Selection Criteria for Residential Aluminum Connections

Abstract

Suitable permanent connectors are required for use with branch circuit aluminum wire in homes. Some connection devices that have been marketed as suitable for use with aluminum wire are prone to deteriorate with time under conditions of normal use, leading to instances of hazardous overheating. The literature and experimental evidence discussed in this paper soundly support the position that, from a safety standpoint, the only acceptable aluminum connection devices for permanent residential installation are those that show no resistance increase under both normal and accelerated test conditions.

Evaluation of a twist-on connector for aluminum wire

“…[81 There are several major reasons for this, including small sample size, lack of environmental testing., and liberal pass/fail criteria. [13] Most important for this application, however, is that; 1) the qualification tests do not require testing of the splices througlh the aluminum-to-aluminum current path, 2) the splices are not mechanically stressed during the qualification testing as they are in actual installations (by the action of inserting completed splices into junction boxes), and 3) the aluminum wire used for the qualification testing is an alloy conductor rather than the EC aluminum that exists in most residential installations. (The alloy aluminum conductors were developed to have improved performance relative to the EC grade aluminum conductor in a heat-cycle test using binding-head screw terminals.…”