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IAEI News provides educational forums, updates on electrical codes and reports of innovative research to facilitate the development and enforcement of practices designed to drive efficiency and compliance with the highest standards of product development and safety—for the public as well as for electrical personnel. The magazine reaches authorities with power of product specification, approval and acceptance. Published six times a year by the International Association of Electrical Inspectors.

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NEC-2011, Call for Proposals

Posted By Chuck Mello, Saturday, March 01, 2008
Updated: Friday, February 08, 2013

The NEC-2008 has been complete for only a few short months, six since the adoption by NFPA, and four since the very first printing. The CD version just came out and the handbook is due sometime in late January or early February. As this is being written, there is a lot of activity in many areas of the United States with the adoption process by jurisdictions. Adoption in some areas will not be completed for one or more years.

Wow, now that we have the new Code out, can we take a rest? Unfortunately, No!

For those that have seen the IAEI Analysis or have reviewed the overall changes to the NEC, what do you think? Did everything get fixed, or is there still more to be done? I believe most of us will agree there is more to be done.

The IAEI has two members on each of the code-making panels and the Technical Correlating Committee. Even though we have this representation, we did not fully participate to the extent we could have and should have in the 2008 code-making process. One big benefit for all IAEI members is being able to be involved in the making of good code. What we did not do for the NEC-2008 cycle was to make many proposals and comments to clarify and fix the things that the membership, individuals and groups, see needing to be revised. One only needs to attend a local chapter or division meeting and listen for a short time to a Code discussion to know there are many areas in the NEC that can be improved to be clearer, more enforceable and to be "good Code.”

So why are we talking now about proposals? We have three years to the next one, right? The NEC is on a three-year schedule and so just as one NEC comes out, the process of change starts up right away. The schedule set by NFPA for NEC-2011 requires that all proposals must be at NFPA by 5 p.m. Eastern Time on November 7, 2008. That is just a few months away and that time will go by very quickly. It has been reported that several hundred proposals have already been submitted in this new cycle.

So again, why bring up proposals now to the IAEI membership and electrical industry in general? The answer is that now is the time to start the process on the local level so that proposals that are desired to have IAEI endorsement and to be submitted as IAEI proposals can be processed.

Under the NFPA rules, anyone can submit a proposal under his or her own name. The IAEI encourages that and does not restrict in any way anyone wishing to make such submissions.

If the individual also wishes to have IAEI endorsement, in addition to submitting the proposal himself or herself, then that person should work through the local chapter or division. The IAEI encourages the chapters and divisions to work cooperatively to develop good code proposals. These groups can discuss and refine the proposed language and be sure the technical substantiation is complete and solidly supports what is being proposed. Proposals may start with a voice of one, but they get stronger and gain power with support and input of the many. IAEI chapters and divisions can submit proposals as a group, but it must be under a person’s name (generally the chapter or division secretary) and not indicate that it is an IAEI organizational proposal.

You ask again, why worry about this now, there is lots of time? Many chapters and divisions have their annual business meeting in the spring and this is when the membership of the chapter or division needs to act on any proposals to move forward from the local organization. So now is when this beginning work needs to be done so proposals can be processed at these spring meetings. To help with this, the International Education Committee has developed a short PowerPoint training program for use by the chapters and divisions on Code proposal writing. This has been presented at several recent chapter or division meetings and has been well received. Check the IAEI website atwww.iaei.orgto download a copy for use. [Go to home page, check left-hand column under Get the Latest Information.]

The next step is at the section level. Based on policies set by each section, chapters and divisions, and in some cases individuals, can submit their proposals to the section for consideration. The Section Code and Standards Committee will complete a review and then make a recommendation to the membership at the section meetings in September and October of this year. The section needs to receive these proposals in time to meet two deadlines. One deadline is so the Section Codes and Standards Committee has the opportunity to review, meet, discuss, and provide a recommendation to the membership to vote on. Most of the sections have set dates in the July timeframe, so check with your section secretary to find out what the deadline is. The second deadline is for the IAEI International Codes and Standards Committee. This committee needs all the proposals that might become IAEI-endorsed proposals to be at the IAEI International Office on or before September 1, 2008. This date is set so the IO committee can review what is coming and then take final action once all the sections have completed their actions.

By the way, it is not the Codes and Standards Committee’s responsibility to write or revise proposals, its responsibility is to review what was submitted and make recommendations, based on the merit of the submission, to accept to go forward or to reject. It is also strongly encouraged that proposals not be written from the floor. It takes time, research and reflection to write good proposals and code writing from the floor rarely results in a good proposal. Again, the section, as a body, can make a submission, but it must be under a person’s name (again typically the secretary) and it cannot indicate it is an IAEI proposal.

The international president, in accordance with the International Bylaws, has appointed the members to the International Codes and Standards Committee. This committee will receive the proposals from the sections only. Proposals cannot be submitted by individuals to the International level. If the section acts favorably to forward proposals submitted to them for consideration as an IAEI organizational submission, then the committee will review the proposal in its entirety and if found acceptable will have it submitted by the executive director/CEO as an IAEI proposal.

Why does having it as an IAEI proposal matter? As stated before, the IAEI has two representatives on each panel and they will be instructed and are bound to be advocates for IAEI proposals as submitted by the international executive director/CEO. Having a voice at the panel ensures that the proposal gets considered and discussed fully by the panel.

At last year’s section meetings, each section board of directors and each section general membership was challenged to get involved in the 2011 Code cycle. The challenge that was issued from the international level was for each chapter and division to work at the local level and submit at least 10 proposals. Are you up for that challenge? Have you started yet? My chapter has, but still has much work to do. Now is the time to get involved with your local chapter or division. Being involved with the code change process is one of your membership benefits and getting involved now can make your job easier and more productive in the future.

Important Dates

July 2008
Most section proposals due.
Verify with your section what its deadline is.

September 1, 2008 5 p.m. CST
Proposals to be IAEI-endorsed due at International Office

November 7, 2008 5 p.m. EST
All proposals due at NFPA


Read more by Chuck Mello

Tags:  Featured  March-April 2008 

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Enthusiastic Membership

Posted By Tim McClintock, Saturday, March 01, 2008
Updated: Friday, February 08, 2013

IAEI has always played a strong leadership role in the electrical industry and continues to accomplish this goal by playing an active role in the code development process, providing first-class educational opportunities through seminars and publications, and by providing a medium through which inspectors, contractors, manufacturers, and any other parties interested in the electrical industry can discuss matters related to electrical safety.

Additional benefits of membership in IAEI include meeting and learning from electrical experts in the industry and having an unlimited knowledge base to draw from; staying current with the latest changes in the code; staying informed on the latest products and installation standards; having a voice in the code change process; and becoming active in the organization by attending and participating in local section, chapter, and division meetings.

Active participation and involvement in IAEI can have indirect benefits too. For example, staying current with code requirements could result in a more timely installation, as well as reduced number of return trips to go back and correct violations. Another indirect benefit is expanding your knowledge through IAEI that will help cultivate career advancement.

We have identified some of the major benefits, both direct and indirect. IAEI continues to be challenged with a decline in membership and we as members must recognize that the key to the success of this great organization is the strength of our membership. In order for IAEI to remain at the forefront of the electrical industry we must not only continue to bring new members in, we must show them the value of maintaining that membership.

The International Membership Committee held its annual meeting at international headquarters in November 2007 to review membership issues and formulate a plan to address the current state of membership in IAEI. It was the consensus of the committee that IAEI is at a crossroads, and we as members need to step up and continue to demonstrate why IAEI continues to be considered the keystone of the electrical industry.

Ensuring the sustainability of IAEI is accomplished through effective leadership and commitment. Anyone who joins an association has to be committed to the organization in order for it to grow and prosper. As an inspector or associate member, we can do this by attending our local meetings on a regular basis.

Membership chairs and membership committee members from all levels of the organization need to be committed to taking charge of the responsibilities that they have volunteered to perform.

The international office of IAEI has taken the first important step with this objective by providing training for membership chairs at the 2007 IAEI Annual Section Meetings. The international office presented a three-hour program, which included the introduction of IAEI New Member 12 Step Program and familiarizing membership chairs with the new "real time” membership database, which will provide membership chairs the ability to review membership status on a daily basis, as updated by the international office. Another part of the program included a contest, which gave contestants (membership chairs) the opportunity to demonstrate their knowledge of IAEI. Overall, the program proved to be very successful and each attendee left with the necessary tools to help better manage membership objectives.

The 12 Step Program is a joint effort between the international office and the local divisions and chapters to maintain a constant line of communication with a new member to keep them interested and involved with the organization. Some of the highlights of the 12 Step Program include providing the member with a list of available educational opportunities, including seminars and publications, information regarding submitting code proposals, and information about the international website, which includes access to products and services.

As mentioned earlier in this article, effective leadership plays a key role in the sustainability of IAEI. Each division and chapter provides many opportunities for members to become more active through participating on local committees.

Accepting a local committee appointment includes responsibilities the individual must be willing to carry out, which is the second part of the success of IAEI, commitment. Just as equally important, the division/chapter must be willing to provide the individual with the tools to succeed.

The role of the membership chair is a very instrumental part of the success of IAEI and that is why we would like to provide all membership chairs with some guidelines and recommendations for carrying out the success of your local division and chapter. The following suggestions will help foster the success of IAEI. It is also important to recognize that for this program to work, each membership chair must be willing to commit time and resources to carry out these tasks.

  • First, continue to encourage individuals associated with the electrical industry to become actively involved by joining IAEI.
  • Follow the 12 Step Program. The 12 Step Program ensures a constant open line of communication with a new member and shows them why IAEI remains the "keystone of the electrical industry.” The international office will soon have the 3-hour program available on CD and will provide each membership chair a copy thereof. When planning the program schedule for your next chapter meeting, make this program a priority on your schedule and reserve time to present this information to your membership chairs and/or local membership committee.
  • IAEI International provides an online membership database accessible to membership chairs. Set aside a time to review your membership database on a regular basis to review the status of your membership. The new database provides a wealth of information to help better manage membership. You can quickly review all current members or you can download different spreadsheets, such as current members, new members, and expired members. Checking this information regularly will enable you to take a proactive approach into the membership decline IAEI is faced with. Do you have expired members? How about new members? As the membership chair for your chapter or division, have you made contact with these new and/or expired members? This database is a valuable tool you can use to help manage your membership and we strongly encourage you to get actively involved reviewing it.
  • Attend local chapter and division meetings and always make membership an agenda item. Continually promote the benefits of membership in IAEI at your meetings.
  • Utilize your section membership chair as an information vehicle. We are here to help promote and improve membership. Having difficulty with your database? Not everyone is computer savvy. Contact your section membership chair and we will assist in everyway we can.
  • Establish a local membership committee. Assign mentors to follow up with current members to ensure they renew and stay current with the constantly evolving technology and code requirements.

A closer review of the last item is not a new concept. Mentoring is a process that has been around for many years. A mentor is a trusted friend, counselor or teacher, usually a more experienced person. Some professions have mentoring programs in which newcomers are paired with more experienced people in order to obtain good examples and advice as they advance, and schools sometimes have mentoring programs for new students or students who are having difficulties.

For those IAEI members, who have been around awhile, think back about when you first became a member of IAEI. I’m sure the majority can remember someone you looked up to or that individual approached you at your first meeting and welcomed you to the organization, encouraging you to get involved, ask questions and provided you with valuable insight.

In summary, the demographics of our organization are changing and we need to take the necessary steps to ensure the future of IAEI. A younger generation is now filling the workforce, which means we need to encourage this younger generation to become involved and join IAEI. Equally important, we need to provide effective leadership by committing to mentor current members, and to mentor this younger generation to show them why membership in IAEI is beneficial to the advancement of their career in the electrical industry.

Compiled by Membership Committee

Robert Kauer – Chairman – Eastern Section
R. Steve Jones – Southwestern Section
Leonard Devine – Southern Section
Tom Arbanas – Canadian Section
John Kendall – Northwestern Section
Tim McClintock – Western Section
Chuck Mello – Executive Committee Liaison
James Carpenter – Ex Officio (voting member)


Read more by Tim McClintock

Tags:  Featured  March-April 2008 

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How do I know if a meter socket was evaluated for a top or bottom feed or both?

Posted By Underwriters Laboratories, Saturday, March 01, 2008
Updated: Friday, February 08, 2013

Question: Meter socket

How do I know if a meter socket was evaluated for a top or bottom feed or both?

Answer

UL Lists meter sockets under the product category Meter Sockets (PJYZ) located on page 233 in the 2007 UL White Book. This information can also be located using UL’s Online Certification Directory atwww.ul.com/databaseby entering "PJYZ” at the UL Category Code Search. The Guide Information for meter sockets states: "Meter sockets are suitable for supply wiring to enter the enclosure from either the top or the bottom, unless the meter socket is marked ‘Overhead Feed Only’ or ‘Underground Feed Only,’ or the equivalent. The marking ‘Top Feed’ is considered equivalent to ‘Overhead Feed,’ and ‘Bottom Feed’ is considered equivalent to ‘Underground Feed.’”

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Tags:  March-April 2008  UL Question Corner 

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How do I know if a switchboard or panelboard is Listed for top or bottom feed or both?

Posted By Underwriters Laboratories, Saturday, March 01, 2008
Updated: Friday, February 08, 2013

Question: Switchboard

How do I know if a switchboard or panelboard is Listed for top or bottom feed or both?

Answer

Switchboards are Listed under the category Deadfront Switchboards (WEVZ), located on page 325 in the 2007 UL White Book. This information can also be located using UL’s Online Certification Directory at http://www.ul.com/database by entering "WEVZ” at the UL Category Code Search. The Deadfront Switchboard Marking Guide, located in Appendix A of the 2007 UL White Book, provides additional details regarding conduit entry/exit points. Specifically, on page 17 of the marking guide, under the heading "Conduit Entry,” the publication states, "UL evaluates switchboards to determine compliance for the clearance of conductors and conduit entering into the bottom of a switchboard, per NEC 408.5. Acceptability of other conduit entry/exit points can only be determined at the time of installation.” As also noted in this section of the marking guide, other entry points have been evaluated by UL "…if instructions and drawings showing the intended conduit or raceway locations are (1) supplied with the switchboard section or enclosure or (2) contained in the manufacturer’s catalog (identified by the catalog number or other designation that appears on the switchboard).

Panelboards, including "Enclosed Panelboards”, are Listed under the product category Panelboards (QEUY), located on page 251 in the 2007 UL White Book. This information can also be located using UL’s Online Certification Directory atwww.ul.com/databaseby entering "QEUY” at the UL Category Code Search. As noted in the guide information: "Only panelboards marked to indicate that they are for use in specific enclosures (identified by either catalog number or specific dimensional information) and panelboards labeled as "Enclosed Panelboards” have been investigated to determine that wiring space is adequate.” With respect to this statement, it should be noted that wire-bending space for Listed "Enclosed Panelboards” is evaluated to ensure compliance withNEC408.55. ThisCodesection defines the required top, bottom, and side wire-bending space for the enclosure of a panelboard. All enclosed panelboards, including those without a factory provided hole or knockout (or other provision for connection of a wiring system), would be required to comply with these basic requirements.

Conduit entry and exit points, such as holes, knockouts, or other provisions for connection of a wiring system, in panelboard enclosures have only been evaluated by UL where they are factory-supplied. Any field punched knockouts have to be evaluated by the AHJ in the field for suitability of wire bending space, maintenance of an environmental rating on the enclosure, spacings to live parts, etc. If a product is factory supplied with knockouts on the bottom or the side for a bottom or side entry and the installer punches a hole for conduits in the top, it is up to the AHJ to evaluate the suitability of that modification to the enclosure.

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Tags:  March-April 2008  UL Question Corner 

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How can these computer carts in hospital rooms be Listed when they conflict with the XBYS Guide Information?

Posted By Underwriters Laboratories, Saturday, March 01, 2008
Updated: Friday, February 08, 2013

Question: Relocatable power taps

I have seen computer carts in hospital rooms and exam areas that are provided with relocatable power taps. The Guide Information for Relocatable Power Taps (XBYS), states that "relocatable power taps have not been investigated and are not intended for use with general patient care areas or critical patient care areas of health care facilities as defined in Article 517 of ANSI/NFPA 70, National Electrical Code. How can these carts be Listed when they conflict with the XBYS Guide Information?

Answer

As indicated in the question, the Guide Information for Relocatable Power Taps (XBYS) located on page 343 of the 2007 UL White Book states that relocatable power taps are not intended for use in general or critical patient care areas of a hospital. The use is restricted from these patient care areas because UL cannot control what is connected to the power taps which could result in leakage current that would be in excess of what is permitted for patient care areas of hospitals. The Guide Information for XBYS can also be viewed atwww.ul.com/databaseon UL’s Online Certification Directory and enter XBYS at the Category Code Search.

UL does Classify complete system medical cart assemblies for use in hospitals under the product category "Medical Equipment (PIDF).” Guide Information for this product category can be found on UL’s Online Certification Directory atwww.ul.com/databaseand enter PIDF at the Category Code Search, and on page 228 in the 2007 UL White Book.

These carts are Classified as a complete medical system with the cart and medical equipment provided. This way the equipment connected to the power tap is controlled and the leakage current levels are determined to be below the permitted leakage current levels for patient care equipment in accordance with UL 60601-1, the Standard of Safety for Medical Electrical Equipment, Part 1: General Requirements for Safety.

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Tags:  March-April 2008  UL Question Corner 

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I have seen these power strips that pop up out of a counter in a kitchen, are these power strips Listed for use in kitchen counters?

Posted By Underwriters Laboratories, Saturday, March 01, 2008
Updated: Friday, February 08, 2013

Question: Power strips in kitchen

I have seen these power strips that pop up out of a counter in a kitchen, are these power strips Listed for use in kitchen counters? Are they intended to take the place of the small appliance branch circuit?

Answer

UL Lists power strips under the product category "Relocatable Power Taps (XBYS).” Guide Information for this product category can be found on UL’s Online Certification Directory atwww.ul.com/database, and on page 343 in the 2007 UL White Book.

There are some Listed relocatable power taps that have been investigated for use in kitchen counters. They are marked as suitable for use in kitchens and have been subjected to a spill test when the power tap is recessed into the counter with no attachment plugs inserted into the power tap. Relocatable power taps are not intended to be used as a substitute for fixed wiring and are not intended to replace the small appliance branch circuit as detailed inNEC210.52.

This information will be added to the Guide Information for Relocatable Power Taps (XBYS) in the 2008 UL White Book.

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Tags:  March-April 2008  UL Question Corner 

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A Look at IAEI’s Successes

Posted By James W. Carpenter, Saturday, March 01, 2008
Updated: Friday, February 08, 2013

Work needed on the roof, work needed on the walls and floor where the roof leaked, AC units getting old and needing to be replaced. Carpet wearing out, stairs needing refinished, plumbing problems in the bathrooms, more space needed. These are just some of the things that IAEI faces in the not-too-distant future with the headquarters building. Our building was ten years old when we moved to Richardson in 1992. Even though we were the first tenant, the physical structure is getting old.

To keep good staff, salaries and benefits must be kept competitive with the surrounding workforce. All this takes money just to stay at the existing level. Health insurance costs keep increasing, utilities costs increase, property taxes increase; everything costs more than they did five years ago.

All is not doom and gloom though. IAEI has an excellent staff that works extra hours sometimes to maintain the level of success we have come to enjoy and expect. IAEI’s financial condition is good. Our training books and seminars are considered the best in the land by many of our members and partners.

So, why the whining about costs? Let’s reflect back a few years ago when IAEI had to increase membership dues by 50 percent — from $60.00 to $90.00. That was a hard pill to swallow. Looking at the financial situation and future needs of IAEI and trying to avoid the big increases in membership dues, the International Board of Directors asked the Fiscal Affairs Committee to investigate the necessity and amount of a membership dues increase to become effective January 1, 2009, with a review of the necessity of dues increases every three years. The International Board of Directors also authorized a study of the physical facilities to determine the feasibility and possibility of remodeling, expanding, or moving to another location—whatever is found to be the best course of action, and what it will cost.

Let’s look at some of our successes. The Analysis of Changes, NEC-2008 has been a great success again this cycle. IAEI has partnered with NFPA to produce a two-disk DVD presentation on the Analysis, and is partnering with NFPA in presenting on-site seminars on the Analysis. IAEI is partnering with Underwriters Laboratories on several projects. One important project is the I am Safety Smart program. IAEI has joined a coalition made up of International Code Council (ICC), American Association of Code Enforcement (AACE), International Association of Fire Chiefs (IAFC), International Association of Plumbers and Mechanical Officials (IAPMO), International City/County Management Association (IC/CMA) and others to raise the profile of code officials and to inform the public about the importance of the role of code officials.

Many of IAEI’s programs help by bringing in funds to allow IAEI to provide programs and services for not only our members but for the public at large. One such program that has been mentioned earlier is the IAEI/UL I am Safety Smart program. I was afforded the opportunity to go to an elementary school in North Carolina just before the holiday break in December. I conducted the program for two second grade classes, two third grade classes, and a sixth grade class—a busy day with five different presentations. This was a highlight of my Christmas time in North Carolina. What a joy it was to be with those schoolchildren to impart electrical safety lessons to them. To watch their faces as we talked about Spike and being safety smart was worth more than any money that we spent putting together the materials. Check out some pictures and read some of the children’s comments later in this issue of the IAEI News. I encourage you to get your chapter or division involved in this worthwhile project. Some have said they are having a hard time getting into the schools. If you can find just one teacher to let you have some time with the class, then the message will spread and you may have more requests than you can handle. What better way to spread the IAEI message?

As you all probably know by now, Mike Johnston has moved on from IAEI and has taken an executive position with NECA. Mike has been a valuable asset to IAEI and he will be sorely missed. He has grown our Education Department from a one-man operation to what it is today. We all owe a great debt of gratitude to Mike, for his passion and love for IAEI and for what he has accomplished since his arrival in 1999. He has left us with big shoes to fill. He has set a high standard that IAEI must now continue. Continue we will. Congratulations, Mike, and best wishes on your new endeavor.

Read more by James W. Carpenter

Tags:  Editorial  March-April 2008 

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Understanding the Combination AFCI Expansion in NEC-2008

Posted By Bill Unseld, Tuesday, January 01, 2008
Updated: Friday, February 08, 2013

Arc-fault circuit interrupters (AFCIs) have become a familiar technology to electrical contractors during the past decade. The first branch-feeder AFCIs debuted in the late 1990s, and detected exclusively parallel arcs, or current that travels from one circuit conductor to another. They were followed more recently by combination AFCIs, which respond to both parallel and series arcs, the latter of which occurs when a single conductor is severed and electricity travels across the compromised point.

The 2005National Electrical Codemandated combination AFCIs for all 120-V, 15- and 20-A branch circuits that supply bedroom outlets in new homes starting January 1, 2008, which generally includes receptacle outlets, lighting outlets and smoke alarm outlets. The 2008 NEC expands the requirements for combination AFCIs beyond bedroom circuits to include other areas in a home, such as family rooms, dining rooms, living rooms, closets and hallways.

State and local electrical committees are beginning the process of adopting the 2008 NEC. Electrical contractors and inspectors have played a significant role in the development of the NEC and specifically in supporting the requirements for branch-circuit protection via AFCIs. They will once again play a significant role in supporting adoption of new 2008 NEC requirements, which includes AFCIs, tamper-resistant receptacles and increased conductor and conduit sizes used in direct sunlight on the roof. It is important for those contractors and inspectors playing a role in the adoption process to have a working knowledge about AFCIs in order to ask the right questions and provide informed answers when questions and concerns arise.

Photo 1. A series arc occurs when a single conductor is severed; for example, if one conductor on an appliance cord is cut or broken completely and current continues to flow in the slight gap between the two compromised points.


Photo 2. A parallel arc happens when current travels from one circuit conductor to another; for example, if the insulation is pierced by a nail or screw on the two current-carrying conductors at the same point and current travels between the conductors

AFCI basics

An AFCI circuit breaker protects branch-circuit wiring from arcing faults that could start an electrical fire. An arc fault occurs when current flows in an unintended path, and the heat generated at the point of the arc (up to 10,000° F) can set fire to insulation or wood framing. There are several ways an arc fault can occur, and they typically happen due to damage to wires or their insulation. Common arc-fault occurrences include:

  • Puncturing a wire with a nail, staple or a tool during installation or maintenance of the electrical system.
  • Damaging an electrical wire during tasks like hanging pictures or installing cabinets.
  • Damaging extension or appliance cords when furniture or an appliance has been positioned on the cord.
  • Advanced age of extension or appliance cords, which can over time experience worn or cracked insulation.

Any of those scenarios can result in a parallel or series arc. A parallel arc can occur if the insulation on an appliance cord is pierced by a nail or screw on the two current-carrying conductors at the same point, allowing current to travel between the conductors that are now slightly gapped. Conversely, a series arc can occur when a single conductor is severed; for example, if one conductor on a cord is cut or broken completely and current continues to flow in the slight gap between the two compromised points.

Unlike standard circuit breakers, all AFCIs use electronic processing technology built into the device itself to detect arcs. Electronics are used in various electronic-trip circuit breakers on the market today to protect circuits in large commercial buildings, so the premise is similar in residential applications. For example, a combination AFCI monitors a circuit for both dangerous and normal arcing conditions—some appliances, like a motor-driven vacuum cleaner, create arcs in order to operate correctly, which the AFCI will simply judge as a safe, operational arcing condition.

When a combination AFCI detects an arc, it employs its signal-processing capabilities to examine the arc’s electrical characteristics. If it deems the signal as a dangerous arc, it will open the circuit, thus removing the arcing condition, and possibly preventing a fire. Operational arcing criteria is based on known behaviors of electrical arcs, meaning the combination AFCI is programmed to detect the signal of a dangerous arc, compared to an operational arc. The device’s electronics will signal the breaker to open when the signature of a dangerous arc is determined to be present.

 


Photo 3. There are several ways an arc fault can occur, and they typically happen due to damaged wires or their insulation. Common arc-fault occurrences include accidentally puncturing a wire with a screw, as seen in this image.

 

Branch-feeder vs. combination AFCIs

The installation of combination AFCIs is identical to the branch-feeder AFCI and its cousin the ground-fault circuit interrupter (GFCI), which has been installed and inspected the same way for more than 30 years. Combination AFCIs require the neutral conductor of the circuit to terminate on the circuit breaker and then a neutral connection (generally a "pigtail”) must be connected to the neutral termination within a home’s load center. Keep in mind that each neutral connection from the circuit breaker must terminate in an individual termination and not be placed in a terminal with a ground wire or another neutral conductor in accordance with NEC 110.14(A) and NEC 408.41.

Proper installation of the branch circuit being protected by the combination AFCI is the most important aspect of ensuring not only an NEC-compliant installation but also a reliable one that does not require a follow-up visit because the AFCI found an issue with the installation. Here are a few items to check:

1. Make sure all connections are tightened properly to avoid creating an arcing condition.

2. Ensure the circuit’s neutral conductor is returned to the combination AFCI and the pigtail is connected to the neutral terminal on the panel. When the circuit neutral is mistakenly returned to the panel and not the AFCI, the AFCI will trip when a load is applied and the current reaches the ground-fault current threshold of the AFCI (typically 30–50 mA, though this value can vary from one manufacturer to the next) since no current is returning through the circuit breaker.

3. Make sure neutral conductors of different circuits are not connected together at any point in the branch circuit. When the neutrals of different branch circuits are connected, an AFCI will trip when a load is applied and the current differential is over the ground-fault current threshold (30–50 mA) of the AFCI. Due to a split in the return current path, the AFCI correctly "sees” this improper connection as a ground-fault.

4. Press the "Test” button on the front of a combination AFCI after the load center has been energized to ensure proper functioning of the AFCI. Many electrical inspectors also utilize a plug-in indicator/tripper in order to ascertain if the circuits required by the NEC are protected by the AFCI, but the AFCI’s "Test” button is the only acceptable method to verify the operation of the AFCI itself.


Photo 4. Combination AFCIs like the Square D (left) and Homeline devices from Schneider Electric use advanced digital signal processing technology to monitor a circuit for both dangerous and normal arcing conditions.

If you find an AFCI is tripping, consider troubleshooting by replacing it with a GFCI to understand if the AFCI is protecting the circuit due to a ground fault or an arcing fault. If the GFCI does not trip, then you may have an arcing condition being detected by the AFCI. The troubleshooting for a combination AFCI differs little from a branch-feeder AFCI. A few common places to look for installation issues before initiating an isolation effort include:

  1. Switches where the neutrals for different circuits have been connected.
  2. Receptacle outlets, lighting outlets or switches where the bare grounding conductor has made inadvertent contact with the neutral conductor or terminal.
  3. Luminaires, including recessed luminaires, where wire insulation may have been compromised during installation.

Also keep in mind that turning off a lighting outlet at a wall switch to make adjustments or installing a ceiling fan without turning off the AFCI may cause the AFCI to trip when the neutral and grounding wire come in contact where the circuit is feeding other loads. The perception is that after the fan is installed and the switch is turned on, the ceiling fan tripped the AFCI, when in fact the AFCI was tripped during installation. It is always best to de-energize the circuit before performing any type work on the circuit.

Eliminating non-compliant NEC installations is important not only to ensure a safe and reliable installation but also to reduce the need for a contractor to make a follow-up visit to a home to rectify the problem. Thus, verifying the installation is correct can help avoid unnecessary cost and labor strains later. That’s particularly important considering a contractor will likely be installing more combination AFCIs in the coming months and years.

It bears mentioning at this juncture that AFCI technology has matured to the point where combination devices are better programmed to discern a dangerous arc from a normal arc or even normal operating conditions, which also reduces the possibility of a nuisance trip occurring even if the installation is sound. Branch-feeder devices have been on the market for about eight years, and though combination AFCIs have been on the market for about the past year, the technology has been extensively field tested by facing day-to-day usage conditions in numerous homes.

In fact, the technology serves as a quality control means for electrical contractors. If a homeowner experiences an AFCI tripping, it could be that a mistake was made during the installation process, but it could also mean an appliance is malfunctioning and causing the breaker to trip. It’s particularly important to note that when an AFCI that trips due to an improper installation or malfunctioning appliance, it should not be considered a nuisance—it is protecting from the hazard it was designed to address.

The question of cost

Expansion of combination AFCI usage to other areas of a home in NEC-2008 is a natural progression from the NEC-2005 mandate for usage in all new bedroom circuits of new homes that become effective on January 1, 2008. However, concerns were voiced by some within the industry about the cost to implement such a requirement, including both the initial payout and the return on investment for the homebuilder and, by extension, the contractor.

National Electrical Manufacturers Association research in August 2007 of hardware stores and home centers found AFCIs priced from roughly $30 to $35, with standard circuit breakers priced between $2 and $4.1 Assuming the high-end price of $35, the cost differential between AFCIs and standard breakers is approximately $31 to $33, which means installing 12 AFCIs in an average home will increase the cost $372 to $396, or .20 percent of the national average home cost.2

That might seem expensive to some, especially considering a combination AFCI device is located behind the door of a load center. But the work of an AFCI as a proactive safety device shouldn’t be minimized—its ability to use advanced signal processing to detect a dangerous arc and open the affected circuit can prevent a fire from igniting in the first place. This differs from smoke alarms or even a sprinkler system, for example, which can be viewed as reactive devices because they detect a fire after it starts. Both smoke alarms and sprinklers are important safety systems and the lives and property they save are significant, but AFCIs could be considered a strong complement by mitigating an arc fault fast enough to result in a fire not starting in the first place.

According to NEMA, residential fires of an electrical origin are a major concern. In 2003, about 67,800 such fires occurred, resulting in $868 million in property losses, quoting data from the United States Fire Administration. What’s more, electrical fires are annually responsible for about 485 deaths and 2,300 injured people, not to mention the loss of a dwelling and sometimes everything in it, including pets and irreplaceable personal items.

Projecting combination AFCIs’ life- and property-saving potential is difficult; after all, very few near-misses are recorded or even known by homeowners. But statistics from the 1980s and early 1990s, following the adoption of the majority of GFCI requirements in the NEC, show that electrocution deaths significantly dropped. Of course, many factors played into that, but the statistics suggest GFCIs played a crucial role. A similar reduction scenario in home fires due to electrical incidents is projected following the combination AFCI expansion post-January 1, 2008.

Extensive support

The support and endorsement for AFCI is extensive. The electrical industry, including the Independent Electrical Contractors (IEC), National Electrical Contractors Association (NECA), International Brotherhood of Electrical Workers (IBEW), Underwriters Laboratories and the electrical inspection community have supported combination AFCI expansion to enhance electrical safety. The National Association of State Fire Marshals (NASFM) endorses installation of combination AFCI protection on all circuits in the home, not just those established by the 2008 NEC. The Consumer Product Safety Commission (CPSC) endorses the installation of combination AFCIs not only in new construction but also during the installation of new services in older homes.

AFCIs have come a long way in a short period of time. The contractor that understands AFCI technology and the implications of code requirements will be better prepared to adjust to the changes it will dictate on the job. Based on the industry embracing the expansion of combination AFCI protection in additional areas of the home as outlined in NEC-2008, electrical contractors, inspectors and homebuilders will be leading the way in not only electrical safety but overall home safety.

1 National Electrical Manufacturers Association whitepaper. "Upgrading the Home: Luxury vs. Safety.”

2 Ibid.

3 2008 NEC210.12(B)


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Uniformity in Disaster Recovery Inspections

Posted By Rich Dubiel, Tuesday, January 01, 2008
Updated: Friday, February 08, 2013

Most likely, by way of our television sets, we have all witnessed the unbelievable destruction and devastating consequences of one or another natural disaster. Certainly, hurricane Katrina and the December 26, 2004, Indian Ocean tsunami come to mind. For sure, many of you may also have been personally involved and will have a never-ending memory of the experience.

My personal experience with a natural disaster occurred when a hurricane-type storm struck the area where my family and I reside. We had no major damage, but we were without power for four days on that occasion. Inconvenient? Yes, but we considered ourselves blessed compared to others in the surrounding area who received considerably more damage, which required major renovations to their homes. Things got back to normal quickly, however. A few years back, relatives of ours were severely affected by the devastating winter ice storm that hit the upstate New York area, where in the winter the temperatures average a little above zero. Luckily, the storm caused no personal harm or any major destruction to their property. Still, they were without power in their home for weeks, and they had to deal with the effects of the power loss to their barn that housed over sixty head of milking livestock. For those of you not familiar with milking cattle, the cows had to be milked twice daily by hand, even though the milk could not be sold for process. This was a difficult time for them.

Photo 1. Katrina-damaged home in New Orleans

In the aftermath of hurricane Katrina, there was an awareness of how disaster procedures do not necessarily function as efficiently as intended. In fact, the Federal Emergency Management Protection Agency (FEMA) and the state and local emergency agencies received much criticism of their handling and lack of overall preparedness. One could argue that the criticism was justified. FEMA has acknowledged that there is cause for improvement. However, the most comprehensive emergency procedures will not be completely adequate for every catastrophe; this is because no disaster is scripted. I think everyone will agree that even a disaster plan that proved to have subsequent flaws was better than having no planned procedures at all. Nonetheless, many lessons have been learned from hurricane Katrina that will effect many changes until another unfortunate disaster teaches us additional lessons.


Photo 2. Street flooding is common across the country

While disaster plans must primarily address preventing loss of lives during the initial phase of the disaster, they must also address the post-initial phase (disaster recovery). This phase is when the electrical inspection process and electrical inspectors play a vital role. Recently, in a nearby area, I had the unfortunate experience of participating in the electrical inspection process in the aftermath of a devastating flood, which was not even close to anything I had personally witnessed before. It is hard to imagine the destruction, chaos, and personal suffering involved until you have personally witnessed such a situation. Even then, no one can completely comprehend what those who have been personally affected feel. During the initial stage of the flood, emergency evacuation procedures must have worked as planned because there was not one loss of life. During the days after the floodwaters had subsided (disaster recovery phase), I gradually came to realize that we did not learn as much as we could have from Katrina, at least not in my area or state.

As one of the electrical inspection agencies authorized to inspect the floodwater-damaged residential and commercial buildings, we had a plan to get inspectors into the area quickly if needed. By memo, I immediately reiterated our inspection policy and procedures with regard to floodwater-damaged equipment to both the inspectors in the area and to those who might be sent there. I initiated open dialog with top management so they could provide immediate assistance of any kind, if needed. So, while we had an organized plan that mobilized and prepared the inspectors to be confident in the mechanics of the type of electrical inspections facing them, we were not fully prepared for the emotional aspects (anxiety, frustration, shock, anger, and so forth) in dealing with all those affected. Certainly, the emotions of all the people affected by such a disaster will understandably run high; however, in my opinion, we could do better at keeping them to a minimum in the future.

As might be expected, from the start the inspectors and I were dealing with overworked and stressed-out contractors, codes officials, power company people, and home and business owners. These people had many questions, were confused and, in many cases, irate. Many were in actual shock because of the effects the disaster had on their lives. Of course, this situation has the potential to affect the inspectors in the same way.


Photo 3. Another damaged building in New Orleans

Because there were different municipalities’ code departments involved and different inspection agencies, there were often different criteria used to determine, in particular, when power should be, or could be, reestablished to a home or other structure. Initially, in one municipality after the flood waters receded, a group of inspectors went from house to house checking services that were under water and approving temporary power services. The power company then followed and reconnected the services with the stipulation that they had to be re-inspected within a given time period or again turned off. For obvious safety reasons, this practice was not done for long.

Our inspectors followed the recommended procedure in the National Electrical Manufacturers Association document, "Evaluating Water-Damaged Electrical Equipment,” and other procedures recommended by electrical wire manufacturers. Other inspection agencies either did not follow the document or interpreted it differently. For example, while we required all NM cable that was underwater for any time to be replaced, this was not necessarily always a requirement by other inspectors. Where there was some doubt as to when underground conductors needed replacement, particularly in dealing with the larger commercial service conductors, we required a recommendation by the wire manufacturer’s representative. In some instances, after testing and some remedial procedures, it was discovered the conductors did not require replacement. We followed the same procedures with regard to many motors and other types of equipment that received water damage. When an inspector had situations that were not clearly covered by any procedures or manufacturers’ documents, and there always are some, we would go with the conservative approach. Even though there may have been a strong possibility that just drying out a piece of equipment or cable would be acceptable, experience tells us that even strong possibilities should not be relied on when dealing with safety.

I began to receive what seemed to be a never-ending number of calls from agitated, confused and sometimes irate people. Interestingly, regardless of the level of agitation or initial anger expressed by the callers, and regardless of their not necessarily hearing what they wanted to hear, almost without exception, every caller either thanked me for taking their call or ended the call noticeably relieved. I believe this was because, as many said, they were finally able to talk to someone and get some of their questions answered. One caller said, "I want you to cancel the inspection I have scheduled with your agency immediately. I hear that another agency does not have all the requirements that your agency does.” After some discussion and at the end of the call he did not change his mind, but said, "Anyway, thank you for taking my call.” This was typical of the calls received, which certainly encouraged me to take or return every call that came in. Incidentally, this person called back a couple of times and finally decided to renew his application.

Many of the callers wondered why a neighbor’s house across the street had power turned on while our inspector required the service panel and, in some cases, service-entrance conductors to be replaced before allowing the same for their home. Some questioned why we required all NM cable that had been under water to be replaced, when other inspectors or contractors were telling them the cable needed only to be dried thoroughly. I also had calls from homeowners wondering why their insurance company would not pay for new NM cable, regardless of whether it was underwater or not. Many similar calls came in with people wondering why some were required to change this or that, while others were not. As could be expected, I had inspectors calling to ask if there was a way they could have something in hand to help explain our inspection requirements. One inspector suggested I allow him to hand out the private memo I had sent to all inspectors who would be working in the disaster area.

It was at this point, after getting management approval, that I allowed the inspectors to hand out the memo I had sent to them. As it turned out, this memo was circulated throughout the area and seemed to answer many questions and to ease some irritations from many affected by the disaster. The memo went something like the following:

"Inspectors: This is to reaffirm the inspection policies/procedures for floodwater affected electrical equipment. Basically, any electrical equipment that has been submerged for any length of time under floodwaters (service panels, meter channels, receptacles, GFCI receptacles, metal boxes, NM cable, MC cable, etc.) needs to be replaced. Thoroughly drying out and cleaning the equipment is not always sufficient no matter how extensive the process may be. Remember, floodwaters almost always deposit large amounts of contaminate that, even though invisible, will damage the equipment and create unsafe conditions in the near future. This is a proven fact gained from experiences in other flooding areas.

"You all have at your disposal guidelines for handling water-damaged electrical equipment.

"All equipment manufacturers recommend that such equipment be changed completely or that an opinion by a manufacturer’s representative be used where there is justifiable doubt.

"We must realize that this is a very trying time for any one affected by this flood, but it is our job and duty, difficult as it may be, to make sure every one of their structures is as safe as it can possibly be for the families and others that re-enter it. Remember it is better to face someone’s anger now than to be forever devastated by the fact that someone was injured or killed because we let down our guard.

"Also, prior to a structure being reenergized, confirmation from the AHJ must be received that the structure is sound and that the gas/fuel, if applicable, has been cleared. We don’t want to create another potential catastrophe.

"The people affected by this disaster need our help. This is what the New York Board of Fire Underwriters is all about.

"Should anyone have any questions or concerns, please contact your chief inspector as soon as possible. Every flood effect location you visit must have an application on file. Please direct people in need of filing to the Syracuse office, and their applications will be prioritized.”

I have lost count of the number of requests I have had from other inspectors, codes people, contractors, and so forth, for a clear copy of the above letter for duplication.

As mentioned briefly, I think we will all agree that we can do better in our disaster recovery efforts (certainly in my area). I am sure those personally affected will agree. I am referring only to disaster recovery as it pertains to electrical power recovery, although I would suspect that other areas of recovery could be improved on also. If nothing else, we need to have all inspectors, power providers, municipal codes enforcement people, FEMA representatives and home and property owners to be on the same page. That is, we need to have more uniform requirements and/or policies with regard to power reinstallation and interior wiring requirements post disaster.

While I do not pretend to have all the answers, my experience has left me with some thoughts and possible suggestions. First, we must set at least basic requirements that all inspectors would need to follow with regard to some specific disaster recovery situations (i.e., flooding, ice storm, and so forth). These requirements could certainly be derived from the excellent documents already existing and published by the most knowledgeable in their respective areas (i.e., National Electric Manufacturers Association, the various power providers, local and state codes agencies, wire manufacturers, FEMA, UL, IAEI, NFPA, and others). I see the possibility for one document, or set of documents, covering electrical disaster recovery requirements. Maybe a whole NEC code section is needed or perhaps a separate National Fire Protection document. Why not? We already have similar sections and documents published by many of these agencies. Of course, there will never be a document or set of rules that covers every situation; but, as mentioned, we certainly would be better with a more specific plan than with nothing at all.

In the aftermath of Katrina and subsequent disaster recovery initiatives, electrical inspections in New Orleans were suspended. Now an exhaustive investigation by Electrical Contractor magazine’s Jeff Griffin has shown that the suspensions have resulted in some rather unsafe conditions. Many buildings had power restored where water-exposed equipment had not been replaced. Apparently, what we are seeing now is that the emergency ordinance waiving electrical inspections put in place in New Orleans has potentially set the stage for another disaster.

Electrical Contractor magazine editor Andrea Klee, in a preface to Jeff Griffin’s investigation article wrote, "Present and future owners may be faced with shoddy work done, with liability on their own shoulders, and with no measures to have had proper inspections done. Of course, there’s pressure to get everyone home as quickly as possible, but is it right to cut corners and waive electrical inspection procedures that have been in place for decades? Pushing aside the protocol could further harm those who have already been through so much.” Who can argue with that?

In the final analysis, it is clear that we must do better to make disaster recovery initiatives for affected people not only safe, but also uniform for all. The stress these people face initially is terrible enough. Let us, who know what the consequences could be, not abandon our responsibility. We need to join our voices for change. To not do so, allows the possibly for more anxiety and even sorrow somewhere down the road.


Read more by Rich Dubiel

Tags:  Featured  January-February 2008 

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Using Electric LEDs in Electric Signs and Letters

Posted By Randy Wright, Tuesday, January 01, 2008
Updated: Friday, February 08, 2013

The sign industry is currently using LED light sources for many applications. LEDS were first introduced to the sign industry, I believe, on power source equipment as indicators for conditions and problems. As the LEDS came to be used in different applications such as taillights for vehicles, traffic control, warning lights and indicator lights, their applications expanded. Since this article applies to their application, we shall not explain the engineering or chemistry of the LED, nor will we explain how it makes light. This information is available in other articles and from the manufacturers.


Figure 1. Typical Installation Instructions

Applications in the sign industry increased as the lumens increased, originally by driving more energy into the LED, and currently by different designs. As the power is increased, however, there is a sacrifice of some energy saving, longevity of the product and an increase in the required maintenance of the light source. As the original red color could be pumped up enough to be used either exposed or placed behind plastic for channel letters, it became a competitor to the neon tube. The light source is low-voltage and perceived safe from arcing and fire. The installation procedure is perceived to be simple compared to the complex installation of the high-voltage requirements of neon installations. Now since the natural color of LEDS is at 1 watt and soon will be higher, different considerations will be needed because of the increased heat levels.

Since LEDS provide only directional light, the applications become more difficult because you do not have the same benefit of light bounce that neon and fluorescent have to offer. Your LED partner should be able to guide you in the correct installation and configuration procedures to provide the best lumen output to match the application. Since we deal only with listed electric signs, we must remember we can only use listed and recognized components to build our electric signs and channel letters. The components are controlled in UL 879, currently Section 4.18 Class 2 LED Components, which has 14 different sections with requirements. Please review all the sections before you start your manufacturing. These sections relate to the conditions of acceptability.

Figure 2. Typical Installation Instructions

Now where have we heard that before?

The conditions of acceptability for a component are every bit as important as bonding and grounding. The parts used in assembling or manufacturing listed electric signs have conditions of acceptability that need to be met when used in different applications. This is the way the part can be used based on its intended application. Some of the important items relate only to being allowed to be connected to Class 2 power supplies (30 volts or less), special requirements for wet locations, and connection in accordance with the National Electric Code, NFPA 70.

Secondary wiring is also a point of confusion. When wiring is run exposed, it must be a suitable power-limited tray (PLTC) cable or enclosed. The wire is furnished as required with the power supply and should have a means for connection supplied.

For permanently connected signs, the power supply is required to be enclosed.

Below are the installation instructions for these components; these are reprinted with permission from Underwriter Laboratories, Inc.

"4.18.4 Installation Instructions
"4.18.4.1 LED units shall be provided with installation instructions that include the following:
a) A location designation indicating the environmental condition for which the product has been evaluated (e.g., wet, damp, or dry location);
b) These products are only suitable for connection to a circuit from a Class 2 power source;
c) These products have not been evaluated for use when connected to a power source that does not comply with Class 2 voltage and energy limited supplies; and
d) For wet location products, "These products are not required to be enclosed or protected from weather.” 1


Figure 3. Typical Installation Instructions

The importance of these instructions is to insure you use the components with the correct conditions of acceptability in your listed electric sign. Each component manufacturer should have mounting, electrical, heat sink, and directional information printed either in the shipping containers or on their web site for your use.

Field installation

The next major issue is the field installation of electric signs, channel letters, and bonding and grounding connections in accordance with the National Electric Code, NFPA 70.

Chapter 6 Special Equipment

ARTICLE 600
Electric Signs and Outline Lighting

600.3 Listing. Electric signs, section signs, and outline lighting — fixed, mobile, or portable — shall be listed and installed in conformance with that listing, unless otherwise approved by special permission.

600.7 Grounding.Signs and metal equipment of outline lighting systems shall be grounded.2

These two sections are quite clear that electric signs and section signs (channel letters) are required to be listed. In addition, signs and metal equipment (channel letters) are to be bonded together and connected to the equipment grounding conductor. Without exception—and no exception is provided in Article 725—they all need to be grounded, low voltage included.

I have also included three pages from Neon Lighting, A Professional Advantage, with permission from the International Association of Electrical Inspectors, which shows typical installation instructions required to go with the LED signs and channel letters for their installation and final inspection.

In closing, there still seems to be some confusion concerning the use of different light sources. I have fielded calls from installers, manufacturers, inspectors, and some non-listed companies trying to build, install, or inspect electric signs and channel letters with LEDS. The most common question is, Must I bond and ground LED signs and letters? The standard answer is, YES. Dead metal in all electric signs and channel letters must be grounded.

Questions and commentsrandy@rkw-consulting.org

1 Reprinted from UL 879-8 June 6, 2005- revised May 24, 2006

2 Reprinted from the 2005 NEC


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