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This document discusses the safety of older, "Pre-1970" Federal Pacific Stab-Lok Circuit Breakers & Electric Panels in buildings. It is information for building inspectors, home buyers, home owners, electricians exploring the background of possible hazards associated with Federal Pacific Electric Stab-lok circuit breakers and service panels.

Safety warning: while opening the hinged door provided for consumer use to access and reset the breakers is permitted, because there is risk of dangerous or even fatal electric shock in any electrical panel interior, only an expert should actually remove the front cover.

Readers should see SUMMARY OF the FPE Stab-Lok PROBLEM, also see the FPE Stab lok identification photos listed at FPE Stab Lok IDENTIFICATION, including FPE BREAKER LABELS.

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Safety of Older FPE Stab-Lok Electrical Panels & Breakers

Question: Are pre-1970 FPE Stab-lok circuit breakers as unsafe as the later models?

As I searched InspectAPedia I see statements that ALL FPE breakers and panels must be replaced. However the vast majority, if not all of the problem reports that I have read are of FPE circuit breaker equipment installed in the 1970's early 1980's.

We live in a neighborhood built in the 1950's and my wife is a realtor. The houses here have the old 100amp brown FPE breakers with copper split busses. Is there data and problem reports that supports a higher than normal industry failure rate for 1950s manufactured FPE breakers and panels? Or is this a "guilty by 1970s association so all FPE breakers and panels are bad" thing.

-- Loren Schiele. BS EE

Answer:

The photos below, courtesy of electrical panel researcher David Carrier, show older FPE Stab-Lok circuit breakers that include the use of some copper components. This 40-Amp two-pole circuit breaker, FPE Catalog No. 240, lacks an internal common trip mechanism, relying on mechanical linkage between the two breaker halves. Additional photos of FPE Stab-Lok circuit breakers of various vintages including this pre-1970 set are at FPE BREAKER ID PHOTOS.

Only Limited Testing of Older Pre-1970 Equipment

Among the more than 1600 FPE Stab-Lok breakers tested to date, there are too few of those with the "old" construction (brown case and/or hexagonal handle) tested to date to conclude that they are substantially different in performance.

Lack of Common Internal Trip Mechanism in Older Circuit Breakers

One significant difference is that the early 2-pole FPE Stab-Lok breakers had linked handles but lacked an internal common trip mechanism.

The lack of a common-trip mechanism is today considered less safe, which is why the standards were changed to require it. At the same time, these do not have the jamming problem of the later FPE 2-pole breakers that is specifically attributed to the common trip mechanism.

Degradation of Electrical Equipment With Age

The FPE Stab-Lok performance problems were not restricted to the 1970's and later production. While one could postulate that the quality control, tooling, etc. at the plant degraded with time, so that the early FPE Stab-Lok breakers might be better than the average FPE, that is in part balanced by the fact that mechanical devices generally degrade with time, and the original FPE Stab-Lok breakers are now headed toward 60 years in service.

There is also the question of added circuits and replacements.

Many of the original panels are likely to have some Stab-Lok breakers of more recent manufacture.

What is their performance?

Where do you get "good" Stab-Lok breakers for future additions or replacements?

Busbar Contacts in Older FPE Stab-Lok Panels

As for the busbar contacts, there are no problems that we know of with the original copper busbar (with openings punched in) and the heavy "stab" of the full-width breakers.

The split bus design (if that is what you have, as mentioned in your EMail) has adverse safety issues, however, regardless of brand of electrical panel involved.

Further Study Needed on Older FPE Equipment

If there are enough interested and cooperative homeowners in the neighborhood, perhaps you could organize a rotating breaker substitution system that would allow Dr. Aronstein or our collaborating test engineer David Carrier to test the breakers and return them, so as to obtain the performance data that all of us are interested in.

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FPE Stab-Lok HAZARDS & REPAIRS WEBSITE

• Thanks to reader Loren Schiele, BS in Electrical Engineering, for discussing older FPE Stab-Lok equipment and its safety concerns - M1y 2010
• Dr. Jess Aronstein, electrical engineer, Poughkeepsie, NY, forensic engineering services, independent laboratory testing for various agencies protune@aol.com (independent electrical panel testing, including FPE Stab-Lok panels, to April 2010)
• David Carrier, electrical engineer, 53 Henmond Blvd., Poughkeepsie, NY 12603 845-430-7527

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• The Federal Pacific Stab-Lok Electric Panel Hazard Website Safety Information for Consumers.
• 2007 FPE Stab-Lok TECHNICAL REPORT - an updated test report of independent testing (a large 1.2MB PDF file) using a larger pool of FPE Stab-Lok circuit breakers than the older CPSC and Wright Malta tests found significantly higher failure rates of FPE Stab-Lok circuit breakers, including a look at critical safety failures (breaker failed to trip at 200% of rated current or jammed) which found up to 80% failure rate for FPE Stab-Lok GFCI circuit breakers (n=4), 12% failure rate for double pole FPE Stab-Lok circuit breakers (n=120), and a 1% failure rate for FPE Stab-Lok single pole circuit breakers (n=345).
• FPE FIRES: Failures continue: FPE breaker fails, results in fires: field reports
• Federal Pacific Electric Fires Waiting to Happen, Debate Waiting to Be Ended, detailed article
• Home Inspection Reporting Language and discussion for FPE panels
• Home Inspection Reporting Language and discussion for FPE panels
• How to Identify FPE Federal Pacific Stab-Lok Electric Panels - is yours one of these? ALSO: A History of the FPE Stab-Lok Issue.
• Federal Pacific Electric Panels: Fires Waiting to Happen, Debate Waiting to Be Ended
• How to Identify Federal Pacific Electric Panels Stab Lok Breakers & History of the Federal Pacific Electric Stab Lok Hazard
• Replacement Circuit Breakers for FPE Stab-Lok Electric Panels? are not recommended
• Replacement Panels for FPE Stab-Lok load centers - options include conventional complete panel replacement and a less costly replacement of the panel interior load center/bus assembly
• Schneider Canada Federal Pioneer circuit breaker recall
• 1983 CPSC Investigation of FPE Circuit Breakers Safety Information for Consumers
• 1982 Reliance Electric Co. SEC Quarterly Report: Note C. reports litigation between Reliance and UV Liquidating Trust and contends that "... improper and deceptive practices were employed for many years to secure UL listings for Federal Pacific's circuit protective products..."
• 1980 Reliance Electric Co. Press Release: improper practices used to obtain UL Listing for most of FPE's circuit breakers and notes testing which indicates "possible defects." 1980, Reliance Electric Co.
• 1980 FPE - Exxon Buys A Scandal Along With A Company improper practices used to obtain UL Listing for most of FPE's circuit breakers and notes testing which indicates "possible defects." 1980, Reliance Electric Co.
  
  
• Safety Hazards and Safe Inspection Procedures for Electrical and Home Inspectors at Residential Electric Panels
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