I have been monitoring several NEC panel meetings virtually, and the members are becoming old pros at meeting online. The 18 NEC Code-Making Panels (CMPs) are currently considering public comments on the actions they developed during the first draft stage. Here are some things that came up.
NEC Style Manual improvements
There was a major rewrite of the NEC Style Manual. This document establishes how the NEC is put together. It isn’t an exciting read, but following it consistently makes the Code easier to understand. With so many Code authors and 18 panels developing the revisions, consistency is a must.
The NEC Style Manual requires every article to have a scope statement. Until now, all articles did, except Article 90. However, Article 90 contained the scope of the entire Code. To address this, CMP 1 developed a scope for Article 90. Section 90.2 is still important to lay out what the rest of the Code does and doesn’t cover. The new title is “Use and Application.” What was previously in 90.1 has been integrated into 90.2. Consistency has been a hallmark of the NEC , and it is introduced here with a practical solution.
Speaking of scopes, Article 500’s scope is odd because it is for articles 500 through 504 and has been so since the 1959 NEC . Article 504 was added to the scope when it was added to the Code. Each of those articles also had its own article scope. CMP 14 developed a revision to limit the scope to Article 500. Articles 505 and 506 were also revised so they are no longer dependent on any other articles.
There are several instances of long paragraphs expressing Code requirements. In the 2023 NEC, many of these longer paragraphs have been changed into list format. I have found all of them to be an improvement because it can be difficult to determine how many of the conditions apply to each technique and what modifies what.
All definitions have been moved into Article 100. In previous Code cycles, definitions existed in a number of places. Article 100 was where the definitions that applied throughout the Code were located. Before the 2020 cycle, Article 100 consisted of two parts: Part I, “General,” and Part II applied to installations over 1,000V nominal. A new Part III was created for definitions for hazardous (classified) locations in the 2020 Code. For 2023, the panels have all worked on moving all definitions to Article 100.
In the revised Article 100, there are no parts. Definitions are simply arranged alphabetically. Since some definitions appear in a form such as “service conductors, overhead,” there will be a parenthetical form of the term that appears as “(Overhead service conductors).” Although this doesn’t add value to the printed book, terms can be more easily searched for electronically.
Placing all the terms in the same article was a big challenge, because some terms required modification if they were to appear in Article 100. When they appeared in individual articles, most of them only applied within that article. During the 2020 cycle, some definitions were identified as applying throughout the Code, and most of those applied to wiring methods.
New tagging method
Since the 2017 Code, definitions have been tagged to indicate which panel is responsible for the definition. If the definition only applies to one article, the article number will appear after the definition. Some definitions are extracted from other NFPA documents; those definitions will indicate the source document and the definition location. NFPA documents other than the NEC and NFPA 70E number their definitions.
Some terms received new definitions, such as “fault-managed power.” This definition is key to understanding the proposed new Article 726, “Class 4 Power systems.” The term “likely to become energized” appears in 25 places in the 2020 NEC, but it required judgment to determine what that meant in a given installation. Oddly, it was on a list of standard terms in the NEC Style Manual. That definition is being added to the NEC as follows: “Likely to Become Energized. Conductive material that could become energized because of electrical insulation or electrical spacing failure.”
Selection of proposed changes
This is a random selection of proposed changes, so far:
In Section 110.3(B), the informational note points out that QR codes can be used to provide installation and use instructions to help with compliance with 110.3(B).
The term “neat and workmanlike” is vague, but inspectors have been able to write violations based on the theory that “I know it when I see it.” The proposed language change is to refer to the expected minimum work quality as “professional and skillful.”
Reconditioned equipment was a hot topic for the 2020 Code. A task group reviewed the Code’s requirements. Section 110.20 indicates that equipment is generally permitted to be reconditioned, unless prohibited elsewhere in the Code.
Reconditioning must be performed with identified replacement parts and verified under applicable standards. If listing is required, the equipment must be listed or field labeled as reconditioned. If listing is not required, it must be listed or field labeled as reconditioned or reconditioned in accordance with OEM instructions. If listing, field labeling and OEM guidance are not available, AHJ approval is permitted with documentation of the changes. In addition, there are new marking requirements proposed for 110.21(A)(2) for reconditioned equipment.
In several places throughout the Code, it is proposed to permit copper-clad aluminum conductors in sizes as small as 14 AWG. Copper-clad aluminum conductors have permitted ampacities that mirror those of the same size aluminum conductors. However, the smallest size of aluminum conductor permitted by the Code is 12 AWG. CCA conductors that are 14 AWG would have an ampacity of 10A. Circuits wired with 14 AWG will not be permitted to supply receptacles.
Wall space requirements have been clarified to indicate that the wall space behind fixed appliances will not need to be considered as requiring receptacles. This is a practical improvement to not require a receptacle in an inaccessible space.
During the 2020 cycle, a surge protection requirement was added for dwelling unit services. Surge protection is now proposed for feeders that supply dwelling units, dormitory units, hotel/motel guest rooms and suites and patient sleeping rooms in nursing homes and limited-care facilities. We have all become dependent on sensitive electronic equipment, so this will provide needed protection.
Section 110.22(A) proposes to improve the marking requirements for disconnecting means. They will be required to be marked to indicate their purpose, unless its use is obvious, and to indicate where the upstream power source is. This latter does not apply to one- or two-family dwellings. It is intended to make it easier for service personnel to identify and locate the upstream disconnecting means, which may be needed for maintenance purposes.
Dedicated equipment space requirements in Section 110.26(E) may be expanded to include service equipment in one- and two-family dwellings. This would include the emergency disconnect required by 230.85.
There have been a couple of changes to “high impedance grounded neutral systems.” First, they are now simply referred to as “impedance grounded systems.” There was never a distinction added between low- and high-impedance grounded systems. Second, the conductor that connects the impedance to the system ground is now called the impedance grounded conductor.
The GFCI requirements in Section 210.8 will be updated in 2023 as they have for the last several cycles. GFCI protection is required to be listed. This section also requires Class A GFCI protection, which are the devices that trip at 4–6 milliamps. The greatest interest will be in 210.8(F). There have been reports of frequent trips for some mini split-type air conditioning units. A TIA on this section was issued in August, with implementation in Jan. 1, 2023, for mini split units.
Type P cable was introduced in the 2020 Code. In the 2023 Code, the cable will also be referred to as “industrial mobile cable, Type IM.”
There were several actions to harmonize requirements for similar occupancies, such as for datum planes distances and equipotential plane bonding. There appear to be a number of good changes. Some don’t move the needle technically, but do improve readability.
We now await the Code-making panels' actions on the public comments.