This article provides readers with another high-level review of significant revisions that have been accepted at this stage in the 2011 National Electrical Code (NEC) development process. There were more than 5,000 proposals submitted and well over 1,000 proposals acted favorably by the Code-making panels (CMPs). Readers should understand that what is covered in this article could change based on public comments to the proposals or actions at the 2010 NFPA Annual Conference and Exposition. In the May issue of ELECTRICAL CONTRACTOR, we covered proposed changes up through Article 200, so let’s begin this part of the series with a look at some revisions in Articles 210 through 250.
Article 210 Branch Circuits
Proposal 2-77 Log No. 1735
(Revision) This section has been revised by adding a new sentence that requires ground-fault circuit interrupters (GFCI) to be located in readily accessible locations. The change clarifies that the test/reset features must be able to be operated by occupants. Previously, GFCI-protective devices could have been located remotely and inaccessible from points of use of such protected circuits and outlets.
Proposal 2-103 Log No. 1610
(Revision) This section has been revised to apply to all sinks, other than those already covered in Section 210.8(A)(6), which applies to all countertop surfaces in dwelling kitchens. Previously, the rule only applied to laundry, wet bar and utility sinks but left receptacles within 6 feet of other sinks without a requirement for GFCI protection. This revision clarifies the requirement and removes the subjectivity in enforcing this rule.
Proposal 2-122 Log No. 4178
(New) This new subdivision in 210.8(B) adds a requirement for GFCI protection in garages, service bays and other similar areas that may not carry a commercial repair garage designation or classification, thus Article 511 would not apply. This revision adds the GFCI protection where a vehicle could be driven into a garage bay and work could be performed on the vehicle using diagnostic tools or other equipment. The shock hazards are similar and GFCI protection should be provided for garage bays and locations that are not covered by 511.12.
Proposal 2-223 Log No. 2962
(New) This is a new subdivision under 210.52 addressing foyers and a requirement for receptacles. Foyers having an area greater than 60 square feet are now required to be provided with a receptacle outlet(s) for unbroken wall spaces measured 2 feet or more in width as required in 210.52(A)(2)(1). Foyers often are fairly large, leaving a lack of requirements for receptacles in those areas.
Proposal 2-276 Log No. 3700
(New) This new rule adds a floor receptacle requirement for meeting rooms of office buildings and hotels and motels. The new requirement also accounts for larger meeting rooms that are able to be subdivided with movable partitions. Listed floor boxes are required to be used for these installations. The new rule should help reduce extension cord use in these rooms or areas.
Article 225 Outside Branch Circuits and Feeders
Proposal 4-31 Log No. 3
(New) A new list item (5) has been added to 225.18. Minimum height requirements for conductors passing over a railroad now are included in Article 225; this makes minimum height requirements consistent with the National Electrical Safety Code (NESC). While it is clear in 90.2(B)(1) that the NEC does not apply to railway rolling stock, there are instances when overhead conductors within the NEC scope must pass over railroad tracks, such as for many industrial facilities.
Proposal 4-35 Log No. 307
(New) This new section adds requirements for sealing raceways for feeder raceways entering a building or structure from an underground distribution system. It refers to Section 300.5(G) and applies to spare raceways. The sealant has to be identified for use with the cable insulation, shield or other components. Although the new language mentions “sealant,” there also are some types of fittings that can be installed to meet the raceway-sealing requirement.
Article 230 Services
Section 230.24(A) Ex. No. 5
Proposal 4-82 Log No. 454
(New) This new exception aligns this section with similar allowances provided in the NESC. The new exception relaxes the minimum height requirements for the service-entrance conductors to be a minimum of 3 feet above the roof if the area is guarded or inaccessible. The terms guarded and isolated are defined in Article 100 of the NEC to assist users in clarifying installations that could qualify for this exception. It should be noted that this new exception is limited to service installations not exceeding 300 volts, which differs from the NESC provisions addressing installations not exceeding 750 volts.
Section 230.54(A) and (B)
Proposal 4-122 Log No. 562
(Revision) The references to requirements in Section 314.15 have been deleted from this section. A new sentence has been added to require that service heads for conduit and cable installations be listed fittings. This revision improves usability by placing weather head fitting requirements within the section that addresses them rather than through a reference to another section of the Code.
Proposal 4-161 Log No. 2983
(Revision) The words “or feeder” have been added to this requirement. This revision clarifies that when a service disconnect is not readily accessible to occupants, the related branch circuit or feeder overcurrent devices must be located in a readily accessible location for occupant use if needed.
Article 240 Overcurrent Protection
Proposal 10-29 Log No. 190
(Revision) The revisions to this section provide more specific correlation to the provisions in 210.4(B) related to a means to simultaneously disconnect all ungrounded conductors of the circuit. When a breaker is connected in the branch circuit, it must meet the simultaneous disconnecting-means rule covered in 210.4(B), while also serving as the overcurrent protection for the branch circuit. Identified handle ties and common trip circuit breakers are common methods of satisfying these requirements.
Section 240.15(B)(2) and (3)
Proposal 10-39 Log No. 4466
(Revision) This section has been revised and expanded to improve clarity and usability regarding proper application of circuit breakers to which handle ties are installed to meet the simultaneous disconnect requirements in 210.4(B). This revision aligns the requirements in UL product safety standards for circuit breakers with the NEC. The UL White Book DIVQ guide information provides important information related to applying handle ties to single-pole or multipole breakers with the limitations of the product standard UL 489 as follows:
“Single-pole or multi-pole independent trip circuit breakers, with handle ties, rated 120/240 V AC, are suitable for use on multi-wire circuits with line-to-line or line-to-ground connected loads.
“2-pole independent trip breakers and single-pole breakers with handle ties, rated 120/240 V AC, are suitable for use in line-to-line single-phase circuits or line-to-line lighting and appliance branch circuits connected to 3-phase, 4-wire systems, provided the systems have a grounded neutral and the voltage to ground does not exceed 120 V.
“2-pole independent trip breakers and single-pole breakers with handle ties, rated 125/250 V DC, are suitable for use in line-to-line connected 3-wire DC circuits supplied from a system with a grounded neutral where the voltage to ground does not exceed 125 V.
“2-pole independent trip breakers and single-pole breakers with handle ties, rated 125/250 V (both AC and DC), are suitable for use in accordance with either of the above two paragraphs, as applicable.” *
*Courtesy of Underwriters Laboratories
The proposal will help prevent the misapplication of circuit breakers, particularly in light of the availability of two-pole and three-pole handle ties, which have come on the market in response to the addition of 210.4(B) in the 2008 NEC.
Proposal 10-72 Log No. 3877
(New) This new section requires the available short-circuit current to be field-marked on service and feeder equipment enclosures in other than dwelling units. The marking has to include the calculated available fault current for determining equipment ratings and the date the calculation was performed. The amount of available fault current can and does change over time, which can have serious consequences when equipment short-circuit current ratings are exceeded. This new requirement will help provide facility owners and other responsible parties with rules that help recognize when equipment ratings are not adequate as required. A similar proposal (1-183) has been accepted by CMP-1 to include this same field-marking requirement for service-equipment enclosures. Coordination and correlation between these two proposed changes is already underway. This new rule will assist enforcement and contractors in meeting the general requirements in 110.9 when equipment is first installed and when equipment is added to or retrofitted at a time after the initial installation.
Proposal 10-82 Log No. 3562
(New) This new section addresses noninstantaneous trip circuit breakers operating characteristics and methods to reduce energy levels when equipment has to be worked on, tested, inspected or maintained while energized. The first choice and best practice always is to establish an electrically safe work condition. The provisions of this section include three viable options to reduce the clearing time of overcurrent protective devices that have the benefits of reducing incident energy levels of the system. The three methods are to use zone-selective interlocks between overcurrent devices, differential relaying, or an energy-reducing maintenance switch with status indication. This revision places an installation requirement in the Code that offers a higher degree of arc-flash protection for employees and also greater equipment protection in the unfortunate event of an arcing fault.
Article 250 Grounding and Bonding
Section 250.21(B) and (C)
Proposal 5-85, 5-86a Log Nos. 578, CP 502
(Revision and New) This section has been revised to require the ground detection sensing equipment be connected as close as practical to the source where the system receives its supply. This reduces possibilities of ungrounded system-monitoring equipment being disconnected by the opening a branch circuit or feeder disconnects on the load side of the system source, removing the monitoring capability. A new subdivision (C) has been added to require that enclosures for ungrounded systems be legibly marked “Ungrounded System” at the source or first disconnecting means of the system. The marking shall be of sufficient durability to withstand the environment involved. This new marking requirement will help warn qualified people of ungrounded power systems and the unique characteristics associated with these systems.
Proposal 5-102 Log No. 3224
(Revision) This section covering grounding requirements for separately derived systems has been reorganized and revised to provide a more logical order and improve usability. Technical revisions include a requirement that the system-bonding jumper not extend beyond the enclosure where it originates. The connection of a grounding-electrode conductor tap to a common grounding-electrode conductor is required to be made with a connector listed as grounding and bonding equipment instead of just a listed connector providing consistency with that connection required for services. A new subdivision (C) addresses outdoor sources and requires a grounding-electrode connection at the source location outside the building or structure served.
Proposal 5-150 Log No. 3705
(Revision) This section provides a list of suitable grounding electrodes. The term grounding electrode is defined in Article 100 and includes language referring to a direct connection between the electrode (conductive object) and the ground (earth). Section 250.52(A)(2) addresses metal frames of buildings or structures that qualify as grounding electrodes. This section has been revised to correlate directly with the definition of the term grounding electrode. Structural metal building frames meet the requirements for grounding electrodes where the metal frame is in direct contact with the ground (earth), or when it is connected directly to anchor bolts that are electrically connected to a concrete-encased electrode that complies with 250.52(A)(3). Structural metal building frames that serve as grounding-electrode conductors or conductive paths to qualifying electrodes are now covered in a new 250.68(C) as a result of coordinated proposals (5-212, Log No. 4013).
Sections 250.53(A)(2); 250.56
Proposals 5-159a, 5-174 Log Nos. CP 501, 1400
(New and Deleted) Section 250.53(A)(2) is a new requirement that a single electrode of the rod, pipe or plate types be supplemented by an additional electrode of any of the types provided in 250.52(A)(2) through (A)(8). An exception to this new rule permits a single electrode only where it has a resistance to ground not exceeding 25 ohms. In a coordinated proposal (5-174), Section 250.56 has been deleted.
Proposal 5-259 Log No. 4526
(New) This new rule restricts equipment-grounding conductors from being used as both grounding-electrode conductors and equipment-grounding conductors. It is recognized that grounding--electrode conductors can carry varying amounts of current in normal operation, especially where in a parallel path with the grounded conductor of the system. Equipment-grounding conductors should not carry current except during abnormal events such as a ground fault on the system. Compliance with the installation requirements for equipment-grounding conductors (250.120) and grounding-electrode conductors (250.64) is challenging, if not impossible, in many installations using a common (single) conductor. This revision clarifies that grounding-electrode conductors must be independent of equipment-grounding conductors.
Proposal 5-314 Log No. 3853
(Revision) Section 250.190, located in Part X of Article 250, addresses equipment-grounding conductors for medium and high-voltage circuits. This section has been revised to clarify that cable copper screen or ribbon shield or combination of both is not to be used as an equipment-grounding conductor, since it is typically undersized. The revision clarifies when separate equipment-grounding conductors must be installed with circuits of 1,000 volts and greater.
Article 280 Surge Arresters, Over 1 kV
Proposals 5-316, 5-317, 5-318, 5-319
Log Nos. 2730, 2863, 3592, 3772
(Deleted) Section 280.5, which required surge arresters of more than 1,000 volts to be listed, has been deleted from Article 280 based on claims that there are no surge arresters listed in this voltage rating. The listing requirement was new in the 2008 NEC. It should be noted that inspectors usually use listing as a basis for equipment approvals. More medium and high-voltage installations are falling under the requirements of the NEC. Listing electrical equipment provides a basis for approvals and some assurances that surge arresters meet applicable industry standards for safety.
The proposed revisions in Part II of this series of articles includes some significant changes proposed to the 2011 NEC. Not all changes proposed have been included in this article. The revisions resulted from the actions of the NEC technical committees at the Report on Proposals meeting in January 2009. These revisions could be affected by public comments to the proposals. The closing date for submitting public comments for any of the 2011 NEC change proposals is Oct. 23, 2009. Part 3 of the series on proposed changes will cover significant changes in Chapters 3, 4 and 5 of the Code.
JOHNSTON is NECA’s executive director of standards and safety. He is former director of education, codes and standards for IAEI; a member of the IBEW; and an active member of the NFPA Electrical Section, Education Section and the UL Electrical Council. Reach him at firstname.lastname@example.org.