Updates to 2014 NEC

NFPA 70, the National Electrical Code, will next be updated in 2014. Here's a look at what to expect.
By Justin Schultz, PE, LEED AP ID+C, Metro CD Engineering, Dublin, Ohio February 11, 2013

In 2011, 3745 proposals were submitted to NFPA to be considered for incorporation into the upcoming 2014 National Electrical Code (NEC). Technical committees reviewed these proposals, commented on them, and gave a recommended action (e.g., accept or reject) in a document called the report on proposals (ROP). The ROP was published and open for comments, which will be considered and addressed in the report on comments (ROC) to be presented for action at the NFPA Technical Meeting­­­­­­­­­­­ in 2013. The 2014 edition of the National Electrical Code will be available in the fall of 2013.

Figure 1: These low-voltage direct current (LVDC) grid interconnects are designed as a plug-and-play system to supply power to lighting fixtures and other electrical devices. This system provides safe, low-voltage dc distribution that eliminates ac to dc electrical power conversions at the device level. Courtesy: TE ConnectivitySome of the new NEC articles and changes are indicative of the code progressing to address new and evolving technologies. Proposals currently listed as accepted include four new articles, which are representative of technology advances that are either not currently covered in the NEC or require a more detailed set of requirements. The articles and changes serve the NEC’s mission to provide practical safeguards from the hazards that arise from using electricity.

In addition to changes addressing new technologies, there are also proposed changes to existing articles that will impact the status quo for electrical design. Electrical engineers and designers should take note, for example, of the additional locations requiring GFCI and AFCI protection (Article 210), the additional requirements for installations involving generators (Article 445), and the increased minimum number of receptacles required for patient bed locations and operating rooms (Article 517).

New articles

393 Low-voltage Suspended Ceiling Power Distribution Systems A proposed new article would cover installations of low-voltage suspended ceiling power distribution systems. These systems have similar characteristics to track lighting, where the ceiling grid is used as an electrical system for distributing power to lighting fixtures and other powered devices. The substantiation for adding this article states that alternative and renewable energy sources (e.g., photovoltaics, wind turbines, batteries, fuel cells, etc.) are increasingly being installed and, “this coupled with the reality that many of the loads installed ultimately use electricity in its dc form has renewed an interest in dc power and its distribution in buildings.” Proponents of these types of systems state that they enable lighting (and other device) reconfigurations without rewiring and require no ac/dc conversion (when directly connected to alternative energy sources).

Consider that most commercial buildings as well as many residential buildings today have suspended ceilings. The prevalent metal grid work can not only be used as support for acoustical ceiling tile and lighting fixtures, but also as a power distribution system. Details of the article include installation requirements, and uses permitted are limited to indoor dry locations for residential, commercial, and industrial installations. The system must be listed or an assembly of listed parts. The article limits systems to a maximum of 30 Vac or 60 Vdc Class 2 power.

646 Modular Data Centers This new article would define and list applicable requirements for a developing trend in data center architecture called modular data centers (MDCs). The unique customization and scalability of MDCs can vary their sizes from a large enclosure to a prefabricated building, while the equipment is typically not permanently installed. Details of the article include requirements for nameplate data, supply conductors and overcurrent protection, short-circuit current rating, field wiring compartments, and flexible power cable. Also listed are provisions for equipment, lighting, and work space requirements.

728 Fire Resistive Cable Systems A new article would list all requirements in one place for fire-resistive cable, conductor, and other system components used for survivability of critical circuits in fire conditions. Some of the installation requirements listed include mounting, supports, splices, raceways, and pulling lubricants.

750 Energy Management Systems A task group was appointed to focus on interconnection and energy management systems. The task group drafted this proposed article to address safety requirements for implementing infrastructure to allow the Smart Grid to actively manage energy management systems as a means to reduce energy costs or reduce peak power needs.

New or revised sections and subdivisions

100 Retrofit Kit A definition for “retrofit kit” is proposed to be added to Article 100. Retrofit kit would be defined as, “a general term for a complete listed subassembly of parts and devices for field conversion of utilization equipment.” New requirements for luminaire retrofit kits are also proposed to Section 410.6 (see below).

Figure 2: The EMerge Alliance occupied space power distribution system diagram illustrates a typical configuration for a room-level DC microgrid. The optional on-site DC power source (e.g., solar PV) would allow for direct integration of on-site renewable energy sources. Courtesy: EMerge Alliance110.17 Working Space Marking This proposed new section in Article 110 (Requirements for Electrical Installations) would require that equipment working space be identified on or adjacent to the equipment. The marking shall include the words, “CAUTION! AREA IN FRONT OF ELECTRICAL PANELS EQUIPMENT SHALL BE KEPT CLEAR FOR DEPTH: WIDTH: HEIGHT” with the required dimensions listed.

110.21(B) Field-Applied Markings This proposed new subdivision lists specific requirements for the content, color, durability, and suitability for field-applied markings and labels.

110.25 Lockable Disconnecting Means This new section would consolidate requirements for lockable disconnecting means into one section. The new text requires that where a disconnecting means is required to be lockable open, it shall be capable of being locked in the open position. It also ensures that the means for placing the lock remain in place.

110.26 Ground-Fault and Arc-Fault Circuit Interrupter Receptacles A new section would require that all ground-fault circuit-interrupter (GFCI) and outlet branch circuit type arc-fault circuit-interrupter (AFCI) receptacles be installed in a readily accessible location. The intent is to help facilitate the required periodic testing of these devices.

110.27(C)(2) and (3) Entrance to and Egress from Working Space, Personnel Doors These subdivisions currently list the requirements for two personnel doors where equipment rated 1200 A or more is installed containing overcurrent devices, switching devices, or control devices. The proposed amendment would reduce the requirement threshold to equipment rated 800 A or more. Another change would require that the egress doors have listed panic hardware (rather than allowing the use of other devices that are normally latched but open under simple pressure).

210.8(A)(9) GFCI Protection for Personnel, Dwelling Units This subdivision would add laundry areas to the current list of locations in dwelling units which currently require that all 125 V, single-phase, 15 A and 20 A receptacles have GFCI protection. The current list of locations includes bathrooms, garages, outdoors, crawl spaces, unfinished basements, kitchens, sinks, and boathouses.

210.12(A) Arc-Fault Circuit-Interrupter Protection, Dwelling Units Kitchens would be added to the list of rooms and areas in dwelling units that require AFCI protection for all 120 V, single-phase, 15 A and 20 A branch circuits supplying outlets. AFCIs were first introduced in the NEC in 1999 and were required in bedrooms. Their primary purpose is to protect the building from a fire. Newer releases of the NEC have added additional requirements and spaces where AFCIs are required. This proposed change is the next incremental step toward AFCI protection of all 120 V, 15 A and 20 A branch circuits in dwelling units.

Another revision would recognize use of a listed outlet branch circuit type AFCI installed at the first outlet on the branch circuit. In order to use AFCI outlet devices, the following four specific conditions must be met:

(a) The branch circuit overcurrent protection device shall be a listed circuit breaker having an instantaneous trip not exceeding 300 A.

(b) The branch circuit wiring shall be continuous from the branch circuit overcurrent device to the outlet branch circuit arc-fault circuit interrupter.

(c) The maximum length of the branch circuit wiring from the branch circuit overcurrent device to the first outlet shall not exceed 50 ft for a 14 AWG or 70 ft for a 12 AWG conductor.

(d) The first outlet box in the branch circuit shall be identified.

210.17 Electric Vehicle Branch Circuit The proposed new section to Article 210 (Branch Circuits) would require that outlet(s) intended for the purpose of charging electric vehicles be supplied by a separate, dedicated branch circuit.

210.64 Electrical Service Areas A new section would require that at least one 15 A or 20 A receptacle outlet be installed within 50 ft of the electrical service equipment (except for in one- and two-family dwellings). The new receptacle requirement is intended to facilitate use of portable electrical equipment for testing and servicing purposes.

240.11 Oversized Ungrounded Conductors The proposed new section to Article 240 (Overcurrent Protection) would require marking or tagging of ungrounded conductors that are increased in size for voltage drop or derating purposes. The mark or tag shall be located at the point where the conductors receive their supply. An exception would be provided for conditions where maintenance and engineering supervision ensure that only qualified personnel document, monitor, and service the equipment.

250.122(F) Conductors in Parallel This section would be amended to clarify that where conductors are run in parallel, the equipment grounding conductors shall not be required to be larger than the largest ungrounded conductor.

250.194 Grounding and Bonding of Fences and Other Metal Structures This proposed new section would provide new rules for bonding and grounding metal fences and metal structures, including guy wires. The requirements are intended to limit step, touch, and transfer voltages.

310.15(B)(7) 120/240 V, Single-Phase Dwelling Services and Feeders The proposed change would replace the existing Table 310.15(B)(7) with text stating that 83% of the 230.79 service ampere rating shall be permitted to be used as the minimum ampacity to determine the size of the ungrounded conductors. Although the reduction in minimum ampacity is the same as permitted in the existing table, the intent is to present the requirements in a user-friendly format. An example would be referenced in Annex D to provide more information on how to apply the new language.

330.30(D) Unsupported Cables The new subdivision would allow metal-clad cable (type MC) to be unsupported in lengths up to 3 ft for equipment flexibility reasons or to minimize transmission of vibration.

Figure 3: Modular data centers allow the use of outside air in the cooling systems, thereby limiting the use of air conditioning during colder months in cool climates. The HP EcoPOD modular data center is an example of a developing trend in data center architecture. Courtesy: HP400.7 Uses Permitted The proposed change to Article 400 (Flexible Cords and Cables) would allow use of a flexible cord or cable for connection of accessory equipment associated with mechanical equipment, alarms, or antennas. The nondetachable power supply cord must be 6 ft or less and the equipment must be above an accessible ceiling or dropped ceiling to meet this intent. Also, the installation shall not be prohibited by 300.22 to qualify as a permitted use.

404.2(C) Switches Controlling Lighting Loads A new proposed exception would exempt switch locations (from providing a grounded circuit conductor at the switch location) where snap switches with integral enclosures complying with 300.15(E) control the lighting loads.

Another exception would exempt the grounded circuit conductor requirement, such that where multiple switches (e.g., three- or four-way) control the same lighting load in an interior room or space, the grounded circuit conductor shall not be required at each location if one has been provided at one or more switching points visible from most areas within the room.

406.3(E) Controlled Receptacle Marking This new subdivision would require the use of a new marking symbol for receptacles that are controlled by an automatic control device or BAS. The requirement applies to nonlocking-type 125 V, 15 A and 20 A receptacles. Note that in the 2010 version of ASHRAE 90.1, 50% of all 125 V, 15 A and 20 A receptacles shall be controlled by an automatic control device for private offices, open offices, and computer classrooms (this includes receptacles in modular partition walls). As the new energy codes and future versions of U.S. Green Building Council LEED are adopted, this receptacle marking requirement will become much more prevalent.

406.5 Receptacle Mounting One change to this section would clarify that drywall screws shall not be used to fasten receptacles to boxes.

Currently receptacles mounted in countertops and similar work surfaces are not permitted to be mounted in the face-up position in dwelling units. Another proposed change would expand this restriction to apply to all occupancies.

A new subdivision would require that receptacles installed in floors, seating areas, and other similar surfaces may only be installed in a face-up position if the assembly is listed for that application.

406.15 Dimmer Controlled Receptacles A new section would clarify that a receptacle supply lighting load shall only be connected to a dimmer if the plug and receptacle combination is a nonstandard configuration type that is specifically listed and identified for each such unique combination.

410.6 Listing Required In addition to luminaires and lampholders, this amendment would require that retrofit kits be listed.

410.10(F) Luminaires Installed in or Under Roof Decking This new subdivision would restrict luminaires from being installed within 1.5 in. from the lowest surface of metal-corrugated sheet roof decking. The restriction is already in place for cables, raceways, and boxes (300.4(E)), but this change would extend the restriction to luminaires. The intent is to limit physical damage to the luminaire and its associated equipment (e.g., ballast and transformer) when screws and fasteners are added to repair or replace the roof decking, membrane, and insulating materials.

440.9 Grounding and Bonding, Air-Conditioning and Refrigerating Equipment A new section would require that an equipment grounding conductor be provided where air conditioning and refrigerating equipment is installed outdoors with either liquidtight flexible nonmetallic conduit (type LFMC) or electrical metallic tubing (type EMT). A related change to 350.60 would require that a wire-type equipment grounding conductor be installed for outdoor HVAC installations using LFMC, with exception requirements listed for industrial, commercial, and institutional installations.

445.11 Marking, Generators Additional marking would now be required by the generator manufacturer indicating whether or not the neutral is bonded to the generator frame. If the bonding is field-modified, additional marking would be required to again indicate whether or not the neutral is bonded to the generator frame.

445.20 GFCI Protection for Receptacles on Portable Generators A new section would require that all 125 V, 15 A and 20 A receptacles that are part of a 15 kW or smaller, portable generator have GFCI protection. The GFCI protection shall be integral to the generator or receptacle. The intent is to reduce possibilities of shock hazards for use of portable generators in less than ideal conditions.

490.25 Backfeed A proposed new section in Article 490 (Equipment, Over 600 V, Nominal) would add the following signage requirements to installations over 600V where the possibility of backfeed exists:

(a) A permanent sign in accordance with 110.21(B) shall be installed on the disconnecting means enclosure or immediately adjacent to open disconnecting means with the following words or equivalent: “DANGER — CONTACTS ON EITHER SIDE OF THIS DEVICE MAY BE ENERGIZED BY BACKFEED.”

(b) A permanent and legible single-line diagram of the local switching arrangement, clearly identifying each point of connection to the high-voltage section, shall be provided within sight of each point of connection.

517.18(B) Patient Bed Location Receptacles In the 2011 NEC, patient bed locations for general care areas are required to have a minimum of four receptacles, which shall be hospital-grade single, duplex, or quadruplex type, or any combination of the three. The proposed change for 2014 would increase this requirement to eight receptacles. The substantiation for the change is to coordinate requirements between the NEC and NFPA 99, Heath Care Facilities Code.

517.19(B) Patient Bed Location Receptacles In the 2011 NEC, patient bed locations for critical care areas are required to have a minimum of six receptacles. The proposed change for 2014 would increase this requirement to fourteen receptacles, with a minimum of one of the receptacles to be connected to either the normal system branch or the critical system branch. Again, the substantiation for the change is to coordinate requirements between the NEC and NFPA 99, and the receptacles shall be hospital-grade single, duplex, or quadruplex type, or any combination of the three.

517.19(C) Operating Room Receptacles A new subdivision would list receptacle requirements for operating rooms, A minimum of 36 receptacles would be required in each operating room, with a minimum of 12 receptacles on either the normal system branch or the critical system branch. Receptacles shall be hospital-grade single, duplex, or a combination of both.

625 Electric Vehicle Charging and Supply Equipment Systems This article would be renamed and reorganized with several changes, the most notable of which are as follows. Definitions for “electric vehicle charging system” and “electric vehicle supply equipment system” have been added (625.2). Where an automatic load management system is used, the maximum electric vehicle supply equipment load on a service or feeder would be limited to the maximum load permitted by the automatic load management system (625.12). A new section (625.17) lists requirements for cords and cables (e.g., types, ratings, lengths). Electric vehicle branch circuits would be required to be labeled, “For use with electric vehicle supply equipment (or electric vehicle charging system)” (625.30). Requirements would also be expanded for cord and plug supply equipment connections (625.44).

Figure 4: Electric vehicle charging systems provide a convenient means to charge vehicles that plug in instead of fueling up. Proposed changes to the NEC list additional requirements for these systems. Courtesy: GE690.12 Arrays on Buildings Response to Emergency Shutdown A new section in Article 690 (Solar Photovoltaic Systems) is proposed to increase the electrical and fire safety of photovoltaic (PV) systems on buildings—in particular, for the emergency responders working on power lines that may potentially contain live PV circuits. For PV systems installed on roofs of buildings, PV source circuits would be required to be de-energized within 10 seconds of when emergency shutdown is initiated or when the PV power source disconnecting means is opened. Additionally, the voltage at the module and module connectors shall be limited to 80 V or less when the source circuits are de-energized.

700.19 Multi-wire Branch Circuits A proposed new section to Article 700 (Emergency Systems) would prohibit emergency lighting and power branch circuits from being part of a multi-wire branch circuit. The intent is to prevent the unnecessary opening of the other one or two poles of a multi-wire branch circuit because of an overload, ground fault, or short-circuit on one pole of the multi-wire branch circuit. Prohibiting multi-wire branch circuits for emergency lighting and power branch circuits would prevent a trip in one emergency circuit from otherwise unnecessarily tripping other circuits, due to the circuit being supplied by either a multi-pole circuit breaker or single-pole circuit breakers sharing a common handle tie.

More Information

This article is meant to highlight some of the more important proposed changes of interest to consultants and specifiers. The changes listed are also limited to those that are currently listed as accepted in the RPO. As the list in this article is not comprehensive, there may be other substantive and important changes relevant to your field of work. Please review the 2013 ROP for more information, including all of the proposed changes.

Justin Schultz is a lead electrical engineer at Metro CD Engineering and serves as education chairman and board member for his local Illuminating Engineering Society (IES) section. He is a 2011 Consulting-Specifying Engineer 40 Under 40 winner.