Slide 31 Aluminum Wire: "Special Service" connector failures (similar standard)

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Failures in twist-on connectors used for aluminum wiring repairs: This article continues the discussion of the inadequacy of UL Standard 486C for twist on connectors if used for splicing aluminum to copper wires and adds that certain "special service" connectors sold for this purpose, such as the Purple twist-on connector shown do not perform well in this application.

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Aluminum Wiring repairs using twist on connectors supported by UL486C & that Standard are Inadequate

This is the Aluminum Wiring Repair Procedure - Page 10 Color photos and descriptive captions from CPSC Meeting 9/28/95. In this document aluminum wire twist-on connector failures and repair procedures are described, including aluminum wire repair methods which work and methods which do not work and are unsafe.

Color photos of aluminum wire repair procedures, and photos of failed connectors are included. This document series describes hazards with existing aluminum wiring repair products, explains the aluminum wiring failure mechanism, and reviews recommended retrofit procedures including use of readily-available materials.

This aluminum wiring safety information was presented to the US Consumer Product Safety Commission by Dr. J. Aronstein, 9/28/95. The minutes of that meeting were obtained under the Freedom of Information Act and posted by Daniel Friedman January 1996.

Slide 30 30. That testing of the type applied by UL486C is inadequate has previously been demonstrated by the Canadian "Special Service" twist-on connector.

These were qualified by tests essentially the same as UL486C, but performed poorly in long-term tests within rated conditions. This one is starting to overheat.

Slide 31 31. This special service connector splice has overheated to the point of softening the wire insulation.


Slide 32 32. This special service twist-on splice between aluminum wire and stranded copper wire burned up.

Details are at IDEAL-65 Purple Twister and at ALUMINUM WIRING REPAIR NOT-Recommended


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