj Worksheet 7. ANS: A 2011 NEC: (E) REF: 2011 NEC: (E) OBJ: Obj Worksheet 8. ANS: D 2011 NEC: REF: 2011 NEC: OBJ: 434 NEC Worksheet 9. ANS: C 2011 NEC: (H)(1) REF: 2011 NEC: (H)(1) NAT: Obj ABank

7 10. ANS: D VA = 14,400 [(10,000) 100%] + [(14,400 10,000) (50%)] = 10, ,200 = 12,200 VA versus 1 VA/SF SF = 15,000 VA 2011 NEC: (K); ; T ; (I) REF: 2011 NEC: (K); ; T ; (I) OBJ: Obj Worksheet NAT: Obj ABank 11. ANS: C 2011 NEC: T (B)(16) REF: 2011 NEC: T (B)(16) OBJ: Obj Worksheet 12. ANS: D 2011 NEC: (A)(2) REF: 2011 NEC: (A)(2) OBJ: 434 NEC Worksheet 13. ANS: F 2011 NEC: T (D) REF: 2011 NEC: T (D) OBJ: Obj Worksheet NAT: Obj ABank 14. ANS: B 2011 NEC: (A) REF: 2011 NEC: (A) 15. ANS: D 2011 NEC: (A)(1) I-Note No. 1 REF: 2011 NEC: (A)(1) I-Note No. 1 OBJ: Obj Worksheet 16. ANS: C 2011 NEC: ; T (a) REF: 2011 NEC: ; T (a) OBJ: 434 NEC Worksheet 17. ANS: C 2011 NEC: 200.6(D) REF: 2011 NEC: 200.6(D) NAT: Obj ABank 18. ANS: C 2011 NEC: (B)(3) I-Note No. 2 REF: 2011 NEC: (B)(3) I-Note No. 2 OBJ: Obj Worksheet 19. ANS: A 2011 NEC: T (A) REF: 2011 NEC: T (A) OBJ: Obj Worksheet NAT: Obj ABank 20. ANS: C

8 2011 NEC: REF: 2011 NEC: OBJ: Obj Worksheet 21. ANS: B 2011 NEC: Ch 9-Table 8 & (C) REF: 2011 NEC: Ch 9-Table 8 & (C) NAT: Obj ABank 22. ANS: C 2011 NEC: (B)(1) REF: 2011 NEC: (B)(1) OBJ: Obj Worksheet 23. ANS: D 2011 NEC: 402.9(A) REF: 2011 NEC: 402.9(A) NAT: Obj ABank 24. ANS: C ( VA) = 6,300 VA 6, = 52.5 amps = circuits 2011 NEC: T REF: 2011 NEC: T OBJ: Obj Worksheet 25. ANS: B 2011 NEC: 200.2(A) REF: 2011 NEC: 200.2(A) NAT: Obj ABank 26. ANS: C 2011 NEC: T with (A)(2) REF: 2011 NEC: T with (A)(2) 27. ANS: A 2011 NEC: (B)(3) I-Note No. 2(2) REF: 2011 NEC: (B)(3) I-Note No. 2(2) 28. ANS: C Per (A), the connected load is used over the demand load when known. Lighting load is continuous, therefore use 125% (1.25) 400, = 500,000 VA 500, = 1,805 amps 1, = ckts 2011 NEC: (A)(1) & (A)

9 REF: 2011 NEC: (A)(1) & (A) OBJ: Obj Worksheet NAT: Obj ABank 29. ANS: C 2011 NEC: 430.6(A)(1) & (C)(1) REF: 2011 NEC: 430.6(A)(1) & (C)(1) 30. ANS: D 2011 NEC: T (B) REF: 2011 NEC: T (B) OBJ: Obj Worksheet 31. ANS: D 2011 NEC: (C) REF: 2011 NEC: (C) OBJ: Obj Worksheet NAT: Obj ABank 32. ANS: D 2011 NEC: (A) REF: 2011 NEC: (A) OBJ: Obj Worksheet 33. ANS: B Due to 90% power factor = NEC: T REF: 2011 NEC: T ANS: C 2011 NEC: T REF: 2011 NEC: T ANS: E 2011 NEC: (A) REF: 2011 NEC: (A) 36. ANS: C 2011 NEC: ; T REF: 2011 NEC: ; T OBJ: Obj Worksheet 37. ANS: B 2011 NEC: T *Note (below table) REF: 2011 NEC: T *Note (below table) OBJ: Obj Worksheet NAT: Obj ABank 38. ANS: F 2011 NEC: & T (a) REF: 2011 NEC: & T (a) OBJ: 434 NEC Worksheet 39. ANS: A 2011 NEC: (C)

10 REF: 2011 NEC: (C) OBJ: 434 NEC Worksheet 40. ANS: C 2011 NEC: (G)(2) REF: 2011 NEC: (G)(2) OBJ: Obj Worksheet NAT: Obj ABank 41. ANS: A 2011 NEC: REF: 2011 NEC: OBJ: 434 NEC Worksheet 42. ANS: A 2011 NEC: (B) REF: 2011 NEC: (B) 43. ANS: D 2011 NEC: (A) REF: 2011 NEC: (A) OBJ: Obj Worksheet 44. ANS: A 2011 NEC: REF: 2011 NEC: ANS: D 2011 NEC: 200.6(A)(1) & (2) REF: 2011 NEC: 200.6(A)(1) & (2) NAT: Obj ABank 46. ANS: D 2011 NEC: REF: 2011 NEC: NAT: Obj ABank 47. ANS: D 2011 NEC: (A)(1) REF: 2011 NEC: (A)(1) OBJ: Obj Worksheet 48. ANS: B 2011 NEC: T Note 3 REF: 2011 NEC: T Note 3 OBJ: Obj Worksheet 49. ANS: C 2011 NEC: REF: 2011 NEC: ANS: C Best guess general knowledge REF: Gen Knowledge OBJ: Obj Worksheet

11 NAT: Obj ABank 51. ANS: B 2011 NEC: (A) REF: 2011 NEC: (A) OBJ: Obj Worksheet 52. ANS: D 2011 NEC: (E) REF: 2011 NEC: (E) OBJ: Obj Worksheet

Spring Test 9 due 05/11/2013

Spring Test 9 due 05/11/2013 Multiple Choice Identify the choice that best completes the statement or answers the question. 1. A grounding electrode is. a. a solid conductor b. a circuit conductor that