Aluminum Building Wire - 30 Years of Reliability
The cost benefits of modern aluminum conductors are backed up by three decades of reliability equivalent to copper.
Today, controlling building wire costs is more important than ever - but some building wire buyers are overlooking the easy economy of aluminum conductors. "In many feeder and branch circuit applications, aluminum delivers a significant edge over copper wiring in material cost," says Brian McCardel, Southwire Director of Construction Products.
For the last 30 years, aluminum alloys and connector technology have delivered reliability equivalent to copper - at about half the cost of equivalent copper products.
1960s aluminum wire was older 1350 alloy
Some buyers are still reluctant about aluminum building wire because of problems that occurred in the 1960s. At that time, materials costs were driving an industry-wide change from brass connector bodies and screws to steel. The change created temperature expansion problems with the electrical-conductor (EC) grade 1350 alloy then used in aluminum conductors. The actual problems lasted only a few years, and were resolved by the introduction of modern 8000 series aluminum conductor alloys.
Today's conductor alloys are a different breed
Modern aluminum building wire technology began in 1968, when Southwire introduced the first 8000 series aluminum alloy - Triple E®. Triple E is a proprietary alloy with the designator 8176. It combines high conductivity with mechanical characteristics that are much closer to copper than earlier EC-grade aluminum materials. Since 1987, the NEC has required an 8000-series alloy product in most building wire applications.
Triple E conductors also reduce pulling forces around bends. In most common sizes, Triple E requires about the same - or less - bending force as the equivalent capacity copper conductor. A few years ago, Southwire introduced its AlumaFlex® conductors using Triple E alloy that is specially annealed to make it even softer and easier to work with.
Connectors meet stringent load standards
Connectors have also changed since the late 60s. Since 1970, UL has required that all connectors used with aluminum be listed for that use - and the UL listing test is stringent. Both Triple E and copper conductors successfully meet the UL test requirements. EC-grade 1350 aluminum does not. For connectability, Triple E conductors provide safety and reliability comparable to a copper system.
30-year track record confirms reliability - and cost savings
We now have 30-plus years of experience with improved aluminum alloys and connectors. Over that time, aluminum and copper conductors have shown the same reliability when installed properly.
"And the cost benefits that made aluminum building wire popular in the first place are still there," says McCardel. "Southwire's Triple E and AlumaFlex conductors provide material cost savings over copper, plus lighter weight for easier handling. Those materials and labor cost reductions - with reliability equal to copper - make a powerful business case for aluminum building wire in many applications."
|THHN/THWN-2||#6 AWG - 1,000kcmil||Services, feeders, and branch circuits in commercial or industrial applications||Heat and moisture resistant polyvinyl chloride (PVC), with nylon or UL-listed equal jacket 90ºC, wet or dry; 70ºC when exposed to oil or coolent|
|XHHW-2||#8 AWG - 1,000kcmil||Services, feeders, and branch circuits in commercial or industrial applications||Abrasion, moisture and heat resistant black cross-linked polyethylene.(XLP) 90ºC, wet or dry|
|SE, SEU, SER||#8 AWG - 4/0 AWG||Service drop to meter base, meter base to panel board||Two-conductor with bare ground, three-conductor with bare ground and four-conductor with bare ground.|
|RHH or RHW-2 or USE-2||#8 AWG - 1,000kcmil||Underground service entrance cable, for direct burial||Abrasion, moisture, heat, and sunlight resistant black cross-linked polyethylene (XLP). 90ºC, wet or dry|
|Mobile Home Feeder||#2 AWG to 4/0 AWG||Connecting mobile homes where permanent wiring is required||Three-conductor plus ground; Suitable for direct burial at conductor temperatures not to exceed 90ºC.|