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pleas help me in this do any question you know using National Electrical Code 2011

Applied Electricity NEC worksheet t hree Copper conductors with THHN insulation run in Electrical A branch-circuit Consther conductors. The conductor terminations are rated for a maximum ure in the area of this installation is not expected to exceed 30C size 8 AWG, the maximum ampacity of the conductors If the conductors for this circuit are permitted A 40 amperes. B. 50 amperes. to be used to determine the minimum conductor size is: C. 55 amperes. D. 60 amperes. E. 65 amperes Code reference ere, 120-volt branch-circuit consisting of Type UF Cable is supplied from the A 15-ampere, 120-volt service panel in a dwelling, and the entire circuit is protected with a GFCI burial cable supplies an unpaved drive used only for dwelling-related vehicles, shown in Figure 1.38. The cable is required to be buried to a minimum depth of A. 1ft (300 mm). B. 1.5 ft (450 mm). C 2 ft (600 mm). 2. a luminaire (lighting fixture) on a post in the yard, and is run under D. 3 ft (900 mm). E. 4 ft (1.2m). Code reference 3. Type MC Cable with three size 8 AWG copper conductors is run in a commercial building through metal studs in a wall. When terminating at a metal box, the cable is required to be supported a distance from the box of not more than: A. 1ft (300 mm). B. 1.5 ft (450 mm). D. 4.5 ft (1.4m). Code reference MINIMUM DEPTH UF Cable DWELLING Figure 1.38 Determine the minimum depth of burial required for Type UF Cable dwelling drive with circuit rated 15 amperes and GFCI protected under a 4. Type NM-B Cable enters a metal device box and is secured by a cable clamp at the bottom of the box. The cable is installed so the cable jacket extends "1/4 in. (6 mm beyond the cable clamp and free conductors begin at the end of the cable jacket shown in Figure 1.39. If the device box has a depth of 3.5 in. (90 mm), the minimum permitted length of free conductor in this box is required to be not less than: A. 3 in. (75 mm) B. 6 in. (150 mm). C. 6.5 in. (163 mm). D. 8 in. (200 mm). E. 12 in. (300 mm). Code reference 5. Type NM-B Cable is used in a dwelling as a switch loop from a ceiling box at a lighting outlet to a single-pole switch on the wall. A 120-volt, black, insulated conductor md a white, insulated neutral conductor are run using Type NM-B Cable to the ceiling box as shown in Figure 1.40. The white, insulated conductor from the ceiling box to the switch box: A is permitted to be either the 120-volt supply to the switch or the return to the light. B. is only permitted to be the return to the light. C if marked to identify it as an ungrounded conductor, is permitted to be the return to the light. D. is only permitted to be the return to the light and must be marked to identify it as an ungrounded conductor. E. is only permitted to be the 120-volt feed to the switch and must be permanently marked to identify it as an ungrounded conductor. Code reference TYPE NM-B CABLE. 12/2 WG GROUNDING WIRES TYPE NM-B CABLE LIGHTING OUTLET SWITCH Figure 1.40 Nonmetallic Sheathed Cable is used to wire a circuit containing a cei (lighting fixture) controlled by a single-pole wall switch submit a proposal to amend asection of the 2011 NEC, which may either by mail or fax at the NFPA become a part o office in Quincy. MA, not later than 5:00 PM EST on: e recerived D. May 15, 2007 A November 4, 2005. B. October 24, 2006. C. November 1, 2006. E. November 7, 2008. Code reference_ 7. The cross-sectional area of a size 8 AWG solid copper A 4110 cmil(2.08mm2). 8. 6530 cmil (3.31 mm2). 10,380 cmil (5.261 mm2). conductor is: Ce oela D. 16,510 cmil (8.367 mm2). E. 26,240 cmil (13.30mm2). Code reference 8. Type NM-B Nonmetallic-Sheathed Cable is required to be secured by staples, cable ties, straps, or similar fittings at intervals along the cable, shown in Figure 1.41, not exceeding 8ft(2.5 m).. 4.5 ft (1.4m). 0mm). C. D. 6 ft (1.8m). E. B.4 ft (1.2m). Code reference TYPE NM-B CABLE MAXIMUM DISTANCE Figure 1.41 Determine the maximum support spacing for Nonmetallic-Sheathed Cable run along the surface of a building. 1/0 AWG copper conductor without any markings to indicate the minimum terminal temperature rating temperature rating of the terminal is assumed to have a C. 60°C. D. 75c. The terminal for a size 9. E, 90-C. of: АЗОС 40°C Code reference_ rated branch-circuit supplies fluorescent luminaires (lighting fixtures) with a All terminations are 75"C rated, there are only three current- onductor insulation is THHW as shown in Figure 1.43. 10. A 20-ampere total load of 14.2 amperes. carrying conductors in EMT, and the c The minimum size copper conductor permitted for this branch-circuit is: A 16AWG C 12AWG. B. 14 AWG. D. 10 AWG. E. 8 AWG Code reference 11. Receptacles rated 120 volts and 15- or 20-amperes installed on construction sites for the e of supplying power for portable equipment are not permitted to be: A. of the grounding type. B. GFCI protected C. supplied with Type NM-B Cable if the building is more than three floors in height. D. supplied with Type NM-B Nonmetallic-Sheathed Cable for other than dwellings E. installed on branch-circuits that also supply temporary lighting. Code reference 12. An electrical panel is installed on a wall in a room of a commercial building where the distance from the floor to the structural ceiling is 15 ft (4.5 m). The distance from the floor to the top of the panelboard is 6 ft (1.8 m). An air-handling duct that will not cause dripping due to condensation is: A. permitted to be installed above the panelboard 8. permitted to be installed not less than 3 ft (900 m) above the panelboard. C. permitted to be installed not less than 4 ft (1.2 m) above the panelboard. D. permitted to be installed not less than 6 ft (1.8 m) above the panelboard. E. permited to be installed not less than 6 ft (1.8m) above panelboard Code reference TYPE SE-R CABLE MAXIMUM DISTANCE? Figure 1.44 Type SE style R Service-Entrance Cable is run along the flat surface of the interior of a building as a feeder to another location in the same building. 13. Type SE-R Service-Entrance Cable with three insulated conductors and a bare equipment grounding conductor contained within the outer nonmetallic sheath is used as a feeder to provide power from the service panel to a panelboard located in another part of the building as shown in Figure 1.44. The cable run along the flat surface of structural materials is required to be supported at intervals not to exceed: A 6 ft (1.8m). B. 41/2ft(1.4m) C. 3 ft (900 mm) D. 24 in. (600 mm) E. 12 in. (300 mm) Code reference 14. The National Electrical Code9 does not apply to wiring installations in: A underground mines. D. recreational vehicles. B. floating buildings. C. carnivals. E. public buildings. Code reference 15. Type UF Cable is installed as surface wiring in a building where damp conditions are likely to exist. The cable is used with nonmetallic boxes and fittings that prevent the entrance of moisture. The cable is required to be supported at intervals not to exceed: A 10 ft (3m). B. 6 ft (1.8m). C. 4 1/2ft(1.4m). D. 3 ft (900 mm). E. 24 in. (600 mm). Code reference WOOD STUD MINIMUM DISTANCE Figure 1.45 Type NM-B Nonmetallic-Sheathed Cable is run through bored holes in wood studs 16. Nonmetallic-Sheathed Cable, Type NM-B, ran through bored holes in wood studs in a dwelling, are only permitted to be installed without a metal plate protecting the cable from penetration by screws or nails if the distance from the edge of the hole shown in Figure 1.45, to the nearest edge of the stud is not less than: A. 3/4 in. (19 mm). B. 7/8 in. (22 mm) C. 1 in. (25 mm). D. I1/4 in. (32 mm) E. 2 in. (50mm). Code reference 17. A metallic 3 in. by 2 in. (75 mm by 50 mm) device box contains one 3-way switch. The cables entering the box are one Type NM-B size 14 AWG copper 2-conductor with equipment ground, and one Type NM-B size 14 AWG copper 3-conductor with equipment ground, as shown in Figure 2.32. The device box contains cable clamps. The minimum permitted box depth for this installation is: A. 2.25 in. (57 mm). B. 2.5 in. (65 mm). C. 2.75 in. (70 mm). D. 3.5 in. (90 mm). E. 4 in. (100 mm). Code reference 18. A single-gang nonmetallic box without cable clamps is used instead of the metallic box shown in Figure 2.32. The cables entering the box are one Type NM-B size 14 AWG copper 2-conductor with equipment ground, and one Type NM-B size 14 AWG copper 3-conductor with equipment ground. There is also a 3-way switch in the box. The minimum box volume permitted is: A. 14 in.3(229 cm2) 8. 15.75 in (258 cm), C. 16 in.3 (262 cm2). D. 18 in3(295 cm2). E. 20.25 in2(332 cm2). Code reference Figure 2.32 A 3-way switch is instalied in a metal device pox with size 14 AWG Type NM-B Cable entering both ends of the box. THREADED COUPLING IMC TRADE SIZE 1 (27) 900 MM) 3 FT SUPPORT MAXIMUM DISTANCE BOX Intermediate Metal Conduit is run exposed on the ceiling of a room. Figure 2.33 19. A straight run of trade size 1 (27) Intermediate Metal Conduit (IMC) is joined with threaded couplings and is supported within 3 ft (900 mm) of a box, as shown in Figure 2.33. The maximum distance permitted between supports of this straight run of IMC is: A10 ft (3m). D. 16 ft (4.9m) B.12 ft (3.7m). E. 20 ft (6.1m) C.14 ft (4.3 m) Code reference r size 4/0 AWG copper Type THWNco etailiConuit. The minimum trade size conduit 20. A feeder consists of fou Schedule 40 P permitted for this feeder is: A. trade size 1 (27). B. trade size 1.25 (35). C trade size 1.5 (41) Rigid Nonmetallic VC Type D. trade size 2 (53) E. trade size 2.5 (63). Code reference_ 21. A nonmetallic single-gang trade size 2 by 3 (50 by 75) box without installed in a wall of a new dwelling. The wiring method is Non Cable, Type NM-8 with a minimum of 4 in. of the cable sheath box. It is distance from the box measured along the cable of not more than: A. 3 in. (75mm) B. 4 in. (100 mm). С 6 in. (150 mm). cable clamps is metallic-Sheathed not required to secure the cable to this box if the cable is fastened within a D. 8 in. (200 mm). E. 12 in. (300mm). Code reference lay-in luminaires (lighting fixtures) are mounted in an accessible sus- from 20-ampere branch-circuits. Flexible Metal Conduit sugported by only a listed connector at a solidly mounted junction box and at the luminaire 22. Fluor rescent pended ceiling and supplied (lighting fixture) is permitted to be installed to supply a luminaire (fixture) in lengths not to exceed: A. 18 in. (450mm) B. 24 in. (600 mm) C. 3 ft (900 mm). D. 4 ft (1.2m) E. 6 ft (1.8m) Code reference 23. A pull box is installed with a trade size 4 (103) Electrical Metallic Tubing entering one end and leaving the opposite end. The conductors in the run of raceway are size 500-kcmil copper Type RHW. The minimum length of a pull box permitted for this installation is: A 12 in. (305 mm). B. 18 in. (457 mm). C. 24 in. (610mm). D. 30 in. (762 mm) E. 32 in. (812 mm). Code reference 24. A trade size 1 (27) Electrical Metallic Tubing is run acrass a ceiling perpendicular to the truss and attached to the bottom of the trusses as shown in Figure 2.38. The EMT is supported at ea luminaire (lighting fixture) and at each truss. The maximum permitted distance from the lumina (lighting fixture) to the first support is: A 18 in. (450mm) B. 3 ft (900 mm) C. 4 ft (1.2m) D. 5 ft (1.5m). 10 ft (3 m). E. Code reference D. trade size 1 1/2 (41). Atrade size 3/4 (21). B.trade size 1 (27). (53) Ctrade size 1 1/4(35). E. trade size 2 Code reference 29. The general use 125-volt receptacles in a commercial building are supplied by 20- ampere rated multiwire branch-circuits with three ungrounded conductors and a common neutral from a 208/120-volt, 4-wire, 3-phase electrical system. The con ductors for nine circuits are run in a single raceway to an area of the building includ ing nine ungrounded conductors and three neutral conductors. For the purpose of applying adjustment factors to determine the allowable ampacity of the conductors the number of current-carrying conductors for this set of circuits is: A. six. C. ten. E. sixteen. B. nine. D. twelve Code reference 30. A 140 ft (42.7 m) straight run of trade size 1 (27) PVC Type Rigid Nonmetallic Conduit is installed in an unheated parking structure where the temperature through out the year is likely to change up to 120"F (66.7°C). The change in length for this run of PVC Conduit over a season will be: A. 3.48 in. (88 mm). B. 4.87 in. (124 mm). С 5.12 in. (130mm). D. 5.84 in. (148 mm). E. 6.82 in. (173 mm). Code reference and 3 (78) conduit entering the adjacent side as shown in Figure 2.46 on the next page. Three size 4/0 AWG conductors run from the trade size 4 (103) to the trade size 3 (78) conduits. Three size 6 AWG and eight size 12 AWG conductors run from the trade size 4 (103) to the trade size 2 (53) conduits. The minimum distance per mitted from the trade size 3 (78) conduit to the opposite wall (dimension A) is: A 20 in. (521 mm) B. 22 in. (559 mm). C. 24 in. (618 mm) D. 26 in. (660 mm). E. 30 in. (762 mm). Code reference

Answer 1

1. The conductor terminal rated for a maximum of 75⁰C The maximum ampacity of the conductors permitted to be used to determine the minimum conductor size is 110 Amp for 60^O C terminal. But the temperature rating should be selected in such a way that the conductor ampacity does not exceed the lowest temperature rating of the connected terminal conductor or device.

2. Current 15A, voltage 120V branch circuit consists of Type UF Cable. The cable is required to be buried to a minimum depth of 24 inch which is equal to 2 ft. The cable is basically free from the cut or disturbed if it is located 2 ft below the ground.

3. The size of 8 AWG MC cable must be supported and secured at intervals of 6 ft of every termination.