Chapter Corner

No Code is Perfect: Corrections to the 2014 NEC

Posted in: Features, January/February 2014

perfect_insights.pngMistakes happen, to err is human, and it is not unusual for the first edition of a book to have typos. The Adventures of Huckleberry Finn holds the record for the most mistakes in a first printing. In general the more errors the first generation of a literary book has, the more valuable it is to a collector.

“Errata” is the plural form of the singular word erratum, and it means errors. An errata is most commonly issued shortly after a first edition is published.

The 2014 National Electrical Code® (NEC) is no exception. The development process takes three years. There are more than 500 people involved in the process. More than 3,700 proposals were submitted, and 1,600 comments considered before printing was started.

There are many changes in the 2014 edition of the NEC. The threshold voltage was revised from 600 to 1,000 Volts in a number of requirements. New articles were added covering low voltage suspended ceilings, modular data centers, fire resistive cable systems, and energy management systems. There are a number of new GFCI and AFCI requirements. The NEC has added a requirement for a rapid shutdown for photovoltaic systems on buildings. With all the changes, a few errors managed to creep into the NEC.

If you purchased the first edition of the National Electrical Code, make sure to download the errata sheet at

Below is a review of the corrections found in the errata sheet.

  1. Shading is used in the 2014 NEC to indicate changes from the 2011 edition of the NEC. In Section 200.7, shading should be removed from the first line of the title. Shading should be added to the words “or Gray” in the second line.

  2. Numbers in table 220.3 were transposed in the Section or (Part Column) of Table 220.3. Relating to the term “Electric vehicle charging system branch-circuit and feeder calculations,” change the section reference to 625.41.

  3. The word “non” makes a big difference to those required to comply with this change. The title of Table 220.44 should be revised to read: “Table 220.44 Demand Factors for Non-Dwelling Receptacle Loads.”

  4. This change was understood in the past code book; however it does provide some clarity to the reader. In Section 400.4, the first sentence should read “Flexible cords and flexible cables shall conform to the description in Table 400.4."

  5. There were two Part II’s in Article 400 so the second one was renamed Part III. The numbering was correct in the 2011 NEC.

  6. Article 422.51(A), titled Vending Machines, please delete the words “identified for portable use.” The result is: All cord and plug connected vending machines manufactured after January 1, 2005, will require GFCI protection as an integral part of the plug. Older machines must be connected to a GFCI outlet.
  7. Article 490.48 is a new section in the 2014 NEC. Please replace Section 490.48 in the 2014 NEC with the following:

    490.48. Substation Design, Documentation, and Required Diagram.

    (A) Design and Documentation. Substations shall be designed by a qualified licensed professional engineer. Where components or the entirety of the substation are listed by a qualified electrical testing laboratory, documentation of internal design features subject to the listing investigation shall not be required. The design shall address but not be limited to the following topics and the documentation of this design shall be made available to the authority having jurisdiction.

    (1) Clearances and exits

    (2) Electrical enclosures

    (3) Securing and support of electrical equipment

    (4) Fire protection

    (5) Safety ground connection provisions

    (6) Guarding live parts

    (7) Transformers and voltage regulation equipment

    (8) Conductor insulation, electrical and mechanical protection, isolation, and terminations

    (9) Application, arrangement, and disconnection of circuit breakers, switches, and fuses

    (10) Provisions for oil filled equipment

    (11) Switchgear

    (12) Surge arrestors

    (B) Diagram. A permanent single-line diagram of the switchgear shall be provided in a readily visible location within the same room or enclosed area with the switchgear and this diagram shall clearly identify interlocks, isolation means, and all possible sources of voltage to the installation under normal or emergency conditions, and the marking on the switchgear shall cross-reference the diagram. Exception: Where the equipment consists solely of a single cubicle or metal enclosed unit substation containing only one set of high-voltage switching devices, diagrams shall not be required.

  8. The section identifier at the top of page 390 should read 500.9 instead of 50.9.
  9. Please change the references in article 506.9(C)(2) on page 434 under the heading “Exception” to read as follows:

    Exception: Associated apparatus NOT suitable for installation in a hazardous (classified) location shall be required to be marked only with 506.9(C)(2)(2), (3), and (5), but BOTH the symbol AEx in 506.9(C)(2)(2) and the symbol for the type of protection in 506.9(C)(2)(3) shall be enclosed within the same square brackets; for example, [AEx iaD] or [AEx ia] IIIC.

  10. The title of Article 516 should be revised to add the word “or” to the title to read as follows: Spray Application, Dipping, Coating, and Printing Processes Using Flammable or Combustible Materials

  11. Replace Figure 516.3(D) (2) with the following:

  12. In Section 625.17(A)(1), change the cross-reference from 625.17(B)(1) to 625.17(B).

  13. In Section 645.15, delete the second sentence, which reads: “Power systems derived within listed information technology equipment that supply information technology systems through receptacles or cable assemblies supplied as part of this equipment shall not be considered separately derived for the purpose of applying 250.30.”

  14. Article 690.7(F) titled Disconnects and Overcurrent Protection should be deleted.

  15. The reference in the last line of Articles 690.56(A) should be changed from 690.31(E) to 690.31(G).

  16. Delete Figure 700.2 and its title “Emergency Systems.” Also, delete the words “See Figure 700.2” in the first paragraph of article 700.2, Definitions.

  17. Delete Figure 701.2 and its title “Legally Required Standby Systems.” Also, delete the words “See Figure 701.2” in the first paragraph of article 701.2, Definitions.

  18. Delete Figure 702.2 and its title “Optional Standby Systems.” Also, delete the words “See Figure 702.2” in the first paragraph of article 702.2, Definitions.

  19. Delete Figure 708.2 and its title “Critical Operations Power Systems.” Also, delete the words, “See Figure 708.2” in the second paragraph of article 708.2 titled, Critical Operations Power Systems.

  20. Change the (C) located at the top of page 70-664 to 705.12.
The above comments were made to the NEC Errata Issue Date of September 16, 2013 to Errata No. 70-14-1. Check for the most up-to-date errata information on the 2014 NEC.

John Masarick is Vice President of Codes & Standards at the IEC National office in Alexandria, Virginia. He can be reached at (703) 650-0053 or e-mail