2017 NEC Significant Code Changes Part 1

Transcription

1 2017 NEC Significant Cde Changes Part 1 Fur (4) Cntinuing Educatin Hurs Curse #EE1001 Apprved Cntinuing Educatin fr Prfessinal Engineers 2017 NEC Significant Cde Changes Part 1 i

2 Table f Cntents 2017 NEC Significant Cde Changes Part 1 Intrductin... 1 Article Chapter 1 General... 2 Article 100 Definitins... 2 Article 110 Requirements fr Electrical Installatins... 3 Chapter 2 Wiring and Prtectin... 6 Article 210 Branch Circuits... 6 Article 215 Feeders Article 220 Branch-Circuit, Feeder, and Service Calculatins Article 225 Outside Branch Feeders and Circuits Article 230 Services Article 240 Overcurrent Prtectin Article 250 Grunding and Bnding Chapter 3 Wiring Methds Article 300 Wiring Methds and Materials Article 310 Cnductrs fr General Wiring Article 312 Cabinets, Cutut Bxes, and Meter Scket Enclsures Article 314 Outlet, Device, Pull, and Junctin Bxes; Cnduit Bdies; Fittings; and Handhle Enclsures Article 320 Armred Cable: Type AC Article 324 Flat Cnductr Cable: Type FCC Article 336 Pwer and Cntrl Tray Cable: Type TC Article 344 Rigid Metal Cnduit: Type RMC Article 350 Liquidtight Flexible Metal Cnduit: Type LFMC Article 358 Electrical Metallic Cable: Type EMT Article 366 Auxiliary Gutters Article 370 Cablebus Quiz Questins NEC Significant Cde Changes Part 1 ii

3 2017 NEC Significant Cde Changes Part 1 LEARNING OBJECTIVES Upn cmpletin f this curse the student will be able t: 1. Becme familiar with sme f the significant changes including additins, deletins, and mdificatin t the 2017 Editin f NFPA 70: Natinal Electrical Cde (NEC) frm the 2014 Editin 2. Cmprehend, after reviewing the significant changes and additins t the 2017 Editin f NFPA 70: Natinal Electrical Cde (NEC) the large scpe f the changes t the cde, thereby seeking additinal and mre thrugh reviews f the entire cde, fllwing cmpletin f this curse. INTRODUCTION Every three years, the Natinal Electrical Cde (NEC ) is revised and expanded. Initially the NFPA received 4,012 public suggestins fr changes, which resulted in 1,235 first revisins. There were 1,513 public cmments submitted in respnse t these 1,235 first revisins, resulting anyne participating in the electrical industry t get up t speed with all the changes. What t Expect In this curse the student will be presented an verview f the mst significant changes fund in the 2017 NEC. This is part 1 f a series f curses cvering the changes and will prgress thrugh each chapter and its articles presenting the many imprtant changes. The changes will be highlighted fr easy recgnitin and a shrt synpsis f the reasn fr the change is presented as well. in 559 secnd revisins. Changes included editrial clarificatin, expanded requirements, new requirements, deleted requirements, and the relcatin f ther requirements. Nine new articles were prpsed, and five new articles were added t the 2017 NEC. With the fast pace f technlgy, it s mre imprtant than ever fr 2017 NEC Significant Cde Changes Part 1 1

4 Large-Scale Phtvltaic (PV) Electric Pwer Prductin Facility (New Article 691) cvers systems that prduce at least 5 megawatts (MW) f pwer, r enugh t pwer 800+ U.S. hmes. Energy Strage Systems (New Article 706) gverns ESS installatin, discnnectin, shutdwn, and safety labeling. Stand-Alne Systems (New Article 710) cvers pwer prductin surces that are nt cnnected t the grid, including PV and wind-pwered systems. Direct Current Micrgrids (New Article 712) cncerns independent energy distributin netwrks that allw the utilizatin f pwer frm dc surces t direct-current lads. Micrgrids are n the rise wrldwide ARTICLE 90 Intrductin 90.3 Cde Arrangement. This Cde is divided int the intrductin and nine chapters, as shwn in Figure Chapters 1, 2, 3, and 4 apply generally; Chapters 5, 6, and 7 apply t special ccupancies, special equipment, r ther special cnditins. These latter chapters and may supplement r mdify the general rules. requirements in Chapters 1 thrugh 7.4 apply except as amended by Chapters 5, 6, and 7 fr the particular cnditins. Chapter 8 cvers cmmunicatins systems and is nt subject t the requirements f Chapters 1 thrugh 7 except where the requirements are specifically referenced in Chapter 8. Chapter 9 cnsists f tables that are applicable as referenced. Infrmative annexes are nt part f the requirements f this Cde but are included fr infrmatinal purpses nly. CHAPTER 1 GENERAL ARTICLE 100 Definitins Accessible, Readily (Readily Accessible). Capable f being reached quickly fr peratin, renewal, r inspectins withut requiring thse t whm ready access is requisite t take actins such as t use tls (ther than keys), t climb ver r under, t remve bstacles, r t resrt t prtable ladders, and s frth. Infrmatinal Nte: Use f keys is a cmmn practice under cntrlled r supervised cnditins and a cmmn alternative t the ready access requirements under such supervised cnditins as prvided elsewhere in the NEC. Reasn fr the Change This revisin will cntinue t allw a panelbard cver t be lcked with a key while recgnizing that the vercurrent devices lcated behind the panelbard s perable lid r dr are still readily accessible. Assciated Apparatus [as applied t Hazardus (Classified) Lcatins]. Apparatus in which the circuits are nt necessarily intrinsically safe themselves but that affects the energy in the intrinsically safe circuits and is relied n t maintain intrinsic safety. Such apparatus is ne f the fllwing: (1) Electrical apparatus that has an alternative type f prtectin fr use in the apprpriate hazardus (classified) lcatin (2) Electrical apparatus nt s prtected that shall nt be used within a hazardus (classified) lcatin Reasn fr the Change The definitin f Assciated Apparatus was relcated t Article 100 fr applicatin acrss the hazardus lcatin NEC articles. The 2017 NEC Significant Cde Changes Part 1 2

5 additin f the wrds [as applied t Hazardus (Classified) Lcatins] will make it clear that the definitin pertains t Articles 500 thrugh 516 as applicable. Building. A structure that stands alne r that is cut ff separated frm adjining structures by fire walls with all penings therein prtected by apprved fire drs. Structure. That which is built r cnstructed, ther than equipment. Reasn fr the Change These terms were revised t eliminate Building Cde prvisins and t clarify that a structure is smething ther than equipment. Caxial Cable. A cylindrical assembly cmpsed f a cnductr centered inside a metallic tube r shield, separated by a dielectric material, and usually cvered by an insulating jacket. Reasn fr the Change The definitin f Caxial Cable was relcated t Article 100 t have an applicatin t ther articles acrss the NEC. Field Evaluatin Bdy (FEB). An rganizatin r part f an rganizatin that perfrms field evaluatins f electrical r ther equipment. [NFPA 790, 2012] Field Labeled (as applied t evaluated prducts). Equipment r materials t which has been attached a label, symbl, r ther identifying mark f an FEB indicating the equipment r materials were evaluated and fund t cmply with requirements as described in an accmpanying field evaluatin reprt. Reasn fr the Change These tw new definitins are necessary t recgnize a prcess f field evaluatin f equipment as these terms are used in tw r mre NEC articles, specifically in the phtvltaic articles in Chapter 6. These definitins are extracted material frm NFPA 790 (Standard fr Cmpetency f Third- Party Field Evaluatin Bdies). Receptacle. A receptacle is a cntact device installed at the utlet fr the cnnectin f an attachment plug, r fr the direct cnnectin f listed and labeled electrical utilizatin equipment designed t mate with the crrespnding cntact device. A single receptacle is a single cntact device with n ther cntact device n the same yke. A multiple receptacle is tw r mre cntact devices n the same yke. Reasn fr the Change The definitin was mdified t accmmdate electrical utilizatin equipment emplying a means, ther than a traditinal attachment plug cap, t cnnect directly t the crrespnding cntact device. ARTICLE 110: Requirements fr Electrical Installatins Examinatin, Identificatin, Installatin, and Use f Equipment (A)Examinatin. In judging equipment, cnsideratins such as the fllwing shall be evaluated: (1) Suitability fr installatin and use in cnfrmity with the prvisins f this Cde Infrmatinal Nte N. 1: Equipment may be new, recnditined, refurbished, r remanufactured. Reasn fr the Change A new infrmatinal nte has been added at 110.3(A)(1) indicating that electrical equipment culd be either new, recnditined, refurbished r remanufactured when installed and inspected and examined Examinatin, Identificatin, Installatin, and Use, and Listing (Prduct Certificatin) f Equipment (C) Listing. Prduct testing, evaluatin, and listing (prduct certificatin) shall be perfrmed by recgnized qualified electrical testing labratries and shall be in accrdance with applicable prduct standards recgnized as achieving equivalent and effective safety fr equipment installed t cmply with this Cde NEC Significant Cde Changes Part 1 3

6 Infrmatinal Nte: The Occupatinal Safety and Health Administratin (OSHA) recgnizes qualified electrical testing labratries that perfrm evaluatins, testing, and certificatin f certain prducts t ensure that they meet the requirements f bth the cnstructin and general industry OSHA electrical standards. If the listing (prduct certificatin) is dne under a qualified electrical testing labratry prgram, this listing mark signifies that the tested and certified prduct cmplies with the requirements f ne r mre apprpriate prduct safety test standards. Reasn fr the Change A new List Item (C) was added at requiring the listing prcess be executed by a qualified third-party electrical testing labratry and that the prduct testing and certificatin prcess be in accrdance with apprpriate prduct standards Electrical Cnnectins (D) Installatin. Where a tightening trque is indicated as a numeric value n equipment r in installatin instructins prvided by the manufacturer, a calibrated trque tl shall be used t achieve the indicated trque value, unless the equipment manufacturer has prvided installatin instructins fr an alternative methd f achieving the required trque. Reasn fr the Change The Infrmatinal Nte that was lcated after the parent text f has been deleted and replaced with enfrceable Cde text at new (D). This new requirement calls fr the implementatin f tightening trque tls where trqueing is specified n the equipment r in installatin instructins prvided by the manufacturer Arc-Flash Hazard Warning (B)Service Equipment. In ther than dwelling units, in additin t the requirements in (A), a permanent label shall be field r factry applied t service equipment rated 1200 amps r mre. The label shall meet the requirements f (B) and cntain the fllwing infrmatin: (1) Nminal system vltage (2) Available fault current at the service vercurrent prtective devices (3) The clearing time f service vercurrent prtective devices based n the available fault current at the service equipment (4) The date the label was applied Exceptin: Service equipment labeling shall nt be required if an arc flash label is applied in accrdance with acceptable industry practice. Infrmatinal Nte N. 1: NFPA 70E , Standard fr Electrical Safety in the Wrkplace, prvides guidance, such as determining the severity f ptential expsure, planning safe wrk practices, arc flash labeling, and selecting persnal prtective equipment. Infrmatinal Nte N. 2: ANSI Z , Prduct Safety Signs and Labels, prvides guidelines fr the design f safety signs and labels fr applicatin t prducts. Infrmatinal Nte N. 3: Acceptable industry practices fr equipment labeling are described in NFPA 70E-2015 Standard fr Electrical Safety in the Wrkplace. This standard prvides specific criteria fr develping arcflash labels fr equipment that prvides nminal system vltage, incident energy levels, arc-flash bundaries, minimum required levels f persnal prtective equipment, and s frth. Reasn fr the Change A new List Item (B) was added requiring nn-dwelling unit service equipment rated 1200 amperes r mre t be labeled with the nrmal system vltage, available fault current, clearing times, and date the label was applied Marking. (A) Manufacturer s Equipment Markings. (2) Recnditined Equipment. Recnditined equipment shall be marked with the name, trademark, r ther descriptive marking by which the rganizatin respnsible fr recnditining the electrical equipment can be identified, alng with the date f the 2017 NEC Significant Cde Changes Part 1 4

7 recnditining. Recnditined equipment shall be identified as recnditined and apprval f the recnditined equipment shall nt be based slely n the equipment s riginal listing. Exceptin: In industrial ccupancies, where cnditins f maintenance and supervisin ensure that nly qualified persns service the equipment, the markings indicated in (A)(2) shall nt be required. Infrmatinal Nte: Industry standards are available fr applicatin f recnditined and refurbished equipment. Nrmal servicing f equipment that remains within a facility shuld nt be cnsidered recnditining r refurbishing. Reasn fr the Change New requirements were added at (A)(2) t require refurbished, recnditined, r remanufactured equipment t be marked with the name, trademark, r ther descriptive marking by which the rganizatin respnsible fr recnditining the electrical equipment can be identified. The date f the recnditining must als be established n the nameplate r marking Spaces Abut Electrical Equipment (A) Wrking Space. Wrking space fr equipment perating at vlts, nminal, r less t grund and likely t require examinatin, adjustment, servicing, r maintenance while energized shall cmply with the dimensins f (A) (1), (A)(2), and (A)(3), and (A)(4) r as required r permitted elsewhere in this Cde. Infrmatinal Nte: NFPA 70E-2015, Standard fr Electrical Safety in the Wrkplace, prvides guidance, such as determining severity f ptential expsure, planning safe wrk practices, arc flash labeling, and selecting persnal prtective equipment. (4) Limited Access. Where equipment perating at 1000 vlts, nminal, r less t grund and likely t require examinatin, adjustment, servicing, r maintenance while energized is required by installatin instructins r functin t be lcated in a space with limited access, all f the fllwing shall apply: (a)where equipment is installed abve a lay-in ceiling, there shall be an pening nt smaller than 559 mm 559 mm (22 in. 22 in.), r in a crawl space, there shall be an accessible pening nt smaller than 559 mm 762 mm (22 in. 30 in.). (b)the width f the wrking space shall be the width f the equipment enclsure r a minimum f 762 mm (30 in.), whichever is greater. (c)all enclsure drs r hinged panels shall be capable f pening a minimum f 90 degrees. (d)the space in frnt f the enclsure shall cmply with the depth requirements f Table (A)(1). The maximum height f the wrking space shall be the height necessary t install the equipment in the limited space. A hrizntal ceiling structural member r access panel shall be permitted in this space. Reasn fr the Change The same basic limited access wrking space requirements at (B) were relcated t (A)(4) t braden this requirement t mre than just duct heaters. Prvisins fr limited access t crawl spaces were added t this requirement as well Inspectins and Tests (A) Pre-energizatin and Operating Tests. Where required elsewhere in this Cde, the cmplete electrical system design, including settings fr prtective, switching, and cntrl circuits, shall be prepared in advance and made available n request t the authrity having jurisdictin and shall be tested when first installed n-site. (B) Test Reprt. A test reprt cvering the results f the tests required in (A) shall be available t the authrity having jurisdictin prir t energizatin and made available t thse authrized t install, perate, test, and maintain the system. Reasn fr the Change New requirements were added at fr pre-energizatin testing and reprting f 2017 NEC Significant Cde Changes Part 1 5

8 electrical equipment (ver 1000 vlts) upn request by the AHJ. Since it is lcated in Article 110, this will apply t all equipment rated ver 1000 vlts regardless f its lcatin. CHAPTER 2 ARTICLE 210 Branch Circuits 210.5(C)(1), Exceptin Identificatin fr Branch Circuits (C)Identificatin f Ungrunded Cnductrs. Ungrunded cnductrs shall be identified in accrdance with 210.5(C)(1) r (2), as applicable. (1)Branch Circuits Supplied frm Mre Than One Nminal Vltage System. Where the premises wiring system has branch circuits supplied frm mre than ne nminal vltage system, each ungrunded cnductr f a branch circuit shall be identified by phase r line and system at all terminatin, cnnectin, and splice pints in cmpliance with 210.5(C)(1)(a) and (b). (a)means f Identificatin. The means f identificatin shall be permitted t be by separate clr cding, marking tape, tagging, r ther apprved means. (b)psting f Identificatin Means. The methd utilized fr cnductrs riginating within each branch-circuit panelbard r similar branch-circuit distributin equipment shall be dcumented in a manner that is readily available r shall be permanently psted at each branch-circuit panelbard r similar branchcircuit distributin equipment. The label shall be f sufficient durability t withstand the envirnment invlved and shall nt be handwritten. Exceptin: In existing installatins where a vltage system(s) already exists and a different vltage system is being added, it shall be permissible t mark nly the new system vltage. Existing unidentified systems shall nt be required t be identified at each terminatin, cnnectin, and splice pint in cmpliance with 210.5(C)(1)(a) and (b). Labeling shall be required at each vltage system distributin equipment t identify that nly ne vltage system has been marked fr a new system(s). The new system label(s) shall include the wrds ther unidentified systems exist n the premises. Reasn fr the Change The previus identificatin requirements fr branch circuits supplied frm mre than ne nminal vltage system mved frward fr the 2017 NEC with a new exceptin added fr relief frm identifying each ungrunded cnductr fr existing installatins where a vltage system(s) already exists and a different vltage system is being added. A new requirement was als added cncerning the durability and makeup f the labels Grund-Fault Circuit- Interrupter Prtectin fr Persnnel. Grund-fault circuit-interrupter prtectin fr persnnel shall be prvided as required in 210.8(A) thrugh (D) (E). The grund-fault circuit interrupter shall be installed in a readily accessible lcatin. Infrmatinal Nte N. 1: See fr grund-fault circuit-interrupter prtectin fr persnnel Infrmatinal Nte N. 2: See 422.5(A) fr GFCI requirements fr appliances. Fr the purpses f this sectin, when determining distance frm receptacles the distance shall be measured as the shrtest path the crd f an appliance cnnected t the receptacle wuld fllw withut piercing a flr, wall, ceiling, r fixed barrier, r passing thrugh a dr, drway, r windw. Reasn fr the Change A new prvisin was added t the parent text f t indicate that measurements frm receptacles t bjects (such as a sink) that wuld qualify fr GFCI prtectin shuld be measured as the shrtest path a crd f an appliance cnnected t a receptacle wuld take withut piercing a flr, wall, ceiling, r fixed barrier, r passing thrugh a dr, drway, r windw NEC Significant Cde Changes Part 1 6

9 210.8(A)(7) Grund-Fault Circuit- Interrupter Prtectin fr Persnnel (A)Dwelling Units. All 125-vlt, singlephase, 15- and 20-ampere receptacles installed in the lcatins specified in 210.8(A)(1) thrugh (10) shall have grund-fault circuit-interrupter prtectin fr persnnel. (7) Sinks where receptacles are installed within 1.8 m (6 ft) f frm the utside tp inside edge f the sink bwl Reasn fr the Change All 125-vlt, single-phase, 15- and 20-ampere receptacles installed within 1.8 m (6 ft) f the tp inside edge f the bwl f any dwelling unit sink (including the kitchen sink) requires GFCI prtectin withut the measurement piercing a flr, wall, ceiling, r fixed barrier, r passing thrugh a dr, drway, r windw (B) Grund-Fault Circuit- Interrupter Prtectin fr Persnnel (B) Other Than Dwelling Units. All 125- vlt, single-phase, 15-and 20-ampere receptacles rated 150 vlts t grund r less, 50 amperes r less; and three-phase receptacles rated 150 vlts t grund r less, 100 amperes r less, installed in the lcatins specified in 210.8(B)(1) thrugh (8) (10) shall have grund-fault circuitinterrupter prtectin fr persnnel. Reasn fr the Change The GFCI requirements at Other Than Dwelling Units still include cverage f 125-vlt, single-phase, 15- and 20-ampere receptacles. These requirements have been expanded t include all single-phase receptacles rated 150 vlts t grund r less, 50 amperes r less; and three-phase receptacles rated 150 vlts t grund r less, 100 amperes r less (B)(9) Grund-Fault Circuit- Interrupter Prtectin fr Persnnel. (9) Crawl spaces at r belw grade level Reasn fr the Change GFCI prtectin is nw required fr all single-phase receptacles rated 150 vlts t grund r less, 50 amperes r less; and threephase receptacles rated 150 vlts t grund r less, 100 amperes r less installed in nndwelling unit crawl spaces (B)(10) Grund-Fault Circuit- Interrupter Prtectin fr Persnnel. (10) Unfinished prtins r areas f the basement nt intended as habitable rms Reasn fr the Change GFCI prtectin fr receptacles installed in unfinished basements has been expanded t include cmmercial applicatins as well as dwelling units. Revisins t the parent text at 210.8(B) has expanded the receptacles invlved t thse that are rated 150 vlts t grund r less, 50 amperes r less; and threephase receptacles rated 150 vlts t grund r less, 100 amperes r less (E) Grund-Fault Circuit- Interrupter Prtectin fr Persnnel (E) Crawl Space Lighting Outlets. GFCI prtectin shall be prvided fr lighting utlets nt exceeding 120 vlts installed in crawl spaces. Reasn fr the Change In additin t the GFCI requirements fr lighting utlets f the previus Cde, GFCI prtectin is nw required fr lighting utlets nt exceeding 120 vlts in crawl spaces where space is at r belw grade level (C)(4) Garage Branch Circuits (4) Garage Branch Circuits. In additin t the number f branch circuits required by ther parts f this sectin, at least ne 120-vlt, 20- ampere branch circuit shall be installed t supply receptacle utlets in attached garages and in detached garages with electric pwer. This circuit shall have n ther utlets. Exceptin: This circuit shall be permitted t supply readily accessible utdr receptacle utlets NEC Significant Cde Changes Part 1 7

10 Reasn fr the Change The branch circuit supplying receptacle utlets in dwelling unit garages is nw required t be a 120-vlt, 20-ampere rated branch circuit. The garage receptacle utlet branch circuit is still prhibited frm serving ther utlets with the exceptin f readily accessible receptacles lcated utdrs (C) Arc-Fault Circuit- Interrupter Prtectin (C) Guest Rms and Guest Suites. All 120-vlt, single-phase, 15-and 20-ampere branch circuits supplying utlets and devices installed in guest rms and guest suites f htels and mtels shall be prtected by any f the means described in (A)(1) thrugh (6). Reasn fr the Change New prvisins were added at (C) requiring AFCI prtectin fr all 120-vlt, single-phase, 15- and 20-ampere branch circuits supplying utlets and devices installed in guest rms and guest suites f htels and mtels, regardless f the existence f permanent prvisins fr cking r nt Electric Vehicle Branch Circuit Cde Language: Electric Vehicle Branch Circuit. An utlet(s) installed fr the purpse f charging electric vehicles shall be supplied by a separate branch circuit. This circuit shall have n ther utlets. Infrmatinal Nte: See fr the definitin f Electric Vehicle Electric Vehicle Branch Circuit. An utlet(s) Each utlet installed fr the purpse f charging electric vehicles shall be supplied by a separate an individual branch circuit. This Each circuit shall have n ther utlets. Reasn fr the Change The requirement fr a separate branch circuit fr electric vehicle utlets was relcated t , the article fr electric vehicle charging systems. During this relcatin, the requirement fr a separate branch circuit was changed t an individual branch circuit. There is still n requirement fr an utlet t be installed specifically fr the purpse f charging f an electric vehicle (A)(2)(1) Dwelling Unit Receptacle Outlets (2)Wall Space. As used in this sectin, a wall space shall include the fllwing: (1)Any space 600 mm (2 ft) r mre in width (including space measured arund crners) and unbrken alng the flr line by drways and similar penings, fireplaces, and fixed cabinets that d nt have cuntertps r similar wrk surfaces Reasn fr the Change Only fixed cabinets that d nt have cuntertps r similar wrk surfaces are nw cnsidered as an item (alng with drways and fireplaces) that wuld nt be cunted as wall space cncerning receptacle spacing and lcatin requirements Dwelling Unit Receptacle Outlets (B) Small Appliances (1) Receptacle Outlets Served. In the kitchen, pantry, breakfast rm, dining rm, r similar area f a dwelling unit, the tw r mre 20-ampere small-appliance branch circuits required by (C)(1) shall serve all wall and flr receptacle utlets cvered by (A), all cuntertp utlets cvered by (C), and receptacle utlets fr refrigeratin equipment. Exceptin N. 1: In additin t the required receptacles specified by , switched receptacles supplied frm a general-purpse branch circuit as defined in (A)(1), Exceptin N. 1, shall be permitted. Exceptin N. 2: The receptacle utlet fr refrigeratin equipment In additin t the required receptacles specified by , a receptacle utlet t serve a specific appliance shall be permitted t be supplied frm an individual branch circuit rated 15 amperes r greater NEC Significant Cde Changes Part 1 8

11 Reasn fr the Change Any specific dwelling unit kitchen appliance is permitted by exceptin t be supplied frm an individual branch circuit rated 15 amperes r greater rather than frm ne f the 20- ampere rated small-appliance branch circuits (C)(3) Dwelling Unit Receptacle Outlets (C) Cuntertps and Wrk Surfaces. In kitchens, pantries, breakfast rms, dining rms, and similar areas f dwelling units, receptacle utlets fr cuntertp and wrk surface spaces shall be installed in accrdance with (C)(1) thrugh (C)(5). (3) Peninsular Cuntertp Spaces. At least ne receptacle utlet shall be installed at each peninsular cuntertp lng dimensin space with a lng dimensin f 600 mm (24 in.) r greater and a shrt dimensin f 300 mm (12 in.) r greater. A peninsular cuntertp is measured frm the cnnecting edge cnnected perpendicular wall. Reasn fr the Change At least ne receptacle utlet is still required at each peninsular cuntertp with a lng dimensin f 600 mm (24 in.) r greater and a shrt dimensin f 300 mm (12 in.) r greater, but the measurement is nw measured frm the cnnected perpendicular wall (G) Dwelling Unit Receptacle Outlets (G) Basements, Garages, and Accessry Buildings. Fr a ne- and twfamily dwellings, at least ne receptacle utlet shall be installed in the areas specified in (G)(1) thrugh (3). These receptacles shall be in additin t receptacles required fr specific equipment. Reasn fr the Change The same ne receptacle utlet requirement still applies t qualifying basements, garages, and accessry buildings, but this requirement has been extended t tw-family dwellings as well as ne-family dwellings (G)(1) Dwelling Unit Receptacle Outlets (G) Basements, Garages, and Accessry Buildings. Fr a ne- and twfamily dwellings, at least ne receptacle utlet shall be installed in the areas specified in (G)(1) thrugh (3). These receptacles shall be in additin t receptacles required fr specific equipment. (1) Garages. In each attached garage and in each detached garage with electric pwer,. The branch circuit supplying this receptacle(s) shall nt supply utlets utside f the garage. At at least ne receptacle utlet shall be installed fr in each car space vehicle bay and nt mre than 1.7 m (51/2 ft) abve the flr. Reasn fr the Change In each attached garage and in each detached garage with electric pwer, at least ne receptacle utlet is required t be installed in each vehicle bay and nt mre than 1.7 m (51/2 ft) abve the flr. The branch circuit supplying these receptacle(s) cannt serve utlets utside f the garage with the exceptin f readily accessible receptacles lcated utdrs. This latter requirement cncerning the branch circuit supplying the garage is nw lcated at (C)(4) Electrical Service Areas At least ne 125-vlt, single-phase, 15- r 20- ampere-rated receptacle utlet shall be installed in an accessible lcatin within 15 m (50 ft) 7.5 m (25 ft) f the indr electrical service equipment. The required receptacle utlet shall be lcated within the same rm r area as the service equipment. Exceptin N. 1: The receptacle utlet shall nt be required t be installed in ne-and-tw-family dwellings. Exceptin N. 2: Where the service vltage is greater than 120 vlts t grund, a receptacle utlet shall nt be required fr services dedicated t equipment cvered in Articles 675 and NEC Significant Cde Changes Part 1 9

12 Reasn fr the Change At least ne 125-vlt, single-phase, 15- r 20- ampere-rated receptacle utlet is still required t be installed at the electrical service equipment. The maximum distance this receptacle utlet can be lcated frm the electrical service has been shrtened t 7.5 m (25 ft) and limited t indr service equipment nly. This required receptacle utlet is nw required t be installed in an accessible lcatin and must be lcated within the same rm r area as the service equipment. This requirement is still nt applicable t ne- and tw-family dwellings. A new exceptin was als added allwing services dedicated t equipment cvered in Articles 675 and 682 t be exempt frm this requirement when the service vltage is greater than 120 vlts t grund (C) Lighting Outlets Required (C) Other Than Dwelling Units All Occupancies. Fr attics and underflr spaces, cntaining equipment requiring servicing, such as heating, air-cnditining, and refrigeratin equipment utility rms, and basements, at least ne lighting utlet cntaining a switch r cntrlled by a wall switch shall be installed in such where these spaces are used fr strage r cntain equipment requiring servicing. At least ne pint f cntrl shall be at the usual pint f entry t these spaces. The lighting utlet shall be prvided at r near the equipment requiring servicing. Reasn fr the Change The title f (C) was changed frm Other Than Dwelling Units t All Occupancies and the text at this prvisin was revised t mirrr the Cde text at (A)(3) fr dwelling units. This lighting utlet requirement fr strage r equipment spaces nw applies t dwelling units as well as nn-dwelling unit attics, underflr spaces, utility rms, and basements Meeting Rms Meeting Rms. (A) General. Each meeting rm f nt mre than 93 m 2 (1000 ft 2 ) in ther than dwelling units shall have utlets fr nnlcking-type, 125-vlt, 15- r 20-ampere receptacles. The utlets shall be installed in accrdance with (B). Where a rm r space is prvided with mvable partitin(s), each rm size shall be determined with the partitin in the psitin that results in the smallest size meeting rm. Infrmatinal Nte N. 1: Fr the purpses f this sectin, meeting rms are typically designed r intended fr the gathering f seated ccupants fr such purpses as cnferences, deliberatins, r similar purpses, where prtable electrnic equipment such as cmputers, prjectrs, r similar equipment is likely t be used. Infrmatinal Nte N. 2: Examples f rms that are nt meeting rms include auditriums, schlrms, and cffee shps. (B) Receptacle Outlets Required. The ttal number f receptacle utlets, including flr utlets and receptacle utlets in fixed furniture, shall nt be less than as determined in (1) and (2). These receptacle utlets shall be permitted t be lcated as determined by the designer r building wner. (1) Receptacle Outlets in Fixed Walls. Receptacle utlets shall be installed in accrdance with (A)(1) thrugh (A)(4). (2) Flr Receptacle Outlets. A meeting rm that is at least 3.7 m (12 ft) wide and that has a flr area f at least 20 m 2 (215 ft 2 ) shall have at least ne receptacle utlet lcated in the flr at a distance nt less than 1.8 m (6 ft) frm any fixed wall fr each 20 m2 (215 ft 2 ) r majr prtin f flr space. Infrmatinal Nte N. 1: See Sectin (B) fr flr bxes used fr receptacles lcated in the flr. Infrmatinal Nte N. 2: See Article 518 fr assembly ccupancies designed fr 100 r mre persns. Reasn fr the Change New prvisins were added at with minimum prvisins fr receptacle utlets 2017 NEC Significant Cde Changes Part 1 10

13 placement and wall spacing requirements in nn-dwelling unit meeting rms such as thse fund at htels and cnventin centers. See NEC text fr cmplete requirements and specifics. ARTICLE 215 Feeders Minimum Rating and Size Cde Language: Minimum Rating and Size. (A) Feeders Nt Mre Than 600 Vlts. (1) General. Feeder cnductrs shall have an ampacity nt less than required t supply the lad as calculated in Parts III, IV, and V f Article 220. Cnductrs shall be sized t carry nt less than the larger f 215.2(A)(1)(a) r (b). (a)where a feeder supplies cntinuus lads r any cmbinatin f cntinuus and nncntinuus lads, the minimum feeder cnductr size shall have an allwable ampacity nt less than the nncntinuus lad plus 125 percent f the cntinuus lad. Exceptin N. 1: If the assembly, including the vercurrent devices prtecting the feeder(s), is listed fr peratin at 100 percent f its rating, the allwable ampacity f the feeder cnductrs shall be permitted t be nt less than the sum f the cntinuus lad plus the nncntinuus lad. Exceptin N. 2: Where a prtin f a feeder is cnnected at bth its supply and lad ends t separately installed pressure cnnectins as cvered in (C)(2), it shall be permitted t have an allwable ampacity nt less than the sum f the cntinuus lad plus the nncntinuus lad. N prtin f a feeder installed under the prvisins f this exceptin shall extend int an enclsure cntaining either the feeder supply r the feeder lad terminatins, as cvered in (C)(1). Exceptin N. 3: Grunded cnductrs that are nt cnnected t an vercurrent device shall be permitted t be sized at 100 percent f the cntinuus and nncntinuus lad. (b)the minimum feeder cnductr size shall have an allwable ampacity nt less than the maximum lad t be served after the applicatin f any adjustment r crrectin factrs. [(3) Infrmatinal Ntes unchanged] Exceptin N. 1: If the assembly, including the vercurrent devices prtecting the feeder(s), is listed fr peratin at 100 percent f its rating, the allwable ampacity f the feeder cnductrs shall be permitted t be nt less than the sum f the cntinuus lad plus the nncntinuus lad. Exceptin N. 2: Grunded cnductrs that are nt cnnected t an vercurrent device shall be permitted t be sized at 100 percent f the cntinuus and nncntinuus lad. Reasn fr the Change The previus exceptins t 215.2(A)(1)(b) have been relcated after 215.2(A)(1)(a). This relcatin clarifies that these exceptins apply t the main rule that the feeder cnductrs must have an allwable ampacity f nt less than the nncntinuus lad plus 125 percent f the cntinuus lad. A new exceptin was als added that allws a prtin f a feeder that is cnnected at bth its supply and lad ends t separately installed pressure cnnectins t have an allwable ampacity nt less than the sum f the cntinuus lad plus the nncntinuus lad (rather than the nncntinuus lad plus 125 percent f the cntinuus lad). ARTICLE 220 Article 220 and Branch- Circuit, Feeder, and Service Lad Calculatins Article 220 Branch-Circuit, Feeder, and Service Lad Calculatins Scpe. This article prvides requirements fr calculating branch-circuit, feeder, and service lads. Part I prvides fr general requirements fr calculatin methds. Part II prvides calculatin methds fr branch-circuit lads. Parts III and IV prvide calculatin methds fr feeders feeder and services service 2017 NEC Significant Cde Changes Part 1 11

14 lads. Part V prvides calculatin methds fr farms farm lads. Reasn fr the Change The title f Article 220 was changed t Branch Circuit, Feeder, and Service Lad Calculatins. Parts f the scpe f the article were changed t clarify that Parts III and IV prvide calculatin methds fr feeder and service lads. Text cncerning Part V was revised t clarify that this part f the article cvers calculatin methds fr farm lads. ARTICLE 225 Outside Branch Feeders and Circuits (F) Number f Supplies. (Outside Branch Circuits and Feeders) Cde Language: Number f Supplies. (Outside Branch Circuits and Feeders) A building r ther structure that is served by a branch circuit r feeder n the lad side f a service discnnecting means shall be supplied by nly ne feeder r branch circuit unless permitted in (A) thrugh (E) (F). Fr the purpse f this sectin, a multiwire branch circuit shall be cnsidered a single circuit. Where a branch circuit r feeder riginates in these additinal buildings r ther structures, nly ne feeder r branch circuit shall be permitted t supply pwer back t the riginal building r structure, unless permitted in (A) thrugh (E)(F). (F) One- r Tw-Family Dwelling Unit(s). Fr a ne- r tw- family dwelling unit(s) with multiple feeders, it shall be permissible t install nt mre than six discnnects gruped at ne lcatin where the feeders enter the building, prvided the feeder cnductrs riginate at the same switchbard, panelbard, r vercurrent Reasn fr the Change A new first level subdivisin (F) was added t that will allw multiple feeders at ne- r tw-family dwelling unit(s) with nt mre than six gruped discnnecting means. These feeder cnductr(s) are t riginate at the same switchbard, panelbard, r vercurrent prtective device lcatin. ARTICLE 230 Services (B)(5) Clearances (B) Vertical Clearance fr Overhead Service Cnductrs. Overhead service cnductrs, where nt in excess f 600 vlts, nminal, shall have the fllwing m (5)7.5 m (24.5 ft) ver tracks f railrads Reasn fr the Change A new vertical clearance f 7.5 m (24.5 ft) was added at (B)(5) fr verhead service cnductrs installed ver the tracks f a railrad. This will crdinate with the same requirement fr utside verhead branch circuits and feeders in Article Branch-Circuit Receptacle Requirements Supprts ver Buildings. Service cnductrs passing ver a rf shall be securely supprted by substantial structures. Fr a grunded system, where the substantial structure is metal, it shall be bnded by means f a bnding jumper and listed cnnectr t the grunded verhead service cnductr. The bnding jumper shall be f the same cnductr size and material as the grunded verhead service cnductr, and in n case smaller than mandated in (C)(1) based n the size f the ungrunded service cnductrs. Where practicable, such supprts shall be independent f the building. Reasn fr the Change Metal supprt structures that supprt verhead service cnductrs installed ver a rf are nw required t be bnded t the grunded verhead service cnductr. ARTICLE 240 Overcurrent Prtectin 2017 NEC Significant Cde Changes Part 1 12

15 Table 240.6(A) Standard Ampere Ratings Standard Ampere Ratings. (A) Fuses and Fixed-Trip Circuit Breakers. The standard ampere ratings fr fuses and inverse time circuit breakers shall be cnsidered 15, 20, 25, 30, 35, 40, 45, 50, 60, 70, 80, 90, 100, 110, 125, 150, 175, 200, 225, 250, 300, 350, 400, 450, 500, 600, 700, 800, 1000, 1200, 1600, 2000, 2500, 3000, 4000, 5000, and 6000 amperes as shwn in Table 240.6(A). Additinal standard ampere ratings fr fuses shall be 1, 3, 6, 10, and 601. The use f fuses and inverse time circuit breakers with nnstandard ampere ratings shall be permitted. Reasn fr the Change The standard ampere ratings fr fuses and inverse time circuit breakers have been revised t be included in a list frmat lcated at new Table 240.6(A) shwn belw. Table 240.6(A) Arc Energy Reductin Arc Energy Reductin. Where fuses rated 1200 amperes r higher are installed, (A) and (B) shall apply. This requirement shall becme effective January 1, (A) Dcumentatin. Dcumentatin shall be available t thse authrized t design, install, perate, r inspect the installatin as t the lcatin f the fuses. (B) Methd t Reduce Clearing Time. A fuse shall have a clearing time f 0.07 secnds r less at the available arcing current, r ne f the fllwing shall be prvided: (1) Differential relaying (2) Energy-reducing maintenance switching with lcal status indicatr (3) Energy-reducing active arc flash mitigatin system (4) An apprved equivalent means Infrmatinal Nte N. 1: An energyreducing maintenance switch allws a wrker t set a discnnect switch t reduce the clearing time while the wrker is wrking within an arcflash bundary as defined in NFPA 70E-2015, Standard fr Electrical Safety in the Wrkplace, and then t set the discnnect switch back t a nrmal setting after the ptentially hazardus wrk is cmplete. Infrmatinal Nte N. 2: An energy-reducing active arc flash mitigatin system helps in reducing arcing duratin in the electrical distributin system. N change in the discnnect switch r the settings f ther devices is required during maintenance when a wrker is wrking within an arc flash bundary as defined in NFPA 70E- 2015, Standard fr Electrical Safety in the Wrkplace. Infrmatinal Nte N. 3: IEEE 1584, IEEE Guide fr Perfrming Arc Flash Hazard Calculatins, is ne f the available methds that prvides guidance in determining arcing current. Reasn fr the Change Cmparable methds f incident energy reductin as that f have been 2017 NEC Significant Cde Changes Part 1 13

16 intrduced int the 2017 NEC at fr fuses rated at 1200 amperes and greater. ARTICLE 250 Grunding and Bnding (6) Circuits Nt t Be Grunded Circuits Nt t Be Grunded. The fllwing circuits shall nt be grunded: (6) Class 2 lad-side circuits fr suspended ceiling lw-vltage pwer grid distributin systems as prvided in (B). Reasn fr the Change A new List Item (6) was added t fr circuits nt t be grunded with the additin f Class 2 lad-side circuits fr suspended ceiling lw-vltage pwer grid distributin systems as prvided in (B) (A)(4) and (A)(5) Grunding Separately Derived Alternating- Current Systems (4) Grunding Electrde. The building r structure grunding electrde system shall be used as the grunding electrde fr the separately derived system. If lcated utdrs, the grunding electrde shall be in accrdance with (C). as near as practicable t, and preferably in the same area as, the grunding electrde cnductr cnnectin t the system. The grunding electrde shall be the nearest f ne f the fllwing: (1) Metal water pipe grunding electrde as specified in (A)(1) (2) Structural metal grunding electrde as specified in (A)(2) Exceptin N. 1: Any f the ther electrdes identified in (A) shall be used if the electrdes specified by (A)(4) are nt available. Exceptin N. 2 t (1) and (2): If a separately derived system riginates in equipment that is listed and identified equipment as suitable fr use as service equipment, the grunding electrde used fr the service r feeder equipment shall be permitted t be used as the grunding electrde fr the separately derived system. (5) Grunding Electrde Cnductr, Single Separately Derived System. A grunding electrde cnductr fr a single separately derived system shall be sized in accrdance with fr the derived ungrunded cnductrs. It shall be used t cnnect the grunded cnductr f the derived system t the grunding electrde as specified in accrdance with (A)(4), r as permitted in (C)(1) and (2). This cnnectin shall be made at the same pint n the separately derived system where the system bnding jumper is cnnected. [See NEC text fr Exceptin N. 1, 2, and 3 t (A)(5)] Reasn fr the Change Fr the 2017 NEC, any f the building r structure grunding electrde(s) that are present can nw be used as the grunding electrde(s) fr a separately derived system. The grunding electrde(s) fr the separately derived system d nt have t be lcated near the grunding electrde cnductr cnnectin. The metal water piping and the structural metal frame as cvered in (C)(1) and (2) have been recgnized as cnductrs t extend the grunding electrde cnnectin at (A)(5) (A)(6)(a) Grunding Separately Derived Alternating- Current Systems (a)cmmn Grunding Electrde Cnductr. The cmmn grunding electrde cnductr shall be permitted t be ne f the fllwing: (1) A cnductr f the wire type nt smaller than 3/0 AWG cpper r 250 kcmil aluminum (2) A metal water pipe that cmplies with (C)(1) (3) The metal structural frame f the building r structure that cmplies with (A)(2) (C)(2) r is cnnected t the grunding 2017 NEC Significant Cde Changes Part 1 14

17 electrde system by a cnductr that shall nt be smaller than 3/0 AWG cpper r 250 kcmil aluminum Reasn fr the Change A metal water pipe that cmplies with (C)(1) was added t the allwable methds fr a cmmn grunding electrde cnductr fr multiple separately derived systems. Revisins were als made t the prvisins f a metal structural frame f a building r structure qualifying as a cmmn grunding electrde cnductr fr multiple separately derived systems (A)(2) Grunding Electrdes (2) Metal Frame f the Building r In- Grund Supprt Structure(s). The metal frame f the building r structure that is cnnected t the earth by ne r mre f the fllwing methds: (1) At least One r mre structural metal ingrund supprt structure(s) member that is in direct cntact with the earth vertically fr 3.0 m (10 ft) r mre, with r withut cncrete encasement. If multiple metal in-grund supprt structures are present at a building r a structure, it shall be permissible t bnd nly ne int the grunding electrde system. (2) Hld-dwn blts securing the structural steel clumn that are cnnected t a cncreteencased electrde that cmplies with (A)(3) and is lcated in the supprt fting r fundatin. The hld-dwn blts shall be cnnected t the cncrete-encased electrde by welding, exthermic welding, the usual steel tie wires, r ther apprved means. Infrmatinal Nte: Metal in-grund supprt structures include, but are nt limited t, pilings, casings, and ther structural metal. Reasn fr the Change The title f (A)(2) was changed frm Metal Frame f a Building t Metal In- Grund Supprt Structure. Only ne item remains that wuld qualify as a metal ingrund supprt structure grunding electrde: an in-grund supprt structure that is in direct cntact with the earth vertically fr 3.0 m (10 ft) r mre, with r withut cncrete encasement (B)(3) Grunding Electrdes (B) Nt Permitted fr Use as Grunding Electrdes. The fllwing systems and materials shall nt be used as grunding electrdes: (1) Metal undergrund gas piping systems (2) Aluminum (3) The structures and structural reinfrcing steel described in (B) (1) and (B)(2) Reasn fr the Change A third item was added t the list f bjects that are prhibited frm being used as a grunding electrde defined at (B). The structures and structural reinfrcing steel f an in-grund swimming pl as described in (B)(1) and (B)(2) are nw prhibited frm being used as a grunding electrde, as well as the tw items identified in the previus editin f the Cde (A), (B), and (C) Size f Alternating-Current Grunding Electrde Cnductr (A) Cnnectins t a Rd, Pipe, r Plate Electrde(s). Where If the grunding electrde cnductr r bnding jumper is cnnected t a single r multiple rd, pipe, r plate electrde(s), r any cmbinatin theref, as permitted described in (A)(5) r (A)(7), that prtin f the cnductr that is the sle cnnectin t the grunding electrde(s) des nt extend n t ther types f electrdes that require a larger size cnductr, the grunding electrde cnductr shall nt be required t be larger than 6 AWG cpper wire r 4 AWG aluminum wire. (B) Cnnectins t Cncrete-Encased Electrdes. Where If the grunding electrde cnductr r bnding jumper is cnnected t a single r multiple cncrete-encased electrde(s) as permitted described in (A)(3), that prtin f the cnductr that is the sle cnnectin t the grunding electrde(s) des 2017 NEC Significant Cde Changes Part 1 15

18 nt extend n t ther types f electrdes that require a larger size cnductr, the grunding electrde cnductr shall nt be required t be larger than 4 AWG cpper wire. (C) Cnnectins t Grund Rings. Where If the grunding electrde cnductr r bnding jumper is cnnected t a grund ring as permitted described in (A)(4), that prtin f the cnductr that is the sle cnnectin t the grunding electrde des nt extend n t ther types f electrdes that require a larger size cnductr, the grunding electrde cnductr shall nt be required t be larger than the cnductr used fr the grund ring. Reasn fr the Change The sizing requirements f (A), (B), and (C) are still the same as the previus editin f the Cde, but the sle cnnectin requirement in all three subsectins was replaced with language indicating that a grunding electrde cnductr that des nt extend t ther types f electrdes requiring a larger size cnductr still qualifies fr the smaller size cnductrs (instead f the size spelled ut in Table ) (A) and (B) Bnding fr Cmmunicatin Systems Bnding fr Other Cmmunicatin Systems. Cmmunicatins system bnding terminatins shall be cnnected in accrdance with (A) r (B). (A)The Intersystem Bnding Terminatin Device. An intersystem bnding terminatin (IBT) fr cnnecting intersystem bnding cnductrs required fr ther systems shall be prvided external t enclsures at the service equipment r metering equipment enclsure and at the discnnecting means fr any additinal buildings r structures. The intersystem bnding terminatin If an IBT is used, it shall cmply with the fllwing: (Remainder f (A) unchanged. See NEC fr cmplete text.) (B)Other Means. Cnnectins t an aluminum r cpper busbar nt less than 6 mm thick 50 mm wide (1/4 in. thick 2 in. wide) and f sufficient length t accmmdate at least three terminatins fr cmmunicatin systems in additin t ther cnnectins. The busbar shall be securely fastened and shall be installed in an accessible lcatin. Cnnectins shall be made by a listed cnnectr. If aluminum busbars are used, the installatin shall als cmply with (A). Exceptin t (A) and (B): Means fr cnnecting intersystem bnding cnductrs are nt required where cmmunicatins systems are nt likely t be used. Infrmatinal Nte: The use f an IBT can reduce electrical nise n cmmunicatin systems. Reasn fr the Change The title f the sectin was changed t Bnding fr Cmmunicatin Systems. The existing text fr the intersystem bnding terminatin was placed under List Item (A) and titled, The Intersystem Bnding Terminatin Device. The six cnditins that must be met t qualify as an intersystem bnding terminatin have nt changed, and the ne exceptin fr existing buildings r structures remains the same. A new (B) was added titled, Other Means, which permits intersystem bnding cnnectins t an aluminum r cpper busbar that will accmmdate at least three terminatins fr cmmunicatin systems as well as ther cnnectins. A new exceptin was added fr (A) and (B) ffering relief frm an intersystem bnding cnnectin means where cmmunicatins systems are nt likely t be used Grunded Cnductrs, Bnding Cnductrs, and Jumpers Grunded Cnductrs, Bnding Cnductrs, and Jumpers. (A)Material. Bnding jumpers shall be f cpper, aluminum, cpper-clad aluminum, r ther crrsin-resistant material. A bnding 2017 NEC Significant Cde Changes Part 1 16