Photo of aluminum to aluminum wire splicing before repair Aluminum Wiring Fire Hazards With Aluminum to Copper Twist-on Connectors & Acceptable Aluminum Wiring Repair Practices

  • US CPSC meeting on aluminum electrical wiring hazards 9/28/1995
  • Contents of US CPSC presentation on aluminum electrical wiring connectors, hazards, performance
  • Color photos describe aluminum electrical wiring fire hazards
  • Conclusion of the Aluminum Wire Repair Practices Presentation to the US CPSC

InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers, products, or services discussed at this website.

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.

Aluminum Wiring Repair Methods: Aluminum to Copper Twist-on Splices - CPSC Meeting 9/28/95 - Index to Contents, Presentation Conclusion

Aluminum Wiring Repair Procedure - Page 2 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.

This 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.

The CPSC presentation on aluminum wiring included conclusions that are given at the bottom of this page.

Green links show where you are. © Copyright 2015, All Rights Reserved.

William H. King, Jr. Manager       October 10, 1995
Div. of Electrical Engineering
U.S. Consumer Product Safety Commission
4330 East West Highway  Rm. 611 North
Bethesda MD, 20814

Subject: Meeting 9/28/95, Twist-on splices, aluminum to copper wire.

Dear Mr. King:

Enclosed per your request is a color copy of the slides used in my presentation at the subject meeting. Descriptive captions have been added to convey the significance that the slides had in the context of the meeting. An index by
subject is as follows:

Each aluminum wiring repair step listed below provides text, photographs and captions for those slides.

  1. Copper Pigtailing, instructions and illustrations, Slide #'s 1-3
  2. CPSC copper pigtailing test failures, examples, Slide #'s 4-7
  3. Additional test failures, basic 2-wire splice Slide #'s 8-9
  4. Examples of field failures Slide #'s 10-16
  5. Failure to make adequate wire-to-wire metallic contact Slide #'s 17-19
  6. Equivalent circuits, general case and newly made Slide #'s 20-23
  7. Current flow in steel spring, newly made connections Slide #'s 24
  8. Aluminum wiring connection deterioration process and consequence Slide #'s 25-27
  9. Why the UL High-Current Cycle test is inadequate Slide #'s 28-29
  10. "Special Service" aluminum wiring connector failures (similar standard) Slide #'s 30-32
  11. The AMP TYCO COPALUM crimp connector repair recommended by CPSC, illustration of the procedure, Slide #'s 33-34
  12. Alternative Repair Method: Special installation method for twist-on copper pigtail splice with aluminum wire, Slide #'s 35-49 - an alternative aluminum wiring repair method useful when the AMP TYCO COPALUM repair method is not available
  13. Special Concern - shell and inhibitor ignite/burn readily Slide #'s 50-55

    Please contact me if there are any questions.
    Yours truly,
    (original signed by)
    Jesse Aronstein, Ph.D., P.E.

Alumnum Wiring Presentation Conclusions

  1. The Ideal #65 "Twister" connector will fail in significant numbers in residential long-term service in the aluminum wire pigtailing application.

  2. The failure mode involves overheating, where, at normal operating current, the steel spring becomes red hot.

  3. Both the shell and the oxide inhibitor inside the connector ignite readily and burn freely, increasing the fire hazard substantially when failures occur.


Frequently Asked Questions (FAQs)

Click to Show or Hide FAQs

Ask a Question or Search InspectApedia

Use the "Click to Show or Hide FAQs" link just above to see recently-posted questions, comments, replies, try the search box just below, or if you prefer, post a question or comment in the Comments box below and we will respond promptly.

Search the InspectApedia website

HTML Comment Box is loading comments...

Technical Reviewers & References

Publisher's Google+ Page by Daniel Friedman

Click to Show or Hide Citations & References