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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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IAEI West Virginia: Getting Back to the Grass Roots of Safety

Posted By Thomas A. Domitrovich, Friday, December 21, 2012
New electrical contractors enter our markets every year; these individuals perform work that electrical inspectors ultimately review. Involvement in activities in which these individuals participate, using the opportunities to educate, is getting to the grassroots of electrical safety. The IAEI West Virginia recognized an opportunity to be a leader in safety through involvement with the Skills-USA program in their state. Jack Jamison and a host of other key individuals worked hard to create a program that would challenge and educate the best of the best in West Virginia. Jack and his supporters successfully set the bar for the quality of electrical contractor that our markets demand. This team was working directly with students and their educators and helped to shape the mindset of the type of entry level contractor our industries need. This was an opportunity to drive the importance of workmanship and code-compliance that these individuals will take with them into the field.


Figure 1. Volunteers who served as judges

Figure 1. Volunteers who served as judges

SkillsUSA Overview

Photo 1. Students Take Written Exam. Each student was required to take a written exam before demonstrating their hands-on skills.

Photo 1. Students Take Written Exam. Each student was required to take a written exam before demonstrating their hands-on skills.

SkillsUSA is a national organization for students in trade, industrial, technical and health occupations education (www.SKillsUSA.org). This organization sponsors a SkillsUSA Championship annual event that recognizes achievements of career and technical education students. The program is commendable in that it encourages students to strive for excellence and take pride in their chosen occupations. In addition, it engages the educators of our future trade professionals to help them tweak their programs to better prepare their students for employment. Each technical school in West Virginia had an opportunity to participate. Those that participated sent their best student for the categories in which they have interest. West Virginia sent 21 students for the Residential Wiring challenge and 9 students for the Industrial Motor Controls competition. These events occur all over the United States.

The contests for the students are designed to test the skills needed for a successful entry-level individual in their occupational field. They are created and planned by technical committees made up of representatives of labor and management. Safety practices and procedures represent a portion of the contestant’s score that judges give to each student for both a written exam and practical hands on installation skills.

SkillsUSA touches on a wide array of occupations. IAEI West Virginia sponsored the residential wiring and industrial motor controls portions of this event. The purpose of the industrial motor controls program is to evaluate each contestant’s preparation for employment and to recognize outstanding students for excellence and professionalism in the field of industrial motor controls. The SkillsUSA industrial motor controls contest is defined by manufacturer and customer specifications, industry practice, federal regulations and industry standards such as theNational Electrical Code(NEC). The contest is divided into three parts: written, oral interview, and a series of testing stations. The program is designed to demonstrate knowledge of manufacturer and consumer specifications, industry practices, federal regulations and industry standards as well as the ability to apply this knowledge and manual proficiency in applying and installing electrical wiring methods and equipment.

Photo 2. Students Arrive Prepared. Each student that participated in the Residential Wiring or Motor Control portions of the program had a cubicle with a desk where they arranged their tools. Safety was a key aspect and each student was reviewed for clothing which included eye protection, hard hats and proper clothing.

Photo 2. Students Arrive Prepared. Each student that participated in the Residential Wiring or Motor Control portions of the program had a cubicle with a desk where they arranged their tools. Safety was a key aspect and each student was reviewed for clothing which included eye protection, hard hats and proper clothing.

The purpose of the residential wiring section is to evaluate each contestant’s preparation for employment and to recognize outstanding students for excellence and professionalism in the field of residential wiring. The contest assesses the ability of the student to perform jobs or skills selected from a list of competencies as determined by the SkillsUSA Championship technical committee. There is a written knowledge exam and a skills performance contest. The skills portion of the contest includes a series of workstations that have information and instruction sheets for wiring a residence or completing a light commercial installation. West Virginia focused on a residential installation.

The winners of this year’s program will represent West Virginia at the national competition in Kansas City, Missouri.

IAEI West Virginia Involvement

Jack Jamison, secretary for IAEI West Virginia, Jim Williams and Paul Linger teamed up to spearhead this event. These individuals had a long row to hoe, so to speak, in pulling together the resources to make this event happen. Their first order of business was to get the volunteers needed. Together, with the help of these other key individuals, they made this program quite a success. Volunteers received the support of their organizations to support this event (see figure 1).

Photo 3. Judges. After the students completed the practical installation portion of testing, volunteer judges reviewed and scored each student’s work. Scott Jolliff reviews the Gold Medalist’s work.

Photo 3. Judges. After the students completed the practical installation portion of testing, volunteer judges reviewed and scored each student’s work. Scott Jolliff reviews the Gold Medalist’s work.

The electrical program was started from scratch for the state of West Virginia. Jack and his team were faced with organizing volunteers to judge, managing logistical activities as well as creating the entire electrical program for both residential and motor controls. Efforts included development of exam materials, both written and practical installation plans, not to mention the product and equipment that was needed to implement the hands-on portion of the program. This team flexed their resources to assemble the product and resources needed to make this event happen. Local distributors, contractors and manufacturers played key roles in ensuring that the equipment they needed was delivered and in place. Key contributors for the event included:

  • Eaton Corporation
  • Legrand Pass & Seymour
  • Allen-Bradley
  • Hubbell
  • Leviton
  • Miller Engineering
  • Lowe’s
  • State Electric Supply company
  • West Virginia Electric Supply Company
  • The Hite Company
  • CED Mosebach Electric Supply Company

 

The Program

Photo 4. Learning Opportunity. Jack Jamison and other volunteers ensured this was more than a contest — it was a learning opportunity. Students would suffer the loss of points but in the end it is all about learning.

Photo 4. Learning Opportunity. Jack Jamison and other volunteers ensured this was more than a contest — it was a learning opportunity. Students would suffer the loss of points but in the end it is all about learning.

On March 26that 8:00 a.m., twenty-one residential wiring students secondary and post secondary and nine industrial motor control students sat at their desks to take a written exam (see photo 1). They had one hour to complete the written portion of the exam and then six hours to work on their practical installation skills through hands-on installation (see photo 2).

For the written exam portion of the challenge, the students sat at a desk to read and answer 34 multiple choice questions. Questions 1 through 30 directly pertained to theNational Electrical Code(NEC). Students were presented with problems that required them to reference theNECfor articles and sections to help choose the answer that best answered the question. For the Residential Wiring participants, everything from the 6-foot rule to box-fill calculations was covered. The last four questions focused directly on the hands-on portion of the challenge — the students had to draw the diagram that they would soon be building in their lab area.

Photo 5. Residential Gold Medal. Jack Jamison proudly shakes the hand of the Gold Medalist for the residential wiring section of SkillsUSA WV.

Photo 5. Residential Gold Medal. Jack Jamison proudly shakes the hand of the Gold Medalist for the residential wiring section of SkillsUSA WV.

Jack Jamison and his team of industry professionals made sure that the participating students were challenged but most importantly learned something (see photo 3). It was quite clear, once the hands-on portion of the program began, who was prepared and who was not for this competition. Because of the competitive environment, Jack and his team had no knowledge of who the students were, what their names were, or what schools they represented. In addition, helping students who stumbled during their tasks had to be compensated for through point deductions. When a student did ask for help, the advice and education they received were well worth the point penalties — the room was packed with industry experience. Passing on knowledge to those who will be entering into our markets, wiring our homes and/or commercial and industrial facilities, does a lot for safety.

The Challenge to Other Chapters

Getting involved with events like this and our newest electrical contractors just may open your eyes to how important it is that we as an industry get even more involved with students of electricity. IAEI and other trade organizations such as the International Brotherhood of Electrical Workers (IBEW) and the Independent Electrical Contractors Association (IEC) and others have great programs to cultivate and grow the knowledge of new and seasoned professionals in our markets. The involvement of these young individuals is a must. West Virginia IAEI demonstrated how this organization can get involved and has plotted a course for the future through this past program. Raising the awareness of IAEI educational programs to these individuals just entering our markets is a good opportunity to educate on safety and to grow membership.

Photo 6. Motor Control Gold Medal. Paul Linger and Jim Williams proudly present the Gold Medalist for the motor control section of SkillsUSA WV.

Photo 6. Motor Control Gold Medal. Paul Linger and Jim Williams proudly present the Gold Medalist for the motor control section of SkillsUSA WV.

It takes leadership to rally the troops, set the direction, and impact a life or possibly more by getting involved with the future of our industry. This involvement and leadership builds the brand of both organization and the individual — it helps to drive membership of the right demographics. Involvement of the young budding professional entering the market is what most nonprofit organizations lack. This is key membership that drives the future of the organization. These students appreciate the types of opportunities presented by the SkillsUSA program — it gives them an opportunity to demonstrate their abilities and to build their resumes as they enter the job market. These students could be our future electrical inspectors, future chapter presidents, treasurers and secretaries who will make our chapters function and thrive. I am proud to be a IAEI West Virginia member and was even more so during this event. These types of events occur in many chapters and more than likely never get mention or recognition. Those chapters should be commended for their efforts and others should be encouraged to get yet more involved. Together we can make a difference.

As always, keep safety at the top of your list and ensure you and those around you live to see another day. If you have any tips or ideas you would like to share, please feel free to send them to me at thomasadomitrovich@eaton.com. I look forward to your input to these articles and guidance for future articles.


Read more by Thomas A. Domitrovich

Tags:  July-August 2011  Safety in Our States 

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Risk comes from not knowing what you’re doing

Posted By Kathryn Ingley, Friday, July 01, 2011
Updated: Friday, December 21, 2012

So says Warren Buffett, one of the world’s most successful investors. His biography underlines this belief by telling how, since age 11, he has studied investing, fervently. He "looks at stocks as business, uses the market’s fluctuations to advantage, and seeks a margin of safety.”

Know what you’re doing — not a bad lesson for us. At least I’ve found that continually adding to my knowledge keeps me alert and helps me to avoid errors better. That same concept underlies IAEI’s focus on CEU training and the huge emphasis placed on the Certified Electrical Inspector programs in the United States and Canada.

Most writers in this issue focus on increasing our knowledge and applying it to installations and inspections and to examining current codes and making proposals for revisions or additions. Others apply the concept to investment, family safety, and training our successors.

Installations and Inspections

Christel Hunter reminds us that in electrical work "every connection is critical, because every connection has the potential to fail and create an outage or start a fire.” Then she shares how one can use best practices to avoid poor connections.

Steve Vidal examines the core transformer principles. "In astep-uptransformer, the voltage and impedance from primary to secondary are stepped up, while the current is stepped down. In astep-downtransformer, the voltage and impedance from primary to secondary are stepped down, while the current is stepped up.” Then he shows us the math, with easy-to-follow formulas and examples.

Steve Foran says that "safety leaders know that they must always be diligent and never take for granted the good fortunate of their safety performance. Simple question: What do you get when someone takes for granted a safety system, whether that is an inspection, a mechanical interlock, a design standard or an operating procedure? Answer: You have an accident waiting to happen.”

Jonathan Cadd, ever intrigued by history, walks us through the alternating vs. direct current chronicles. He emphasizes that the symbiotic relationship between AC and DC undergirds current technology and on-site generation methods. Those of us who may not know much about DC can depend on Jonathan to fill in the gaps.

Randy Hunter urges that equipment grounding conductors be thoroughly inspected and completely made up on the rough inspection. Then he explains the marking of grounded conductors.

Current Code and Proposals

IAEI Northern New Jersey and IEEE member, Thomas Rorro considers "the requirements for bonding in 2011National Electrical Code(NEC) 250.104, Bonding of Piping Systems and Exposed Structural Steel.” After he presents a complete analysis and evidence, he suggests a code change proposal.

John Wiles writes that "NEC690.64(B)(2)/705.12(D)(2) are written as an unrestricted requirement for sizing conductors and busbars fed from multiple sources. The conductor or busbar is protected for any combination of loads and/or multiple sources and locations of loads or sources connected to the busbar or conductor. It would appear that the existingCodemight be overly restrictive.”

Les Stoch reasons that "Rule 14-100 has requirements for reducing wire sizes connected to splitters, junction boxes and for control circuits such as pushbutton stations. The rule prescribes the minimum construction requirements for mechanical protection and maximum unprotected lengths of conductors so as to produce a safe installation. The rule is consistent in its overall requirements except for Sub-rule 100(d), which appears to be totally at odds with the remainder of the rule.”

"Any electrical design and installation is based on a number of conditions. Traditionally, such conditions include reliability, performance and economics,” explains Ark. Tsisserev. "Usually these conditions are dictated by the clients, who want such installations to function in a dependable manner and to be economically feasible. But regardless of the client’s criteria, one condition that must be consistently met by the design and installation issafety.This, latter condition is mandated by the appropriate codes and standards adopted for regulatory purpose in each jurisdiction where installation takes place.”

Investments, Family Safety and Successors

Jesse Abercrombie explores three common investment risks and shows us how by understanding them we can act responsibly and reduce their impact.

After reporting the sobering 2009 statistics of deaths, injuries and property damage resulting from fires, Allen Wright points out that the difference between death and survival in a fire is knowing what to do, preparing for disaster and practice. He offers 10 ways to protect your family from fires.

Thomas Domitrovich reports that "West Virginia IAEI recognized an opportunity to be a leader in safety through involvement with the SkillsUSA program in their state . . . to create a program that would challenge and educate the best of the best in West Virginia. . . . This was an opportunity to drive the importance of workmanship and code-compliance that these individuals will take with them into the field.”

Notknowing, then, increases risk — whether in games of chance, adventure sports, investments or ensuring electrical safety. So let’s learn together at IAEI seminars, whether in the classroom or online, at IAEI meetings, and in the Certified Electrical Inspector programs in the United States and Canada.Together, we really can make a difference!


Read more by Kathryn Ingley

Tags:  Editorial  July-August 2011 

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When is the 2011 UL White Book available, and what is new for 2011?

Posted By Underwriters Laboratories, Friday, July 01, 2011
Updated: Friday, December 21, 2012

Question

When is the 2011 UL White Book available, and what is new for 2011?

Answer

The 2011 UL White Book started distribution April 1, 2011. The UL White Book is considered by many as "Part 2 of the Code.” That is because without the White Book, it is difficult to determine compliance with the National Electrical Code (NEC). New to the 2011 White Book is the Index of Product Categories Correlated to the 2011 NEC, just pick your 2011 NEC section and find the applicable Listed product category Guide Information to comply with the Code section. In addition to the 2011 Index, there is also the Index of Product Categories Correlated to the 2008 NEC. Also new to the White Book is the Lightning Protection Application Guide, which is one of nine electrical marking and application guides in Appendix A of the White Book. In 2010, UL added the Alternative Energy Equipment and Systems Application Guide, which includes important application information on photovoltaic (PV) systems, wind turbines, generators, fuel cells, etc. So pick up a 2011 UL White Book or White Book CD at your local IAEI chapter meeting or at the annual IAEI Section Meetings this fall. You can also access a PDF version of the White Book online at www.ul.com/whitebook.


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Tags:  July-August 2011  UL Question Corner 

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Has UL investigated the effects of spray-on foam insulation on Type NM cable jackets or individual conductor insulation?

Posted By Underwriters Laboratories, Friday, July 01, 2011
Updated: Friday, December 21, 2012

Question

Has UL investigated the effects of spray-on foam insulation on Type NM cable jackets or individual conductor insulation?

Answer

UL has not specifically investigated the effects of spray-on foam building insulation on the jacket or insulation materials of NM cable. UL Lists NM cable under the product category Nonmetallic Sheathed Cable (PWVX), located on page 293 in the 2011 UL White Book and online at www.ul.com/database and enter PWVX at the category code search field. Type NM cable is evaluated for compliance with theStandard for Safety for Nonmetallic-Sheathed CableANSI/UL 719 for installation in accordance with Article 334 in theNEC. UL 719 does not address testing Type NM cable for spray foam building insulation compatibility.

UL is not aware of evidence that would suggest chemical corrosion. Once cured, these spray-on foam materials are inert solids and are not expected to effect the PVC insulation or jacket. While the curing process varies with the type of spray-on foam, the curing process usually begins immediately after application, with the foam being fully cured in 1 to 12 hours. Since the majority of these products do not contain volatile organic compounds (VOCs) or formaldehyde, these foams, in the non-cured state, are currently considered compatible with the cable insulation and jacket.

There have been noted cases of conductor insulation/jacket damage in installations where spray-on foam was applied in direct contact with insulated cables. It is possible that the damage noted is from incorrect application of the spray-on foam insulation, applying more spray-on foam in a single pass than recommended. Not following the manufacturer’s recommendations by applying the spray-on insulation in too thick of a layer could result in higher curing temperatures that may damage building materials, including electrical cables. Damage that is a result of thermal heating due to the curing process is consistent with the type of damage reported.


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Tags:  July-August 2011  UL Question Corner 

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10 Ways to Protect Your Family from Fires

Posted By Allen Wright, Friday, July 01, 2011
Updated: Friday, December 21, 2012

According to the National Fire Protection Association (NFPA):

In 2009 there were 1,348,500 fires reported in the U.S., resulting in over 3,000 deaths, in 17,050 injuries and in property damage of $12.5 billion. One home fire was reported every 87 seconds. Households can expect to average a home fire every 15 years or five fires in an average lifetime.

Pretty sobering statistics, which suggest it’s just a question of time before the average household is faced with the task of dealing with fire. The good news is that fire deaths have slowly declined over the past decade, due in large part to greater fire prevention awareness. In case of fire, the difference between death and survival is often simple preparedness and practice.

Here are 10 ways to protect your family from fires:

Fire Prevention Equipment

  • Install smoke detectors on every floor, and place one outside each sleep area.
  • Check smoke detector batteries every 6 months, at the same time you’re re-setting your clocks for daylight savings.
  • Another option is hard-wired smoke detectors. The advantage of these is that you will hear the alarm throughout the house regardless of which individual unit detects smoke or fire.
  • Purchase several ABC-class fire extinguishers for various locations such as the kitchen, utility room, hallway, and garage.
  • Train each family member in their proper operation, and when to use them.
  • Residential fire sprinkler systems have become very affordable, and can enhance the market value of your home considerably. Check out some other advantages at FEMA.

Fire Escape Planning

  • Draw an escape plan for your home.
  • Discuss with each family member where the escape routes are.
  • Identify two exits for every room in your home.
  • Practice fire escapes, in daylight and at night, at least twice a year.
  • Establish a meeting place near the home for the family to gather after evacuating.
  • Have the phone numbers for emergency personnel and nearby contacts programmed into your home and cell phones. Make sure every family member knows who to call, and how to call them.

Home Heating Precautions

  • Have chimneys and wood stoves inspected and cleaned at least once a year.
  • Wood stoves should be installed near walls made of fire-resistant material.
  • Fireplaces equipped with glass doors should burn with doors open to avoid creosote buildup in chimney. Close doors when fire is out.
  • Stack firewood away from house.
  • Space heaters should be placed away from all objects, and have a tip-over shut-off switch.

Kitchen Safety

  • Never leave cooking unattended. This is the leading cause of fires in the kitchen.
  • Keep flammable items like oven mitts and potholders away from the stove top.
  • Avoid wearing clothing that can come into contact with cooking surfaces (long sleeves, loose-fitting clothes).
  • Never use metal objects or aluminum foil in microwave ovens.
  • If fire erupts in your microwave oven, unplug it and leave the door closed.

Stay Plugged-in (Electrical Issues)

  • Discard extension cords or electrical devices which have frayed or damaged wiring or plugs.
  • Install safety covers over electrical outlets in households with small children.
  • Never bypass or remove the grounding terminal on three-prong plugs.
  • Be aware of the maximum current rating for each circuit in your home; never exceed their limits.
  • Do not run electrical cords in traffic areas or under rugs.

Smoking Savvy

  • If you must smoke, take it outside.
  • Use ashtrays that are sturdy and deep-sided.
  • Consider switching to fire-safe cigarettes, which are made with paper that burns slower.
  • Try using ashtrays or buckets filled with sand to ensure those butts are extinguished, and
  • Make sure they are before emptying those trays.

Put Your Worries to Bed

  • Keep bedroom doors closed at night. In the event of fire, they offer protection and help limit the spread of fire.
  • Check that electric blanket for faulty wiring. Make sure it’s UL-approved.
  • Pre-2007 mattresses should be replaced with newer ones meeting the 2007 Federal Mattress Flammability Standard.

Candles in the Wind

  • Never leave burning candles unattended.
  • Candles shouldbe placed in sturdy, non-flammable holders and positioned where they won’t be easily knocked over.
  • Keep matches out of children’s reach.
  • Keep candles away from drapes, which can blow into the flame or knock the candle over.

Car Care

  • Check vehicles regularly for fluid leaks or faulty wiring.
  • Examine exhaust system for excessive smoke plumes or leaks.
  • Avoid smoking in vehicles.
  • Keep a fire extinguisher in each of your vehicles.

Stormy Weather

  • Unplug electrical appliances during a storm.
  • Turn off air-conditioners.
  • Stay off corded phones.
  • Ensure outdoor antennae, electrical lines are properly grounded.

As you can see, fire prevention is 90% common sense. Preparedness, the other 10%, is really nothing more than putting that common sense into practice. Knowing what causes fires, or even how to prevent them, is a good start; but the difference between knowing and putting that knowledge to work, could be the difference between surviving and becoming another statistic.


Read more by Allen Wright

Tags:  Featured  July-August 2011 

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Safety and performance of Codes

Posted By Ark Tsisserev, Friday, July 01, 2011
Updated: Friday, December 21, 2012

Any electrical design and installation is based on a number of conditions. Traditionally, such conditions include reliability, performance and economics. Usually these conditions are dictated by the clients, who want such installations to function in a dependable manner and to be economically feasible.

But regardless of the client’s criteria, one condition that must be consistently met by the design and installation issafety.

This, latter condition is mandated by the appropriate codes and standards adopted for regulatory purpose in each jurisdiction where installation takes place.

Design and installation of electrical equipmentmust meet safety requirements of the Canadian Electrical Code adopted for administrative use in a province, territory or municipality.

Although the CE Code establishes minimum requirements forelectrical safetyin installations, it also covers specificfire safety provisionsfor certain equipment.

For example, Rule 2-124 of the CE Code governs criteria for fire stopping in fire separations, and it references the National Building Code of Canada (NBCC) for necessary means — to comply with these fire stopping requirements.
Rule 2-126 of the CEC mandates flame spread requirements for electrical conductors depending on a type of building construction or on location of these conductors in a building.

This rule also references fire protectionprovisionsof the NBCC for applicable FT marking of combustible insulation or jackets of electrical conductors.

Another such example could be illustratedby the requirement of Rule 32-200 for protection of conductors supplying a fire pump against exposure to fire. Appendix B Note on this rule also explains fire protection provisions of the NBCCin this regard.

Rule 32-110, for instance, regulates installation of carbon monoxide alarms and smoke alarms in the dwelling units. This rule also provides important explanatory references to the NBCC provisions for installation of these electrically connected fire safety devices

Appendix G of the CEC provides a complete cross-reference to the NBCC in respect to fire protection provisions for installation of electrical equipment, and the Appendix Gserves as a useful tool to the electrical designers, installers and regulators.
However, there are some situations where electrical designers and installers could beconfused on the extent of fire safety requirements of the NBCC.As the result, impact on the electrical design and installations might be quite drastic.

Let’s explore a few particular situations.
One of such subjects for misconception is use of locking devices on access doors to a typical commercial tenant unit. If the locking of thedoor is intended to prevent egress froma building or a tenant space, then only the use of electromagnetic locks (that do not incorporate latches, pins or similar devices that might keep the door in the closed position) is permitted by the NBCC, provided that the electromagnetic lock will release upon activation of the building fire alarm system, upon loss of power, or upon actuation of a manually operated switch accessible to authorized personnel. And such egress door must be opened from the inside with not more than one releasing operation and without requiring keys or specialized knowledge — by applying a force of not more than 90 N to the door opening hardware, so this force will initiate an irreversible process that will release the electromagnetic locking device within 15 s. And this is not the only condition that is placed by Sentence 3.4.6.15.(4) of the NBCC in conjunction with a permitted use of the electromagnetic lock.
Therefore, an electrical designer and electrical installer must take into account a need for interlocks required by the NBCC and a need for the wiring methods to be consistent with provisions of the CEC for Class 1 circuits (as this is a life safety application).

Of course, a building permit would be required to be obtained before an application for the electrical permit is submitted. Lack of understanding of the fire safety requirements of the NBCC in design and installation of an electrically connected locking device might adversely impact on a fire safety by preventing expedient exiting from a building.

If, however, a designer is incorporating a locking device only as meansof access control to a tenant unit, then the NBCC fire safety provisions do not apply for such installation, no building permit would be required in conjunction with such electrical work, and wiring of such locking devices would have to simply meet provisions of Section 16 of the CE Code for a typical Class 2 circuit (i.e., for a typical security system installation). As it could be seen from this example, a difference in design and installation could be very tangible.

Let’s review another example:
use of a UPS.

Firstof all, we’d have to clearly understand the intent of such use. If typical UPS equipment is utilized as a backup power supply source for such loads as IT equipment, kitchen preparation equipment, sump pumps, etc., then the NBCC and the CEC do not restrict such use of a UPS. It could be installed in accordance with the applicable provisions of the CE Code. If, however, a designer intends to use a UPS as arequired source of the emergency power supply, such application could be problematic (despite the fact that a typical UPS could function as a dependable source of the emergency power). The problem withsuch use is that the NBCC (Articles 3.2.7.4. and 3.2.7.9.) and the CE Code (Rule 46-202) only allow use of batteries, generators or a combination of bothas the emergency powersupply source.

In fact, Article 700, Emergency Systems, and Article 701, Legally Required Standby Systems, of the NEC also permit use of batteries or generators as the source of the emergency power supply. No UPS is specifically recognized by each of the referenced codes for such purpose.Thus, if a designer utilizes a UPS unit as the emergency power supply source for life safety systems defined in Rule 46-002or for essential electrical systems described in Rule 24-302 of the CEC, and such use of a UPS is undertakeninstead of the required batteries or a generator, then this approach is a definite recipe for trouble, as this approach is inconsistent with the NBCC and the CEC, and the regulators would not accept it.

If, however, a UPS unit is used as a convenient means for a secondary backup to a battery or a generator, this approach does not conflict with the life and fire safety provisions of the NBCC and the CEC.

One more example related to the fire safety could be also appropriate in this discussion. If a designerdecides to use a generator as a backup power source forthe IT loads, and such generator is not required by the NBCC to be used as the emergency power source for life safety systems, then all loads connected to this generator could be supplied via a single transfer switch. If, however, the generator is used as the emergency power supply source for any component of life safety system defined in Rule 46-002 of the CE Code, then all life safety system loads must be supplied from the generator via a dedicated transfer switch [see Rule 46-108(5) and Figure 8 of the CEC].

Let’s switch gears, and review performance aspectsof a typical electrical system in respect to a selective coordination of the overcurrent devices installed in the system.

Does the CE Code mandate coordination of the overcurrent devices in an electrical system, and does such coordination represent a
safety issue from the Code perspective?

In general (except for a few specific instances shown below) the CE Code does not mandate selective coordination of the overcurrent devices, as such coordination deals with a performance of the system components but not with the safety of the system. Therefore, in order to ascertain the acceptable performance of an electrical system, the designers must take into the account a good engineering practice in providing a selective coordination of the overcurrent devices installed in various parts of the system. Otherwise, a single fault in a branch circuit might disconnect the entire system if the overcurrent devices in branch circuits are not coordinated with the overcurrent devices installed in distribution feeders or in the building service. If not sure how to resolve selective coordination issues, the designers should communicate these issues with the experts representing manufacturers of the overcurrent devices.

However, there are several places in the CE Code, where selectivecoordinationis specifically mandated by the Code requirements.

Rule 14-102(8), for example, permits use of upstream protective device settings to exceed the values mandated by Subrule (2) in ground fault schemes where it is necessary to obtain desired coordination between the overcurrent devices.

Appendix B Note on Rule 32-206 (which explains provisions for overcurrent protection in a fire pump circuit) clarifies that the overcurrent protection selected in the circuit breaker installed upstream of a fire pump controller should be coordinated with the overcurrent device inside the fire pump controller "in a such a manner that the upstream overcurrent device does not disconnect the circuit prior to the operation of the fire pump controller overcurrent device.” The reason for such reference in the Code is quite obvious — fire safety.

A similar fire safety provisionis the basis for coordination requirement of Rule 46-206(1) of the CEC— between the generator overcurrent protection device and overcurrent devices installed in feeders and branch circuits that supply life safety systems and other electrical equipment connected to the load side of the emergency generator.This rule mandates selective operation of the branch-circuit overcurrent devicewhen a fault occurs in that branch circuit. The designers should be aware that in a distribution arrangement where the main overcurrent device is rated, let’s say, at 1600 A and downstream overcurrent devices are rated at 400 A or 200 A, compliance with this coordination criteria would not create a problem. But if the main overcurrent device is set, let’s say at 400 A, and downstream feeder overcurrent devices are rated at 200 A or 100 A, then it would be quite difficult to accomplish the desired coordination, and the manufacturing experts should be consulted on the best approach in solving this issue.

And as usual, designers and installers should discuss all questionable aspects of relevant codes and standards with the applicable AHJs, so there are no unpleasant surprises when design or installation is completed, and the regulators are asked to accept this design or installation.


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Tags:  Canadian Perspective  July-August 2011 

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IAEI West Virginia: Getting Back to the Grass Roots of Safety

Posted By Thomas A. Domitrovich, Friday, July 01, 2011
Updated: Friday, December 21, 2012

New electrical contractors enter our markets every year; these individuals perform work that electrical inspectors ultimately review. Involvement in activities in which these individuals participate, using the opportunities to educate, is getting to the grassroots of electrical safety. The IAEI West Virginia recognized an opportunity to be a leader in safety through involvement with the Skills-USA program in their state. Jack Jamison and a host of other key individuals worked hard to create a program that would challenge and educate the best of the best in West Virginia. Jack and his supporters successfully set the bar for the quality of electrical contractor that our markets demand. This team was working directly with students and their educators and helped to shape the mindset of the type of entry level contractor our industries need. This was an opportunity to drive the importance of workmanship and code-compliance that these individuals will take with them into the field.


Figure 1. Volunteers who served as judges

SkillsUSA Overview

SkillsUSA is a national organization for students in trade, industrial, technical and health occupations education (www.SKillsUSA.org). This organization sponsors a SkillsUSA Championship annual event that recognizes achievements of career and technical education students. The program is commendable in that it encourages students to strive for excellence and take pride in their chosen occupations. In addition, it engages the educators of our future trade professionals to help them tweak their programs to better prepare their students for employment. Each technical school in West Virginia had an opportunity to participate. Those that participated sent their best student for the categories in which they have interest. West Virginia sent 21 students for the Residential Wiring challenge and 9 students for the Industrial Motor Controls competition. These events occur all over the United States.


Photo 1. Students Take Written Exam. Each student was required to take a written exam before demonstrating their hands-on skills.

The contests for the students are designed to test the skills needed for a successful entry-level individual in their occupational field. They are created and planned by technical committees made up of representatives of labor and management. Safety practices and procedures represent a portion of the contestant’s score that judges give to each student for both a written exam and practical hands on installation skills.

SkillsUSA touches on a wide array of occupations. IAEI West Virginia sponsored the residential wiring and industrial motor controls portions of this event. The purpose of the industrial motor controls program is to evaluate each contestant’s preparation for employment and to recognize outstanding students for excellence and professionalism in the field of industrial motor controls. The SkillsUSA industrial motor controls contest is defined by manufacturer and customer specifications, industry practice, federal regulations and industry standards such as the National Electrical Code (NEC). The contest is divided into three parts: written, oral interview, and a series of testing stations. The program is designed to demonstrate knowledge of manufacturer and consumer specifications, industry practices, federal regulations and industry standards as well as the ability to apply this knowledge and manual proficiency in applying and installing electrical wiring methods and equipment.


Photo 2. Students Arrive Prepared. Each student that participated in the Residential Wiring or Motor Control portions of the program had a cubicle with a desk where they arranged their tools. Safety was a key aspect and each student was reviewed for clothing which included eye protection, hard hats and proper clothing.

The purpose of the residential wiring section is to evaluate each contestant’s preparation for employment and to recognize outstanding students for excellence and professionalism in the field of residential wiring. The contest assesses the ability of the student to perform jobs or skills selected from a list of competencies as determined by the SkillsUSA Championship technical committee. There is a written knowledge exam and a skills performance contest. The skills portion of the contest includes a series of workstations that have information and instruction sheets for wiring a residence or completing a light commercial installation. West Virginia focused on a residential installation.The winners of this year’s program will represent West Virginia at the national competition in Kansas City, Missouri.

IAEI West Virginia Involvement

Jack Jamison, secretary for IAEI West Virginia, Jim Williams and Paul Linger teamed up to spearhead this event. These individuals had a long row to hoe, so to speak, in pulling together the resources to make this event happen. Their first order of business was to get the volunteers needed. Together, with the help of these other key individuals, they made this program quite a success. Volunteers received the support of their organizations to support this event (see figure 1).


Photo 3. Judges. After the students completed the practical installation portion of testing, volunteer judges reviewed and scored each student’s work. Scott Jolliff reviews the Gold Medalist’s work.

The electrical program was started from scratch for the state of West Virginia. Jack and his team were faced with organizing volunteers to judge, managing logistical activities as well as creating the entire electrical program for both residential and motor controls. Efforts included development of exam materials, both written and practical installation plans, not to mention the product and equipment that was needed to implement the hands-on portion of the program. This team flexed their resources to assemble the product and resources needed to make this event happen. Local distributors, contractors and manufacturers played key roles in ensuring that the equipment they needed was delivered and in place. Key contributors for the event included:Eaton Corporation

  • Legrand Pass & Seymour
  • Allen-Bradley
  • Hubbell
  • Leviton
  • Miller Engineering
  • Lowe’s
  • State Electric Supply company
  • West Virginia Electric Supply Company
  • The Hite Company
  • CED Mosebach Electric Supply Company

The Program

On March 26th at 8:00 a.m., twenty-one residential wiring students secondary and post secondary and nine industrial motor control students sat at their desks to take a written exam (see photo 1). They had one hour to complete the written portion of the exam and then six hours to work on their practical installation skills through hands-on installation (see photo 2).For the written exam portion of the challenge, the students sat at a desk to read and answer 34 multiple choice questions. Questions 1 through 30 directly pertained to the National Electrical Code (NEC). Students were presented with problems that required them to reference the NEC for articles and sections to help choose the answer that best answered the question. For the Residential Wiring participants, everything from the 6-foot rule to box-fill calculations was covered. The last four questions focused directly on the hands-on portion of the challenge — the students had to draw the diagram that they would soon be building in their lab area.


Photo 4. Learning Opportunity. Jack Jamison and other volunteers ensured this was more than a contest — it was a learning opportunity. Students would suffer the loss of points but in the end it is all about learning.


Photo 5. Residential Gold Medal. Jack Jamison proudly shakes the hand of the Gold Medalist for the residential wiring section of SkillsUSA WV.

Jack Jamison and his team of industry professionals made sure that the participating students were challenged but most importantly learned something (see photo 3). It was quite clear, once the hands-on portion of the program began, who was prepared and who was not for this competition. Because of the competitive environment, Jack and his team had no knowledge of who the students were, what their names were, or what schools they represented. In addition, helping students who stumbled during their tasks had to be compensated for through point deductions. When a student did ask for help, the advice and education they received were well worth the point penalties — the room was packed with industry experience. Passing on knowledge to those who will be entering into our markets, wiring our homes and/or commercial and industrial facilities, does a lot for safety.

The Challenge to Other Chapters

Getting involved with events like this and our newest electrical contractors just may open your eyes to how important it is that we as an industry get even more involved with students of electricity. IAEI and other trade organizations such as the International Brotherhood of Electrical Workers (IBEW) and the Independent Electrical Contractors Association (IEC) and others have great programs to cultivate and grow the knowledge of new and seasoned professionals in our markets. The involvement of these young individuals is a must. West Virginia IAEI demonstrated how this organization can get involved and has plotted a course for the future through this past program. Raising the awareness of IAEI educational programs to these individuals just entering our markets is a good opportunity to educate on safety and to grow membership.


Photo 6. Motor Control Gold Medal. Paul Linger and Jim Williams proudly present the Gold Medalist for the motor control section of SkillsUSA WV.

It takes leadership to rally the troops, set the direction, and impact a life or possibly more by getting involved with the future of our industry. This involvement and leadership builds the brand of both organization and the individual — it helps to drive membership of the right demographics. Involvement of the young budding professional entering the market is what most nonprofit organizations lack. This is key membership that drives the future of the organization. These students appreciate the types of opportunities presented by the SkillsUSA program — it gives them an opportunity to demonstrate their abilities and to build their resumes as they enter the job market. These students could be our future electrical inspectors, future chapter presidents, treasurers and secretaries who will make our chapters function and thrive. I am proud to be a IAEI West Virginia member and was even more so during this event. These types of events occur in many chapters and more than likely never get mention or recognition. Those chapters should be commended for their efforts and others should be encouraged to get yet more involved. Together we can make a difference.

As always, keep safety at the top of your list and ensure you and those around you live to see another day. If you have any tips or ideas you would like to share, please feel free to send them to me at thomasadomitrovich@eaton.com. I look forward to your input to these articles and guidance for future articles.


About Thomas A. Domitrovich: Thomas A. Domitrovich is a national application engineer with Eaton Corporation in Pittsburgh, Pennsylvania. He has nineteen years of experience as an electrical engineer and is a LEED accredited professional. Thomas is active in various trade organizations on various levels including the International Association of Electrical Inspectors (IAEI), Institute of Electrical and Electronic Engineers (IEEE), National Electrical Manufacturer’s Association (NEMA) and the National Fire Protection Association (NFPA). Thomas is involved with and chairs various committees for NEMA and IEEE and is an alternate member on NFPA 73. He is very active in the state-by-state adoption process of NFPA 70, working closely with review committees and other key organizations in this effort.

Tags:  July-August 2011  Safety in Our States 

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What’s Wrong with Rule 14-100?

Posted By Leslie Stoch, Friday, July 01, 2011
Updated: Friday, December 21, 2012

Rule 14-100 has requirements for reducing wire sizes connected to splitters, junction boxes and for control circuits such as pushbutton stations. The rule prescribes the minimum construction requirements for mechanical protection and maximum unprotected lengths of conductors so as to produce a safe installation. The rule is consistent in its overall requirements except for Sub-rule 100(d), which appears to be totally at odds with the remainder of the rule.

We see that Rule 14-100(d) specifies that conductors from the secondary side of a high voltage transformer (impedance up to 7.5%) may be installed without any limitation in length as long as:

  • they terminate in overcurrent protection,
  • the transformer has secondary protection, maximum 250% of FLA,
  • the transformer’s primary side is protected in accordance with Rule 26-252(1), (2) and (3); and
  • the wiring is protected against mechanical damage.

Let’s look at an example – installation of a 5000 kVA, 44 kV/600V transformer. The secondary full load amperes of this transformer will be approximately 5000 amperes. If the transformer’s secondary overcurrent protection does not exceed 250%, Table 50 permits overcurrent protection on the primary side up to 600% FLA for a circuit-breaker and 300% for fuses.

Let’s assume that the transformer has primary protection set to 600% as permitted by Table 50. This would allow up to 30,000 amperes secondary fault current (6 x 5000 amperes). Assume secondary protection set to 150% FLA at the load end of the secondary conductors would provide overload protection. Since overcurrent protection is located at the load end, 30,000 amperes short-circuit protection for the conductors will be provided by the transformer’s primary side protection. And you likely noticed that the maximum length of unprotected wiring is unspecified.

In comparison, let’s look at Rule 14-100(c) which permits conductor sizes to be reduced at splitters or junction boxes as long as:

  • the reduction in ampacity is to not less than 1/3 of the larger,
  • the conductors are protected from mechanical damage,
  • the conductors terminate in overcurrent protection no greater than the ampacities of the conductors; and
  • the of conductor length is no greater than 7.5 m.

An example might be a tap from a 600-volt, 600-ampere splitter. Here the conductor ampacity must not be reduced to less than 200 amperes and the length of unprotected wiring restricted to maximum 7.5 m. One must provide 200-ampere overcurrent protection.
Based on our two examples, we can summarize the differences between Rules 14-100 (d) and (c) as shown in table 1.


Table 1. Difference between Rules 14-100 (d) and (c)

No doubt you noticed that in neither example is there any overcurrent protection at the conductors’ point of supply. In our second example, the wiring length is restricted to 7.5 m. In the first example even though the conductors may experience much higher fault currents, there is no restriction in conductor length. What do you think?

As with previous articles, you should always consult with the electrical inspection authority for a more precise interpretation in each province or territory as applicable.


About Leslie Stoch: Leslie Stoch, P. Eng, is principal of L. Stoch & Associates, providing electrical engineering and ISO 9000 quality systems consulting. Prior to that, he spent over 20 years with Ontario Hydro as an electrical inspection manager and engineer. Les holds a B. S. in electrical engineering from Concordia University in Montreal.

Tags:  Canadian Code  July-August 2011 

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What’s Wrong with Rule 14-100?

Posted By Leslie Stoch, Friday, July 01, 2011
Updated: Friday, December 21, 2012

Rule 14-100 has requirements for reducing wire sizes connected to splitters, junction boxes and for control circuits such as pushbutton stations. The rule prescribes the minimum construction requirements for mechanical protection and maximum unprotected lengths of conductors so as to produce a safe installation. The rule is consistent in its overall requirements except for Sub-rule 100(d), which appears to be totally at odds with the remainder of the rule.

We see that Rule 14-100(d) specifies that conductors from the secondary side of a high voltage transformer (impedance up to 7.5%) may be installed without any limitation in length as long as:

  • they terminate in overcurrent protection,
  • the transformer has secondary protection, maximum 250% of FLA,
  • the transformer’s primary side is protected in accordance with Rule 26-252(1), (2) and (3); and
  • the wiring is protected against mechanical damage.

Let’s look at an example – installation of a 5000 kVA, 44 kV/600V transformer. The secondary full load amperes of this transformer will be approximately 5000 amperes. If the transformer’s secondary overcurrent protection does not exceed 250%, Table 50 permits overcurrent protection on the primary side up to 600% FLA for a circuit-breaker and 300% for fuses.

Let’s assume that the transformer has primary protection set to 600% as permitted by Table 50. This would allow up to 30,000 amperes secondary fault current (6 x 5000 amperes). Assume secondary protection set to 150% FLA at the load end of the secondary conductors would provide overload protection. Since overcurrent protection is located at the load end, 30,000 amperes short-circuit protection for the conductors will be provided by the transformer’s primary side protection. And you likely noticed that the maximum length of unprotected wiring is unspecified.

In comparison, let’s look at Rule 14-100(c) which permits conductor sizes to be reduced at splitters or junction boxes as long as:

  • the reduction in ampacity is to not less than 1/3 of the larger,
  • the conductors are protected from mechanical damage,
  • the conductors terminate in overcurrent protection no greater than the ampacities of the conductors; and
  • the of conductor length is no greater than 7.5 m.

An example might be a tap from a 600-volt, 600-ampere splitter. Here the conductor ampacity must not be reduced to less than 200 amperes and the length of unprotected wiring restricted to maximum 7.5 m. One must provide 200-ampere overcurrent protection.
Based on our two examples, we can summarize the differences between Rules 14-100 (d) and (c) as shown in table 1.


Table 1. Difference between Rules 14-100 (d) and (c)

No doubt you noticed that in neither example is there any overcurrent protection at the conductors’ point of supply. In our second example, the wiring length is restricted to 7.5 m. In the first example even though the conductors may experience much higher fault currents, there is no restriction in conductor length. What do you think?

As with previous articles, you should always consult with the electrical inspection authority for a more precise interpretation in each province or territory as applicable.


Read more by Leslie Stoch

Tags:  Canadian Code  July-August 2011 

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Are You the Weakest Link?

Posted By Christel Hunter, Friday, July 01, 2011
Updated: Friday, December 21, 2012

Good workmanship requires that the professional electrician make sure that equipment is suitable for the installation and used in ways that comply with applicable codes and job requirements. Since most electrical equipment must be physically connected by some form of conductor, those connections are critical to the long-term reliability and safety of the installed electrical system. Developing good connection techniques and understanding what makes a good connection are the hallmarks of a professional electrician.


Photo 1. Listing Mark

Every connection is critical, because every connection has the potential to fail and create an outage or start a fire. Connections are the most likely point of failure in an electrical system, but it may take years after the initial poor connection is made for the connection to fail. Rarely is the reason for failure attributed to the initial installation, even though it has been demonstrated repeatedly that improper torque will eventually lead to failure of an electrical connection.

If you look at the world of electrical equipment, you’ll find inspections and quality control at every step: the conductors, connectors and equipment are all inspected and listed by a third party, typically a nationally recognized listing agency. Electrical manufacturers also have internal quality control procedures to verify that the products and components meet the applicable standards and expectations.


Photo 2. Set-screw connections

Once the equipment gets onto the jobsite, the electrician verifies that he or she has the right components for the job. This includes appropriately sized equipment, compatible connectors and the right type of conductor. Electrical inspectors typically check to verify the equipment and installation meet theNational Electrical Code.

So where does this system break down?All along the line we have inspections, quality control, and more inspections. Unfortunately, one of the most critical parts of ensuring a safe and reliable electrical system is often given little thought and less attention: making connections. Particularly with mechanical set-screw connections, most electricians believe that as long as you have it pretty tight, the connection is good. Few electricians take the care to use a torque wrench or torque screwdriver and make sure that those connections are tightened to the manufacturer’s recommended torque values. Inspectors may check to make sure the connectors don’t easily slip out of the connector, but they can’t be there to watch every connection get tightened with a torque wrench or screwdriver.

TheNECgives clear instructions regarding electrical connections. In 110.14(A) Terminals, theCodestates, "Connection of conductors to terminal parts shall ensure a thoroughly good connection without damaging the conductors and shall be made by means of pressure connectors (including set-screw type), solder lugs, or splices to flexible leads.” So with set-screw type connectors, how can we ensure a "thoroughly good connection” and do it so that we avoid "damaging the conductors” in the process?


Photo 3. Scale on Torque Wrench

The only reliable way to make a good connectionwithout damaging the conductor in a typical set-screw type connector is to tighten the screw to the recommended torque value. The only way to accurately tighten the screw to the proper value is to use a torque instrument, either a torque wrench or a torque screwdriver, depending on the type of connector. A study1performed in 2009 showed that over half of set-screw connections made without a torque wrench were under-tightened to values less than 80%. Nearly one-third of connections were tightened to values less than 50% of the recommended torque. One-quarter were over-tightened to values higher than 120% of the recommended torque. What do all these numbers mean? They mean that if you do not use a torque tool to tighten set-screw connectors, you only have a 25% chance of getting within 20% of the recommended torque. On the other hand, if you use a torque tool, you can make every connection correctly every time, and thereby comply with the requirements of theNEC.

In the 2011NEC, there is a new Informative Annex I, "Recommended Tightening Torque Tables from UL Standard 486A-B.” UL Standard 486A-B is titled "Wire Connectors” and is used to list connectors for aluminum, copper and copper-clad aluminum conductors. There are two columns ("A” and "B”) in each of the tables in Annex I. When used for listing connectors, Column A values are used for current-cycling tests, and Column B values are used for all other tests. When used for field connections, the values in Column B are the appropriate torque values to use. Although manufacturers can and do specify differing torque values (with appropriate testing) for connections, the standard values in Column B are commonly used. These values correspond to those published by major connector manufacturers such as Burndy, ILSCO and others.


Photo 4. Torque Screwdriver

Annex I states that "In the absence of connector or equipment manufacturer’s recommended torque values, Table I.1, Table I.2, and Table I.3 may be used to correctly tighten screw-type connections for power and lighting circuits.*” The asterisk directs the reader to the statement "For proper termination of conductors, it is very important that field connections be properly tightened. In the absence of manufacturer’s instructions on the equipment, the torque values given in these tables are recommended. Because it is normal for some relaxation to occur in service, checking torque values sometime after installation is not a reliable means of determining the values of torque applied at installation.”


Photo 5. Torque Values on Equipment Label

These statements tell the user two important things.First, only use the Annex I, Column B values if specific torque values are unavailable for some reason (for example, older equipment with missing labels). Second, tightening connections to the recommended value in the field is critical for terminating conductors. Given the requirements in 110.14 and the information provided in Informative Annex I, there is no logical reason for an electrician not to use the proper tools and methods to terminate conductors.


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Tags:  Featured  July-August 2011 

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