This Electrical Part (Chapters 34 through 43) is produced and copyrighted by the National Fire Protection Association (NFPA) and is based on the 2020 National Electrical Code® (NEC®) (NFPA 70®-2020), copyright 2019, National Fire Protection Association, all rights reserved. Use of the Electrical Part is pursuant to license with the NFPA.
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ICC user note:
About this chapter: Chapter 34 contains broadly applicable requirements including provisions for the protection of the structural elements of a building, inspection of work, general installation and conductor identification. This chapter requires that all electrical system components be listed and labeled by an approved agency. The electrical provisions of this code are identical to the intent of the NEC provisions except that this code requires all electrical system components be listed and labeled. The code does not contain unique electrical requirements. A dwelling built to the code will have electrical systems identical to those required by the respective edition of the NEC. This code addresses only those electrical systems that are common to dwelling construction, and the NEC is referenced for any subject not addressed in the code.
Enclosures, other than surrounding fences or walls, of panelboards, meter sockets, enclosed switches, transfer switches, circuit breakers, pullout switches and motor controllers, rated not over 600 volts nominal and intended for such locations, shall be marked with an enclosure-type number as shown in Table E3404.4.
Table E3404.4 shall be used for selecting these enclosures for use in specific locations other than hazardous (classified) locations. The enclosures are not intended to protect against conditions such as condensation, icing, corrosion, or contamination that might occur within the enclosure or enter through the raceway or unsealed openings. (110.28)
TABLE E3404.4 (Table 110.28)
|PROVIDES A DEGREE OF PROTECTION AGAINST THE FOLLOWING ENVIRONMENTAL CONDITIONS||FOR OUTDOOR USE|
|Enclosure type number|
|Incidental contact with the enclosed equipment||X||X||X||X||X||X||X||X||X||X|
|Rain, snow and sleet||X||X||X||X||X||X||X||X||X||X|
|PROVIDES A DEGREE OF PROTECTION AGAINST THE FOLLOWING ENVIRONMENTAL CONDITIONS||FOR INDOOR USE|
|Enclosure type number|
|Incidental contact with the enclosed equipment||X||X||X||X||X||X||X||X||X||X|
|Falling liquids and light splashing||—||X||X||X||X||X||X||X||X||X|
|Circulating dust, lint, fibers and flyings||—||—||X||X||—||X||X||X||X||X|
|Settling airborne dust, lint, fibers and flyings||—||—||X||X||X||X||X||X||X||X|
|Hosedown and splashing water||—||—||X||X||—||X||X||—||—||—|
|Oil and coolant seepage||—||—||—||—||—||—||—||X||X||X|
|Oil or coolant spraying and splashing||—||—||—||—||—||—||—||—||—||X|
Note 1: The term "raintight" is typically used in conjunction with Enclosure Types 3, 3S, 3SX, 3X, 4, 4X, 6 and 6P. The term "rainproof" is typically used in conjunction with Enclosure Types 3R and 3RX. The term "watertight" is typically used in conjunction with Enclosure Types 4, 4X, 6 and 6P. The term "driptight" is typically used in conjunction with Enclosure Types 2, 5, 12, 12K and 13. The term "dusttight" is typically used in conjunction with Enclosure Types 3, 3S, 3SX, 3X, 5, 12, 12K and 13.
Note 2: Ingress protection (IP) ratings are found in ANSI/NEMA 60529, Degrees of Protection Provided by Enclosures. IP ratings are not a substitute for enclosure-type ratings.
Except as otherwise specified in Chapters 34 through 43, the dimension of the working space in the direction of access to panelboards and live parts of other equipment likely to require examination, adjustment, servicing or maintenance while energized shall be not less than 36 inches (914 mm) in depth. Distances shall be measured from the energized parts where such parts are exposed or from the enclosure front or opening where such parts are enclosed. In addition to the 36-inch dimension (914 mm), the work space shall not be less than 30 inches (762 mm) wide in front of the electrical equipment and not less than the width of such equipment. The work space shall be clear and shall extend from the floor or platform to a height of 6.5 feet (1981 mm) or the height of the equipment, whichever is greater. In all cases, the work space shall allow at least a 90-degree (1.57 rad) opening of equipment doors or hinged panels. Equipment or support structures, such as concrete pads, associated with the electrical installation located above or below the electrical equipment shall be permitted to extend not more than 6 inches (152 mm) beyond the front of the electrical equipment.
The indoor space equal to the width and depth of the panelboard and extending from the floor to a height of 6 feet (1829 mm) above the panelboard, or to the structural ceiling, whichever is lower, shall be dedicated to the electrical installation. Piping, ducts, leak protection apparatus and other equipment foreign to the electrical installation shall not be installed in such dedicated space. The area above the dedicated space shall be permitted to contain foreign systems, provided that protection is installed to avoid damage to the electrical equipment from condensation, leaks and breaks in such foreign systems (see Figure E3405.1).
Exception: Suspended ceilings with removable panels shall be permitted within the 6-foot (1829 mm) dedicated space.
|CONDUCTOR SIZE||NUMBER OF STRANDS|
|AWG or kcmil||mm2||Class B||Class C||Class B|
Conductors in raceways shall be continuous between outlets, boxes, and devices and shall be without splices or taps in the raceway.
Equipment grounding conductors, grounding electrode conductors, and bonding jumpers shall be connected by one or more of the following means:
Equipment grounding conductors of sizes 6 AWG and smaller shall be identified by a continuous green color or a continuous green color with one or more yellow stripes on the insulation or covering, except where bare. Conductors with insulation or individual covering that is green, green with one or more yellow stripes, or otherwise identified as permitted by this section shall not be used for ungrounded or grounded circuit conductors. (250.119)
Equipment grounding conductors 4 AWG and larger AWG that are not identified as required for conductors of sizes 6 AWG and smaller shall, at the time of installation, be permanently identified as an equipment grounding conductor at each end and at every point where the conductor is accessible, except where such conductors are bare.
The required identification for conductors 4 AWG and larger shall encircle the conductor and shall be accomplished by one of the following:
Insulation on the ungrounded conductors shall be a continuous color other than white, gray and green. [310.6(C)]
Exception: An insulated conductor that is part of a cable or flexible cord assembly and that has a white or gray finish or a finish marking with three continuous white or gray stripes shall be permitted to be used as an ungrounded conductor where it is permanently reidentified to indicate its use as an ungrounded conductor by marking tape, painting, or other effective means at all terminations and at each location where the conductor is visible and accessible. Identification shall encircle the insulation and shall be a color other than white, gray, and green. [200.7(C)(1), (2)]
All devices excluding panelboards, provided with terminals for the attachment of conductors and intended for connection to more than one side of the circuit shall have terminals properly marked for identification, except where the terminal intended to be connected to the grounded conductor is clearly evident. [200.10(A)]
Exception: Terminal identification shall not be required for devices that have a normal current rating of over 30 amperes, other than polarized attachment caps and polarized receptacles for attachment caps as required in Section E3407.4.2. [200.10(A) Exception]