Aluminum Wire: Copper Pigtailing Failures on CPSC Test, Examples InspectAPedia®  -     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.

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 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.

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4. Burnouts like this occurred when various UL-listed twist-on connectors were tested for the pigtailing application, installed as per the manufacturers' instructions. Poor test results for twist-on splices with aluminum wire were reported by UL, Battelle, CPSC, and various wire and device manufacturers.

5. The fire hazard posed by these splices when they fail is easily seen when the "burnouts" are observed while passing current. At about 17 amps, less than the 20 Amp rating of the (#10 aluminum wire) circuit, the connector spring is red hot. The voltage drop is about 2 volts, so downstream loads operate normally.



6. Additional red-hot twist-on connector splices fr6m the CPSC tests are shown here. The key point is that a significant percentage of the CPSC test splices over a period of several years failed in this hazardous manner, the spring becoming red hot. The connector shells ignited (smoldering combustion).



7. These tests were all conducted within rated service conditions. Applied current never exceeded 90% of the circuit rating (based on aluminum wire size used). The twist-on connectors used were UL listed for the application, and were installed as per the manufacturers instructions.

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Aluminum Wiring Repair Methods - CPSC Meeting 9/28/95
  Contents
  Copper Pigtailing
  Pigtailing failures
  Additional failures
  Field Failures
  Wire-to-wire Contact
  Equivalent Circuits
  Current Flow
  Connection Deterioration
  UL Test Inadequate
  "Special Connector" Failures
  AMP TYCO COPALUM
  Alternative Repair
  Special Concerns
ALUMINUM WIRING HAZARDS & REPAIRS
Aluminum Wiring Repair-
-Methods - CPSC Meeting 9/28/95
Aluminum Wire Risk
Reduce the Risk
Repair Details
DIRECTORY OF ELECTRICIANS - Aluminum Wiring
DIRECTORY OF ELECTRICIANS - FPE Zinsco
Other Products
Detailed Article

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• Our recommended books about building & mechanical systems design, inspection, problem diagnosis, and repair, and about indoor environment and IAQ testing, diagnosis, and cleanup are at the InspectAPedia Bookstore. Also see our Book Reviews - InspectAPedia.
• The Aluminum Wiring Information Website Aluminum Wiring Hazards and Repairs: in-depth info, photos, documents. Main Page.
• The Aluminum Electrical Wiring Hazard Explained (in the document you are presently viewing)
• How to Reduce the Risk in Buildings with Aluminum Electrical Wiring - Overview of Acceptable Repair Practices (in the document you are presently viewing)
• Aluminum Electrical Repair Method Details - "How to" details, how to identify, COPALUM repair, alternative repairs, history, products, research, source of special AMP TYCO COPALUM connectors & COPALUM Electricians (in the document you are presently viewing)
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• The Aluminum Wiring Bibliography: extensive resources on Aluminum Wiring
• Aluminum Wire Failure Reports & Photos: Real life aluminum wiring field failure reports
• Reducing the Fire Hazards in Aluminum-Wired Homes, Jess Aronstein, Ph.D., This document answers most technical questions about the hazards and remedies of aluminum electrical wiring. Some of the sections of this very thorough document are listed below:
• Fire Hazards With Aluminum to Copper Twist-on Connectors & Acceptable Aluminum Wiring Repair Practices Color Photos, Current Issues. 9/28/95 CPSC Meeting Minutes
• "Is YOUR Aluminum Wiring Safe?" article discussing safety claims made by some people without looking at the wiring, J. Aronstein, 11/21/95
• "Repairing Aluminum Wiring," U.S. Consumer Product Safety Commission Publication CPSC#516 available online
• * Safety Hazards and Safe Inspection Procedures for Electrical and Home Inspectors at Residential Electric Panels
• Electrical Panels, How to Inspect in Buildings, safety for electrical inspectors, electrical panel, fusing, wiring defects, defective products. Inspection Class Presentation
• Electrical System & Wiring Hazard Inspection, Detection, Cause, Remedy, Prevention - Main Electrical Page
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