Lecture 6 Wiring Methods

Shop Practice Practice with Electrical Code: Wiring Methods Jayson Bryan E. Mutuc, REE, RME BSEE-PUP MSEE, Major in Power Systems -MIT (candidate)

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Chapter 3 Wiring Methods and Materials Article 3.0 Wiring Methods 3.0.1.3 Conductors Conductors (b) conductors of the same circuit (p.306) All conductors of the same circuit and, where used , the grounded conductor and all equipment grounding conductors and bonding conductors shall be contained within the same raceway, auxiliary gutter, cable tray, cable bus assembly, trench cable or cord unless otherwise permitted. 2

3.0.1.3 (b) Conductors Conductors of the Same Circuit 3.0.1.3 (b)(1) Installations

Paralleled

Conductors shall be permitted to be run in parallel in accordance with the prov provis isio ion n of 3. 3.10 10.1 .1.4 .4

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3.0.1.3 (C) Conductors of Different Systems (p.307) 3.0.1.3 (c)(1) 600 Volts, Nomin ominal al,, or Les ess. s. Conductors of circuits rated 600 volts nominal or les less, ac circ ircuits its, and dc circuits its, shall be permitted to occupy same equipment wiring enclosure, cable or raceway. All conductors shall have an insulation rating equal to at least the maximum circuit voltage applied to any conductor within the enclo enclosu sure re,, cabl cable, e, or racew acewa ay.

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3.0.1.10 Electrical Continuity of Metal Raceways and Enclosure (p.317) All metal raceways, cable, boxes, fittings, cabinets, and enclosures for conductors must be metallically joined together (bonded) to form a continuous low-impedance fault-current path that is capable of carrying any fault current likely to be imposed on it.

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3.0.1.12 Mechanical ContinuityRaceways and Cables (p.319) Metal or nonmetallic raceways, cable armors, and cable sheaths shall be conti ontinu nuou ouss betw betwee een n cabine binets ts,, boxes, fittings, or other encl enclos osur ures es or outl outlet ets. s.

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3.0.1.13 Mechanical and Electrical Continu Con tinuityity- Cond Conduct uctor orss (p.319) (p.319) 3.0.1.13(a) General. Conductors in raceways raceways shall be continuous between outlets, boxes, devices, and so forth. There shall be no splice or tap within withi n a raceways unless permitted by 3.0.1.15; 3.68.2.47(a); 3.76.2.47; 3.78.2.47; 3.84.2.47; 3.86.2.47; 3.88.2.47; or 3.90.1.6

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3.0.1.14 Length of Free Conductors at Outlets, Junctions, and Switch Points Points (p.319) At least 150 mm of free conductor, measued from the point in the box where it emerges from its raceway or cable sheath, shall be left at each outlet,  junction box, and switch point point for splices or ther connection of luminaires (fixtures) or devices. Where the opening to an outlet,  junction, or switch point is less than 200 mm in any dimension, each conductor shall be long enough to extend at least 75 mm outside the opening

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3.0.1.15 Boxes, Boxes, Conduit Bodies, or Fittings  – Where Required (p.320) A box must be installed at each splice or termination point, except except as permitted for: • Cabinet or Cutout Boxes, Boxes, 3.12.8 • Conduit Bodies, 3.14.16(C) • Luminaires, 4.10.31 • Surface Raceways, 3.86.56 and 3.88.56 • Wireways, 3.76.56

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3.0.1.15 Boxes, Boxes, Conduit Bodies, or Fittings  – Where Required (p.320) 3.0.1.15(i) Enclosure A box or conduit body isn’t required where a splice is made in a cabinet or in cutout boxes containing switches or over overcu curr rren entt prot protec ecti tion on devi device cess if the splices or taps do not fill the wiring space at any cross section to more than 75 percent, and the wiring at any cross section doesn’t exceed 40 per percent. ent. See See 3. 3.12 12.1 .1..8

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3.0.1.20 Induced Currents in Metal Enclosure or Metal Raceway (p.324) 3.0.1.20 (A) Conductors Grouped Group ed Together ogeth er.. To minimize induction heating of ferrous metallic raceways and enclosures, and to maintain an effective ground-fault current path, all conductors of a circuit must be installed in the same raceway, cable, trench, cord, or cable tray.

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