Federal Pacific Electric Panel Tests Indicate Failures

Independent tests of FPE Equipment: October 15, 2000, Poughkeepsie, NY. Tests by an independent forensic engineer confirmed failures of circuit breakers in a Federal Pacific Stab-Lok® residential electric panel that was contributed by a homeowner.

Replacement FPE Stab-Lok® circuit breakers are unlikely to reduce the failure risk of this equipment. We recommend that residential FPE Stab-Lok® electrical panels be replaced entirely or the entire panel bus assembly be replaced, regardless of FPE model number or FPE year of manufacture. We do not sell circuit breakers nor any other products. 

Recent Federal Pacific Electric, Federal Pioneer & UBI Failure Test Results

Following a recap of where to find the most-recent FPE and FP Stab-Lok panel and breaker and replacement FPE breaker test results, we include the results of testing of an FPE panel contributed for independent reliability testing.

This test, a subset of the entire UL 489 Standard, is intended to determine proper electrical circuit breaker function in response to overcurrent.

40-Amp breakers were tested at 135% of rated load and should trip within an hour. 20-Amp and 15-Amp breakers were tested at 200% of rated load and should trip within 2 minutes.

Question: Where is the most-recent published data updating findings on the FPE Stab-Lok® ® Hazard?

I am writing to see if you have published data from the NJ condo study showing increased failure rate with FPE Stab Lok panels and breakers. - D.H., a NACHI home inspector in Washington State

Reply: Most-recent FP FPE UBI & related Circuit Breaker Failure Test Results & Field Failure Reports

D.H.

Thank you for asking about updated status on FPE (Federal Pacific Electric) Stab-Lok® ® hazards. Because of publication restrictions and rules imposed by IEEE, we have cited but not published the contents of the most important recent study that contains updated and authoritative research on the FPE hazard.

See most recent or particularly-useful FPE and related circuit breaker reports in the following pages:

• 2024 final report - HAZARDOUS FPE CIRCUIT BREAKERS AND PANELS - 2024 [PDF] independent research article by Jess Aronstein, supercedes older FPE / FP hazard reports by this author.
• 2022 - FPE FAILURE FIELD REPORTS [web article] includes field reports from about 1984 to the present
  
  Also see FPE FAILURE FIRE PHOTOS
• 2018 - UBI FPE CIRCUIT BREAKER TEST RESULTS [web article]
  Excerpt:
  
  Current results of overcurrent tests performed on UBI circuit breakers sold as replacements for FPE Stab-Lok circuit breakers: as of April 2017, testing of 420 UBI circuit breakers show overall a high failure rate of about 42% - higher than FPE circuit breakers, and significantly-higher than the performance of most other brands and designs of circuit breakers. In addition, two-pole UBI breakers frequently jam after which they will not trip at any level of overcurrent.
  
• 2018 - Jesse Aronstein ¹, (Life Senior Member, IEEE), & David W. Carrier ² MOLDED CASE CIRCUIT BREAKERS - SOME HOLES IN THE ELECTRICAL SAFETY NET [PDF] Received December 4, 2017, accepted January 24, 2018, date of publication February 7, 2018, date of current version March 15, 2018. Digital Object Identifier 10.1109/ACCESS.2018.2803298
  1 Consulting Engineer, Schenectady, NY 12309, USA, 2 SUNY Dutchess Community College, Poughkeepsie, NY 12601, USA, Corresponding author: Jesse Aronstein (AronsteinJ@verizon.net)
• 2017 - FPE HAZARD REPORT - 2017 [PDF] independent research article by Jess Aronstein, supercedes older FPE hazard reports by this author.
• 2011 - US Consumer Product Safety Commission Closes Investigation Of FPE Circuit Breakers And Provides Safety Information For Consumers, REVISED 18 Feb 2011 [PDF] The original document was revised to include the following warning:

  Note: CPSC staff advises electricians, homeowners, home inspectors and real estate agents to read and interpret the following press release carefully.
  
  The press release announces that the Commission closed the matter without making a determination as to the safety of FPE circuit breakers or the accuracy of the manufacturer’s position on the matter.
  
  The Commission advises consumers to take the safety precautions noted in this notice with all circuit breakers and fuses.
  
  You can obtain copies of this report from IEEE as well as copies of earlier or later studies.

  Jesse Aronstein, Ph.D., P.E., and Richard Lowry, Ph.D., "Estimating Fire Losses Associated with FPE Stab-Lok® ® Circuit Breaker Malfunction", IEEE ESW-2011-29, Industry Applications, IEEE Transactions on, Jan.-Feb. 2012,

  An updated version of the original paper, possibly available from Dr. Aronstein, identifies the name of the defective circuit breakers - information that was not identified in the published version due to conference rules. Abstract:

  Abstract - A method is presented for connecting small branch circuit breaker functional test data to statistical fire loss data. Test results are presented for field samples of a particular line of circuit breakers that have an abnormally high defect level.
  
  The test results are then utilized in combination with available electrical fire statistics to estimate the annual number of fires and consequent injuries, deaths, and monetary loss associated with the defective breakers.
  
  An estimate is then made of the reduction of injury and loss that can be achieved by encouraging replacement of the defective breakers. The role of the electrical safety community in promoting replacement of the
  defective breakers is discussed.

  In my OPINION the Aronstein/Lowry IEEE-published study is an important update on the FPE hazard. It establishes the FPE Stab-Lok® hazard to a new higher level of certainty across the entire product line, and concludes that "... there are substantial fire losses due to the defective operation of FPE Stab-Lok® (R) circuit breakers.

  The Aronstein/Lowry report found failure rates confirming those documented in earlier FPE Stab-Lok® studies and it cites the considerable body of failure data that has been produced since the CPSC closed its investigation in 1983. Importantly, Aronstein/Lowry also conclude that defects exist across the entire FPE Stab-Lok® ® circuit breaker product line (rather than just the specific breaker types originally investigated by the US CPSC).

  The study also recaps more recent legal history of the FPE Stab-Lok® breaker product, citing the 2002 New Jersey class action lawsuit in which the judge ruled that the manufacturer of FPE Stab-Lok® ® breakers committed fraud over a period of many years by applying UL-labels to circuit breakers that did not meet UL product testing standards.
  
  The decision drew principally on the company's own documents, but public documents also indicate that FPE lost their UL listing when deceptive testing and labeling of breakers was discovered (see our citation of press reports - FPE EXXON SCANDEL Article [web page] published at InspectAPedia.com).

  In sum, the recent Aronstein/Lowry study is a call-to-action to the U.S. CPSC to finally make a clear warning to both the electrical trades and the public concerning the FPE Stab-Lok® ® hazard.

• 2000 - 2000 FPE breakers fail in lab test of field-supplied panel 10/00 - found just below on this page
• 2008 - 2007 FPE Stab-Lok® TECHNICAL REPORT (revised) [PDF] an updated, faster-loading copy of the 2007 FPE circuit breaker 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). 
• 1982 - FPE FRAUD Stab-Lok® SEC REPORT - much older but worth noting.

Federal Pacific Electric Test Performed on Homeowner's FPE Breaker Panel

The breakers in this Federal Pacific Stab-Lok® panel were tested according to the Underwriters Laboratories UL Standard UL 489 calibration test.

This test, a subset of the entire UL 489 Standard, is intended to determine proper electrical circuit breaker function in response to overcurrent.

40-Amp breakers were tested at 135% of rated load and should trip within an hour. 20-Amp and 15-Amp breakers were tested at 200% of rated load and should trip within 2 minutes.

Federal Pacific Electric (FPE Panel) Test Results

The FPE panel tested contained 19 circuit breakers.

• 4 breakers (green tabs in various photos) performed properly: the breaker opened the circuit within the prescribed time and the toggle switch moved to the "tripped" position.
• 13 breakers (yellow tabs in various photos) did not work properly, demonstrating mechanical irregularities within the product: while all "opened" the circuit, some moved to the full-off position and others stayed in the full-on position.
• 2 breakers (red tabs in various photos), nominally "tripped" in that there was partial or full toggle movement. However, they failed to open the circuit on at least one pole.

10% (2 out of 19) of the Federal Pacific Electric Stab-Lok® breakers in the panel tested failed to perform properly. In the electrical industry, the failure rate for non-trip breakers is virtually zero.

Photographs of Federal Pacific Electric Panel Tested

• FPE PANEL after testing - oblique view - note variations in toggles after every breaker was subjected to overcurrent
• FPE breaker failure - did not open the circuit in response to overcurrent
• FPE breaker mechanical variations - this breaker moved to full "off" position after tripping - mechanically inconsistent with breakers which usually move to a "tripped" position
• FPE breaker - proper function - tripped properly after testing as described above
• FPE PANEL after testing - front view
• FPE PANEL identification label - from panel tested

...

Continue reading at FPE Stab-Lok® TECHNICAL REPORT or select a topic from the closely-related articles below, or see the complete ARTICLE INDEX.

Or see these

Recommended Articles

• CIRCUIT BREAKER FAILURE RATES - home lists circuit breaker failures, studies, across multiple brands
• CIRCUIT BREAKER RELIABILITY TESTS gives test results and no-trip failures for both older and newer FEP, FPE & UBI-FPE Circuit Breakers showing high failure rates also for some Murray and Crouse Hinds circuit breakers.
• FEDERAL PACIFIC FPE HAZARDS - home
• FPE FRAUD Stab-Lok® SEC REPORT
• HAZARDOUS FPE CIRCUIT BREAKERS AND PANELS - 2024 [PDF] Final Report - independent research article by Jess Aronstein, supercedes older FPE hazard reports by this author.
• FPE STAB-LOK HISTORY

Suggested citation for this web page

FPE Stab-Lok® MOST RECENT REPORTS at InspectApedia.com - online encyclopedia of building & environmental inspection, testing, diagnosis, repair, & problem prevention advice.

Or see this

INDEX to RELATED ARTICLES: ARTICLE INDEX to FPE STAB-LOK BREAKERS & PANELS

Or use the SEARCH BOX found below to Ask a Question or Search InspectApedia

Ask a Question or Search InspectApedia

Questions & answers or comments about tests on FPE Panels and Breakers.

	HOME	ABOUT	ASK a QUESTION	CONTACT	CONTENT USE POLICY	DESCRIPTION	POLICIES	PRINT	PRIVACY
	© 2026 - 1985 Publisher InspectApedia.com - Daniel Friedman