This is the third installment in a series of articles summarizing about 220 significant changes in the 2002 NEC. These articles do not cover every change, and they are not intended to provide a full explanation of the reasons for the changes, as that information is readily available on NFPA's Web page on the NEC, www.necdirect.org, and will also be available in continuing education courses, books and videos on the changes.Article 600 — Electric Signs and Outline Lighting
Section 600.21(F) — Ballasts, transformers and electronic power supplies located above suspended ceilings may not be connected to the branch circuit by flexible cord.
Section 600.32(A) — The minimum size of the raceway used for neon secondary circuits is ½ in.Article 604 — Manufactured Wiring Systems
Section 604.6(A)(1) and (2) — Appropriate types of limited energy circuit cables may be used in manufactured wiring systems intended for use with limited energy circuits.
Section 680.27(B)(604.6(E)) — Support requirements for manufactured wiring must be in accordance with the wiring method used.Article 620 — Elevators, Dumbwaiters, Escalators, Moving Walks, Wheelchair Lifts and Stairway Chair Lifts
Throughout this article, the requirements for installations in “Machinery Rooms and Machine Spaces” are now also applied to “Control Rooms and Control Spaces.” Modern equipment is not confined to the traditional “Elevator Equipment Rooms,” so this change applies the article to other spaces used for elevator equipment and controls.
Section 620.51 — A new exception permits general-use snap switches for disconnecting means for wheelchair lifts where the lift is 2 hp or less in accordance with Section 430.109(C).Article 640 — Audio Signal Processing, Amplification and Reproduction Equipment
Section 640.3(A) — Accessible portions of abandoned cables must be removed. This section applies only to audio distribution cables, but similar changes have been made in Chapters 7 and 8 for other limited-energy cables.
Section 640.6 — Cables run on the outside surfaces of ceilings and walls must be supported from building structural components and installed in such a manner that the cables will not be damaged by normal building use or by the support methods. Other cables (not installed on outside surfaces) must be installed neat and workmanlike. All cables must be protected in accordance with 300.4(D). (Section 300.11 also applies to Article 640 wiring.)Article 645 — Information Technology Equipment
Section 645.5(D)(5)(c) — Type ITC cable has been added to the list of cable types for use in raised floors. However, Type ITC cable is restricted to industrial occupancies by Article 727.
Section 645.5(D)(6) — Abandoned cables must be removed from raised floor spaces.Article 647 — Sensitive Electronic Equipment
This new article was mostly extracted from Article 530 and revised. It covers 60/120V systems, commonly referred to as “Technical Power.” Applications are limited to supervised areas of commercial and industrial occupancies. “Commercial and industrial” in this sense is intended to mean primarily non-residential, and is not intended to prohibit the use of these systems in schools, for example. Ordinary equipment and wiring devices may be used but must be marked. Voltage drop is limited.Article 665 — Induction and Dielectric Heating Equipment
This article was rewritten and induction welding and melting processes were added to the scope of the article.Article 680 — Swimming Pools, Fountains and Similar Installations
Article 680 was rewritten, primarily to improve usability. The subject areas (Parts) now stand alone without reference to other Parts. The term “specified body of water” has been added and includes all bodies of water covered by Article 680.
Section 680.6 — Grounding requirements were relocated, grouped in one place and clarified.
Section 680.12 — Requirements for “Maintenance Disconnects” have been clarified. Maintenance disconnects are required for all equipment except lighting and must be accessible and within sight of the equipment.
Section 680.22(A)(4) — Where the normal requirement for clearances of receptacles from pools cannot be met at a dwelling due to the dimensions of the lot, one GFCI-protected receptacle may be located closer than 10 ft but not less than 5 ft from the wall of the pool.
Section 680.22(C) — Switching devices may be installed closer than 5 ft from a pool if the device is listed for use within 5 ft from a pool.
Section 680.23 — One length is limited to 6 ft and the total length is limited to 10 ft when LFMC or LFNC are used for wiring underwater luminaires. Type LFNC-B is not limited in length.
Section 680.26(B)(1) — Encapsulated reinforcing in pool structures is not required to be bonded, but an alternate method of eliminating voltage gradients must be provided.
Section 680.26(B)(4) — Double-insulated pump motors are not to be bonded, but a bonding means must be provided in the vicinity for replacement motors that may not be double-insulated.
Section 680.27(B)(1) — The controller for an electrically operated pool cover must be located where the operator has a clear view of the entire pool.
Section 680.44(B) — Field-assembled spas and hot tubs that are three-phase, over 250V or over 50A are not required to have GFCI protection.
Section 680.57(C)(2) — Portable signs may not be put in or within 5 ft of pools or fountains.
Section 680.62(A)(2) — Therapeutic tubs, other than listed self-contained units, that are three-phase, over 250V or over 50A are not required to have GFCI protection.Article 690 — Solar Photovoltaic Systems
Section 690.14(C) — Disconnecting means for photovoltaic systems are not required to be suitable for use as service disconnects, but must meet service disconnect requirements with regard to location, marking, grouping and maximum numbers of devices.Article 692 — Fuel Cells
This new article covers an emerging technology. Requirements are similar to Article 690, and the systems are generally treated like separately derived systems. All equipment is required to be evaluated and listed for the purpose prior to installation.