 |
90.2 Scope of the NEC |
This subsection was revised to group similar types of installations together and to make it easier to read. The first sentence was revised to read:
. . . |
| |
90.2 Scope of the NEC |
The rule that exempts electric utilities from complying with the requirements of the NEC was revised to read: (B) Not Covered.
(5) E . . . |
| |
90.4 Enforcement (Inspection) |
The first paragraph of this section was revised to read:
This Code is intended to be suitable for enforcement by governmental bodies that ex . . . |
| |
Grounding Electrode Conductor |
The definition for “Grounding Electrode Conductors” was revised to read:Grounding Electrode Conductor. The conductor that . . . |
| |
Ground-Fault Circuit Interrupter |
The definition for “Ground-Fault Circuit Interrupter” was revised to read:
Ground-Fault Circuit Interrupter. A device int . . . |
| |
Luminaire |
A new definition was added to replace the NEC terms “fixtures” and “lighting fixtures.” This definition reads:
Lumi . . . |
| |
Qualified Person |
The definition of “Qualified Person” was revised to read:
Qualified Person. A person who has the skill and knowledge re . . . |
| |
110.12 Mechanical Execution of Work |
This rule was revised to read:
(A) Unused Opening. Unused cable or raceway openings in boxes, auxiliary gutters, cabinets, cuto . . . |
| |
110.14 Electrical Connections |
New text was added to clarify conductor sizing for terminals and it reads:
(C)Temperature Limitations
(1) Equipment Provisions. Th . . . |
| |
110.15 High-Leg Marking |
New rule added to cover the identification of the high-leg. This rule reads:
On a 4-wire, delta-connected system where the midpoint of one p . . . |
| |
110.16 Flash Protection |
A new Code section and two FPN’s were added to provide requirements for marking equipment where arc fault hazards may be present. The new secti . . . |
| |
110.22 Identification of Disconnecting Means |
The text was revised to read:
All installed disconnecting means must be legibly marked to indicate their purpose unless they are l . . . |
| |
110.26 Spaces About Electrical Equipment |
A new sentence was added, which addresses exit door requirements (panic hardware) for rooms containing large electrical equipment. This section now r . . . |
| |
110.26 Spaces About Electrical Equipment |
The intent of the requirements for "dedicated equipment space" located indoors was completely revised and the rule reads:
(F) Dedicated Equ . . . |
| |
200.6 Means of Identifying Grounded (neutral) Conductor |
The term "natural" was deleted and a FPN was added to this section. It reads:
(A) Identifying Grounded (neutral) Conductors 6 AWG or Small . . . |
| |
200.7 Use of Insulation of a White or Gray Color |
The term "natural" was deleted and a FPN added to this section to read:
(C) Circuits Over 50V. The use of white or natural gray in . . . |
| |
210.63 Heating, Air-Conditioning, and Refrigeration Equipment Outlet |
The words “on rooftops and in attics and crawl spaces” and the exception were deleted so that this rule would coordinate with the mechanic . . . |
| |
210.7 Branch Circuit Receptacle Requirements |
New text clarifies the requirement for simultaneously disconnecting the ungrounded branch circuit conductors.
(C) Multiple Branch Circuits. . . . |
| |
210.8 Ground-Fault Circuit-Interrupter Protection for Personnel |
New subsection was added to include boathouses.(A) Dwelling Units. GFCI protection must be provided for all 15 and 20A, single-phase . . . |
| |
210.8 Ground-Fault Circuit-Interrupter Protection for Personnel |
New subsection was added to include kitchens.
(B) Other than Dwelling Units. All 15 and 20A, single-phase, 125V receptacles instal . . . |
| |
210.12 Arc-Fault Circuit-Interrupter (AFCI) Protection |
The word "receptacle" was deleted and the words “listed device that protects the entire branch circuit” were added. This subsectio . . . |
| |
210.52 Dwelling Unit Receptacle Outlets |
The maximum distance the required receptacle for the counter surface can be above a dwelling unit kitchen counter surface was changed from 18 in. to 2 . . . |
| |
210.52 Dwelling Unit Receptacle Outlets |
This section was revised to read:
(D) Bathrooms. In dwelling units, at least one 15 or 20A, single-phase, 125V receptacle outlet . . . |
| |
210.52 Dwelling Unit Receptacle Outlets |
This section was revised to read:
(G) Basements and Garages. For a one-family dwelling, at least one 15 or 20A, single-phase 125V . . . |
| |
225.32 Disconnecting Means Location |
Exception No. 1 was revised to read:
The disconnecting means for a building or structure must be installed either inside or outside of the . . . |
| |
230.10 Vegetation as Support |
A new rule was added, which reads:Vegetation such as trees cannot be used for the support of overhead service conductors. Figure 230-1< . . . |
| |
230.50 Protection of Cables Against Damage – Above Ground |
Item (3) was revised from “rigid nonmetallic conduit” to Schedule 80 rigid nonmetallic conduit, so that this section reads:
|
| |
230.70 Service Disconnect - General |
New text was added and it reads:
(A) Location of Service Disconnecting Means
(3) Remote Control. Where a remote con . . . |
| |
240.2 Definitions |
The following definitions were added for Article 240:
Current-Limiting Overcurrent Protective Device. A current-limiting overcurre . . . |
| |
240.21 Location in Circuit |
A new subsection was added to read:
(C) Transformer Secondary Conductors
(6) Secondary Conductors Not Over 25 ft. Secondary condu . . . |
| |
240.33 Vertical Position |
This section was revised to read:
Enclosures for overcurrent devices must be mounted in a vertical position unless it is impracticable. Cir . . . |
| |
240.83 Marking |
This subsection was revised and it reads:
(D) Used as Switches. Circuit breakers used to switch 120V or 277V fluorescent lighting . . . |
| |
240.85 Applications |
The second paragraph was revised and a FPN was added to read:
A circuit breaker with a straight voltage rating (240V or 480V) can be used o . . . |
| |
240.85 Applications |
Author’s Comment: A 120/240V slash circuit breaker cannot be used on the high-leg of a solidly-grounded 120/240V delta system, because . . . |
| |
250.2 Definitions |
The following definitions were added to Article 250:
Effective Ground-Fault Current Path. An intentionally constructed, permanent, . . . |
| |
250.4 General Requirements for Grounding and Bonding |
Section 250-2 in the 1999 NEC was revised and relocated to 250.4. It now reads:
(A) Grounded Systems.
(2) Grounding of Electrical Equip . . . |
| |
250.4 General Requirements for Grounding and Bonding |
Section 250-2 in the 1999 NEC was revised and relocated to 250.4. It now reads:
(A) Grounded Systems.
(3) Bonding of Electrical Equipme . . . |
| |
250.4 General Requirements for Grounding and Bonding |
Section 250-2 in the 1999 NEC was revised and relocated to 250.4. It now reads:
(A) Grounded Systems.
(4) Bonding of Electrically Conductiv . . . |
| |
250.4 General Requirements for Grounding and Bonding |
(A) Grounded Systems.
(5) Effective Ground-Fault Current Path. Electrical equipment and other electrically conductive mate . . . |
| |
250.30 Grounding Separately Derived Alternating-Current Systems |
This Subsection was reworded and additional requirements added to contain the requirements for grounding multiple separately derived systems. This su . . . |
| |
250.32 Buildings or Structures Supplied with Feeder |
This subsection added a new requirement and it reads:
(B) Grounded Systems
(2) Grounded (neutral) Conductor. Where (1) an equipme . . . |
| |
250.32 Two or More Buildings or Structures Supplied with Feeder |
The rule now reads:
(E) Grounding Electrode Conductor. The size of the grounding electrode conductor for a buil . . . |
| |
250.50 Grounding Electrode System |
This section was completely revised to read:
If available on the premises at each building or structure, all of the electrodes identified i . . . |
| |
250.54 Supplementary Grounding Electrodes |
This section was revised to read:
Supplementary grounding electrodes can be installed and they can be connected to the equipment grounding . . . |
| |
250.102 Equipment Bonding Jumpers |
A new exception was added to this subsection and this subsection now reads:
(E) Installation. The equipment bonding jumper can be installe . . . |
| |
250.104 Bonding of Piping Systems and Exposed Structural Steel |
The word “interior” was deleted in this section. This section now reads:
(A) Metal Water Piping
(1) General Requirements.
|
| |
250.104 Bonding of Piping Systems and Exposed Structural Steel |
An exception was added to this section. This section now reads:
(A) Metal Water Piping
(4) Separately Derived Systems. To preve . . . |
| |
250.104 Bonding of Piping Systems and Exposed Structural Steel |
The word “interior” was deleted in this section. This section now reads:
(B) Other Metal Piping Systems. Interior Me . . . |
| |
250.104 Bonding of Piping Systems and Exposed Structural Steel |
The word “interior” was deleted and the sizing of the bonding jumper was changed from 250.122 to 250.66. This section now reads:
. . . |
| |
250.118 Types of Equipment Grounding Conductors |
This subsection was completely revised to read:
(11) MC Cable. The outer metal sheath of smooth or corrugated tube type MC cable can serv . . . |
| |
250.146 Connecting Receptacle Grounding Terminal to Box |
The first sentence of this rule in the 1999 NEC was revised to delete the words “or at.” This section now reads:
(A) Surface M . . . |
| |
250.148 Continuity and Attachment of Equipment Grounding Conductors to Metal Boxes |
This section was completely reworded to read:
Where circuit conductors are spliced, or terminated on equipment within a box, any separate . . . |
| |
285.1 Scope |
This Article covers the installation and connection requirements for TVSS that are permanently installed on premises wiring systems. Figure 285 . . . |
| |
285.21 Connection |
Where a TVSS is installed, it must be connected as follows:
(A) Location.
(1) Service Supplied Building or Structure. A TVSS can be . . . |
| |
300.4 Protection Against Physical Damage |
The word “listed” was added so that this subsection now reads:
(B) Through Metal Framing Members.
(1) Nonmetallic-Sheathed Ca . . . |
| |
300.5 Underground Installations |
Replace the word “service laterals” with “service conductors,” so that this section now reads:
(D) Protection from . . . |
| |
300.7 Raceways Exposed to Different Temperatures |
The requirement for sealing against the flow of warm air to a colder section was completely reworded to read:
(A) Sealing. Where po . . . |
| |
300.15 Boxes, Conduit Bodies, or Fittings – Where Required |
This subsection was completely revised to read:
(I) Enclosures. A box or conduit body is not required where a splice is made in a . . . |
| |
310.8 Locations |
The text was revised to read:
(D) Locations Exposed to Direct Sunlight. Insulated conductors and cables used where exposed to dir . . . |
| |
310.15 Ampacities for Conductors |
A new exception was added and it reads:
(B) Table 310.16 Ampacity
(2) Adjustment Factors.
(a) More than Three Current-Carrying Conductors . . . |
| |
314.22 Exposed Surface Extensions |
The text was revised to read:
Surface extensions from a flush-mounted box must be made by mounting and mechanically securing . . . |
| |
314.27 Outlet Boxes |
The exception to the rule that required boxes used at luminaire or lampholder outlets be designed for the purpose was revised to read:
(A) . . . |
| |
314.27 Outlet Boxes |
A new subsection was added and it reads:
(B) Maximum Luminaire Weight. Outlet boxes that are properly supported in accordance with . . . |
| |
314.27 Outlet Boxes |
This subsection was revised to read:
(D) Boxes for Ceiling Paddle Fan. Where a box is used as the sole support for a ceiling paddl . . . |
| |
320.17 Through or Parallel to Framing Members |
The text was revised to read:
AC cable installed through or parallel to framing members must be protected against physical damage f . . . |
| |
320.30 Securing and Supporting |
The text was revised to read:
(B) Unsupported. AC cable can be unsupported where the cable is:
(1) Fished between concealed acces . . . |
| |
334.10 Uses Permitted |
This subsection was completely revised to read:
Type NM and NMC cables can be used in any of the following occupancies:
(1) One and Two-Fa . . . |
| |
334.12 Uses Not Permitted |
The following text was added.
(A) Types NM, NMC, and NMS. Types NM, NMC, and NMS cables shall not be used as open runs in dropped o . . . |
| |
334.17 Through or Parallel to Framing Members |
The text was revised to read:
NM cable installed through or parallel to framing members must be protected against physical damage from penet . . . |
| |
338.10 Uses Permitted |
The text was revised to read:
(B) Branch Circuits or Feeders
(4) Installation Methods for Branch Circuits and Feeders.
(a) Interior Inst . . . |
| |
342.30 Securing and Supporting |
This subsection was revised to read:
(B) Supports
(3) Vertical Risers. Exposed vertical risers for industrial machinery . . . |
| |
354.6 Listing Requirement |
This new section reads:
NUCC and its associated fittings must be listed for the purpose. Figure 354–1 Intent: . . . |
| |
362.10 Uses Permitted |
A new exception was added and it reads:
(2) In buildings exceeding three floors. ENT must be installed concealed in walls, floors, . . . |
| |
362.10 Uses Permitted |
An exception was added and it reads:
(5) Above Suspended Ceiling. ENT can be installed above a suspended ceiling if the suspended ceiling . . . |
| |
376.23 Wireway Sizing |
This section was revised to read:
(A) Bending Radius. Where conductors are bent within a wireway, the wireway must be sized to mee . . . |
| |
376.23 Wireway Sizing |
This section was revised to read:
(B) Wireway Used as Pull Box. Where insulated conductors 4 AWG or larger are pulled thro . . . |
| |
392.3 Uses Permitted |
This section was revised to read:
Cable trays can be used as a support system for services, feeders, branch circuits, communication . . . |
| |
392.6 Installation |
This section was revised to read:
(J) Raceways, Cables, and Boxes Supported from Cable Trays. In industrial facilities where condi . . . |
| |
400.7 Uses Permitted |
The word “stationary” was replaced with “utilization.” The subsection was revised to read:
(A) Uses Permitted.
|
| |
400.8 Uses Not Permitted |
This subsection was revised to read:
Unless specifically permitted in 400.7, flexible cords and cables cannot be used for the following:
( . . . |
| |
404.8 Accessibility and Grouping |
The text to this section was revised to read:
(B) Voltage Between Adjacent Devices. Snap switches shall not be grouped or ganged i . . . |
| |
404.9 Provisions for Grounding Switch Faceplates |
The text to this subsection was revised to read:
(B) Grounding. Snap switches, including dimmer and similar control switche . . . |
| |
404.14 Rating and Use of Switches (including Dimmers) |
This new subsection reads:
(E) Dimmer. General use dimmer switches must only be used to control permanently installed incandescen . . . |
| |
406.8 Receptacles in Damp or Wet Locations |
Parts of this section were revised to read:
(B) Wet Locations
(1) 15 and 20A Outdoor Receptacles. 15 and 20A, 125 and 250V rece . . . |
| |
406.8 Receptacles in Damp or Wet Locations |
Parts of this section were revised to read:
(B) Wet Locations
(2) Other Receptacles. All other receptacles installed in a wet . . . |
| |
408.21 Grounded Conductor Terminations |
Intent: This new section should ensure that grounded (neutral) conductors terminate within the panelboard to an individual terminal. This has b . . . |
| |
408.21 Grounded Conductor Terminations |
Author’s Comment: If two grounded (neutral) conductors are connected to the same terminal, and someone removes one of the neutrals, . . . |
| |
430.52 Branch Circuit Short-Circuit Protection Device Rating |
Table 430-152, which contains the maximum rating or setting of motor branch-circuit short-circuit and ground-fault protective devices, was relocated t . . . |
| |
430.62 Feeder Protection Device Rating |
The first paragraph was revised to read:
(A) Motors Only. A feeder supplying a specific fixed motor load(s) and consisting of cond . . . |
| |
430.102 Disconnect Means Location |
This subsection and its exception were revised, and two Fine Print Notes were added. This subsection now reads:
(B) Motor Disconnect.
|
| |
440.14 Location |
A sentence was added to this section so that it now reads:
Disconnecting means must be located within sight (within 50 ft) from and readily . . . |
| |
445.13 Ampacity of Generator Conductors |
The first sentence of this section was revised:
The ampacity of the conductors from the generator terminals to the first distribution devic . . . |
| |
500.2 Definitions |
A new definition for Electrical and Electronic Equipment was added and it reads:
Electrical and Electronic Equipment. Materials, f . . . |
| |
500.8 Equipment |
Additional text was added to this subsection on the suitability of equipment and it reads:
(A) Approval for Class and Properties.
(1) Com . . . |
| |
501.5 Sealing and Drainage |
A new exception No. 2 was added to read:
(A) Conduit Seals, Class I, Division 1
(4) Boundary Seal. A sealing fitting must be inst . . . |
| |
505.21 Multiwire Branch Circuits |
A new section covering the requirements for multiwire branch circuits located in Zone-classified systems reads:
Multiwire Branch Circuits. . . . |
| |
511.3 Classifications of Locations |
This exception was revised to read:
(B) Classified Locations
(1) Up to 18 inches Above the Floor. For each floor, the entire are . . . |
| |
511.3 Classifications of Locations |
New subsection added for compressed natural gas and it reads:
(B) Classified Locations
(2) Within 18 in. of the Ceiling. Where C . . . |
| |
514.13 Disconnect for Maintenance and Service of Dispensing Equipment |
This section was revised to read:
Each dispensing device must be provided with a means to remove all external voltage sources, including fe . . . |
| |
517.13 Grounding of Receptacles and Fixed Electric Equipment in Patient Care Areas |
The section was completely revised to read as follows:
(B) Insulated Equipment Grounding Conductor. In areas used for patient care . . . |
| |
517.30 Essential Electrical Systems for Hospitals |
A new subsection was added and it reads:
(E) Receptacle Identification. The cover plates for receptacles, or receptacles supplied . . . |
| |
525.32 Grounding Conductor Continuity Assurance |
A new requirement was added to require testing of the equipment grounding conductor. This new section reads:
The continuity of the groundi . . . |
| |
527.3 Time Constraints |
The word “Christmas” was replaced with “holiday” so this section now reads:
(B) 90-Day Rule. Temporary ele . . . |
| |
527.4 General |
A new sentence was added to this subsection, which reads:
(J) Supports. Vegetation cannot be used for support of overhead spans of . . . |
| |
547.2 Definitions |
The definition for an Equipotential Plane was revised to read:
Equipotential Plane. An area where wire mesh or other conductive el . . . |
| |
547.5 Wiring Methods |
This section was revised to require equipment enclosures, boxes, conduit bodies, and fittings installed in agricultural buildings to comply with the f . . . |
| |
547.5 Wiring Methods |
The GFCI requirements for agricultural buildings were revised to read:
(G) Receptacles. All 15 and 20A, single-phase 125V general- . . . |
| |
550.25 Arc-Fault Circuit Interrupter Protection |
A new subsection was added and it reads:
(B) Bedrooms of Mobile Homes and Manufactured Homes. All branch circuits that supply 15 an . . . |
| |
555.2 Definitions |
A new definition for Electrical Datum Plane was added and it reads:
Electrical Datum Plane. The electrical datum plane is defined as . . . |
| |
555.17 Boat Receptacle Disconnecting Means |
The requirement for the boat disconnecting means was completely revised to read:
(B) Location. The disconnecting means for a boat . . . |
| |
555.19 Boat Receptacle |
New text was added and it reads:
(A) Boat Receptacles
(4) Ratings. Receptacles that provide shore power for boats must be rated n . . . |
| |
600.21 Ballasts, Transformers, and Electronic Power Supplies |
This subsection was revised to read:
(F) Suspended Ceilings. Ballasts, transformers, and electronic power supplies are permitted to . . . |
| |
604.6 Construction |
This section was completely revised to read:
(E) Support. Manufactured wiring systems must be supported in accordance with the re . . . |
| |
640.6 Mechanical Execution of Work/Cable Support |
The text to this section was revised to read:
Equipment and cabling must be installed in a neat and workmanlike manner. Cables installed e . . . |
| |
645.5 Supply Circuit and Interconnecting Cables |
This subsection was revised to read:
(D) Under Raised Floors
(2) Branch Circuit Supply Conductors. The branch-circuit supply cond . . . |
| |
Article 647 Sensitive Electronic Equipment Power or Balanced Power Systems |
A new Article covering the wiring requirements for “Sensitive Electronic Equipment Power or Balanced Power Systems” was added to the 2002 . . . |
| |
680.8 Overhead Conductor Clearances |
A new subsection was added, which reads:
(B) Communications Systems. Communication cables such as telephone, radio, and CATV cabl . . . |
| |
680.8 Overhead Conductor Clearances |
A new subsection was added, which reads:
(C) Network-Powered Broadband Communications Systems. Overhead network-powered broadband . . . |
| |
680.12 Maintenance Disconnecting Means |
The word “maintenance” was added to the heading and the text was revised to read:
One or more means to disconnect all . . . |
| |
680.22 Area Lighting, Receptacles, and Equipment |
A new item (4) was added and it reads:
(A) Receptacles
(4) Restricted Space. One 15 or 20A, single-phase, 125V receptacle can be . . . |
| |
680.22 Area Lighting, Receptacles, and Equipment |
This subsection was revised to read:
(A) Receptacles
(5) GFCI Protection. All 125V receptacles located within 20 ft. of the insid . . . |
| |
680.26 Bonding |
This section was revised to read:
(B) Bonding Together
(1) Metallic Parts of Pool Structure. All metallic parts of the water stru . . . |
| |
690.14 Additional Provisions |
A new subsection was added and it reads:
(C) Requirements for Disconnecting Means. Means must be provided to disconnect all conduct . . . |
| |
690.56 Identification of Power Sources |
A new section was added to Article 690 to cover the identification requirements for photovoltaic power systems supplying buildings, or structures or b . . . |
| |
700.12 General Requirements |
A new subsection was added and it reads:
(B) Generator Set
(6) Disconnect. Where an outdoor-housed generator for emergency circui . . . |
| |
701.11 Legally Required Standby Systems |
This subsection was revised to read:
(E) Connection Ahead of Service Disconnecting Means. Where acceptable to the Authority Having . . . |
| |
702.1 Scope |
The second paragraph was revised to read:
The systems covered by this Article consist of those that are permanently installed, including pr . . . |
| |
702.10 Portable Generator Grounding |
A new section was added for grounding portable generators, which reads:
(A) Separately Derived Systems. If the transfer switch for . . . |
| |
702.10 Portable Generator Grounding |
A new section was added for grounding portable generators, which reads:
(B) Nonseparately Derived System. If the transfer switch fo . . . |
| |
725.3 Locations of Other Articles |
The following requirement was added:
(B) Spread of Fire or Products of Combustion. The accessible portion of abandoned Class 2, Cla . . . |
| |
725.6 Mechanical Execution of Work |
The text to this section was revised to read:
Class 1, Class 2, and Class 3 circuits must be installed in a neat and workmanlike manner. Ca . . . |
| |
800.6 Mechanical Execution of Work |
The text to this section was revised to read:
Communications circuits must be installed in a neat and workmanlike manner. Cables installed . . . |
| |
800.40 Cable and Primary Protector Grounding |
New text was added to improve the grounding of Communications systems, it now reads:
The metallic member(s) of the cable sheath, where requi . . . |
| |
800.52 Locations and Other Articles |
The text to this subsection was revised to read:
(B) Spread of Fire or Products of Combustion. Installations in hollow spaces, ver . . . |
| |
810.21 Grounding Conductors – Receiving Stations |
The text to this subsection was revised to read:(F) Electrode. The grounding conductor as required by 810.14 and 20 must be connected . . . |
| |
820.33 Grounding of Outer Conductive Shield of a Coaxial Cable |
The text to this section was revised to read:
The outer conductive shield of the coaxial cable must be grounded at the building premises as . . . |
| |
820.40 CATV Cable Grounding |
New text was added to improve the grounding of CATV systems, it now reads:
Where required by 820.33, the shield of the coaxial cable shall b . . . |
| |
830.40 Cable, Network Interface Unit, and Primary Protector Grounding |
New text was added to improve the grounding of Network-Powered Broadband Communications systems, it now reads:
Network interface units conta . . . |
| |
Chapter 9, Table 4 Dimensions and Percent Area of Conduit and Tubing |
A 60 percent fill column was added for use with wire fill calculations for conduit or tubing nipples.
Intent: Note 4 to Table 1 of Chapter 9 . . . |
| |
Annex C – Conduit and Tubing Fill Tables for Conductors and Fixture Wires |
A table of contents was added for this table:
Table Page
C1 ― Electrical Metalli . . . |
| |
320.30 Secured and Supported |
Part II. Installation
This section was reorganized with editorial changes to add clarity and uniform interpretation. New subsection (A) General, . . . |
| |
320.80 Conductor Ampacities |
Changes clarify when the 90°C conductor insulation ampacity as listed in Table 310.16, can be used for conductor ampacity adjustment or correction, . . . |
| |
330.30 Secured and Supported |
Part III. Construction Specifications
This section was reorganized with editorial changes to add clarity and uniform interpretation. New subsect . . . |
| |
330.108 Equipment Grounding (Bonding) |
Section rewritten to clarify when Type MC cable is permitted to serve as an equipment grounding (bonding) path.
Where MC cable is us . . . |
| |
334.15 Exposed |
Part II. Installation
New rule permits NM cable in an unfinished basement to be installed into a raceway when coming down a wall, but the cable . . . |
| |
334.30 Secured or Supported |
New paragraph clarifies that NM cables installed within a raceway [334.15(C)] isn’t required to be secured within the raceway.
Type . . . |
| |
334.80 Ampacity |
A new paragraph requires conductors to have their ampacity adjusted, when more than one NM cable is bundled together as they pass through a fire- o . . . |
| |
348.30 Secured and Supported |
Part II. Installation
Revisions to Exception No. 2 relax the requirements for securing flexible metal conduit at terminations where flexibility . . . |
| |
376.23 Wireway Sizing |
Part II. Installation
Revisions to this rule should clear up the issue regarding the sizing of metal wireways as it relates to conductor bending . . . |
| |
400.5 Ampacity of Flexible Cords |
New rule requires conductor ampacity correction when flexible cords are used in an ambient temperature above 86°F.
Tables 400.5(A) and . . . |
| |
404.9 Switch Cover Plates |
Exception revised to permit metal switch cover plates at an outlet box where a grounding (bonding) means doesn’t exist, but only where the circuit . . . |
| |
406.4 Receptacle Mounting |
Text added to recognize the generally accepted practice, that receptacles mounted in boxes supported by a pendant flexible cord is permitted.
. . . |
| |
406.8 Receptacles in Damp or Wet Locations |
The word “outdoors” was deleted from this rule. The effect? All 15 and 20A 125V and 250V receptacles installed in a wet location (indoor or outdoor . . . |
| |
406.8 Receptacles in Damp or Wet Locations |
Revised wording clarifies where a receptacle isn’t permitted in a bathroom.
(C) Bathtub and Shower Space. Receptacles must n . . . |
| |
408.4 Circuit Directory or Circuit Identification |
Part I. General
This section on circuit identification was rewritten to improve safety by ensuring that workers don’t have to guess which breake . . . |
| |
408.7 Unused Openings |
New section specifies that unused openings for circuit breakers and switches must be closed in a manner approved by the authority having jurisdicti . . . |
| |
410.110. Listing of Decorative Lighting |
XVI. Decorative Lighting and Similar Accessories
Decorative lighting is now required to be listed for the purpose.
Decor . . . |
| |
410.1 Scope |
Part I. General
The scope of Article 410 has been expanded to include decorative lighting products, lighting accessories for temporary seasonal . . . |
| |
410.4 Luminaires in Specific Locations |
Part II. Luminaire Locations
The text was modified to clarify the types of luminaires not permitted within 3 ft horizontally and 8 ft vertically . . . |
| |
410.4 Luminaires in Specific Locations |
New subsection added to clarify when a lamp shield for mechanical protection is required for mercury vapor or metal halide lamps.
|
| |
410.14 Connection of Electric-Discharge Luminaires |
Part III. Luminaire Outlet Boxes and Covers
Additional text clarifies that the branch-circuit wiring must be accessible when electric-discharge . . . |
| |
410.30 Cord-Connected Luminaires |
Part VI. Wiring of Luminaires
Additional text clarifies that flexible cords with manufactured wiring system connectors (Relox®) can be used for . . . |
| |
410.73 General |
Part XIII. Electric-Discharge Lighting (1,000V or Less)
New rule specifies when luminaires with metal halide lamp are to be provided with a meth . . . |
| |
422.13 Storage Water Heaters |
Part II. Branch-Circuit Requirements
Text was revised to specify that a fixed storage water heater of 120 gallons or less is to be considered a . . . |
| |
422.16 Flexible Cords |
New rule allows range hoods to be cord-and-plug connected, if they comply with new stringent requirements.
(B) Specific Appliances.< . . . |
| |
424.3 Branch Circuits |
Part I. General
Editorial change to clarify that fixed electric space-heating equipment is a continuous load for branch circuit conductor sizing . . . |
| |
430.32 Overload Sizing – Continuous-Duty Motors |
Part III. Overload Protection
Text revised to clarify that overload protection is required for continuous duty motors rated more than 1 hp, but . . . |
| |
445.18 Disconnecting Means |
Change permits a single generator to have multiple disconnecting means to allow flexibility and to provide a safer environment when maintenance is . . . |
| |
501.15 Sealing and Drainage |
Part II. Wiring
Text revisions clarify that when a conduit leaves a Class I, Division 2 location to an unclassified location, the required bound . . . |
| |
511.3 Classification of Hazardous Areas |
This section was reorganized so that text related to unclassified locations is now located in 511.3(A) and text related to classified locations is . . . |
| |
511.3 Classification of Hazardous Areas - Continued |
(6) Flammable Liquids Having Flash Points Below 100 degrees F. Areas where flammable liquids having a flash point below 100°F, such as gasoline . . . |
| |
513.12 GFCI Protected Receptacles |
New section requires GFCI protection for 15 and 20A, 125V receptacles where aircraft might undergo service, repairs, or alterations.
|
| |
514.8 Underground Wiring |
Note added to Table 514.3 to identify the hazardous (classified) area around fuel dispensing facilities on floating docks.
Text revised to clari . . . |
| |
517.18 General Care Areas |
Part II. Wiring and Protection
Additional text expands the required use of tamper resistant receptacles or tamper resistant covers in pediatric . . . |
| |
525.23 GFCI Protection |
This section was extensively rewritten to clarify where GFCI protection is required, where GFCI protection is not required, and where GFCI protecti . . . |
| |
547.5 Wiring Methods |
The rules for GFCI protection of receptacles were relocated from 547.10(B) to 547.5(G). In addition, general-purpose receptacles located in dirt co . . . |
| |
547.10 Equipotential Planes and Bonding of Equipotential Planes |
Section revised to clarify when an equipotential plane is required in livestock buildings. Previous Codes required an equipotential plane where met . . . |
| |
551.71 Type of Receptacles Required |
VII. Recreational Vehicle Parks
Text revised to increase the number of 50A, 125/250V receptacle recreational vehicle sites from 5 percent to 20 . . . |
| |
555.22 Repair Facilities |
Electrical wiring and equipment at facilities used to repair marine craft must now comply with the installation requirements of Article 511 Commerc . . . |
| |
590.4 General |
Revised text clarifies that Type NM cable used for temporary feeder installations isn’t limited by building height, construction type, or concealme . . . |
| |
590.4 General |
New exception recognizes that in many cases the only available support for holiday branch circuit lighting is live vegetation (trees).
< . . . |
| |
604.6 Construction |
The title and text of this section were changed to require manufactured wiring systems to be secured, as well as supported, in accordance with the . . . |
| |
680.26 Equipotential Bonding |
Equipotential grid now required in or under the permanently installed pool, outdoor spa, and outdoor hot tub deck to help mask stray voltage from u . . . |
| |
680.32 GFCI Protected Receptacles |
Part III. Storable Swimming Pool
Additional text requires GFCI protection for receptacles located within 20 ft of a storable pool.
|
| |
680.34 Receptacle Locations |
Additional text to specify the minimum distance a receptacle is permitted from a storable pool.
Receptacles must not be located less . . . |
| |
680.58 GFCI Protected Receptacles |
Part V. Fountains
The GFCI protection requirement for 15 or 20A receptacles within 20 ft of fountains was relocated to this section from 680.22( . . . |
| |
680.12 Maintenance Disconnecting Means |
This rule was revised to clarify that the permanently installed pool, storable pool, outdoor spa and hot tub, or fountain equipment maintenance dis . . . |
| |
680.22 Area Lighting, Receptacles, and Equipment |
Text added to clarify that GFCI protection is only required for 15 and 20A, 125V receptacles located within 20 ft of the inside walls of a permanen . . . |
| |
680.26 Equipotential Bonding |
Change requires an equipotential bonding grid be installed to reduce voltage gradients in and around permanently installed pools, outdoor spas, and . . . |
| |
695.6 Power Wiring |
The text was revised to alert the Code user that the branch circuit conductors for a fire pump motor are sized in accordance with 430.22. In . . . |
| |
725.3 Other Articles |
Part I. General
Text revised to specify that accessible portions of abandoned Class 2, Class 3, and PLTC cables must be removed.
. . . |
| |
725.3 Other Articles |
Changes clarify the types of cables and raceways permitted in ducts, plenums, and other space used for environmental air.
(C) Ducts, . . . |
| |
725.61 Applications of Class 2 and Class 3 Cables |
New sentence identifies the type of nonmetallic raceway containing Class 2 or Class 3 cables that is permitted in “other spaces used for environmen . . . |
| |
725.82 Listing and Marking of Class 2 and Class 3 Cables |
Part VI. Listing Requirements
New subsections added to recognize the use of raceways designed for Class 2 and Class 3 cables.
. . . |
| |
760.3 Other Articles |
Part I. General
Text revised to specify that accessible portions of abandoned fire alarm cables must be removed.
Only those sectio . . . |
| |
760.21 GFCI and AFCI Protection |
Part II. Nonpower-Limited Fire Alarm (NPLFA) Circuits
New rule prohibits AFCI protection of the 120V circuit that supplies power for a nonpower- . . . |
| |
770.3 Other Articles |
Part I. General
Text revised to specify that the accessible portion of abandoned optical fiber cables must be removed.
(A) Spread . . . |
| |
800.3 Other Articles |
Part I. General
Text revised to specify that the accessible portion of communications cables must be removed.
(C) Spread of Fire . . . |
| |
800.100 Cable and Primary Protector Grounding |
Part IV. Grounding Methods
New FPN alerts the Code user that limiting the length of the grounding conductor for the primary protector sho . . . |
| |
810.21 Grounding Conductors |
Part II. Receiving Equipment − Antenna Systems
New subsection clarifies the type of grounding electrode termination fitting that is suitab . . . |
| |
820.3 Other Articles |
Part I. General
Text revised to clarify that the accessible portion of abandoned coaxial cables must be removed.
(A) Spread of Fi . . . |
| |
820.100 Cable Grounding |
Part IV. Grounding Methods
New FPN alerts the Code user that limiting the length of the grounding conductor should reduce voltages that m . . . |
| |
820.182 CATV Raceways |
Part VI. Listing Requirements
New subsections added to recognize the use of raceways designed for coaxial cables.
(A) P . . . |
| |
830.1 Scope |
Part I. General
Article 830 contains the installation requirements for network-powered broadband communications circuits that provide voice, aud . . . |
| |
90.2 Scope of NEC |
New FPN identifies the type of organizations that may be exempt from the NEC requirements.
(B) What
Isn’t Covered. The
|
| |
Handhole Enclosure |
New definition “handhole enclosure” was added because the term will be used in the following:
- Enclosure not required for splices, 300. . . .
|
| |
Qualified Person |
FPN was added to the definition of ”qualified person” to give examples of the type of safety training required for a person to be considered qualif . . . |
| |
Separately Derived System |
The definition for a “separately derived system” was revised by eliminating the list of electric energy power sources that constitute a separately . . . |
| |
Supplementary Overcurrent Protective Device |
The new term “supplementary overcurrent protection device’ clarifies the difference between “supplementary overcurrent protective device” and “bran . . . |
| |
System Bonding Jumper |
A new term “system bonding jumper” was added for use with separately derived systems. Previously the term “main bonding jumper” was used to describ . . . |
| |
Device |
The definition of the term “device” was revised to clarify that electronic and electromechanical equipment used to control electric energy is consi . . . |
| |
Dwelling Unit |
The definition of a “dwelling unit” was revised to make it consistent with other NFPA standards, like NFPA 101, Life Safety Code, without im . . . |
| |
Solidly Grounded |
The term “solidly grounded” was contained in 230.95, but it was relocated to Article 100 because it’s used in at least eleven articles.
|
| |
Grounding Electrode |
A new term “grounding electrode” was added to Article 100 because it’s used in twenty-three articles from Article 250 through Article 830.
|
| |
Grounding Electrode Conductor |
The definition for “grounding electrode conductor” was reworded to clarify that the conductor that connects the building or structure disconnecting . . . |
| |
Guest Room |
The new term “guest room” was added because it’s used in Articles 210, 220, and 240. The definition matches the term found in NFPA 101, Life Saf . . . |
| |
110.16 Flash Protection Warning |
The term “meter socket enclosures” was added to the list of equipment on which field marking is required to warn qualified persons of potential ele . . . |
| |
110.26 Spaces About Electrical Equipment |
Part II. 600V, Nominal or Less
Revised text allows the area housing electrical equipment to be controlled by locks of any type, including a comb . . . |
| |
200.6 Means of Identifying Grounded Neutral Conductors |
The means of identification of grounded neutral conductors larger than 6 AWG was revised to allow gray as well as white markings at terminations.
|
| |
200.7 Use of White or Gray Color |
New sentence added to remove confusion and misinterpretation in the field on the requirements for reidentifying white conductors in cable assemblie . . . |
| |
210.52 Dwelling Unit Receptacle Outlets |
Part III. Required Outlets
New exception and diagram added to clarify that a countertop receptacle outlet isn’t required on a wall directly behi . . . |
| |
210.52 Dwelling Unit Receptacle Outlets |
A new exception permits the required bathroom receptacle outlet to be mounted on the basin cabinet. This exception provides an alternative location . . . |
| |
210.52 Dwelling Unit Receptacle Outlets |
New rule requires at least one outdoor receptacle outlet for each grade level dwelling unit with an individual entrance. This will help remove the . . . |
| |
210.63 Heating, Air-Conditioning, and Refrigeration Equipment (HACR) |
New exception clarifies that a receptacle outlet isn’t required within 25 ft of evaporative coolers at one- and two-family dwellings.
A . . . |
| |
210.70 Lighting Outlets Required |
Revised text and two new exceptions clarify that lighting outlets in guest rooms or guest suites provided with permanent provisions for cooking mus . . . |
| |
210.4 Multiwire Branch Circuits |
Part I. General Provisions
New FPN alerts the Code user to ensure that the continuity of the grounded neutral conductor of a multiwire ci . . . |
| |
210.5 Identification for Branch Circuits |
The requirement for branch-circuit identification was relocated from 210.4(D) to 210.5(C) and the text expanded to require circuit identification f . . . |
| |
210.7 Branch-Circuit Requirements |
Changing the word “receptacle” to “device or equipment” was intended to bring 210.7 in line with other NEC sections to create more consisten . . . |
| |
210.8 GFCI Protection |
Revised text to require all 15 and 20A, 125V receptacles within 6 ft of the dwelling unit laundry or utility sink to be GFCI protected. This is bec . . . |
| |
210.8 GFCI Protection |
The GFCI protection requirement for commercial kitchens was clarified by adding a definition of a kitchen. New requirement expands the GFCI protect . . . |
| |
210.12 Arc-Fault Circuit-Interrupter Protection |
Revised text to require, after January 1, 2008 that all dwelling unit bedroom branch-circuit AFCI protection devices must be listed as a “Combinati . . . |
| |
215.2 Minimum Rating and Size |
New sentence requires the feeder grounded neutral conductor to be sized so that it has adequate fault-current capacity, in the event a short circui . . . |
| |
215.12 Identification for Feeders. |
New section contains the identification requirements for feeder conductors so that they are similar with the branch-circuit identification requirem . . . |
| |
225.17 Masts as Supports |
Part I General Requirements
Overhead feeder and branch-circuit final spans are sometimes attached to the building through the use of masts. This . . . |
| |
230.71 Number of Disconnects |
Part VI. Service Equipment – Disconnecting Means
The disconnecting means for transient voltage surge suppressors (TVSS) are not counted as a ser . . . |
| |
230.82 Equipment on the Supply Side |
New subsection permits the installation of a meter disconnect switch ahead of the service disconnect.
Electrical equipment must not be . . . |
| |
240.20 Ungrounded Conductors |
Part II. Location
The word “approved” was replaced with “identified for the purpose.” The result… nails, screws, or wire are no longer permitted . . . |
| |
240.21 Overcurrent Protection Location in Circuit |
New sentence confirms that the “next size up” protection device rule of 240.4(B) doesn’t apply to feeder tap conductors.
(B) Feeder Ta . . . |
| |
240.21 Overcurrent Protection Location in Circuit |
New text clarifies that an individual transformer can supply more than a single load and the “next size up” protection of conductor rule contained . . . |
| |
240.24 Location of Overcurrent Protection Devices |
New text specifies the maximum height that an overcurrent device can be installed, and still be considered “readily accessible.” New text coordinat . . . |
| |
240.24 Location of Overcurrent Protection Devices in Premises |
Overcurrent devices must not be located in bathrooms of guest suites, as well as guest rooms of hotels and motels.
(E) Not in Bathroom . . . |
| |
250.34 Generators – Portable and Vehicle-Mounted |
Revision clarifies when portable and vehicle-mounted generators are not required to be grounded to a grounding electrode.
(A) Portable . . . |
| |
250.50 Grounding Electrode System |
Part III. Grounding Electrode System and Grounding Electrode Conductor
The words “if available” have been replaced with “are present.” The effec . . . |
| |
250.52 Grounding Electrodes |
The language in the 2002 NEC was vague and subject to wide interpretation as it described when the metal frame of a building or structure co . . . |
| |
250.52 Grounding Electrodes |
New FPN reminds the Code user that gas piping that is likely to become energized must be ”bonded” in accordance with the 250.104(B).
( . . . |
| |
250.54 Supplementary Electrodes |
Revision to help the Code user understand that an equipment grounding (bonding) conductor is intentionally constructed to assist in clearing . . . |
| |
250.64 Grounding Electrode Conductor Installation |
New text permits the grounding electrode conductors and bonding jumpers to terminate to a busbar as an alternative method.
(C) Continu . . . |
| |
250.64 Grounding Electrode Conductor Installation |
The revisions clarify when the raceway for the grounding electrode conductor must be bonded at each raceway/cable termination between the service e . . . |
| |
250.100 Bonding – Hazardous (Classified) Locations |
Part V. Bonding
The text was revised to clarify the bonding requirements of metal raceways that enter a hazardous (classified) location. An addi . . . |
| |
250.104 Bonding of Piping Systems and Exposed Structural Metal |
The words “that may become energized” were replaced with “is likely to become energized” to editorially clarify when the metal piping system, inclu . . . |
| |
250.104 Bonding of Piping Systems and Exposed Structural Metal |
The words “that may become energized” were replaced with “is likely to become energized” to editorially clarify when structural metal must be bonde . . . |
| |
250.2 Definitions |
Part I. General
Additional text helps the Code user understand that the purpose of the effective ground fault current path is to help cle . . . |
| |
250.104 Bonding of Piping Systems and Exposed Structural Metal |
The structural metal member bonding requirements that were located in 250.30(A)(3)(d) and 250.104(A)(1) were combined and relocated to 250.104(D) t . . . |
| |
250.118 Types of Equipment Grounding (Bonding) Conductors |
Part VI. Equipment Grounding (Bonding) and Equipment Grounding (Bonding) Conductors
New text specifies when an equipment (bonding) conductor is . . . |
| |
250.119 Identification of Equipment Grounding (Bonding) Conductor |
New sentence to make it clear that conductors that have an outer finish that is green or green with one or more yellow stripes cannot be used for u . . . |
| |
250.122 Sizing Equipment Grounding (Bonding) Conductor |
New rule describes how the equipment grounding (bonding) conductors for feeder taps are to be sized.
(G) Feeder Tap Conductors.
|
| |
250.140 Grounding (Bonding) – Ranges, Ovens, and Clothes Dryers |
Part VII. Methods of Equipment Grounding (Bonding)
The section on grounding (bonding) of ranges, ovens, and clothes dryers was rewritten to make . . . |
| |
250.146 Receptacle Grounding (Bonding) |
New sentence clarifies how to ensure direct metal-to-metal contact between the metal mounting yoke of a receptacle and the metal box when a bonding . . . |
| |
250.4 General Requirements for Grounding and Bonding |
Change clarifies that swift operation of an overcurrent protection device in the presence of a ground-fault depends upon the existence of an effect . . . |
| |
250.8 Termination of Grounding and Bonding Conductors |
Revised text clarifies that terminals for grounding conductors or bonding jumpers must be attached to enclosures in a suitable method to ensure an . . . |
| |
250.24 Grounding and Bonding at Service Equipment |
Part II. System Grounding (Bonding)
Editorial - the term “neutral conductor” was replaced with “grounded conductor.” According to the IEEE Dicti . . . |
| |
250.28 Main Bonding Jumper and System Bonding Jumper |
To avoid confusion when dealing with bonding jumpers, the requirement for the system bonding jumper was added to this section.
System . . . |
| |
250.30 Grounding and Bonding of Separately Derived AC Systems |
Text clarifies the method of sizing equipment bonding jumpers when the separately derived system conductors are run in parallel. And the text relat . . . |
| |
250.32 Buildings or Structures Supplied by a Feeder or Branch Circuit. |
A new sentence was added to the exception to clarify that a grounding electrode isn’t required at a remote building or structure supplied by a sing . . . |
| |
300.4 Protection Against Physical Damage |
Part I. General Requirements
Text expands the requirements to furring strips when 11/4” clearance is required for cables run parallel to framing . . . |
| |
300.6 Protection Against Corrosion and Deterioration |
This section was rewritten to ensure that raceways and fittings are properly protected against corrosion and deterioration. In addition, this secti . . . |
| |
300.11 Securing and Supporting |
Wording added to clarify that independent support wires for electrical equipment and wiring can be attached to the ceiling grid.
(A) S . . . |
| |
300.18 Inserting Conductors in Raceways |
New exception clarifies when raceways aren’t required to be complete before the installation of circuit conductors.
(A) Complete Runs. . . . |
| |
310.8 Locations |
This subsection was reorganized in a list format to clarify the requirements for protecting conductors against ultraviolet (UV) rays from direct su . . . |
| |
310.10 Insulation Temperature Limitation |
New FPN alerts the designer to consider elevated ambient temperatures when raceways are installed outdoors in direct sunlight in close proximity to . . . |
| |
310.15 Conductor Ampacity |
Text added to clarify how each current-carrying conductor of a parallel conductor set is to be treated when applying the ampacity adjustment factor . . . |
| |
312.4 Repairing Gaps in Plaster, Drywall, or Plasterboard |
New rule added to require the sealing of gaps or open spaces around cabinets or cutout boxes having a flush-type cover, as is required around outle . . . |
| |
314.1 Scope |
Part I. Scope and General
The scope of Article 314 was expanded to include the requirements for handhole enclosures. See 314.30 for details. . . . |
| |
314.16 Number of 6 AWG and Smaller Conductors in Boxes and Conduit Bodies |
Part II. Installation
New sentence requires conductor volume calculations to be increased in size when conductors are looped or run unbroken thr . . . |
| |
314.20 Boxes Recessed in Walls or Ceilings |
Additional text clarifies the setback requirements for plaster rings, extension rings, or listed extender, as well as boxes from combustible surfac . . . |
| |
314.21 Repairing Gaps Around Boxes |
Additional text clarifies when gaps around boxes must be repaired.
Gaps around boxes recessed in plaster, drywall, or plasterboard h . . . |
| |
314.27 Outlet Boxes |
The support requirements for a ceiling paddle fan previously contained in 422.18 were relocated to 314.27(D). This makes it unnecessary to use two . . . |
| |
314.30 Handhole Enclosures |
New section contains the requirements for handhole enclosures.
Handhole enclosures must be designed and installed to withstand all l . . . |
| |
250.62 Grounding Electrode Conductor—Material. |
The grounding electrode conductor, or its jumpers, can be solid or stranded, insulated or bare, and it must be copper, except aluminum is permitted if . . . |
| |
250.64 Grounding Electrode Conductor Installation. |
(A) Aluminum Grounding Electrode Conductor. Aluminum grounding electrode conductors cannot be in contact with earth, masonry, or subjected to . . . |
| |
250.66 Grounding Electrode Conductor—Size. |
Except for a ground rod electrode [250.66(A)], a concrete-encased electrode [250.66(B)], or a ground ring electrode [250.66(C)], the grounding electro . . . |
| |
250.68 Grounding Electrode Conductor Termination. |
(A) Attachment Fitting. The grounding electrode attachment fitting must be accessible.
Exception 1: The grounding electrode attachment . . . |
| |
250.70 Grounding Electrode Conductor Termination Fitting. |
The grounding electrode conductor must terminate to the grounding electrode by exothermic welding, listed lugs, listed pressure connectors, listed cla . . . |
| |
250.50 Grounding Electrode System. |
All grounding electrodes as described in 250.52(A)(1) through (A)(6) that are present at each building or structure must be bonded together to form th . . . |
| |
250.52 Grounding (Earthing) Electrodes. |
(A) Electrodes Permitted for Grounding.
(1) Underground Metal Water Pipe Electrode. Underground metal water pipe in direct contact . . . |
| |
250.52 Grounding (Earthing) Electrodes Continued |
(6) Ground Plate Electrode. A buried iron or steel plate with not less than 1⁄4 in. of thickness, or a nonferrous (copper) metal plate no . . . |
| |
250.53 Installation of Grounding Electrode System. |
(A) Ground Rod Electrodes. Where practicable, ground rods must be embedded below permanent moisture level and must be free from nonconductive . . . |
| |
250.54 Supplementary Electrodes. |
A supplementary electrode is an electrode that is not required by the NEC. This electrode is not required to be bonded to the building or structure gr . . . |
| |
250.56 Resistance of Ground Rod Electrode. |
When the resistance of a single ground rod is over 25 ohms, an additional electrode is required to augment the ground rod electrode, and it must be in . . . |
| |
250.58 Common Grounding (Earthing) Electrode. |
Where a building or structure is supplied with multiple services or feeders as permitted by 225.30 and 230.2, the same electrode must be used to groun . . . |
| |
250.60 Lightning Protection System Grounding (Earthing) Electrode. |
The grounding electrode for a lightning protection system cannot be used for the building or structure grounding electrode system as required by 250.5 . . . |
| |
250.80 Service Enclosures. |
Metal raceways and enclosures containing service conductors must be grounded (bonded) to an effective ground-fault current path [250.4(A)(5)].
E . . . |
| |
250.86 Other Enclosures. |
Metal raceways and enclosures containing electrical conductors that operate at over 50V [250.112(I)] must be grounded (bonded) to an effective ground- . . . |
| |
250.92 Service Bonding. |
(A) Equipment and Raceways. The following metal parts must be service bonded to an effective ground-fault current path in accordance with 250 . . . |
| |
250.106 Lightning Protection System. |
Where a lightning protection system is installed, the lightning protection system must be bonded to the building or structure grounding electrode syst . . . |
| |
250.92 Service Bonding Continued |
(2) Threaded Fittings or Entries. Raceways containing service conductors are considered bonded to an effective ground-fault current path by thr . . . |
| |
250.94 Grounding (Bonding) of Communications Systems. |
An accessible bonding point must be provided at service equipment or the disconnecting means of separate buildings or structures for communications sy . . . |
| |
250.96 Bonding Other Enclosures. |
(A) Maintaining Effective Ground-Fault Current Path. All metal parts intended to serve as the effective ground-fault current path, such as ra . . . |
| |
250.97 Bonding 277V/480V. |
Metal raceways or cables, containing 277V or 480V circuits, terminating at ringed knockouts must be bonded to the metal enclosure with a bonding jumpe . . . |
| |
250.100 Bonding—Hazardous (Classified) Locations. |
Because of the explosive conditions associated with electrical installations in hazardous (classified) locations, electrical continuity of the effecti . . . |
| |
250.102 Bonding Jumper. |
(A) Bonding Material. Bonding jumpers must be of copper.
(B) Bonding Jumper Attachment. Bonding jumpers must terminate by exother . . . |
| |
250.104 Bonding of Piping Systems and Exposed Structural Metal. |
Author’s Comment: To remove dangerous voltage on metal parts from a ground fault, electrically conductive metal water piping systems, met . . . |
| |
250.104 Bonding of Piping Systems and Exposed Structural Metal Continued |
(D) Separately Derived Systems. Metal water pipe systems and structural metal that forms a building frame must be bonded in accordance with ( . . . |
| |
250.118 Types of Equipment Grounding (Bonding) Conductors. |
The equipment grounding (bonding) conductor, which serves as the effective ground-fault current path to the source, must be one or a combination of th . . . |
| |
250.118 Types of Equipment Grounding (Bonding) Conductors Continued |
(9) The copper metal sheath of Type MI cable.
(10) Type MC cable where listed and identified for grounding as follows:
a. Interlocked Type MC . . . |
| |
250.119 Identification of Equipment Grounding (Bonding) Conductor. |
Unless required to be insulated, equipment grounding (bonding) conductors can be bare.
Author’s Comment: Equipment grounding (bonding) . . . |
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250.122 Sizing Equipment Grounding (Bonding) Conductor. |
(A) General. The equipment grounding (bonding) conductor must be sized in accordance with Table 250.122, based on the ampere rating of the ci . . . |
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250.122 Sizing Equipment Grounding (Bonding) Conductor Continued |
(B) Increased in Size. When ungrounded circuit conductors are increased in size for any reason, the equipment grounding (bonding) conductor m . . . |
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250.126 Identification of Wiring Device Terminals. |
The terminal for the equipment grounding (bonding) conductor must be a:
(1) Green screw, hexagonal head, and not readily removable. Figure 250 . . . |
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250.130 Equipment Grounding (Bonding) Conductor Connections. |
(A) For Grounded Systems. The service disconnecting means supplied by a grounded utility system must have the grounded neutral service conduc . . . |
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250.134 Grounding (Bonding)—Fixed Equipment. |
Metal parts of fixed electrical equipment, raceways, and enclosures must be grounded (bonded) to an effective ground-fault current path in accordance . . . |
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250.140 Grounding (Bonding)—Ranges, Ovens, and Clothes Dryers. |
The frames of electric ranges, wall-mounted ovens, counter-mounted cooking units, clothes dryers, and outlet boxes that are part of the circuit for th . . . |
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250.142 Use of Grounded Neutral Conductor for Equipment Grounding (Bonding). |
Author’s Comment: To remove dangerous voltage on metal parts from a ground fault, the metal parts of electrical raceways, cables, enclosu . . . |
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250.146 Connecting Receptacle Grounding Terminal to Box |
Receptacles must have their grounding contacts connected to an effective ground-fault current path by bonding the receptacle’s grounding terminal to a . . . |
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250.146 Connecting Receptacle Grounding Terminal to Box Continued |
(C) Floor Boxes. Listed floor boxes are permitted to establish the bonding path between the device yoke and a grounded (bonded) outlet box.
. . . |
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250.148 Continuity and Attachment of Equipment Grounding (Bonding) Conductors to Boxes. |
Equipment grounding (bonding) conductors associated with circuit conductors that are spliced or terminated on equipment within a metal outlet box, mus . . . |
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250.20 Systems Required to be Grounded and Bonded |
Alternating-current systems (power supplies) must be grounded and bonded as provided in (A), (B), (C), or (D).
Author’s Comment: System grounding, th . . . |
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250.32 Buildings or Structures Supplied by a Feeder or Branch Circuit. |
(A) Grounding Electrode. To provide a path to earth for lightning, each building or structure must have its disconnecting means [225.31] grou . . . |
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250.32 Buildings or Structures Supplied by a Feeder or Branch Circuit Continued |
The equipment grounding (bonding) conductor, if of the wire type, must be sized in accordance with 250.122, based on the rating of the feeder protecti . . . |
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250.34 Generators—Portable and Vehicle-Mounted |
(A) Portable Generators. The frame of a portable generator isn’t required to be grounded to the earth if: Figure 250–88
(1) The g . . . |
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250.36 High-Impedance Grounded Neutral Systems. |
To limit fault current to a very low value, high-impedance grounded neutral systems have a resistor installed between the system and the metal parts o . . . |
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250.20 Systems Required to be Grounded and Bonded Continued |
(D) Separately Derived Systems. Separately derived systems that are required to be grounded (bonded) by 250.20(A) or (B), must be grounded an . . . |
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250.24 Grounding and Bonding at Service Equipment. |
(A) Grounding. Services supplied from a utility transformer that is grounded to the earth must have the grounded neutral conductor grounded t . . . |
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250.24 Grounding and Bonding at Service Equipment Continued |
(C) Grounded Neutral Conductor Required. Because electric utilities aren’t required to provide an equipment grounding (bonding) conductor to . . . |
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250.24 Grounding and Bonding at Service Equipment Continued |
Author’s Comments:
• A ground-fault cannot be cleared to remove dangerous voltage on the metal parts, metal piping, and structural steel . . . |
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250.28 Main Bonding Jumper and System Bonding Jumper. |
(2) Parallel Grounded Neutral Conductor. Where service conductors are paralleled, a grounded neutral conductor must be installed in each racewa . . . |
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250.30 Grounding and Bonding of Separately Derived AC Systems. |
Author’s Comment: A separately derived system is a premises wiring system with no direct electrical connection to conductors originating . . . |
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250.30 Grounding and Bonding of Separately Derived AC Systems Continued |
The system bonding jumper can be installed at the separately derived system, the first system disconnecting means, or any point in between the separat . . . |
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250.30 Grounding and Bonding of Separately Derived AC Systems Continued |
To prevent objectionable current from flowing onto metal parts of electrical equipment, as well as metal piping and structural steel, the grounding el . . . |
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250.6 Objectionable Current Continued |
Fire Hazard. When objectionable current flows on metal parts, a fire could occur because of elevated temperature, which can ignite adjacent com . . . |
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250.8 Termination of Grounding and Bonding Conductors. |
The termination of equipment grounding and bonding conductors must be by exothermic welding, listed pressure connectors of the set screw or compressio . . . |
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250.2 Definitions. |
Author’s Comment: Why is grounding so difficult to understand? One reason is because many do not understand the definition of many import . . . |
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250.2 Definitions Continued |
Ground (Earth) [100]. Earth or a conductive body that is connected to earth. Figure 250–6
Grounded [100]. Connected to eart . . . |
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250.2 Definitions Continued |
Grounding (Earthing) Electrode [100]. A device that establishes an electrical connection to the earth. Figure 250–11
Autho . . . |
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250.4 General Requirements for Grounding and Bonding. |
(A) Solidly Grounded Systems.
(1) Grounding Electrical Systems to the Earth. High-voltage system windings are grounded to the earth . . . |
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250.4 General Requirements for Grounding and Bonding Continued |
(4) Bonding Conductive Materials to an Effective Ground-Fault Current Path. To remove dangerous voltage from ground faults, electrically conduc . . . |
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250.4 General Requirements for Grounding and Bonding Continued |
To understand how a ground rod is useless in reducing touch voltage to a safe level, let’s answer the following questions:
What is touch volta . . . |
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250.6 Objectionable Current. |
(A) Preventing Objectionable Current. To prevent a fire, electric shock, or improper operation of circuit-protection devices or sensitive equ . . . |
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250.6 Objectionable Current Continued |
Wiring Errors
Objectionable current will flow on metal parts when the grounded neutral conductor from one system is connected to a circuit . . . |
