Aluminum Lugs

Dec 1, 2000 12:00 PM, By Kristine M. Rose

In the September issue of EC&M, you ran an article, "Copper or Aluminum Lugs: How Should You Decide?" written by John Paschal, P.E. I was disappointed by the article's bias against aluminum connectors. Although the article itself is neutral, the elements around the text (pictures, headlines, and highlighted text) are severely slanted toward copper connectors.

First, the opening image for the article was that of an oxidized, unplated aluminum lug. The caption claims "Wire joint failure is not far behind." If a reader scanned the magazine without reading the article, he or she would be left with a very negative impression of the safety of aluminum connectors.

In addition, the subheading to the left of the photo, reads "Does spending more money for copper lugs offer extra security and reduced maintenance?" Again, the reader is given a poor impression of aluminum connectors, which is counter to the content of the article.

Finally, the bold text in the article says "The review shows where electrical continuity really counts, `copper throughout' is most often the specification still today." Again, the scanning reader is left with the wrong impression, because the article concludes copper and aluminum connectors perform equally well in the proper circumstance.

The author referenced old, outdated manufacture methods of aluminum connectors. Users today are assured of quality parts to fit their needs.

The truth about the performance of aluminum connectors is that they perform very well over time. More importantly, a UL-listed aluminum connector is plated to reduce both oxidation and improve conductivity. Ilsco's UL-listed connectors, as well as other manufacturer's products, are plated. To quote the article, "the coatings impede aluminum oxide formation for long time - even in moisture-laden conditions."

Ilsco, as well as other aluminum connector manufacturers, recommends oxide inhibitor with all aluminum connections. This is not a UL requirement, but Ilsco strongly urges its use to impede oxidation. As the author wrote, with its use "galvanic action and oxide formation almost cease to be a problem."

Users purchase aluminum connectors for a variety of reasons. First, many aluminum connectors are dual rated for use with copper or aluminum conductors. This greatly increases flexibility in use.

Second, aluminum connectors are much less expensive than copper connectors. If cost is a factor in the installation, aluminum is preferred. Third, when the user purchases a UL-listed aluminum connector, the connector has performed to the stringent standards of UL, and so reliability is assured.

One had to read paragraphs into the article to obtain the facts: "(Aluminum-bodied lugs) statistically have no more failures than copper lugs. In fact, the only aluminum lug failures I found involved cracking of the sidewalls of the lug and threads of the setscrew during initial installation - the result of not properly using the required torque wrench." Even the author could not substantiate connector failure because of the material - proper installation (the use of torque wrenches and oxide inhibitor) avoids problems.

Kristine M. Rose
Product Manager, Ilsco

EC&M's Response:

Let me start by addressing your concern with the article headline: "Copper or Aluminum Lugs: How Should You Decide?" There is nothing in this title that suggests one material is better or worse than the other. Nor does the title, in any way, imply a user should choose copper over aluminum. It merely invites the reader to read the article to get an answer to the question. The title is meant to attract the attention of "old salt" electrical engineers, who have simply specified "ALL COPPER" for the last several decades - so they may have an open frame of mind to consider changing their view after reading supporting information.

Now, let's take a look at the deck: "Does spending more money for copper lugs offer extra security and reduced maintenance?" Once again, this is meant to make readers question their decision to use copper connectors instead of aluminum (which is exactly opposite of Ms. Rose's opinion). It's an invitation to read further into the article and learn the truth about this controversial subject.

Photo 1 and its caption are in the article to help explain why there's a misconception in the industry about the performance of aluminum connectors. It ties in well with the historical discussion of the development of aluminum connectors and reinforces the fact that an aluminum lug (previously made by one manufacturer) without the proper coating will form an oxide coating and eventually fail.

Although all of the lugs produced by manufacturers today do come with a coating (as Ms. Rose pointed out), there are many lugs like the one shown in the photo that are still in use today. As a service to the industry and our readers, we feel this is an important fact to bring up. It was our plan that this photo and caption would help reinforce the need to use a UL-listed aluminum connector with the proper coating, such as the type that you make, and that we show in Photo 2.

In looking at the pullquote on page 52, I agree someone scanning the article might get the wrong impression about the true entire content of the article. However, it's a fact that many industry participants do feel this way. That's why we decided to write an article on this topic in the first place. The information presented throughout the article helps to clear up some misunderstandings on the true performance characteristics of aluminum connectors.

Photo 2 was put in the article to help a reader understand the manufacturing steps used today to produce an aluminum connector. In fact, the author specifically told me that a chief engineer for Ilsco actually discussed this process with him in person and gave him this lug while on a visit to his office.

I believe this article presents an unbiased and objective analysis of this issue. While controversial topics sometimes raise concern among different segments of the industry, especially manufacturers, we still have to report on them to maintain our editorial integrity.

This service piece in no way slams Ilsco; nor did we run it to imply aluminum conductors are inferior. Instead, the article brings to question whether copper offers superior service (probably something the reader has long since taken as gospel), and then shows the reader that modern technology provides an aluminum product on par with copper.

Mike Eby
Editor-in-Chief, EC&M Magazine