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    Re: Big oops ... need suggestions

    The poll is now closed. Here are the results:
    Consider a simple on/off toggle switch that is located in a bedroom. That switch operates a light outside the bedroom. The circuit comprises no other loads and no other switches.

    Question: Do you believe that article 210.12(B) of the NEC requires this circuit to have AFCI protection?
    • Total number of responses: 133
    • Those responding YES: 33 (25%)
    • Those responding NO: 100 (75%)
    Last edited by George Stolz; 08-27-07, 06:47 AM. Reason: To clear formatting tags created by updating of the forum software. The content is unchanged.
    Charles E. Beck, P.E., Seattle
    Comments based on 2017 NEC unless otherwise noted.

    Comment


      Re: Big oops ... need suggestions

      This thread is now open, and will remain open until Friday November 5. Each member is invited to express your views on any issue that has been discussed in this thread.

      Remember the rules. You can post one time only, and you may not edit your post to respond or comment on any post made by any other member. If you do so, your post will be deleted.

      I suggest that you do not try to wait until the end to get the "last word in." I am invoking my Moderator's priviledge to make the last post, before closing this thread. But that post will consist of nothing more than a "good night and good luck," along with a statement of fact regarding the total number of posts that have been made to this thread.

      Let the statements of viewpoints begin.
      Charles E. Beck, P.E., Seattle
      Comments based on 2017 NEC unless otherwise noted.

      Comment


        Re: Big oops ... need suggestions

        Ok, I'll start.

        This whole debate is built on a foundation of sand. The AFCI is a dubious and unproven technology at best, with unknown effectiveness in extinguishing arcing faults.

        Accurate statistics for fires started by premises wiring cannot be found, but I suspect that fires truly caused by premises wiring are quite rare. I do not consider an outlet box containing a switch to be a likely ignition source.

        As far as the debate goes, a switch is not an outlet. It interrupts the path of current. It does not utilize current. I can't plug into a switch. AFCI not required.

        Comment


          Re: Big oops ... need suggestions

          The key to this issue are the words "current is taken to supply utilization equipment" in the Article 100 definition of outlet. Just because current is taken at the switch to control the utilization equipment does not mean that it is taken to supply utilization equipment at that same point. If the current it taken to control, but not supply the equipment, that point on the system is not an outlet. The outlet only exists where the current it taken to supply the equipment, not where it is taken to control that same equipment. Therefore the branch circuit that supplies loads in locations other than a dwelling unit bedroom, with a switch or other controller in that bedroom, is not required to have AFCI protection by the 2005 NEC.

          I hope that someone who has participated in this debate has submitted a proposal to clear up this issue. No matter what proposal would be submitted, the CMP would have to comment and that would put this issue to rest. Online proposals can still be submitted until 5 PM on Friday, November 4, 2005

          I would like to thank all that have taken part in this epic debate, as for the most part it has been kept on track and civil.

          Charlie, thanks for the great job in managing this thread.
          Don, Illinois
          (All code citations are 2017 unless otherwise noted)

          Comment


            Re: Big oops ... need suggestions

            Here is an e-mail I got from Raleigh a while back concerning the Arc-Fault protection of switches. My question was two parts, one with the neutral and the other with out.
            Mike, first we have to look at 210.12.(B) which states that the arch-fault protection is for outlets. Then we must look at the definitions of outlets in Article 100, which states, a point on the wiring system at which current is taken to supply utilization equipment. A receptacle would be, and a lighting outlet would also a smoke detector is a place where the current is utilized. But at a switch the current is not utilized in the room so in either case the switch would not be required to be on arch-fault protection.
            I hope this will answer your questions.
            Thanks
            Mitchell Bryant
            Chief Asst. Electrical Inspector
            322 Chapanoke Rd. Suite 200
            Raleigh, NC 27603-3400
            on the system where current is taken to supply. I can not see where it says current is being taken from the system. Should I enter a junction box and take current form that box to supply current to a box that I will hang a light and from and from the same junction box I leave to hit a receptacle. I just made that junction box an outlet as described by the sections in the code and the definition of outlet.

            This is how I was taught the code way back when. I can see the logic and understand the point that my instructor was making. I also under stand the logic in not requiring the electrical contractor to supply an Arc-Fault breaker for one switch although I foresee this coming.

            My final statement is that it saddens my heart that a thread that would have made the 1000 post mark was so abruptly shut down. There was much left that could be learned from the debate.
            It is only when we close our minds that we stop learning. Thank you Charlie B and Al for the knowledge that I gained from your debate and the points both of you made. I now look at Premise wiring in a different way.
            Mike Whitt
            God answers Knee-Mail.

            Comment


              Re: Big oops ... need suggestions

              I tend to view the term "premises wiring" as a one way street. From the Utility (which is free from the NEC), the premises wiring begins (and is governed by the NEC), then ends at the outlet(s), and thereafter the NEC treads very lightly. The definition of "premises wiring" and most of the NEC support this belief.

              The concept that a switch does not fall under "premises wiring" and therefore is an outlet contradicts this principle. I admit, I haven't read this thread through and haven't seen the arguments on both sides. My first attempt resulted in irrational anger, which doesn't help anybody.

              My analogy: Premises wiring is the national interstate system. The conductors are roads. Northbound are ungrounded, Southbound are grounded. Whatever.

              A switch is an intentional break in an ungrounded conductor. It is not an outlet, pure and simple. It's a speed bump on the road to the load, not the exit ramp to the load. To the electrons flowing in the circuit, the switch is the "Exit, 1 mile" sign.

              Would it make sense to exit the freeway only to get dumped back on the road for another mile? That essentially what is said when you say a "switch is an outlet."

              I saw a post stating that if a neutral is present, it's an outlet, but if there isn't, it's not. Can you present one case where this idea is supported by the NEC? The only item I know of that remotely resembles this idea is 404.3-ish (book's in the truck) where it states that neutrals don't have to run with switching loops. Nowhere is the word "outlet" used, if memory serves.

              Point to one reference - one reference to the term "switch outlets" in the NEC. If such an animal exists, why is it not defined? It would be such a tremendous omission that has led 75% of electricians polled believe it to be fiction. Quite an omission, considering a house can have roughly half it's wiring devices as switches.

              Some of the best and brightest members of this forum and of the industry at large do too. The second to last time I checked in, someone had posted a statement from Mark Ode confirming the majority opinion.

              In conclusion, it's commendable to look at the NEC from all sides, poke it, prod it, and look at it from different perspectives. Argue both sides of an issue to gain full respect for it. But believing your own b.s. is a perilous road to madness. If you can't come back, you'll only take others with you.

              As your mother once said, "Your face is going to freeze like that!" Only in this case, it's mental perception, not looking crosseyed.

              If y'all had fun, that what counts.

              Don, I hope you write something, I haven't the time.

              Comment


                Re: Big oops ... need suggestions

                My belief is based on the idea that AFCI protection was originally introduced to address fires caused by arcing faults in power cords and other parts of appliances, lighting fixtures, power strips, etc., not in-wall wiring and devices.

                I have been involved with several fires caused by overvoltages introduced into homes caused by primary-to-secondary faults or lightning. In each case, plugged-in devices and wiring were where the damage occured, not in the outlets.

                It seems logical that, if the premises wiring and devices were the issue, either all circuits, or at least those adjacent to bedrooms (i.e., wiring within the walls) would have the requirement, not just those with bedroom openings.

                If every electrical device, equipment, load, etc. were the intended target, then why wouldn't the NEC say that baseboard heaters, their thermostats, 240v A/C receptacles, etc., require AFCI protectiopn, and not just...

                "...125-volt, single-phase, 15- and 20-ampere outlets installed in dwelling unit bedrooms..."?

                Plus, why only dwelling unit bedrooms, and not hotels and motels, dormatories, apartments, overnight summer camps, and maybe even hospitals? They all certainly have plenty of outlet use, especially dorm rooms at colleges!

                Another kinda-related example: suppose someone installs a whole-house exhaust fan that, for some reason, is placed in a bedroom ceiling instead of a hallway? Must the fan be AFCI protected? What about its switch or timer?

                Please note: the above questions are purely rhetorical, and not meant to elicit a response.

                "That's all I have to say about that." - Forrest Gump
                Master Electrician
                Electrical Contractor
                Richmond, VA

                Comment


                  Re: Big oops ... need suggestions

                  First I'll offer a philosophical statement:
                  I have been as guilty as anyone in prolonging this thread, and more so than most. But I have had a justification for so doing, at least to my own way of thinking.

                  I welcome differences in opinion. I welcome discussions about the differences. I welcome submission of reasons, arguments, code citations, and other evidence in support of opinions. Finally, I welcome anyone to state and to support their opinion, even if it is contrary to my own.

                  But I do not welcome what I would call "the inadvertent misleading of the younger or less experienced members of our profession," when I believe the information being provided, however well intended, is just plain wrong.

                  I believe that the viewpoint expressed in this debate as being contrary to my own viewpoint is just plain wrong. I did not choose to stand idly by and let someone "pronounce the truth" as though it were obviously true, or as if it had been proven true, when I am certain that it is not true, and when it may lead members of our profession to incorrect conclusions.

                  I fully expect anyone who believes that I have said something untrue, or who believes I have misinterpreted the code, to step forward and say something. I readily invite you to do so. That has certainly happened in this thread, and I thank everyone who has made a contribution.

                  I would have been glad to have this thread settle for a "let's agree to disagree" ending. But the thread never headed down or even approached such a path. So another way was needed to bring it to an end. I hope the membership will forgive the out-of-the-ordinary way that I chose to bring about that end.
                  And here's a statement on the topic of safety:
                  I have never seen this particular "AFCI or not" question as a safety issue. If you want to install an AFCI device to protect a circuit that has a switch in a bedroom and a light outside the bedroom, then it is not unsafe to do so. At worst, your cost estimate will be higher than that of your competitor, and you will lose the job.
                  Now to my summary of my viewpoint.

                  I am a schooled and skilled Technical Writer, more so than is commonly seen in members of the engineering community. One of the skills of a Technical Writer is the ability to take a long sentence (and long sentences, such as the one I am writing now, are pure evil incarnate), and replace it with a series of shorter sentences that convey, as nearly as possible, the same meaning. The Technical Writer is free to rearrange the order of the thoughts expressed in the original sentence, if by doing so the original meaning comes through in a clearer way. You have to know our language well, in order to keep the "shorter, replacement sentences" true to the original "too-long sentence." I do know our language well; I am confident in what follows.

                  Here, then, is my interpretation of the definition of "Premises Wiring (System)," written in shorter sentences, and offered for the purpose of rendering clear that which (apparently) was not clear. This is not intended to be code language, nor even a translation into common conversational English. Rather, it is intended as a translation from code language to the language of the Technical Writer's Profession.
                  </font>
                  • <font size="2" face="Verdana, Helvetica, sans-serif">A Premises Wiring System consists of wiring and a set of things that are associated with wiring.</font>
                  • <font size="2" face="Verdana, Helvetica, sans-serif">The wiring includes both interior and exterior wiring.</font>
                  • <font size="2" face="Verdana, Helvetica, sans-serif">The wiring includes power wiring, lighting wiring, control wiring, and signal circuit wiring.</font>
                  • <font size="2" face="Verdana, Helvetica, sans-serif">The wiring includes both permanently installed and temporary wiring.</font>
                  • <font size="2" face="Verdana, Helvetica, sans-serif">The wiring that is part of the Premises Wiring System begins at the service point or other source of power.</font>
                  • <font size="2" face="Verdana, Helvetica, sans-serif">The "other source of power" could be a battery or a solar photovoltaic system. It could also be the windings of a generator, transformer, or converter.</font>
                  • <font size="2" face="Verdana, Helvetica, sans-serif">The wiring that is part of the Premises Wiring System ends at each individual outlet.</font>
                  • <font size="2" face="Verdana, Helvetica, sans-serif">The Premises Wiring System includes all the hardware, fittings, and wiring devices that are associated with the wiring that is described above.</font>
                  • <font size="2" face="Verdana, Helvetica, sans-serif">The wiring that is part of the Premises Wiring System does not include wiring that is internal to appliances, luminaires, motors, controllers, motor control centers, or similar equipment.</font>
                  <font size="2" face="Verdana, Helvetica, sans-serif">What I conclude from this definition is that a switch that controls a luminaire is itself part of the premises wiring system. Current passing through the switch never leaves (i.e., is never "taken" from) the premises wiring system.

                  Finally, here is my interpretation of the Article 100 definition of "outlet." If current leaves the Premises Wiring System at a given point, and if the very next place it goes is anywhere other than a piece of utilization equipment, then that "given point" is not, by definition, an "outlet." Saying that current is "taken" to control utilization equipment is not the same as saying that current is "taken" to supply utilization equipment. The definition uses the word "supply," not the word "control." If the utilization equipment is not taking current at that specific point, then that specific point is not an "outlet." This does not happen at a simple ("no frills") on/off toggle switch. The point at which the utilization equipment (i.e., luminaire) takes the current is within the outlet box to which the luminaire is mounted, not at the outlet box that houses the switch. Those are two different points, and only one of them is an "outlet."

                  Current is not taken from the premises wiring system at the switch, as the switch is part of that system. Therefore, there is no "outlet" on, in, or near the switch. No outlet, no AFCI required.
                  Charles E. Beck, P.E., Seattle
                  Comments based on 2017 NEC unless otherwise noted.

                  Comment


                    Re: Big oops ... need suggestions

                    There is not even a glimmer of hope that I could come up with anything remotely intelligent after Charlie. Well done sir!
                    There are two kinds of people - those smart enough to know they donít know, and those dumb enough to insist they do.-----Margery Eagan

                    Open shop since 1988

                    Comment


                      Re: Big oops ... need suggestions

                      Charlie is a tough act to follow ,but here goes.

                      The language in 210 .12( b ) tells us the answer it tell us that , All 120-volt, single phase, 15- and 20-ampere branch circuits supplying outlets installed in dwelling unit bedrooms shall be protected by a listed arc-fault circuit interrupter, combination type installed to provide protection of the branch circuit.

                      The use of the word "outlet" is the key .

                      A general use snap switch is a device . It is not listed to be installed at the point of outlet.

                      It does not require electric energy to function.

                      It does not supply ,
                      It interrupts the flow of electricity to the outlet and is rated to do so .
                      By using the word " outlet" they have defined that, what is to be protected is the point of supply to the utilization equipment.

                      The switch does not utilize electric energy therefore no outlet at the switch.
                      Thanks for reading and I learned a good deal by taking part,
                      so... thanks for posting as well.

                      Comment


                        Re: Big oops ... need suggestions

                        Have been following this thread a little and did not see any discussion of lighted switches. Otherwise I would say that current is not taken from the premesis wiring system at a switch, it is just controlled there.

                        Mark

                        Comment


                          Re: Big oops ... need suggestions

                          I have had one or more requests that I extend the deadline, by members who cannot yet take the time to post their final statements. I'll keep this thread open over the weekend.
                          Charles E. Beck, P.E., Seattle
                          Comments based on 2017 NEC unless otherwise noted.

                          Comment


                            Re: Big oops ... need suggestions

                            If you really want to get technical about the whole situation, a light switch can utilize current. Maybe not right away, but it may eventually. In my bedroom, I have a dimmer switch. What is in most dimmer switches? An enternal lighted handle. My point is that, it can be a power source. It may not be not, but it can when miss homeowner puts a dinner on. Can this be enough to cause an arcing condition. Yes. Therefore, It must be considered an outlet and yes the fan must be ARc fault protected. Ok, I will admit. I could not find anything new to discuss so Im digging very very deep!!!
                            Chris Hill, EE,ME,GA-CR
                            Power Factor Correction

                            Comment


                              Re: Big oops ... need suggestions

                              210.12(B) Dwelling Unit Bedrooms. All branch circuits that supply 125-volt, single-phase, 15- and 20-ampere outlets installed in dwelling unit bedrooms shall be protected by an arc-fault circuit interrupter listed to provide protection of the entire branch circuit.

                              Call me crazy but it states all "circuits" must be protected not all devices. If I change a receptacle should I change breaker? Heaven forbid.

                              Comment


                                Re: Big oops ... need suggestions

                                From the Author: This has been a very interesting discussion. Thanks to everyone that took part in this and several other threads that discuss the issues raised by applying the requirements of the 2005 NEC 210.12 to real world wiring. I have learned a lot from all who participated.

                                The background that I bring with me to this discussion is, in part, informed by being a one person electrical contracting business owner, by being a working (hands on the tools) Minnesota Master Electrician, by holding a Bachelor of Science in Electrical Engineering, and by text editing for the past eighteen years (resulting in my position as Senior Technical Electrical Consultant for several books and two ongoing monthly magazines).






                                Introduction.

                                My motivation in articulating what I have come to understand the meaning of Outlet, and Premises Wiring (System), to be is simple: we need to talk about it. The hardware one may install in dwelling bedroom switch locations, occasionally, is obviously utilization equipment in its own right, or, has obvious components that, by themselves, would be utilization equipment. When this hardware is discussed in a community of peers, diverse opinions are expressed, some cogently, some dogmatically, some with deliberate obfuscation. The status quo is that, no matter what goes on in the hardware that is used as a switch, "The hardware is a switch, not an outlet." This has been stated in many ways. The contradiction of the hardware in my hand that, in part, is a switch, has been impossible for me to ignore. I decided to speak out. Using the language of the NEC itself, I have come to defend as a cohesive whole an interpretation of:</font>
                                • <font size="2" face="Verdana, Helvetica, sans-serif">210.12 Arc-Fault Circuit-Interrupter Protection</font>
                                • <font size="2" face="Verdana, Helvetica, sans-serif">Art. 100 Outlet</font>
                                • <font size="2" face="Verdana, Helvetica, sans-serif">Art. 100 Controller</font>
                                • <font size="2" face="Verdana, Helvetica, sans-serif">Art. 100 Premises Wiring (System)</font>
                                • <font size="2" face="Verdana, Helvetica, sans-serif">404.14 Rating and Use of Snap Switches.</font>
                                <font size="2" face="Verdana, Helvetica, sans-serif">
                                My comments below are specifically bearing in mind a bedroom switch on a 15 or 20 Amp 120 Volt branch circuit controlling an outlet outside the bedroom. 2002 and 2005 NEC 210.12 is pretty straight forward and unambiguous in its requirement that all 15 and 20 Amp 120 Volt branch circuits supplying outlets in bedrooms must have Arc-Fault Circuit-Interrupters (AFCIs). Applying 210.12 requires an agreement on the definition of the term "outlet".

                                I contend that the definition of Premises Wiring (System) tells us that the current in a switch is not in the Premises Wiring (System), and, therefore, an outlet occurs at the point on a switch where the switch wiring becomes internal to the switch.

                                Definition of Outlet.

                                The earliest definition of outlet, that I have in NEC books in my possession, is:
                                1933 NEC. Part 1. Chapter 1. Definitions.
                                Outlet.
                                A point on the wiring system at which current is taken to supply fixtures, lamps, heaters, motors, and current-consuming equipment generally.
                                To this day, the core phrase is unaltered. The core phrase is "A point on the wiring system at which current is taken to supply. . ." Current. Not power, or energy, or voltage. This current is specifically current taken to supply utilization equipment. The electrical properties of the utilization equipment along with the voltage impressed on the utilization equipment determines the current that flows from the "outlet" to the utilization equipment.

                                </font>
                                • <font size="2" face="Verdana, Helvetica, sans-serif">The "outlet" does not utilize electrical energy. Current flows, or does not flow, in the outlet dependant upon the utilization equipment drawing the current.</font>
                                • <font size="2" face="Verdana, Helvetica, sans-serif">The "outlet", itself, is a spot, a point, along the current path at which the current of the utilization equipment passes. Current passes from one side of this spot on the current path to the other side of the spot.</font>
                                • <font size="2" face="Verdana, Helvetica, sans-serif">The definition of outlet doesn't concern itself with whether the same amount of current, or any amount of current, returns from the utilization equipment at, or near, the spot on the current path that the current was taken.</font>
                                • <font size="2" face="Verdana, Helvetica, sans-serif">The definition of outlet doesn't specify the physical location of the utilization equipment relative to the location of the point on the wiring system at which current is taken.</font>
                                • <font size="2" face="Verdana, Helvetica, sans-serif">The definition of outlet doesn't prohibit two or more outlets being in series with each other along the current path.</font>
                                • <font size="2" face="Verdana, Helvetica, sans-serif">The definition of outlet doesn't prohibit the current taken to supply utilization equipment from re-entering the wiring system and from being taken again at another point on the wiring system.</font>
                                <font size="2" face="Verdana, Helvetica, sans-serif">
                                The Problem.

                                The definition of outlet is a simple and uncomplicated definition, born in the early 1900s. The definition of outlet applies to AC and DC systems, single circuits, multiwire circuits, single phase AC and multiphase AC.

                                Over many decades, electricians have come to believe that "outlets utilize energy" and that "switches control energy, they don't utilize energy, so switches are not outlets". These two beliefs have risen to the level of intuitively self evident truth, in spite of the definition of Outlet clearly stating that an outlet itself is only current passing a point, that utilizing energy is not what the outlet itself does. Until the advent of the 2002 & 2005 NEC Arc Fault Circuit Interrupter requirements, the inaccuracy of these two beliefs had only academic interest. Today, these two inaccurate beliefs are adversely affecting new wiring installations.

                                Definition of Premises Wiring (System).
                                2005 NEC Article 100 Definitions.
                                Premises Wiring (System).
                                That interior and exterior wiring, including power, lighting, control, and signal circuit wiring together with all their associated hardware, fittings, and wiring devices, both permanently and temporarily installed, that extends from the service point or source of power, such as a battery, a solar photovoltaic system, or a generator, transformer, or converter windings, to the outlet(s). Such wiring does not include wiring internal to appliances, luminaires (fixtures), motors, controllers, motor control centers, and similar equipment.
                                The Definition of Premises Wiring (System) was added to the NEC in 1978. The definition is in two parts.

                                The core of the first part is: "Premises Wiring (System). Wiring extends from point or source to outlet."

                                The core of the second part is: "Premises Wiring (System). Wiring does not include wiring."

                                The first part of the definition of Premises Wiring (System) begins "That interior and exterior wiring,. . ." The one word wiring is the subject of the first part of the definition.

                                "Premises Wiring (System)" (is) "That interior and exterior wiring,"



                                The Venn diagram, above, I understand from the language of Premises Wiring (System) is very simple.

                                The single red rectangle bounds everything that is Premises Wiring (System).

                                The single red rectangle is divided horizontally into two smaller red bordered rectangles: "Interior Wiring" and "Exterior Wiring".

                                The color added divides the contents of the same large rectangle (the Premises Wiring (System) into two parts. The orange is as labeled in the separate orange swatch, and the blue is as labeled in its separate color swatch.

                                When the second sentence of "Premises Wiring (System)" is applied, one puts a small circle, or whatever shape, representing an item whose internal wiring is not part of the wiring system, into the appropriate relationship to the four overlapping areas.

                                "Wiring" in context.

                                The context for the word wiring can be read to mean "The wiring an electrician installs for a customer." The context of "wiring" is broad and, in addition to the metal of the wire, includes all the parts that make the wiring a complete system from the source or supply to the outlet. These parts include , and are not limited to, insulation, sheath or raceway, connectors, enclosures, mounting and/or support systems, devices, fittings, etc.

                                The definition of Premises Wiring (System) continues, after "That interior and exterior wiring," with one unbroken phrase comprised of two clauses: "including power, lighting, control, and signal circuit wiring together with all their associated hardware, fittings, and wiring devices,". This unbroken phrase is making clear that the metal of the wire is not all that is meant by "wiring" even when considering power wiring, lighting wiring, control wiring and signal circuit wiring. This unbroken phrase says, among other things, that "wiring devices" are a part of "interior and exterior wiring".

                                "Wiring" appears in the NEC over 750 times in varied contexts.

                                The dictionary defines "wiring" as "a system of connected wires."

                                The dictionary defines "wire" as "a pliable thread or slender rod of metal." Note the lack of "conductive" in the dictionary definition. Any electrician can think of wire that is not pliable, nor a thread, nor slender, nor a rod. Certainly, the meaning of "wiring", as used in the definition of Premises Wiring (System) must include electrical conductivity and a more varied physical form, so, another definition than that of the common dictionary must be referenced.

                                My copy of the IEEE Standard Dictionary of Electrical and Electronic Terms does not include "wiring".

                                My copy of the IEEE Standard Dictionary of Electrical and Electronic Terms does include "wire" and it makes an interesting statement:
                                If a wire is covered with insulation, it is properly called an insulated wire: while primarily the term wire refers to the metal, nevertheless when the context shows that the wire is insulated, the term wire will be understood to include the insulation.
                                Looking at the context of "Interior and exterior wiring," in the definition of Premises Wiring (System), I find "wiring" to be the completed assembly I, as an electrician, leave at an occupancy at the end of my job. If my job was to do a temporary or permanent install, the completed assembly is the "wiring".

                                The point of this summary is to show that a wiring device, as used in the definition of Premises Wiring (System), is part of "That interior and exterior wiring,". The second part of the definition of Premises Wiring (System) invokes the subject of the first part ("Interior and exterior wiring") and lists wiring that is not included. The internal wiring in controllers are called out as not part of "such wiring".

                                Snap Switch as Controller

                                The common snap switch, as referenced by 2005 NEC 404.14, is used as a controller. Because a current traveling inside the snap switch is not traveling in part of the Premises Wiring (System), the current has to be taken from the Premises Wiring (System). Because the snap switch only carries and controls the current, the current is determined by the utilization equipment. The current in the snap switch is the current taken by the utilization equipment, it is the current supplying the utilization equipment.

                                The current taken from the Premises Wiring (System) at the point that the current goes internal to the controller is the current taken by the utilization equipment for its supply in utilizing electric energy.

                                Conclusion

                                Hence, an outlet occurs at a switch used as controller of an outlet.

                                A switch located in a bedroom and controlling an outlet outside the bedroom must be provided AFCI protection.

                                This is a general statement that only has application in wiring installations governed by the 2002 and 2005 NEC 210.12.

                                But a greater good is served by clarifying what an outlet, as defined, actually is. Electricians should not be misled into believing that a box is an outlet, that an outlet utilizes energy, that a switch cannot have an outlet inside it because a switch only controls energy. While most electricians believe these statements to be self evident truth, that doesn't make the statements correct.

                                Today, new installations of a switch inside a bedroom, controlling outlet(s) outside the bedroom, may be supplied by a non-AFCI protected overcurrent protective device. In most jurisdictions, the Authority Having Jurisdiction will approve the installation. All such non-AFCI installations will then operate, and, over the passage of time, will suffer a statistically guaranteed minimum number of failures. Some of these failures will result in property loss, injury and potentially death. Subsequent liability litigation can easily demonstrate how poorly electricians understand the meaning of outlet, and can easily demonstrate an outlet occurs in the switch inside the bedroom, as I have, and that the AFCI, had it been installed, would have prevented the loss.

                                It only takes one cup of coffee in one lap to result in litigation that changes what had been industry wide accepted practice.

                                It is time to pay attention to the confusion about what an outlet is, and teach a consistent perspective, based on the actual language of the NEC. The existing confusion is affecting installations of wiring systems adversely.
                                Another Al in Minnesota

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