Ecmweb 6768 Code Basics Oct 2014 Pr
Ecmweb 6768 Code Basics Oct 2014 Pr
Ecmweb 6768 Code Basics Oct 2014 Pr
Ecmweb 6768 Code Basics Oct 2014 Pr
Ecmweb 6768 Code Basics Oct 2014 Pr

Basic Requirements for Switches, Receptacles, Cord Connectors, and Caps

Oct. 18, 2014
Articles 404 and 406 provide the requirements for some of the most commonly connected branch circuit devices.

The requirements of Art. 404 apply to switches of all types, including snap (toggle) switches, dimmer switches, fan switches, knife switches, circuit breakers used as switches, and automatic switches, such as time clocks and timers.

The 2014 NEC heavily revised the requirement for having a neutral at switch locations. Why so much change? When a new, significant rule comes into the NEC, it often takes at least another revision cycle to work out the kinks because it’s difficult to anticipate every type of installation that a new rule will affect.

The 2014 NEC greatly expanded the areas where a neutral isn’t required, and it significantly cleans up the existing exceptions.

It also removed the text regarding framing cavities that are “open at the top or bottom” because even Code experts disagreed about what that exception meant. The 2014 NEC replaced that text with item two, which is easier to understand:

Fig. 1. This revised Code requirement is now much easier to understand.

404.2(C)(2) — A neutral isn’t required where the switch box can be accessed to add or replace a cable containing a neutral without damaging the finish of the building (Fig. 1).

Additional new allowances include 3-way and 4-way switches where the switches can “see” the entire room. In these instances, an occupancy sensor would be installed only at one or the other switch so there’s no reason to require a neutral at both.

Mounting snap switches

Unfortu-nately, it’s a common (and unsafe) practice to use drywall screws to attach receptacles and switches to boxes. Another bad, and probably more dangerous, practice is that of attaching luminaires to boxes using screws that weren’t designed, tested, and listed to support them. The NEC prohibits both of these practices.

When you install a snap switch in a recessed box, you must firmly seat the ears of the switch yoke against the finished wall surface. Screws for attaching a snap switch to a box must be machine screws matching the thread gauge or size of the screw holes in the box, unless otherwise allowed by the manufacturer’s instructions or unless part of a listed assembly [404.10(B)].

Note that this same screw requirement now applies to receptacles as well [406.5].

Receptacle rating and type

It’s becoming common for energy management systems to control receptacles in commercial buildings. These systems de-energize receptacles at a certain time of day, such as just after quitting time. But quitting time isn’t the same for everybody, so this presents a problem — especially when equipment such as a computer workstation is plugged into one of those receptacles.

Now all nonlocking, 125V, 15A and 20A receptacles that have an automatic means to remove power from the outlet (e.g., for energy management or building automation) must be marked with a specific “controlled receptacle” symbol placed on the receptacle. This symbol must be visible to users, so choose the location for the symbol with that in mind [406.3(E)] (Fig. 2).

Fig. 2. Don’t be caught off-guard when you start seeing this new symbol on select receptacles.

You don’t have to use this marking on wall switch-controlled receptacles used for lighting. In addition, see [210.70(A)(1) Exception No. 2].

Grounding type

Previous editions of the NEC provided the rule that receptacles must be of the grounding type but stated it as an exception. Now the requirement is in the opening statement of 406.4(A), and the NEC states it in positive text.

Receptacles installed on 15A and 20A branch circuits must be of the grounding type, unless used for replacements as permitted in 406.4(D)(2). Single receptacles must have an ampere rating not less than the rating of the branch circuit [210.21(B)(1)]. Multioutlet receptacles (such as duplex receptacles) must have a rating compliant with Table 210.21(B)(3) [406.4 (A)].

No face up

The NEC now prohibits installing receptacles face up in any countertop, not just those in dwelling units [406.5(E)]. The logic behind this also extends to seating areas and similar surfaces, with the new subsection 406.5(F) providing the requirements.

Why doesn’t this change apply to all floor receptacles? Floor boxes are typically listed without the receptacle, so they aren’t a listed assembly. Rather, they’re an assembly of listed parts.

Damp or wet locations

All 15A and 20A receptacles installed in a wet location must be within an enclosure that’s weatherproof when an attachment plug is inserted [406.9(B)(1)]. All nonlocking type 15A and 20A, 125V and 250V receptacles in a wet location must be listed as weather resistant. Receptacles rated 30A or more installed in a wet location must comply with (a) or (b):

(a) Wet Location Covers. A receptacle in a wet location, where the load isn’t attended while in use, must be installed in an enclosure that’s weatherproof when an attachment plug is inserted.

(b) Damp Location Covers. A receptacle (in a wet location) that will be used only while someone is in close proximity (e.g., one used with portable tools) can have an enclosure that’s weatherproof when the attachment plug is removed and the cover is closed.

Fig. 3. New “extra-duty” type covers should stand up to more abuse and last longer than their predecessors.

Finally, note that outlet box hoods now must be listed and identified for “extra-duty” use (Fig. 3). Why such a stringent requirement? Too many weatherproof covers were breaking off. Now that these must be “extra-duty,” we should see far fewer broken covers.

Tamper-resistant receptacles

On a tamper-resistant receptacle, inserting an object into one side of the receptacle doesn’t open the internal tamper-resistant shutter. The only way to open it is with simultaneous pressure from a 2- or 3-pronged plug.

The 2008 NEC introduced us to the concept of tamper-resistant receptacles. It specified where you must use them, and it did that with no exceptions. The 2011 NEC added guest rooms, guest suites, and child care facilities to the list of required places. The 2011 NEC also added some exceptions, but they were applicable only to dwelling units.

But if you don’t need these receptacles in some locations of dwellings, why do you need them in the same areas of nondwellings? The 2014 NEC solves the inconsistencies by combining all of the rules into one section [406.12]. Thus, the exceptions become applicable to all of the areas requiring these receptacles.

If installing receptacles in the following areas, they must be tamper-resistant:

(A) Dwelling Units. All nonlocking type 15A and 20A, 125V receptacles in the following areas of a dwelling unit [210.52] must be listed as tamper resistant.

Wall Space — 210.52(A)

Small-Appliance Circuit — 210.52(B)

Countertop Space — 210.52(C)

Bathroom Area — 210.52(D)

Outdoors — 210.52(E)

Laundry Area — 210.52(F)

Garage and Outbuildings — 210.52(G)

Hallways — 210.52(H)

(B) Hotel and Motel Guest Rooms and Guest Suites. All nonlocking type 15A and 20A, 125V receptacles in these locations must be listed as tamper resistant.

(C) Child Care Facilities. Nonlocking type 15A and 20A, 125V receptacles in these facilities must be listed as tamper resistant. A child care facility is a building/structure or portions thereof used for educational, supervision, or personal care services for five or more children seven years or less [406.2].

What about those exceptions? Receptacles don’t need to be tamper-resistant in these locations:

(1) More than 5½ ft above the floor.

(2) Where part of a luminaire or appliance.

(3) Within dedicated space for an appliance that in normal use isn’t easily moved from one place to another.

And nongrounding receptacles used for replacements as permitted in 406.4(D)(2)(a) don’t have to be tamper-resistant.

Dimmer-controlled receptacles

Connecting your floor lamp to a dimmer-controlled receptacle might seem like a good idea, but plugging your LED TV
into the same receptacle is not. The average homeowner may not realize this or may not remember that a particular receptacle is controlled by a dimmer switch.

Fig. 4. There are new rules in the 2014 NEC for dimmer-controlled receptacles.

To prevent damage to connected equipment, the NEC previously didn’t allow receptacles to be connected to a dimmer switch [404.14(E)]. Now it does, but only if the receptacle and plug are nonstandard. Also, these devices must be specifically listed and identified for each such unique combination [406.15] (Fig. 4). This way, there’s no risk of someone plugging in a piece of equipment that can become damaged.

Avoiding violations

Switches and receptacles are common types of branch circuit loads, and an electrician might install hundreds of them in a single year. As we’ve clearly seen in this article, the requirements for these have changed over the past few Code cycles.

The installation methods that were OK at one time might not be OK now. Has it been a while since you’ve reviewed your designs and installation practices against Articles 404 and 406? If so, spend some time doing that review so your installations comply with the requirements of the NEC revision adopted for the jurisdiction in which you’re working.

Holt is the owner of Mike Holt Enterprises, Inc. in Leesburg, Fla. He can be reached at www.mikeholt.com.

About the Author

Mike Holt

Mike Holt is the owner of Mike Holt Enterprises (www.MikeHolt.com), one of the largest electrical publishers in the United States. He earned a master's degree in the Business Administration Program (MBA) from the University of Miami. He earned his reputation as a National Electrical Code (NEC) expert by working his way up through the electrical trade. Formally a construction editor for two different trade publications, Mike started his career as an apprentice electrician and eventually became a master electrician, an electrical inspector, a contractor, and an educator. Mike has taught more than 1,000 classes on 30 different electrical-related subjects — ranging from alarm installations to exam preparation and voltage drop calculations. He continues to produce seminars, videos, books, and online training for the trade as well as contribute monthly Code content to EC&M magazine.

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