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2002 National Electrical Code
Changes
Developed and Presented by:The Codes and Standards Group of
Schneider Electric
Where We Started
2
Development Timeline
Proposal DeadlineNovember 5, 1999
Code-MakingPanels Meet
Jan 10-22, 2000
Written Ballots DueFeb 17 (or 24),
2000
Technical CorrelatingCommittee Meeting
May 8-12, 2000
NEC Report on Comments Available
July 14, 2000
Public Comment
Development Timeline
Public CommentsDue to NFPA
October 27, 2000
Code-MakingPanels meet
Dec 4-16, 2000
Written Ballots Due
Jan 5 (or 12), 2001
Technical CorrelatingCommittee Meeting
Feb 25 - Mar 1
NEC Report onComments Available
April 16, 2001
NFPA AnnualMeeting
May 13-17, 2001
Standards Council hears
Appeals on July 11, 2001
2002 NEC Issued with
Effective date of August 2, 2001
3
Use of the 2002 NEC
l 2002 is the Latest Edition of NFPA 70l Most jurisdictions specify what edition of
the NEC they followl Adoption process must recognize the 2002
edition in order for it to be the “active” document in the locality
l Some jurisdictions have already completed process to utilize the 2002 edition on January 1, 2002n e.g. North Carolina, Massachusetts
l Other jurisdictions may not adopt the 2002 edition until some future date
Numbering FormatFrom Dash to Dot
4
Acronyms
l 2002 NEC will use standard acronymsl Examples
n RMC – Rigid Metal Conduitn RNMC – Rigid Nonmetallic Conduitn EMT – Electrical Metallic Tubingn LFMC – Liquidtight Flexible Metal Conduitn ENT – Electrical Nonmetallic Tubing
n IMC – Intermediate Metal Conduitn NUCC – Nonmetallic Underground Conduit with Conductorsn AC – Armored Cablen NM – Nonmetallic sheathed cable
Article 80 (New)
l Provides a set of model administrative rules to apply and enforce the NEC
l Coversn Inspectionn Investigation of electrical firesn Review of construction plans, drawings and
specificationsn Design, alteration, modification, construction,
maintenance and testing
n Regulation and control of special events
l Article 80 is informative only (not part of the Code) unless specifically adopted by the jurisdiction
Administration and Enforcement
5
90.1(D) - Purpose
l NEC addresses fundamental principles of protection for safety contained in IEC 60364-1, Section 131
l Protection against:n Electrical shockn Thermal effectsn Overcurrent
n Fault-currentsn Overvoltage
Relation to International Standards
90.2(B)(5) – ScopeNot Covered
Service drops or laterals and associated metering
Located in legally established easements, rights of way, etc and recognized by regulatory agencies
Under exclusive control of a utility:
On property owned or leased by the utility for purpose of communications, metering, generation, control, transformation, transmission, or distribution of electric energy.
6
90.3
Chapter 1 - General
Chapter 2 - Wiring and Protection
Chapter 3 - Wiring Methods and Materials
Chapter 4 - Equipment for General Use
Chapter 5 - Special Occupancies
Chapter 6 - Special Equipment
Chapter 7 - Special Conditions
Chapter 8 - Communications Systems
Chapter 9 - Tables
Annex A through Annex D
Applies generally to all electrical installations
Supplements or modifies Chapters 1 through 4
Information only not mandatory
Applicable as referenced
Chapter 8 is not subject to the requirements of Chapters 1 through 7 except as specifically referenced in Chapter 8
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Code Arrangement
90.4
l The authority having jurisdiction can waive specific requirements or permit alternative methods
l Only allowed where “equivalent safety” is assured
l Now requires “special permission”n Special permission as defined in Article
100 requires written consent of the authority having jurisdiction
Enforcement
7
90.7Examination of Equipment for Safety
Definition of “Listed” in Article 100 states that products must meet appropriate designated standards.
90.7 states that examination of equipment for safety under standard conditions provide a basis for approval.
What are the “appropriate” designated standards?
90.7 FPN No. 3 notes that Annex A contains and informative product standards list
Annex A – Product Safety Standards
• Informative only
• List of standards used for product listing
• Makes the connection between the Code rules and properly evaluated products
90.9 – Units of Measurement
l NEC now has metric as the first dimension listedl The conversions are not exact
n e.g. 1m (3 ft)
l The installation can be made to either the SI (metric) or the “inch-pound” units
l Wire sizes did not change – still AWG and kcmil
Compliance
8
Article 100 – Definitions
l The organization, office, or, individual responsible for approving equipment, materials, an installation, or a procedure.
l This term is standardized through out the NFPA system
l Examples includen Public safety – electrical inspector, fire marshal,
fire chief, building official, others having statutory authority
n Insurance purposes – insurance inspection department, rating bureau
n Others – property owner or designeen Government – commanding officer,
departmental official
Authority Having Jurisdiction
Article 100 - DefinitionsGround-Fault Circuit Interrupter
Definition now makes it clear that a device intended to provide protection of personnel must be a Class A device.
9
Article 100 - DefinitionsLuminaire
A complete lighting unit consisting of a lamp or lamps together with the parts designed to distribute the light, to position and protect the lamps and ballast (where applicable), and to connect the lamps to the power supply.
Fixture
Lighting fixtureLuminaire
Article 100 – DefinitionsQualified Person
One who has the skills and knowledge related to the construction and operation of the electrical equipment and installations and has received safety training on the hazards involved.
10
Article 100 – Definitions
l “That which is built or constructed”
l Not previously defined in the NEC
l Compatible with other building codes and standards
Structure
110.12(A) – Mechanical Execution of Work
l Combines the requirements in Article 110 with the requirements covering cabinets and cutout boxes
l Applies to boxes, raceways, auxiliary gutters, cabinets, cutout boxes, meter socket enclosures, equipment cases and housings
l Must be substantially equivalent to the wall of the equipment
l Metallic plugs in nonmetallic enclosures must be recessed at least 6 mm
Unused Openings
Box
Close all unused openings
11
110.14(C) – Electrical TerminationsTemperature Limitations
Ampacities for conductors at equipment terminations must be
based on Table 310.16
Ampacity of the conductor (for ambient adjustment and derating) is permitted to be based
on appropriate table (e.g. 310.17 for single conductors in free-air)
110.15 (new)
l New section added to require the marking of the high- leg of a 4-wire delta connect system with orange color or other effective means
l Identification required at each point on the system where a connection is made if the grounded conductor is also present
High-leg Marking
208V
120V120V
12
110.16 (New)Flash Protection
Switchboards, panelboards, industrial control panels, and motor control centers that are likely to be worked on while energized
Field Marked with a label to warn of potential electric arc flash hazards
Equipment in dwelling units is not included in the requirement
DANGER Arc -Flash Hazard
Protective Equipment requiredin accordance with NFPA 70E
Failure to use proper equipment can result in serious injury or death
110.26(C)(2) – Entrance to Working SpaceLarge Equipment
Equipment over 1200A and over 6 feet wide
Where the entrance to the space has a personnel door, it must open in the direction of egress and be equipped with panic bars, pressure plates, etc.
Similar rule for over 600V equipment in 110.33
13
110.26(F) – Spaces about Electrical EquipmentDedicated Equipment Space
Dedicated space extends 6 feet above the height of the equipment. Only electrical equipment allowed in this space.
Space is the same width and depth as the equipment.
Piping
Space above the dedicated space up to the structural ceiling is permitted to have foreign systems, provided protection from leaks or breaks is provided
Drip protection
110.31
l Fence shall not be less than 7ft in heightl Table 110.31 Minimum Distance from Fence to Live Partsl Does not apply to enclosed equipment
Nominal Voltage m ft601 - 13,799 3.05 10
Minimum Distance to
Live Parts
13,800 -230,000 4.57 15Over 230,000 5.49 18
Enclosure for Electrical Installations
14
110.58 – Tunnel Installations over 600V
l A switch or circuit breaker shall be installed within sight of each transformer or motor location to serve as the disconnect.
Disconnecting Means
200.6
l The word “natural” has been deleted from “natural gray”
l Gray conductors are now permitted as grounded conductors
l Allows “gray” to be used for an ungrounded conductor to distinguish one system from the othern e.g. white for 120/240V and gray for
480Y/277V
Means of Identifying Grounded Conductors
15
210.6(E) – Voltage LimitationsOver 600 Volts Between Conductors
Over 600V circuits can supply utilization equipment in installations where conditions of maintenance and supervision ensure that qualified persons will service the installation.
4160V Compressor
210.7Branch Circuit Receptacle Requirements
1999 NEC
210-7 covered:
•Requirements for grounding type receptacles
•Methods of grounding receptacles
•Replacement of receptacles
Moved to
New Article 406 covering
Receptacles
16
210.7(C) – Receptacle RequirementsMultiple Branch Circuits
N
ØØ
More than one receptacle on a yokeSupplied by more than one branch
circuit (can be multiple single circuits or a multi-wire circuit)
Must be provided with a means to simultaneously disconnect the ungrounded conductors at the panelboard where the circuits originate
210.8(A)(5) Exception No. 3 – Dwelling UnitsUnfinished Basements
Fire and/orBurglar AlarmControl Panel
Receptacle supplying only a permanently installed fire alarm or burglar-alarm
Remove tab to limit to one receptacle
Omission of GFCI protection
17
210.8(A)(8) – Dwelling UnitsBoathouses
15- and 20-ampere receptacles in boathouses on dwelling unit property are required to have GFCI protection.
Article 555 now excludes private, noncommercial docking facilities for single-family dwellings
210.8(B)(3) – Other than Dwelling Units
GFCI protection now required for 15 and 20A receptacles in kitchens located in other than dwelling unit
Kitchens
18
210.12Arc-Fault Circuit-Interrupter Protection
Requirements:
• All branch circuits supplying 15 or 20A outlets in the bedroom
• NOTE: see definition of “outlet” in Article 100, this includes lighting outlets
• AFCI must be listed to provide protection of the entire branch circuit
210.19(B) – Minimum Ampacity and Size
l Ampacity in accordance with Table 310.15 and 310.60
l Size conductors at not less than 125% of the “designed potential load” of equipment to be operated simultaneously OR
l Sized by the engineer for supervised installationsn Design and installation are under
engineering supervisionn Qualified persons with documented training
and experience in over 600V systemsprovide maintenance, monitoring, and servicing of equipment
Branch Circuits Over 600 Volts
19
210.23
l No change to the code languagel Panel Statement is significant:
n The 80% limitation on any single cord- and plug-connected appliance on a circuit with two or more receptacles applies to both continuous or intermittent loads
Permissible Loads
210.52
Modified to indicate this section provides requirements for 125-volt, 15 and 20 ampere receptacle outlets.
Dwelling Unit Receptacle Outlets
20
210.52(C)Countertops
Receptacle installed in appliance garage does not count as one of the required outlets.
Must be not more than 24” to meet 210.52(C)(1)
210.52(C)(5) Exception - CountertopsReceptacle Outlet Location
Not more than 20”
Where a receptacle is mounted above the cabinets, it must be within 20” of the countertop to be counted as one of the required receptacles.
21
210.52(D)
l Receptacle now permitted to be installed on a partition or a wall
l Wall or partition must be “adjacent” to the basin or basin countertop
l The receptacle must be within 3 feet of the outside edge of the basin
Bathrooms
Wall
Half-wall or partition
210.52(G)
Finished Basement -normal receptacle
placement
Unfinished portion
GFCI Protected
Unfinished portion
GFCI Protected
A receptacle must be placed in each unfinished portion of the basement
Basements
22
210.63Heating, AC, and Refrigeration Equipment Outlet
25’ max
Receptacle required within 25’ of all heating, AC or refrigeration equipment regardless of the type of installation
210.70(A)(2)(c) – Dwelling Units
Switch required at landing level if there is an entry at the landing.
Lighting Outlet Switch Locations
23
215.2(B) – Minimum Rating and Size
l Ampacity in accordance with 310.15 and 310.60l Transformers – conductors supplying transformers shall not
be less than the nameplate rating of the transformerl Transformers and utilization equipment - Size conductors at
not less than 125% of the “designed potential load” of equipment plus the nameplate ratings of the transformersOR
l Sized by the engineer for supervised installationsn Design and installation are under engineering supervisionn Qualified persons with documented training and experience in over
600V systems provide maintenance, monitoring, and servicing of equipment
Feeders Over 600 Volts
225.26Vegetation as Support
Support of overhead conductor spans by vegetation is not permitted. The exception for temporary wiring has been deleted.
24
230.6Conductors Considered Outside the Building
Installed under not less than 2” of concrete beneath a building or structure
Installed in conduit and under not less than 18” of earth beneath a building or structure
Encased in not less than 2” of concrete or brick
Installed in a vault that meets Article 450 Part III
230.40 Exception No. 1 – Service Entrance ConductorsNumber of Service Entrance Conductor Sets
Occupancy #1 Occupancy #2 Occupancy #3
240V Service 480V Service
Permits a set of service entrance conductors run to each occupancy for each service of different characteristics as defined in 230.2(D)
25
230.70(A)(3) - LocationRemote Control
Shunt trip or “remote control”
The service equipment must still be located at a readily accessible location where the conductors enter the building
230.82
l Additional Equipment n Meter socketsn Meter disconnect switches rated 600
Volts maxn Fuel Cell Systems
l Surge Protective Devices removed from list of permitted devicesn Surge Arresters are still included in the
permitted list of devicesn Removed in order to clarify TVSS
products are not permitted
Equipment Connected to the Supply Side of Service Equip
On to service equipment
Meter disconnect switch
480Y/277V Typical
Supply
26
230.212
l Section previously applied when voltage exceeded 15,000 volts
l Where service conductors enter a building they must terminate in metal-enclosed switchgear compartment or a vault complying with Article 450 Part III
Over 35,000 Volts
240.2
l Coordinationn The proper localization of a fault condition to restrict outages to the
equipment affected, accomplished by the choice of selective fault-protective devices
l Current limiting overcurrent protective devicen Moved from 240.11
l Supervised industrial installationn Moved from 240.91
l Tap conductorsn Moved from 240.3(D)n Clarified to exclude service conductors
Definitions
27
240.21(B)(5)(4)c – Feeder TapsOutside Taps of Unlimited Length
Feeder Tap
Conductors installed in accordance with 230.6
Equipment at a readily accessible location where the conductors enter
240.21(C)(6) – Transformer Secondary Conductors
Primary conductors protected at their ampacity
25’ max
Conductors terminate in a single CB or set of fuses that limit load current to the ampacity of the secondary conductors
Secondary conductors have an ampacity that is at least 1/3 the rating of the primary device when multiplied by the voltage ratio
480V 240V
Secondary Conductors Not Over 25’ Long
200A
150A
150A conductors
28
240.24(B) Exception No. 2 – Location In Premises
l General rule requires that each occupant have ready access to overcurrent devices that supply that occupancy
l Exception recognizes that occupants of hotel/motel rooms do not need access if the building is under continuous building management supervision
Occupancy
240.83(D) - Marking
l Requires a breaker listed and marked as HID (high intensity discharge) to be used as a switchfor HID lighting
l Florescent lighting can be switched with breakers marked SWD or HID
Used as Switches
29
240.85 – Circuit Breakers
Clarifies that “slash” rated breakers should be applied only in solidly grounded circuits
Applications
Slash Rated Breaker OK
Article 240 Part VIIISupervised Industrial Installations
Conditions of maintenance and engineering supervision ensure that only qualified persons monitorand service the system
System has at least 2500 kVA of load used in industrial process and/or manufacturing (calculated in accordance with Article 220)
At least one service more than 150V to ground and 300V phase-to-phase
Does not apply to offices, garages, warehouses, etc.
30
240.92(B)(1)(1) – Transformer Secondary ConductorsShort-Circuit and Ground-Fault Protection
Secondary conductor length changed from 50 feet to 100 feet
Primary overcurrent device not more than 150% of the secondary conductor ampacity multiplied by the secondary to primary voltage ratio
See 240.92(B)(2) for overload protection requirements
240.92(B)(1)(2) – Transformer Secondary Conductors
Differential Relay
Short-Circuit and Ground-Fault Protection
Conductor secondary is now permitted to be of any length
See 240.92(B)(2) for overload protection requirements
31
240.92(B)(1)(3) – Transformer Secondary ConductorsShort-Circuit and Ground-Fault Protection
Secondary conductor length limitation removed
Secondary conductors considered protected if calculations made under engineering supervision determine that the system overcurrent devices will protect the conductors within the recognized time-current limits for ALL short-circuit and ground-fault conditions.
240.92(D) – Location in Circuit
l Secondary conductors are permitted to be protected by the primary overcurrent device
l Primary device time-current characteristics multiplied by the effective primary to secondary voltage ratio must effectivelyprotect the secondary conductors
l Difficult to use with transformers that have greater than a 1:1 ratio of primary L-L voltage to secondary L-L voltage
Protection by Primary Overcurrent Device
32
250.4(B) – General Requirements for Grounding
l Material moved from 250.2 where it was mixed with grounding system requirements
l Ground all non-current carrying conductive materials of electrical equipment
l Bond together all non-current carrying conductive materials together to create a permanent, low-impedance path for ground-fault current
Ungrounded Systems
1st fault grounds the system
250.20
l Specifies what systems are required to be grounded
l Notes that other systems are permitted to be grounded
l Now clarifies that if a system is grounded (either required or permitted) the grounding must comply with Article 250
AC Circuits and Systems to Be Grounded
33
250.30(A)(2)(b) and (3) – Sep Derived Systems
l Allows a common grounding electrode for multiple separately derived systems
l Must use exothermic weld, irreversible compression or connect to copper bus bars
l Keep main grounding electrode conductor without a splice or joint
Grounding Electrode Conductor
Grounding Electrode (example shown is water pipe)
Separately Derived Systems
Size common grounding electrode conductor based on 250.66 using the total area of largest derived phase conductor from each system
Size “tap” conductors based on 250.66 based on the derived phase conductor size
250.32(E) – Two or More Buildings/Structures
Service Equip - Bldg #1 Bldg #2Grounding Electrode Conductor
Grounding electrodeconductor sized by 250.66 based on largest ungrounded supply conductor.
34
Article 250
l 250.52 establishes the electrodes PERMITTED for groundingn Metal underground water pipen Metal frame of the building or structuren Concrete encased electroden Ground ring
n Rod and Pipe electrodesn Plate electrodesn Other local metal undergrounds systems
or structures
l 250.52(B) establishes electrodes NOT permitted for groundingn Metal underground gas pipingn Aluminum electrodes
Part III – Grounding Electrode system
Gas Pipe
250.53(C) – Grounding Electrode System InstallationBonding Jumper
• Install – 260.64(A), (B) and (E)• Size - 250.66• Connect – 250.70
35
250.102(E) – Equipment Bonding JumperInstallation
Rigid nonmetallic conduit
Rigid metal conduit
Equipment bonding jumper permitted longer than 6’ permitted to bond isolated sections of metal raceways
250.104(A) – Bonding of Piping SystemsMetal Water Piping
Requires bonding of water pipe that is “installed in” or “attached to” a building or structure.
“Installed in”
“Attached to”
36
250.104(B)
l Deleted old 250-104(c) that required bonding of all metal gas piping to the grounding electrode
l Gas piping now covered under 240.104(B) which requires bonding of piping that is “likely to become energized”.
l Bonding jumper sized based on the overcurrent device protecting the circuit that is likely to energize the piping.
l The equipment grounding conductor of the circuit is permitted to serve as the bonding means
Bonding of Other Metal Piping
Branch Circuit
Gas Piping
250.122(B) – Equipment Grounding Conductors
Now requires proportional increase in equipment grounding conductor when phase conductors are increased for any reason.
Increase in Size
37
250.146(A)Surface Mounted Box
Box must be mounted “on” the surface
Direct metal to metal contact acceptable for grounding the receptacle
Previous code allowed a box mounted “at” the surface to use metal to metal contact. Now a yoke must be listed to establish the grounding path for other than surface mounted boxes.
Article 285
l Service. The TVSS shall be connected on the load side of a service disconnect overcurrent device
l Separately Derived System. The TVSS shall be connected on the load side of the first overcurrent device in a separatelyderived system.
l Short Circuit Current Rating. The TVSS shall not be installed at a point on the system where the available fault current exceeds the marking on the equipment.
Transient Voltage Surge Suppressors (TVSS)
38
285.1 - TVSS
l Covers n general requirementsn installation requirementsn connection requirements
l Permanently installed only
Article Scope
285.3 - TVSS
l Circuits exceeding 600 volts.l Ungrounded electrical systems as
permitted in Section 250.21.l Where the rating of the TVSS is less
than the maximum continuous phase-to-ground power frequency voltage available at the point of application.
Uses Not Permitted
39
285.5 - TVSS
l The TVSS shall be Listed. l Most TVSS products will reference:
n UL 1449 2nd Edition on the product.
Listing
285.6 - TVSS
l The TVSS shall be marked with a short circuit current rating... n DO NOT confuse the Short Circuit Current Rating (SCCR) with the
Surge Current (Capacity) Rating !!!u The Surge Current Rating is the maximum transient current level that can
be suppressed by the TVSS. u The Short Circuit Current Rating is the available and sustainable power
current level that can flow in the circuit, at the point of connection to the system, during a fault condition until the circuit is opened.
Short Circuit Current Rating
40
Chapter 3 Reorganization
305 527
Moving to
380 404
384 408
Articles Moving to Different Chapters
Chapter 3 Reorganization
l See new Annex F for cross-referencel Articles 312-314 covers boxes and enclosures
n Outlet boxes, cabinets, etc.
l Articles 320-340 covers cablesn MI, MC, AC, NM, UF, etc.
l Articles 342-356 covers conduitsn RMC, RNMC, FMC, etc.
l Articles 358-362 covers tubingn EMT, ENT, FMT, etc.
l Articles 366-390 covers other methodsn Busway, cable bus, etc.
l Articles 392-398 covers open wiringn Knob and tube, open wiring on insulators, etc.
Wiring Method Article Renumbering
41
Chapter 3 Reorganization
.1 Scope
.2 Definitions
.6 Listing RequirementsPart B Installation.10 Uses Permitted.12 Uses Not Permitted.16 Temperature Limits.30 Securing and Supporting.60 GroundingPart C - Construction Specifications.110 Corrosion Protection.120 Markings
Common Number Method for all articles
300.1(C)
615551294103
3 ½91378
2 ½63253
1 ½41
1 ¼35127¾21½163/812
Trade SizeMetric DesignatorNeither the metric designator nor the trade size relate to actual dimensions of the conduit or tubing.
Metric Designators and Trade Sizes
42
300.4(B)(1) – Protection Against Physical Damage
Metal Stud
A listed bushing or grommet must cover all metal edges and be securely fastened to the opening
NM Cable and EMT Through Metal Framing Members
300.5(D)(3) – Underground Installations
18” or more18” or more
Applies to all underground service conductors
Service Conductors
At least 12” Warning Ribbon
43
300.5(K) – Protection Against Physical DamageDirectional Boring
Cables and raceways installed using directional boring equipment shall be “approved” for the purpose.
300.6(A) – Protection Against Corrosion
Where threads are cut in the field, the threads shall be coated with an approved, electrically conductive, corrosion resistant compound.
General
Located in an area where corrosion protection is necessary
44
300.7(A) – Raceways Exposed to Different Temperatures
Sealing
Interior - 72°FExterior - 25°F
Fill raceway with approved material to prevent circulation of warm air to cold air region
Raceway
300.11(C) – Securing and SupportingCables Not Used as Means of Support
Cable wiring method (e.g. MC cable)
Other cable or raceway (e.g. Class 2 circuit)
Cable wiring methods are not permitted to support other cables or raceways
45
300.22(B) – Wiring in Ducts, Plenums or Other Spaces
Change specifically prohibits conduit with an overall nonmetallic coating
Ducts or Plenums Used for Environmental Air
Ducts or plenums in 300.22(B) are those specifically fabricated to transport environmental air.
300.22(C) – Other Spaces Used for Env AirWiring Methods
Return Air SpaceSuspended ceiling
Rigid metal conduit with a nonmetallic coating now prohibited
46
310.15(B)(2) – Exception No. 5Adjustment Factors – AC or MC Cable
MC or AC cable
• #12 AWG conductors
• Not more than 3 current carrying conductors per cable
• No overall outer jacket
No adjustment factor required where not more than 20 current carrying conductors are in the stack or bundle.
For more than 20 current carrying conductors, a 60% adjustment factor applies
Table 312.6(B)Minimum Wire Bending Space at Terminals
The table now recognizes smaller wire bending space for compact stranded AA-8000 aluminum conductors
Using an example of a 400A circuit:
1999 NEC
Cu – 3/0 - 6 ½ inches
Al – 250 kcmil – 8 ½ inches
2002 NEC
Cu – 3/0 - 6 ½ inches
Al – 250 kcmil – 6 ½ inches
47
314.20
Surface of concrete, tile, gypsum, plaster or other noncombustible material
In Wall or Ceiling
Box not set back more than ¼” from the finished surface
For surfaces of wood or other combustible material, the box must be flush with the finished surface
314.23(B)(1) – Structural MountingNails and Screws
Where nails or screws are used to fasten a box, the nail or screw must pass thru a bracket outside of enclosure or must pass through the inside with ¼” of the back of the enclosure.
48
314.27(A) ExceptionBoxes at Luminaire Outlets
Permits mounting of luminaire to a “standard” outlet box where the luminaire does not weigh more than 6 lb. Dimensional limitation on the fixture has been removed.
Use #6 screws minimum
Maximum Luminaire Weight
Luminaire weighing not more than 50 lbs.
Outlet box identified for luminaire (fixture) support
Luminarie’s weighing over 50 lbs must be supported independently of the outlet box
314.27(B) – Outlet Boxes
49
330.10(13) – Uses PermittedSingle-Conductor MC
Where single conductor MC is used, the phase and neutral (if used) conductors shall be grouped together to minimize induced voltage
Single-conductor MC is required to have a nonmagnetic sheath or armor (NEC 330.116)
Installation of single-conductor MC must comply with NEC 300.20.
332.80 – AmpacitySingle Type MI Conductors Grouped Together
Open runs or on a messenger in a triangle or square configuration
Permitted to use Table 310.17 ampacities for the MI cable.
Temperature limitation of equipment terminations must be considered. Ampacity will be required to be reduced back to Table 310.16 levels before terminated within equipment.
Not less than 2.15 times diameter of largest conductor in the group
50
334.6 – NM CableListed
NM Cable is required to be listed
334.10(2) – NM CableUses Permitted
Multifamily dwellings and other buildings that are of Type III, IV or V construction.
New Appendix E will contain a table from NFPA 220 to explain the different building Types
The building code in effect locally will also define the building types
In general, this permits NM to be used in 4-story apartment buildings (typically R-2 buildings, Type III and IV)
51
Annex E
l Type III – typically constructed of noncombustible, limited-combustible, or other approved combustible material
l Type IV – typically timber frame construction
l Type V – typical stick built construction
Types of Construction
Explanation of Headers – Example = 211 Construction
2 = 2 hr fire rating of exterior load bearing walls
1 = 1 hr fire rating of columns, beams, girders that support bearing walls or loads from more than one floor
1 = 1 hr fire rating of floor
334.12(A)(1) – Uses Not PermittedTypes NM, NMC and NMS
Space above suspended ceiling in other than one, two and multi-family locations
NM cable not permitted in this space
52
338.10(B)(4) – Uses Permitted
l Applies installed as a branch circuit or feeder
l Must be installed in accordance with Article 334 (NM Cable) Parts I and II
l Specifically excludes 334.80 requirement that limits ampacity of NM cable to 60C
Installation Methods for Branch Circuits and Feeders
342.22Number of Conductors
IMC
Conductor fill must comply with Table 1, Chapter 9
Cables are permitted to be installed where such use is permittedby the respective cable articles.
53
344.24
l One shot and Full shoe benders contained in one table
l Minimum radius is now measured to the centerline of the conduit
Bends – How Made
362.10(2) Exception – InstallationUses Permitted
ENT
NFPA 13 sprinkler system throughout the building15 minute finish rating not
required
54
400.8(5)
Flexible cord not permitted above a suspended or drop ceiling
Uses Not Permitted
404.6(C)
l General rules says that blades must be de-energized when in the open position
l New text recognizes that a bottom fed bolted pressure switch can have energized blades if barriers are provided
Connection of Switches
55
404.8(B) – Accessibility and Grouping
l Applies to switches grouped in an enclosure with other switches, receptacles or similar devices
l Voltage between adjacent devices must not exceed 300V
l A permanently installed barrier can be used to separate devices where the voltage does exceed 300V
Voltage Between Adjacent Devices
404-14(E)Dimmer Switches
Dimmer switches are permitted to supply only permanently installed incandescent luminaries, unless listed for the control of other loads.
56
404.15(B) – MarkingOff Indication
OffAuto
On
If a switch has a marked off position, it shall disconnect all ungrounded conductors
406.4(E)Receptacles in Countertops and Similar Work
Surfaces in Dwelling Units
Receptacles not permitted to be mounted face-up in any countertop or work surface in a dwelling unit
57
406.8(B)(1)15- and 20-Ampere Outdoor Receptacles
Requires the use of a “weatherproof” while in use cover in all outdoor wet locations.
Applies to 15 and 20 ampere, 125 and 250-volt receptacles
406.8(B)(2)Other Receptacles
Requires the use of a “weatherproof” while in use cover in all outdoor wet locations where the product intended to be plugged in is not attended while in use (e.g. sprinkler controllers, landscape lighting, holiday lighting, etc.
For applications where the plugged in equipment will be attended while in use (e.g portable tools), a basic weatherproof cover can be used.
Applies to receptacles other than 15 and 20 ampere, 125 and 250-volt
58
408.4
l All circuits or circuit modifications shall be legibly identified as to their purpose
l Located on the panel face or inside the panel door
l Located at each switch on a switchboard
Circuit Directory
Now applies to both switchboards and panelboards!
408.21
l Each grounded conductor must terminate in an individual terminaln Do not put two “neutrals” in
one terminaln Do not put a neutral and an
equipment ground in one terminal
l Multiple equipment grounding conductors can still be terminated in a terminal if the panel is identified to allow the multiple connection
Grounded Conductor Terminations
59
410.18(B) Exception – Exposed Luminaire Parts
Grounding means not available at the outlet
Grounding Electrode
Separate equipment grounding conductor installed in accordance with 250.130(C)
Replacement luminaire. Permitted to have conductive parts.
Made of Insulating Material
430.32(C) – Continuous Duty MotorsSelection of Overload Relays
Clarifies that the sensing element or the setting of the overload relay can be increased if the values in 430.32(A) and (B) are not sufficient to start the motor.
NA130% to 140%430-32(A) and (B)
430-32(C)
Approved for use with the motor
115% to 125%One HP or less, automatically started
430-32(B)
140% to 170%115% to 125%More than 1HP430-32(A)
Thermal Protector
Sep Overload DeviceCoversNEC
NA130% to 140%430-32(A) and (B)
430-32(C)
Approved for use with the motor
115% to 125%One HP or less, automatically started
430-32(B)
140% to 170%115% to 125%More than 1HP430-32(A)
Thermal Protector
Sep Overload DeviceCoversNEC
60
430.52(C)(1) – Rating or SettingIn Accordance with Table 430.52
Table moved from 430-152 to become Table 430.52
430.53(D) – Several Motors or LoadsSingle Motor Taps
Listed manual motor controllers additionally marked “suitable for tap conductor protection in group installations”
Group Installation: multiple motors installed on one branch circuit
Branch short-circuit/ground-fault device
Conductors not less than 1/10 the rating of the branch SC/GF device Conductors sized by
430.22
Not more than 10’ in length
61
430.62(A) Exception No. 2 – Rating or SettingSpecific Load
Feeder overcurrent device supplying a Motor-Control Center
Feeder device must have a rating or setting that does not exceed the rating of the MCC main power bus (see 430.92)
430.102(B) – Disconnect LocationMotor
430.102(A) requires the disconnect in sight of the controller
430.102(B) requires a disconnect in sight of the motor
430.102(B) Exception allows omission of the disconnect in sight of the motor if one of the following applies:
(a) the location is impracticable or introduces additional hazards
(b) Industrial installation with maintenance and supervision and written safety procedures
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430.102(B) Exception
l Where the exception is used to eliminate the disconnect at the motor the controller disconnect must ben Capable of being locked in the open
positionn Each disconnect must be
individually lockable
n The locking means must be permanently installed on or at the switch or circuit breaker
Motor Disconnect
440.65 – Room Air Conditioners
l Single-phase cord- and plug-connected room air conditioners
l Must be provided with factory- installed n LCDI (Leakage Current
Detection and Interruption)n or AFCI (Arc-Fault Circuit
Interrupter)
LCDIMust be integral with the attachment cap or located within 12” of the attachment cap
LCDI or AFCI Protection
63
500.7(K) – Protection Techniques
Detection system restrictions:l In industrial establishments with restricted
public access andl Where conditions of maintenance and
supervision ensure only qualified persons service installation
l System is listed for detection of specific gas or vapor
Permitted equipment with detection system:
l Inadequate Ventilation establishes Class I, Div. 1 location– Electrical equipment suitable for Class I, Div. 2
l Interior of Building with opening into Class I, Div. 2 – Electrical equipment for unclassified locations
l Interior of Control Panel – Instrumentation measuring gas– Electrical equipment suitable for Class I, Div. 2
Combustible Gas Detection System
500.8(A)(1) – Suitable for Class and Properties
l Suitability of Identification byn Equipment listing or labelingn Evidence of equipment
evaluation from a qualified testing lab or inspection agency
n Evidence acceptable to the AHJ such as a manufacturer’s self-evaluation or owner’s engineering judgment
Identified
64
501.4(B)(3) – Class I Division 2Nonincendive Field Wiring
Unclassified LocationClassified Location
Nonincendive field wiring –not capable of igniting (through arcing or thermal effects) flammable gas or vapor under normal operating conditions.
Nonincendive field wiring apparatus
• Install in accordance with the control drawings
• Install in separate cables, cables where each conductor has a grounded metal shield or in multi-conductor cables where each conductor has a min of .25mm of insulation
Cable or wiring method permitted for unclassified location
504.80(B) – Intrinsically Safe Systems
l Labels located at least every 25 feetl Visible after installationl Must appear in every section separated by walls, partitions,
etc.
Identification of Wiring
Intrinsic SafetyWiring
65
511.1 – Commercial GaragesScope
l Includes locations used for service and repair operations
l Self-propelled vehiclesl Flammable liquids or
flammable gases used for propulsion
511.3(B)(2) – Classified LocationsWithin 18” of the Ceiling
Class I Division 2 unless provided with four air changes per hour
CNG Vehicle
18”
66
Articles 513 and 515
Div 1
Div 2
Zone 0
Zone 1
Zone 2
Article 513Aircraft Hangers
Article 515
Bulk Storage Plants
Zone Classification
Zone classification system now permitted
514.1 – Motor Fuel Dispensing FacilitiesScope
Scope and title changed from “Gasoline Dispensing” to “Motor Fuel Dispensing”
Now includes: gasoline, LNG, CNG, etc.
67
517.2 – Definitions
l Definition correlates with NFPA 99l Buildings or portions of buildings that include:
n Medicaln Dentaln Psychiatricn Nursingn Obstetricaln Surgical
l Includes (but not limited to):n Hospitalsn Nursing homesn Limited care facilitiesn Clinicsn Medical and dental officesn Ambulatory care
Health Care Facilities
517.18 – Tamper Resistant Receptacles
l Applies to ALL receptacles in patient care areas of pediatric wards, rooms or areas
l Listed tamper resistant receptacle, or l Listed tamper resistant cover
Pediatric Locations
68
517.30(E) – Essential Electrical Systems
Identification required for receptacles supplied from the emergency system.
Identification shall be of the cover plate or the receptacle itself.
Distinctive color or marking so as to be readily identifiable
Receptacle Identification in Hospitals
Similar requirement exists for emergency receptacles in nursing homes and limited care facilities [see 517.41(E)]
517.32(G) – Life Safety BranchAutomatic Doors
Connect to the life safety branch
Automatically operated doors used for building egress
EXIT EXIT
69
517.34 ExceptionEquipment System Connection to Alternate Power Source
Requirement for time-lag interval for the equipment system is not required for essential systems of less than 150kVA
Omission of the time-lag interval allows a single transfer switch to be used
520.1 – TheatersScope
Scope now includes performance areas and applies to both indoor and outdoor locations
70
Article 527Temporary Installations
Temporary Wiring has been renamed Temporary Installations
The article covers more than just wiring methods allowed. GFCI’s, receptacle grounding, disconnecting means, etc. are also covered.
527.3(B) – Time Constraints90 Days
The new wording now reflects that the 90 day time limit applies to all holiday wiring, not just Christmas.
71
527.6(A) – Ground-Fault Protection for Personnel
l GFCI Protection Required for all 125-volt, 15, 20 and 30 ampere receptacle outletsn Used by personnel during construction, remodeling, maintenance,
repair or demolitionn GFCI in cords sets is acceptable
l Exception for Industrial establishments wheren Qualified personnel are involvedn Assured Equipment Grounding Conductor Program is applied
n Only permitted for receptacle outlets where having GFCI protection would be a greater hazard or equipment is not compatible with GFCI protection
Receptacle Outlets
527.6(B) – Ground-Fault Protection for Personnel
l Applies to all receptacles other than 15, 20 and 30-ampere 125-volt
l Requires eithern GFCI, orn Assured Equipment Grounding Conductor Program [527.6(B)(2)]
Use of Other Outlets
72
547.5(G) – Wiring Methods
l Requires GFCI protection on all 125-volt, 15 and 20-ampere general purpose receptacles installed inn Areas having an equipotential planen Outdoors
n Damp or wet locations
Receptacles
547.9 – Power DistributionElectrical Supply to Buildings/Structures from Distribution Point
Site isolating device (may be a pole-top disconnect)
Disconnects permitted to be located at distribution point – treat like a feeder (250.32 and Article 225)
Alternatively, disconnects may be located at the buildings instead of the distribution point –547.9(B)(1)
73
547.10
l Required where the following existn Concrete floor of
confinement arean Animals have access to
metal equipmentn The metal equipment is
likely to become energized
l Must be bonded to the electrical grounding system
Equipotential Plans and Bonding of Equipotential Planes
550.25(B) – AFCI Protection
l Requires AFCI protection on branch circuits that supply 15 and 20 ampere, 125 volt outlets in bedrooms
l Parallel with 210.12 requirementl HUD rules govern the construction of
manufactured homes. HUD does not yet include the AFCI requirement.
Bedrooms of Mobile Homes and Manufactured Homes
74
Article 555
l Revised to be more consistent with NFPA 303 –Fire Protection for Marinas and Boatyards
l Specifically excludes private, noncommercial docking facilities associated with single-family dwellings
l Relates electrical requirements to the “electrical datum plane”n 2 ft above highest tide level for area under normal
circumstances
n 2 ft above highest water level under normal circumstances
n 30” above water level at floating pier or landing stage and a minimum of 12” above the level of the deck
Marinas and Boatyards
555.19 – Receptacles
l Receptacles for shore power must ben Not less than 30 ampsn single outlet type
l Receptacles that are 30 to 50 amps must be of the locking and grounding type
l Receptacles 60 to 100 amperes must be of the pin and sleeve type
l GFCI protection required for receptacles other than shore power locatedn Outdoorsn In boathousesn Buildings used for storage, maintenance or repair
where electrical hand tools or diagnostic equipment are to be used.
Shore Power and Other than Shore Power
75
600.21(F) – Ballasts, Transformers and…
Support wires
Suspended Ceilings
Power supply for electric sign
Flexible cord not permitted
Securely supported in place and not dependent on suspended ceiling grid for support
604.6(E) – Construction
New requirement clarifying that manufactured wiring systems shall be supported in accordance with the applicable cable or conduit article.
Support
76
645.5(D)(5)(c) – Under Raised Floors
l Type ITC Cable is now permitted under raised floors to supply IT equipment.
l Equipment grounding conductor may be either green insulation or green insulation with one or more yellow stripes
l Driven by more use of computer systems in instrumentation and control of industrial locations
ITC Cable
645.5(D)(6) – Under Raised Floors
Abandoned cables beneath a raise floor assembly shall be removed unless contained within a metal raceway.
Abandoned Cables
77
Article 647
l New Articlel Material from Part G of Article 530l Covers the installation and wiring of
separately derived systems operating at 120V line-to-line and 60V to ground for sensitive electronic equipment
l Expands the permitted use of this system outside television and motion picture venues.
Sensitive Electronic Equipment
60V
120V
60V
Article 680
l Article completely revisedl Part I – Generall Part II – Permanently Installed
Poolsl Part III – Storable Poolsl Part IV – Spas and Hot Tubsl Part V – Fountainsl Part VI – Pools and Tubs for
Therapeutic Use
Swimming Pools, Fountains, and Similar Installations
78
680.6
“Pool” changed to “specified body of water”n Grounding requirements for all bodies of water covered
under the scope of 680 now grouped in 680.6
Grounding
680.12
Maintenance disconnect within sight of the electrical equipment (not the pool or spa itself)
5ft minimum distance from pool moved to 680.22(C)
Maintenance Disconnecting Means
79
680.23(F)(1) Exception – Branch-Circuit Wiring
LFNC-B permitted to be used in lengths longer than 6ft where connecting a transformer to pool lights.
X-fmr
Wiring Methods
680.26(B)(1) – Bonded Parts
l Basic rule requires bonding of steel structure of a pool (i.e. rebar)
l If rebar is insulated by encapsulation it is not be required to be bonded
l Provisions shall be made for an alternate means to eliminate voltage gradientsn Example: installation of a #8
AWG bare copper conductor throughout the structure
Metallic Structural Components
80
680.26(B)(4) – Bonded Parts
l Basic rule requires bonding of all equipment associated with the circulating system
l Double insulated pumps are permittedl Where a double insulated pump is installed, a #8 AWG
bonding conductor is required at the pump location for use with a replacement motor.
Double-insulated motor
No. 8 copper
Electrical Equipment
680.27(B)(1) – Electrically Operated Pool CoversMotors and Controllers
Controls for an electrically operated pool cover shall be located so that the operator has full view of the pool
81
680.44(B) – Spas/Hot Tubs – Protection
GFCI protection required for outlets that supply a:
• self-contained spa or hot tub
• packaged spa or hot tub
• field assembled spa or hot tub with a heater load of 50A or less
Listed assemblies with integral GFCI protection for all electrical parts do not require additional GFCI at the outlet.
A spa or hot tub rated greater than 250V or 3-phase shall not require GFCI protection.
Other Units
680.57(C)(2) – Location
Portable electric signs shall not be placed within the pool or fountain, or within 5 ft (1.52 m ) measured horizontally from the inside walls of the pool or fountain
5 ft
Portable Signs
82
Article 692Fuel Cells
Includes requirements for:
• Listing of the fuel cell
• Identification of multiple power sources
• Circuit requirements
• Etc.
700.12(B)(6) – Generator Sets
l Allows disconnect at a generator to also serve as the disconnect for a building or structure
l Comply with the following:n Generator disconnect must be readily accessiblen Must be “within sight” of the building (visible and
not more than 50 feet away)n Must still meet the requirements for a building
disconnect in Article 225 (e.g. 225.36 requires that disconnect be suitable for use as service equipment)
Outdoor Generator Sets
Similar language in 701.11(B)(5) for legally required systems
83
702.1 – Optional Standby Systems
l ... The systems covered by this article consist of those that are permanently installed in their entirety, including prime movers, and those that are arranged for a connection to a premises wiring system from a portable alternate power supply.
Scope
702.6
l Transfer equipment required forn permanently installed standby systems n and where an electric-utility supply is
either the normal or standby source
l Must prevent the inadvertent interconnection of supplies
l Supplementary overcurrent protective devices shall be part of a listed transfer equipment. n Not a substitute for branch circuit or
feeder overcurrent protection
l Comply with Article 705 if system will be operated in parallel
Transfer Equipment
84
725.3(A) – Locations and Other Articles
l References 300.17 for all of Article 725
l This extends the raceway wire fill restrictions to Class 2 and 3 circuits
l Applies Chapter 9, Table 1 through references
Number and Size of Conductors in Raceway
725.6
l Installed in a neat and workmanlike mannerl Support to structural componentsl Use proper straps, hangers or similar fittings
Mechanical Execution of Work
Class 1, 2 or 3 circuits
Support wires
85
725.52(A) Exception No. 2 – Load Side of Class 2 or 3
l Can reclassify Class 2 and Class 3 circuits as Class 1 circuits
l Must install as Class 1l Class 2 and Class 3 markings
required in Section 725-42 are eliminated
l Entire circuit is installed using the wiring methods and materials in accordance the requirements for Class 1 circuits
Class 1 Wiring Methods and Materials
800.48 – Communications Wiring within Buildings
New Exception 2: Conduit fill restrictions shall not apply.
Communications Raceways
86
Annexes
l Annex A – Product Standardsl Annex B – Application of 310.10(A) formulal Annex C – Conduit and Tubing Fill Tablesl Annex D – Examplesl Annex E – NFPA 220 Table for Building
Typesl Annex F – Chapter 3 Cross Reference from
1999 to 2002 NECl The Annex material is for information only
and is not part of the Code requirements
Square D Company
l The Codes and Standards group can offer on-site custom training on the NEC and related topics
l Our staff has extensive involvement in codes and standards development, interpretation and application
l Excellent resource for resolution of field issues
Codes and Standards
