Print Page   |   Contact Us   |   Sign In   |   Join
November-December 2009
Share |

September-October 2009 CoverSeptember-October 2009


Stories are available to subscribers or members only. Join now

[Stories marked with a * may be viewed by nonmembers.]







Separately Derived Systems

by Chuck Mello

The topic of grounding and bonding as it relates to the National Electrical Code (NEC) and proper installations still seems to be a mystery to many electricians, engineers and inspectors. Read more

Perspectives on PV

* Making the AC Utility Connection

by John Wiles

Connecting the utility-interactive inverter to the utility grid properly is critical to the safe, long-term, and reliable operation of the entire system. The ac output circuit requirements and the circuits that carry the inverter current in the premises wiring are somewhat complex. However, meetingCoderequirements can and should be accomplished to ensure a safe and durable system. Read more

Not Suitable for Medical Use — Electrical Safety Testing Under Attack

by Greg Smith

You’re on the operating table, the surgery is almost over. The procedure has gone well. The doctors and nurses are walking in liquid on the floor covered with antiseptic, your blood, and other fluids. As your doctor is making the final repairs, a nurse is at the computer typing in some data; then she turns to assist the doctor, steadying herself with one hand on the computer monitor. As she touches the doctor, the faulty PC sends its stray current through both of them and directly into your heart. They feel almost nothing, but you are especially vulnerable and in a few seconds, it’s too late, the damage has been done. Read more

Arc Mitigation – A Three-Step Approach

by Andrew Cochran

With any hazard there is a definable risk and a definable impact and it is no different for the arc-flash hazard. Quite often the impact in business interruption far outweighs the physical damage to equipment and industry statistics would suggest that the average physical equipment damage is around $50,000 and the business interruption cost around $85,000 per incident. Read more

The Peninsular Project

by Paul W. Abernathy

Requirements for the correct location and placement of a receptacle on a peninsular are found in Article 210, Part III. It is more specifically found in subsection 210.52(C)(3).Read more

Rooftop Wiring Methods and Temperature Correction

by Randy Hunter

Since at least 1940, the National Electrical Code has contained a requirement for ampacity correction of installations subject to high temperature conditions. In the 2005 NEC, a new fine print note was added to inform code users that if conductors in conduit were exposed to direct sunlight in close proximity to rooftops, they might experience an additional 30°C temperature rise above ambient (NEC-2005, 310.10 FPN 2). Read more

Analysis of Changes, NEC-2011 – Part II

by Keith Lofland

In the previous edition of the IAEI News, we took a look at some of the more significant changes that have been proposed for the upcoming NEC-2011 in Chapters 1–3. Let’s continue that process by taking a look at proposed changes to Chapters 4–8. Keep in mind that these proposed changes are just that—proposed. These changes could still be altered or removed by a public comment during the upcoming Comments stage of the code-making process. You have until Friday, October 23, 2009 (5 p.m. EST) to submit a comment on the proposed changes to NEC-2011. Read more

David Clements, IAEI CEO/Executive Director

by Rick Maddox

As the chairman of the IAEI CEO/Executive Director Search Committee, I am pleased to report the process of recruiting a replacement for James Carpenter is complete. While it has been a lengthy task of great importance to the association, the committee was committed to making a selection based on a dedication to the future of IAEI. Throughout the process, it was a pleasure to see so many people dedicated to the future of IAEI, as well as observing the quality of our membership. Read more

Have You Built Your…Investment Pyramid?

by Jesse Abercrombie

A few months ago I spoke with a very successful contractor about a trip that he and his wife made to see the pyramids and he spoke of the process of constructing the pyramids then versus now. Of the "Seven Wonders of the Ancient World,” the only one still in existence is the Great Pyramid of Giza. This tells you something about the strength of the pyramid structure, but it also suggests that the pyramid may be a good metaphor for other endeavors that you wish to endure — such as your investment strategy. Read more



The Power of U8

by Richard Owen

Membership. There, I said it! Now, please don’t roll your eyes and go to the next article, because you really need to think about IAEI membership—your own and your fellow members of this organization. Read more

Canadian Code

Resistance Grounding and Rule 10-814

by Leslie Stoch

This article looks at Rule 10-814 and the bonding conductor sizes given in Table 16 as they apply to resistance grounded systems. We’ll review the question—are the Table 16 minimum wire sizes appropriate when maximum available ground faults are limited by resistance grounding, or are there any circumstances when bonding conductors might need to carry larger fault currents? Read more

Canadian Perspectives

Are we ready for electric vehicles?

by Ark Tsisserev

After a well-known fiasco of the 1990s, electric vehicles are making a rapid and confident comeback. They are here to stay and to change our lives. Are we ready for them? Let’s take a look. Section 86 of the 2009 edition of the Canadian Electrical Code has been revised to clarify that an electric vehicle charging equipment must be supplied by a dedicated branch circuit. Read more

UL Question Corner

What types of emergency lighting are listed by UL under the product category Emergency Lighting and Power Equipment (FTBR)?

by Underwriters Laboratories

Luminaires that are specifically for use as emergency lighting are listed under the product category Emergency Lighting and Power Equipment (FTBR), located on page 142 in the 2009 UL White Book. Luminaires listed under (FTBR) would be evaluated for compliance with the Standard for Safety for Emergency Lighting and Power Equipment, UL 924. Read more

UL Question Corner

Can the wiring of normal and emergency power circuits be intermixed in luminaires?

by Underwriters Laboratories

I have an installation of a series of ten, row-mounted, 2 by 4 fluorescent troffer luminaires listed as surface-mounted fluorescent luminaires. They are provided with two circuits integral to the luminaire and also with wiring harnesses to connect those two circuits from one luminaire, end-to-end to another in a row-mount application. Every third luminaire is on the emergency lighting circuit. One of two circuits in the luminaire is connected to the normal power circuit and the other is supplied by the emergency power circuit. Do these rows of luminaires count as one emergency luminaire? Read more

UL Question Corner

Manufacturers explain that modifications were made to meet specific customer requirements, or for some unknown reason, the UL Mark or markings were not applied at the factory. What is UL’s position on this practice?

by Underwriters Laboratories

UL requires markings to be on UL Listed and Classified products constructed under UL’s Follow-Up Services (FUS) Program before they leave the factory. If a product is altered or a label is added after it leaves the factory, there is no way that UL can discern whether the product still complies with UL requirements without an evaluation. In such cases, UL conducts a Field Inspection. Read more

Recent Issues

September-October 2009July-August 2009May-June 2009March-April 2009January-February 2009

By Issue Date:
By Section