Switch boxes installed in noncombustible material such as gypsum are allowed to be flush or up to a 6 mm (1/4 in.) setback.Īll switches and circuit breakers that are used as switches must be located so they can be operated from a readily accessible place. Where these switch or circuit breaker handles are operated vertically rather than rotationally or horizontally, the “up” position of the handle must be in the “on” position (see NEC 404.7). General-use and motor-circuit switches and circuit breakers, where mounted in an enclosure, must clearly indicate whether they are in the open “off” or closed “on” position.
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Energized parts are required to be protected by a barrier to prevent operator exposure when making manual adjustments or switching.Ī single-throw knife switch must be connected so the switch blades are not energized when the switch is in the open “off” position. Time switches, flashers, and similar devices are required to be of the enclosed type or must be mounted in cabinets or boxes or equipment enclosures. A flush-mounted switch or circuit breaker in a damp or wet location must be equipped with a weatherproof cover. Where surface-mounted switches are installed in any damp or wet location, such as outside of a dwelling, a switch or circuit breaker is required to be enclosed in a weatherproof enclosure or cabinet. Switches such as the single-pole, three-way, four-way, double-pole, and enclosed knife switches in the fused and unfused types are just a few examples of switches installed in dwellings. Many different types of switches are installed in one- and two-family dwellings. General Provisions for and Facts Concerning Switches Some of the more common types of switch are described in table 1.
Switches are typically referred to by the number of possible switch positions per pole, such as a single-throw or double-throw switch. Switches are often distinguished by the number of poles and referred to as single-pole or double-pole switches, and so forth. Switches frequently are composed of two or more single-circuit elements, known as poles, all operating simultaneously or in a predetermined sequence by the same mechanism. Basically, a snap switch consists of two or more contacts mounted on an insulating assembly and arranged so that they can be moved into and out of contact with each other by a suitable operating mechanism. In this article, let’s take a look at switches and their NEC requirements.Ī switch is a device used to open or close an electric circuit or to change the connection of a circuit. Switches are just not very sexy, but they are everywhere, especially in dwelling units, and the NE Chas a lot to say about these sometimes inconspicuous devices. After all, that switch has worked all of the 18,235 times I’ve flipped it on before! Only after we check all possible failure points do we even consider that the switch itself might have gone bad. If the connections are OK, it must be a loose wire in the receptacle outlet just ahead of the switch in the branch circuit. If the light bulb is OK, we might even check the connections to the luminaire while we’re up on the ladder. When you flip a switch to the “ON” position and the luminaire does not illuminate, what’s the first thing you do? The first thing we check is the light bulb. Switches on the other hand, are often over-looked unless something is not working. Receptacle outlets are the “face” of electrical devices, and luminaires are often grand and elegant in design and attract lots of attention.
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Question: What has a couple of poles and says “NO” when turned upside down?Īnswer:A single-pole switch! Weren’t we all taught as apprentice electricians and helpers that if you install a single-pole switch upside down, rather than say “ON” it will say “NO” to you! We perhaps take switches for granted.
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