2008 NEC® Changes: Chapter 2 (Part 2)
NEC Digest®, December 2006 (necdigest®, National Electrical Code®, and NEC® are registered trademarks of the National Fire Protection Association, Inc., Quincy, MA 02169)
By James Stallcup, Sr. and Mark Ode
In the second of a series discussing proposed changes to the 2008 National Electrical Code® (NEC®), the authors cover important changes to Chapter 2. To help simplify and clarify each change, words that have been deleted are shown with a strike through and words that have been added are underlined.
2008 NEC Products
2005 NEC
210.4 Multiwire Branch Circuits
(A) General. Branch circuits recognized by this article shall be permitted as multiwire circuits. A multiwire circuit shall be permitted to be considered as multiple circuits. All conductors shall originate from the same panelboard or similar distribution equipment.
FPN: A 3-phase, 4-wire, wye-connected power system used to supply power to nonlinear loads may necessitate that the power system design allow for the possibility of high harmonic neutral currents.
(B) Devices or Equipment Disconnecting Means. Where a multiwire branch circuit supplies more than one device or equipment on the same yoke, a means shall be provided to disconnect simultaneously all ungrounded conductors supplying those devices or equipment at the point where the branch circuit originates.
2008 NEC
210.4 Multiwire Branch Circuits
(A) General. Branch circuits recognized by this article shall be permitted as multiwire circuits. A multiwire circuit shall be permitted to be considered as multiple circuits. All conductors of a multiwire branch circuit shall originate from the same panelboard or similar distribution equipment.
FPN: A 3-phase, 4-wire, wye-connected power system used to supply power to nonlinear loads may necessitate that the power system design allow for the possibility of high harmonic neutral currents.
(B) Disconnecting Means. Each multiwire branch circuit shall be provided with a means that will simultaneously disconnect all ungrounded conductors at the point where the branch circuit originates.
Author’s Comment: There were two reasons for the changes to the text in this section. The first reason was to clarify that all conductors of a multiwire branch circuit must originate from the same panelboard or distribution equipment. The change in (B) was done to emphasize the safety concerns associated with unintentional voltage being present on multiwire branch circuits during maintenance. Deleting the text that applied simultaneous disconnecting requirements for a multiwire branch circuit to a single device or equipment on the same yoke will require simultaneous disconnect of all ungrounded conductors on any multiwire branch circuit at its origin.
2005 NEC
210.5 Identification for Branch Circuits
(C) Ungrounded Conductors. Where the premises wiring system has branch circuits supplied from more than one nominal voltage system, each ungrounded conductor of a branch circuit, where accessible, shall be identified by system. The means of identification shall be permitted to be by separate color coding, marking tape, tagging, or other approved means and shall be permanently posted at each branch-circuit panelboard or similar branch-circuit distribution equipment.
2008 NEC
210.5 Identification for Branch Circuits
(C) Ungrounded Conductors. Where the premises wiring system has branch circuits supplied from more than one nominal voltage system, each ungrounded conductor of a branch circuit shall be identified by system at all termination, connection, and splice points. The means of identification shall be permitted to be by separate color coding, marking tape, tagging, or other approved means. The means of identification shall be documented in a manner that is readily available or shall be permanently posted at each branch-circuit panelboard or similar branch-circuit distribution equipment.
Author’s Comment: The current wording in the 2005 NEC requires marking of the conductors at every conduit fitting and pull box or any other location where the branch circuit is accessible. The locations where the branch circuit is terminated, connected or spliced are the critical locations where the marking is needed. The revised wording would account for branch circuits installed as cables and branch circuits installed as single conductors in raceways. The change also expands the methods that can be used for identification to permit documentation that is readily available or permanent posting at the panelboard or distribution equipment.
2005 NEC
210.8 Ground-Fault Circuit-Interrupter Protection for Personnel
(A) Dwelling Units. All 125-volt, single-phase, 15- and 20-ampere receptacles installed in the locations specified in (1) through (8) shall have ground-fault circuit-interrupter protection for personnel.
(2)Garages, and also accessory buildings that have a floor located at or below grade level not intended as habitable rooms and limited to storage areas, work areas, and areas of similar use
Exception No. 1 to (2): Receptacles that are not readily accessible.
Exception No. 2 to (2): A single receptacle or a duplex receptacle for two appliances located within dedicated space for each appliance that, in normal use, is not easily moved from one place to another and that is cord-and-plug connected in accordance with 400.7(A)(6), (A)(7), or (A)(8).
Receptacles installed under the exceptions to 210.8(A)(2) shall not be considered as meeting the requirements of 210.52(G).
(5) Unfinished basements—for purposes of this section, unfinished basements are defined as portions or areas of the basement not intended as habitable rooms and limited to storage areas, work areas, and the like
Exception No. 1 to (5): Receptacles that are not readily accessible.
Exception No. 2 to (5): A single receptacle or a duplex receptacle for two appliances located within dedicated space for each appliance that, in normal use, is not easily moved from one place to another and that is cord-and-plug connected in accordance with 400.7(A)(6), (A)(7), or (A)(8).
Exception No. 3 to (5): A receptacle supplying only a permanently installed fire alarm or burglar alarm system shall not be required to have ground-fault circuit-interrupter protection.
Receptacles installed under the exception s to 210.8(A)(5) shall not be considered as meeting the requirements of 210.52(G).
210.8 Ground-Fault Circuit-Interrupter Protection for Personnel
(A) Dwelling Units. All 125-volt, single-phase, 15- and 20-ampere receptacles installed in the locations specified in (1) through (8) shall have ground-fault circuit-interrupter protection for personnel.
(2) Garages, and also accessory buildings that have a floor located at or below grade level not intended as habitable rooms and limited to storage areas, work areas, and areas of similar use
(5) Unfinished basements—for purposes of this section, unfinished basements are defined as portions or areas of the basement not intended as habitable rooms and limited to storage areas, work areas, and the like
Exception to (5): A receptacle supplying only a permanently installed fire alarm or burglar alarm system shall not be required to have ground-fault circuit-interrupter protection.
Receptacles installed under the exception s to 210.8(A)(5) shall not be considered as meeting the requirements of 210.52(G).
Author’s Comment: The two exceptions permitting receptacles that were not readily accessible and single or duplex receptacles for two appliances within a dedicated space for each appliance to not have GFCI protection for personnel in garages and unfinished basements were deleted. The substantiation in the proposal and the discussion during the panel deliberation indicated that the present generation of GFCI devices do not have the problems of nuisance tripping that plagued earlier devices.
2008 NEC
210.8 Ground-Fault Circuit-Interrupter Protection for Personnel
(B) Other Than Dwelling Units. All 125-volt, single-phase, 15- and 20-ampere receptacles installed in the locations specified in (1) through (5) shall have ground-fault circuit-interrupter protection for personnel:
(3) Rooftops
(4) Outdoors
Exception No. 1 to (3) and (4): Receptacles that are not readily accessible and are supplied from a dedicated branch circuit for electric snow-melting or deicing equipment shall be permitted to be installed in accordance with the applicable provisions of Article 426.
Exception No. 2 to (4): In industrial establishments only, where the conditions of maintenance and supervision ensure that only qualified personnel are involved, GFCI protection shall not be required on receptacles that are limited to use with equipment qualified under an assured equipment grounding conductor program as specified in 590.6(B)(2).
Author’s Comment: This revision requires GFCI protection for all 15- and 20-ampere, 125-volt single-phase receptacles installed outdoors, rather than just those in public spaces. An exception was added to exempt those receptacles in industrial establishments only, where the conditions of maintenance and supervision ensure that only qualified personnel are involved, that are limited to use with equipment qualified under an assured equipment grounding conductor program as specified in 590.6(B)(2).
2005 NEC
210.8 Ground-Fault Circuit-Interrupter Protection for Personnel
(B) Other Than Dwelling Units. All 125-volt, single-phase, 15- and 20-ampere receptacles installed in the locations specified in (1) through (5) shall have ground-fault circuit-interrupter protection for personnel:
(2) Commercial and institutional kitchens—for the purposes of this section, a kitchen is an area with a sink and permanent facilities for food preparation and cooking
2008 NEC
210.8 Ground-Fault Circuit-Interrupter Protection for Personnel
(B) Other Than Dwelling Units. All 125-volt, single-phase, 15- and 20-ampere receptacles installed in the locations specified in (1) through (5) shall have ground-fault circuit-interrupter protection for personnel:
(2) Commercial, institutional, and other nonresidential kitchens—for the purposes of this requirement, a kitchen is defined as an area with a sink and permanent facilities for food preparation and cooking
Author’s Comment: An office “break area” with a sink and permanent facilities for food preparation and cooking does not really qualify as either commercial or institutional, but the break area or room with a sink and permanent cooking facilities has the same shock hazard potential. This change clarifies that these break rooms or areas fall under the requirements of this section for ground-fault protection.
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Reprinted with permission from necdigest®, Copyright 2007, National Fire Protection Association, Quincy, MA 02169
necdigest®, National Electrical Code®, and NEC® are registered trademarks of the National Fire Protection Association, Inc., Quincy, MA 02169
