Free Encyclopedia of Building & Environmental Inspection, Testing, Diagnosis, Repair
Ask a Question or Search InspectAPedia
InspectAPedia ® Home
ELECTRICAL INSPECTION, DIAGNOSIS, REPAIR
ACCURACY vs PRECISION of MEASUREMENTS
AFCIs ARC FAULT CIRCUIT INTERRUPTERS
ALUMINUM SECs & WIRING
ALUMINUM WIRING HAZARDS & REPAIRS
AMPS VOLTS DETERMINATION
AMPACITY - the LIMITING FACTOR
APPLIANCE EFFICIENCY RATINGS
BACKUP ELECTRICAL GENERATORS
BOOKSTORE - ELECTRICAL
BUILDING SAFETY HAZARDS GUIDE
Cadet & Encore Heater Recall
CIRCUIT BREAKER FAILURE
CIRCUIT BREAKER SIZE for A/C or HEAT PUMP
Classified CIRCUIT BREAKER WARNING
CORROSION in ELECTRICAL PANELS
CORROSION & MOISTURE SOURCES in PANELS
CUTLER HAMMER PANEL FIRE
DEFINITIONS of ELECTRICAL TERMS
DIRECTORY OF ELECTRICIANS
DMM Digital Multimeter, How to Use
ELECTRIC METERS & METER BASES
ELECTRIC MOTOR DIAGNOSTIC GUIDE
ELECTRIC MOTOR OVERLOAD RESET SWITCH
ELECTRIC PANEL AMPACITY
ELECTRIC PANEL INSPECTION
ELECTRIC PANEL MOISTURE
Electric Power Frequency Table
EMF RF FIELD & FREQUENCY DEFINITIONS
ELECTRICAL GROUND SYSTEM INSPECTION
ENERGY SAVINGS in buildings
FEDERAL PACIFIC FPE HAZARDS
FIRE SAFETY Checklist, CPSC
GFCI PROTECTION,Testing GFCIs AFCIs
HEATING COST FUEL & BTU Cost Table
HEAT TAPE USAGE GUIDE
Hertz - Definitions of KHz MHz GHz THz
KNOB & TUBE WIRING
LIGHTING, EXTERIOR GUIDE
LIGHTING, INTERIOR GUIDE
LIGHTNING PROTECTION SYSTEMS
LOW VOLTAGE BUILDING WIRING
LOW VOLTAGE TRANSFORMER TEST
MAIN DISCONNECT AMPACITY
MOISTURE SOURCES in PANELS
MURRAY SIEMENS Recall
PHOTOVOLTAIC POWER SYSTEMS
PUSHMATIC - BULLDOG PANELS
REMOTE ELECTRIC POWER, PHOTOVOLTAIC
RUST in ELECTRICAL PANELS
SAFETY for ELECTRICAL INSPECTORS
SE CABLE SIZES vs AMPS
SIEMENS MURRAY Recall
UNDERGROUND SERVICE LATERALS
VOLTS / AMPS MEASUREMENT EQUIP
WIND ENERGY SYSTEMS
WIND TURBINES & LIGHTNING
ZINSCO SYLVANIA ELECTRICAL PANELS
Aluminum electrical service entry cables (SECs): This article summarizes possible safety and functional concerns with the use of aluminum wiring for service entry cables or electrical panel components in buildings, and provides a link to the aluminum wiring information website. This is a chapter of our discussion of the inspection of electrical services at buildings in order to determine service capacity in volts and amps. Readers should also see ALUMINUM WIRING HAZARDS where we provide complete detail about aluminum electrical wiring hazards.
Green links show where you are. © Copyright 2013 InspectAPedia.com, All Rights Reserved. Author Daniel Friedman.
ALUMINUM SECs & WIRING - Aluminum Service Cables and Wiring in buildings for Electrical Service Delivery
In both branch circuit and entrance cable wires, the permitted wire gauges for copper are normally one size smaller than for aluminum used at the same ampacity rating. This is because copper is a better conductor than aluminum. Aluminum wire must be larger to safely carry the same current as copper.
Fire and Safety Issues with Aluminum Electrical Wiring
There are important fire safety issues concerning the presence of aluminum branch circuit wiring in buildings - not discussed in this article. Solid aluminum branch conductors are no longer used in new wiring.
Aluminum service entrance cables and aluminum single-purpose high-amperage circuits [NOTE: Such as for auxiliary sub-panels, central air conditioning or electric ranges.> are commonly installed in many communities.
Photo (left) contributed by an anonymous reader, shows multiple aluminum SECs and main disconnects at an apartment building bank of electrical meters.
Many new electric service panels use plated aluminum parts. According to some experts risks remain even with these permitted applications in both the US [see "Reducing the Fire Hazard in Aluminum-Wired Homes," Jesse Aronstein, Ph.D., Wright Malta Corporation, Ballston Spa, NY, 1982] and Canada [see "Overheating Failures of Aluminum-Wired Special Service Connectors," Jesse Aronstein and Wilfred E. Campbell, IEEE Transactions on Components, Hybrids, and Manufacturing Technology, Vol. 4 CHMT-6, No.1, March 1983.]
The risks of poor connections and fire hazards for aluminum SEC wiring are reduced by proper abrasion of the connected wires, proper tightening of the connector, and use of a special anti-corrosion flux compound.
As recently as June 2006 we received a report of a major house fire which the owner asserts began at an overheating electrical service entry cable connector.
Our OPINION is that because the number of these connections is less than on a branch circuit wire, and possibly for other technical reasons involving the performance of multi-stranded aluminum wire, the risk of a fire is probably statistically less than with solid conductor branch circuits. It would appear that the risk is not as low as with copper service entry cables.
Key References on Aluminum Electrical Wiring
The Aluminum Wiring Information Website for a thorough discussion of aluminum branch circuit wiring concerns in the U.S. and in Canada as well.
[There is disagreement among professionals about the Canadian risk and failure rate. Ontario Hydro and some Canadian inspection professionals do not acknowledge a significant risk from aluminum wiring in Canada. However the Scarboro development in Ontario demonstrated that failures and fires have occurred in that country. --DF]
Frequently Asked Questions (FAQs)
Questions & answers or comments about aluminum service entry electrical cables or wires: sizing, hazards, connections, burn-u.
Ask a Question or Enter Search Terms in the InspectApedia search box just below.
Technical Reviewers & References
Related Topics, found near the top of this page suggest articles closely related to this one.