Lecture 6 Wiring Methods

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Shop Pract

ice with

Electrical Code:

Wiring Methods

Jayson Bryan E. Mutuc, REE, RME Jayson Bryan E. Mutuc, REE, RME

BSEE-PUP BSEE-PUP

MSEE, Major in Power Systems -MIT (candidate) MSEE, Major in Power Systems -MIT (candidate)

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Chapter 3 Wiring Methods and

Materials

Article 3.0 Wiring Methods Article 3.0 Wiring Methods

3.0.1.3 3.0.1.3 ConductorConductorss (b) conductors of the (b) conductors of the same circuit (p.306) same circuit (p.306)

All conductors of the All conductors of the same circuit and, where used , same circuit and, where used , the grounded conductor and all the grounded conductor and all equipment grounding

equipment grounding conductorsconductors and bonding conductors shall be and bonding conductors shall be contained within the same

contained within the same

raceway, auxiliary gutter, cable raceway, auxiliary gutter, cable tray, cable bus assembly, trench tray, cable bus assembly, trench cable or cord unless otherwise cable or cord unless otherwise permitted.

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3.0.1.3 (b) Conductor

s of

the Same

Circuit

3

3..00..11..33 ((bb))((11)) PPaarraalllleelleedd Installations

Installations C

Coonndduuccttoorrss sshhaallll bbee p

peerrmmiitttteedd ttoo bbee rruunn iinn ppaarraalllleell iinn aaccccoorrddaannccee wwiitthh tthhee pr

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3.0.1.3 (C) Conductors of Different

Systems (p.307)

3 3..00..11..33 ((cc))((11)) 660000 VVoollttss,, N

Nomomininalal,, oror LLesess.s. C

Coonndduuccttoorrss ooff cciirrccuuiittss rraatteedd 660000 vvoollttss nnoommiinnaall oorr le

lessss,, aacc ccirirccuuititss,, aandnd ddcc cciirrccuuititss,, sshhaallll bbee ppeerrmmiitttteedd ttoo ooccccuuppyy ssaammee eeqquuiippmmeenntt wwiirriinngg e

enncclloossuurree,, ccaabbllee oorr rraacceewwaayy.. A

Allll ccoonndduuccttoorrss sshhaallll hhaavvee aann iinnssuullaattiioonn rraattiinngg eeqquuaall ttoo aatt lleeaasstt tthhee mmaaxxiimmuumm cciirrccuuiitt v

voollttaaggee aapppplliieedd ttoo aannyy ccoonndduuccttoorr wwiitthhiinn tthhee en

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3.0.1.10 Electrical Continuity of Metal

Raceways and Enclosure (p.317)

A

Allll mmeettaall rraacceewwaayyss,, ccaabbllee,, b

booxxeess,, ffiittttiinnggss,, ccaabbiinneettss,, aanndd e

enncclloossuurreess ffoorr ccoonndduuccttoorrss m

muusstt bbee mmeettaalllliiccaallllyy jjooiinneedd ttooggeetthheerr ((bboonnddeedd)) ttoo ffoorrmm aa ccoonnttiinnuuoouuss llooww--iimmppeeddaannccee ffaauulltt--ccuurrrreenntt ppaatthh tthhaatt iiss ccaappaabbllee ooff ccaarrrryyiinngg aannyy ffaauulltt ccuurrrreenntt lliikkeellyy ttoo bbee iimmppoosseedd oonn it.

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3.0.1.12 Mechanical

Continuity-Raceways and Cables (p.319)

Raceways and Cables (p.319)

M

Meettaall oorr nnoonnmmeettaalllliicc rraacceewwaayyss,, ccaabbllee aarrmmoorrss,, aanndd ccaabbllee sshheeaatthhss sshhaallll bbee cconontitinunuououss bebetwtweeeenn ccaabibinenetsts,, b

booxxeess,, ffiittttiinnggss,, oorr ootthheerr en

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3.0.1.13 Mechanical and Electrical

Con

tinu

tinuity-

ity-

Cond

uct

uctor

ors (p.3

s (p.3

19)

3.0.1.13(a) General.

Conductors in

Conductors in racewaraceways shallys shall be continuous between

be continuous between

outlets, boxes, devices, and so outlets, boxes, devices, and so forth. There shall be no splice forth. There shall be no splice or tap withi

or tap within a raceways unlessn a raceways unless permitted by 3.0.1.15; permitted by 3.0.1.15; 3.68.2.47(a); 3.76.2.47; 3.68.2.47(a); 3.76.2.47; 3.78.2.47; 3.84.2.47; 3.86.2.47; 3.78.2.47; 3.84.2.47; 3.86.2.47; 3.88.2.47; or 3.90.1.6 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 Poin

ts (p.319)

At least

At least 150 mm150 mm _{of free}_{of free}

conductor, measued from the conductor, measued from the

point in the box where it emerges point in the box where it emerges from its raceway or cable sheath, from its raceway or cable sheath, shall be left at each outlet,

shall be left at each outlet, junction box, and switch po

junction box, and switch point forint for splices or ther connection of

splices or ther connection of luminaires (fixtures) or devices. luminaires (fixtures) or devices. Where the opening to an outlet, Where the opening to an outlet, junction, or switch point is less junction, or switch point is less

than

than 200 mm200 mm _{in any dimension,}_{in any dimension,}

each conductor shall be long each conductor shall be long enough to extend at least

enough to extend at least 75 mm75 mm

outside the opening outside the opening

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3.0.1.15 Box

es, Conduit Bodies,

or Fittings

_–

Where Required (p.320)

A box must be installed at each A box must be installed at each splice or termination point,

splice or termination point, excep

except as t as permitted for:permitted for: • Cabinet or

• Cabinet or Cutout BoxCutout Boxes,es, 3.12.8 3.12.8 • Conduit Bodies, • Conduit Bodies, 3.14.16(C)3.14.16(C) • • Luminaires, 4.10.31Luminaires, 4.10.31 • Surface Raceways, • Surface Raceways, 3.86.563.86.56 and 3.88.56 and 3.88.56

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3.0.1.15 Box

es, Conduit Bodies,

or Fittings

_–

Where Required (p.320)

3.0.1.15(i) Enclosure

A

A bbooxx oorr ccoonndduuiitt bbooddyy isn’t

isn’t rreeqquuiirreedd wwhheerree aa sspplliiccee iiss m

maaddee iinn aa ccaabbiinneett oorr iinn ccuuttoouutt b

booxxeess ccoonnttaaiinniinngg sswwiittcchheess oorr ov

overercucurrrrenentt prprototecectitionon dedevivicecess iiff tthhee sspplliicceess oorr ttaappss ddoo nnoott ffiillll tthhee wwiirriinngg ssppaaccee aatt aannyy ccrroossss sseeccttiioonn ttoo mmoorree tthhaann 7755 p

peerrcceenntt,, aanndd tthhee wwiirriinngg aatt aannyy ccrroossss sseeccttiioonn doesn’tdoesn’t exceedexceed 40

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3.0.1.20 Induced Currents in Metal Enclosure or

Metal Raceway (p.324)

3.0.1.20 (A) Conductors 3.0.1.20 (A) Conductors Group

Grouped ed TTogethogetherer.. T

Too mmiinniimmiizzee iinndduuccttiioonn h

heeaattiinngg ooff ffeerrrroouuss mmeettaalllliicc rraacceewwaayyss aanndd eenncclloossuurreess,, aanndd ttoo mmaaiinnttaaiinn aann eeffffeeccttiivvee g

grroouunndd--ffaauulltt ccuurrrreenntt ppaatthh,, aallll ccoonndduuccttoorrss ooff aa cciirrccuuiitt mmuusstt bbee iinnssttaalllleedd iinn tthhee ssaammee rraacceewwaayy,, ccaabbllee,, ttrreenncchh,, ccoorrdd,, oorr ccaabbllee