FPE breaker failed to trip - this is a typical breaker side blow-out that occurs.FIRES WAITING TO HAPPEN - Federal Pacific Electric Panels
Fires Waiting to Happen, Debate Waiting to Be Ended

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

Why are FPE - Federal Pacific Electric circuit breakers and electrical panels unsafe?

This document explains the latent electric shock and fire hazards associated with Federal Pacific Electric Stab-Lok® electric panels and circuit breakers and in Challenger® electrical panels and circuit breakers. Federal Pacific Electric "Stab-Lok® " service panels and breakers are dangerous and can fail, leading to electrical fires. The problem is that some 240-Volt FPE circuit breakers and possibly also some 120-Volt units simply may not work.

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.

Green links show where you are. © Copyright 2017, All Rights Reserved.

How Many FPE Stab-Loks Are There? Why Are They Still In Place?

It has been suggested that there are as many as 28 million of these FPE Stab-Lok® breakers in use in the U.S. which means that in some conditions as many as one million of them may fail to provide proper fire protection. This includes "new old stock" and appears to include "substitute" FPE Stab-Lok® circuit breakers, none of which have shown an improvement in reliability in independent testing. So the right "repair" is to replace the FPE Stab-Lok® electric panel.

But where are they? Most homeowners whose houses are served by these panels are unaware of the hazards. So too are some inspectors and contractors.

Because most homeowners do not order periodic electrical safety inspections, the presence of these panels is often undiscovered until an inspection made in the course of renovating or selling a property. Our field experience indicates that even when problems occur with this equipment, often it is simply removed or replaced with little publicity. Neither manufacturers nor some electricians are inclined to frighten consumers.

See HOW to IDENTIFY FPE Federal Pacific Stab-Lok® Electric Panels - is yours one of these?

What is the FPE Stab-Lok® Failure Rate and How Much Worse Is It Than Other Equipment?

FPE Stab-Lok® or Federal Pacific Electric Stab-Lok® circuit breakers can fail to trip at an alarming rate. In the original testing, at a modest overload (135% of rating) switches that had never been touched (never mechanically switched) were energized on both poles. These failed 25% of the time, followed by a lockup that meant the switch would never trip in the future at any overload. Once these switches had been flipped on and off (mechanically energized), failures increased to 36%!

Worse, when individual poles on these switches were energized under the same conditions, 51% of the "virgin" switches failed, and for switches that had been mechanically energized, a whopping 65% of them failed!1

In the most recent independent tests of FPE Stab-Lok® equipment, 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). (To download this article see "Technical Reports" below.)

When a circuit breaker will not trip in response to an overload there is a serious risk of fire.

What is the Proper Repair for FPE Stab-Lok® Panels and Circuit Breakers?

Homeowners and renovators who encounter these panels should replace the entire panel and circuit breaker set with new equipment. Panel replacement, can involve significant expense, typically $800 to $1200 depending on service size and other factors.

Do not simply replace individual FPE Stab-Lok® circuit breakers: first of all, there is no data suggesting that new stock, replacement FPE breakers, or "new old stock" FPE breakers found in storage somewhere perform any better than the ones already in the FPE Stab-Lok® panel. Second, there are other functional and safety concerns in the panel besides the breakers themselves. We've seen panel bus damage, panel bus meltdowns, and failure of breakers to remain secured in or onto the connecting bus itself.

Replacement Federal Pacific Electric FPE Stab-Lok® Circuit Breakers

For several reasons I do not recommend attempting to "repair" an individual failed Stab-Lok® breaker by buying a replacement either from used stock, new stock, or "compatible" stock:

In sum, if you could replace all the FPE Stab-Lok® equipment with (somehow magically obtained) all "new" FPE Stab-Lok® equipment (found in a used-or new-old-stock warehouse for example) the risk level for the building would not be sufficiently different from before the replacement and would remain high: there remains a latent risk of fire from failure of these breakers to trip in response to overcurrent.

Replacement Federal Pacific Electric FPE Stab-Lok® Panels is Recommended

For some cost and method alternatives when replacing an Federal Pacific Electric Stab-Lok® Panel or "load center"
see REPLACEMENT PANELS which describes conventional Option#1 - "remove and replace" the electrical panel and Option#2 - FPE Load Center Replacement using Cutler Hammer (CH) Adjustable Retrofit Kit

See FPE REPLACEMENT BREAKERS for details about and advice against replacement circuit breakers sold for retrofit or installation into Federal Pacific Electric Stab-Lok® electrical panels.

Reader Discussion & Comments about the FPE Stab-Lok Hazard & Challenger Electric Panels, Breakers, & Field Failures

Question: Thanks for the FPE warning

(Aug 21, 2011) TX Homeowner said:

I've just learned about the FPE Stab-Lok panels and although, after having the panel for 50 years and having no problems until today, I am replacing the panel and all breakers tomorrow. It will cost $2,000 but if it saves the life of me and my family, it's worth it. Thanks for the warning.


Thanks for the feedback TX homeowner.
Indeed, if your electrical system never experienced an overcurrent, nothing ever called on a circuit breaker to trip. Having breakers that fail to trip when they should at a rate of up to 60 % of the time is like riding around in a car with the seatbelt cut nearly thorough. Everything's just fine as long as you're not in an accident.

Kudos for being safe.

Best wishes

Question: I want to replace the whole unit - is there financial help?

(Nov 5, 2011) ME Homeowner said:

Appreciate the info! Our FPE box with stab-lok breakers has been in place since the house was built in 1980. We are lucky in that we have never had any issues, and all the breakers have worked perfectly, even up to today. I would be interested however, in replacing the whole unit, but the expense would be way too much for me right now (primarily the labor costs). Is there any chance that these units have such a bad reputation that my homeowners insurance might recognize this and step up to help me with the costs?


ME please see these two articles

Question: difficult to remove FPE panel

(Jan 26, 2012) Eric Doute said:

Id like to comment that this is also one of the hardest panels to get out of the wall. They have a 1/2" lip that sits recessed in the wall causing you to botch and cut it out with extreme predudice. I had a big 200amp tall boy I had to rip out. It also had laminated plywood wall surface. This may add an hour or two to the job if its recessed into the wall. Also you have to be careful of not hitting any wires with the sawzaw. If you do the work yourself, make sure you pull out the meter before you start any cutting to risk hitting live wires.


Eric, I appreciate the warning about difficulty removing an FPE Stab-Lok electrical panel but I suspect that the removal problem ou describe has nothing to do with the panel design in this case. Rather the issue is how your particular electrical panel was installed p with a lack of working space. Still, understanding the trouble one may run into when replacing any electrical panel helps understand the cost of hiring a professional to do the job.

Question: Why do I find replacement FPE breakers only on E-Bay?

(Feb 11, 2012) Bryan Skruck said:

I just bought a rental property that is 40 years old with one of these panels. I noticed that because of the design that the breakers aren't secure in the panel and that is what I believe has caused the panel bus damage. I seem to have the opposite problem with the breakers tripping prematurely a 12.5 A load trips a 20 A breaker (again, I think it has to do with the design and the poor contact between the breaker and the panel bus)

I was wondering why I couldn't find these breakers anywhere except on e-bay. I was going to add a diishwasher but it looks like there's another more important project first. I'll have to make sure none of the circuits are overloaded myself since there seems to be a substantially high rate of breakers failing to trip.

In an effort to not completely discredit the load center itself and Federal Pacific, part of my problems have stemmed from improper breaker installation. There is a wiring diagram on the panel that shows breaker sizes at pole locations. Each panel has spaces that accommodate either full size (NA style) or 1/2 size (NC style) thin breakers.

It appears that the installing contractor decided to use thin style breakers throughout, either because he was in a hurry and didn't have any full size breakers on hand at the time of installation, or didn't follow directions. I'm pretty sure this wasn't the doing of a homeowner after the fact because the way the panel is laid out. My problems are occurring where the thin style breakers were used in a full size breaker space. Those are the ones that are loose and arching. The panel bus is now damaged, so the entire box must be replaced. I realize there are other problems with the breakers not tripping when overloaded as well, but my problem with arching and premature breaker tripping was due to improper installation.

Was wondering about the picture posted at the top of the article. Clearly that breaker suffered water damage as indicated by the rusted rivets at the top. If water is leaking into your electrical panel, you’re going to have a problem!


Bryan, there are vendors of replacement circuit breakers for FPE Stab-Lok electrical panels, discussed and warned-about

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.

Question: defective FPE breaker without popping?

(Apr 21, 2012) Dennis said:

Can beaker be defective with out popping. reason just replaced one
The circuit would cut out hour or more then come back on.
Replaced breaker problen went away.


Yes Dennis, there are other hazards including

Question: buying a house with and FPE Stab-Lok panel

May 2, 2012) Paul Scott said:

Good Evening, thinking of buying a house, it has the FPE Stab-Lok panel. My inspector pointed it out, and we advised the seller. Her response was that she has lived in the house for 25 year and hasnt had a problem! so, seeing how these panels are not "ilegal" , explaining to her that it could be an issue is hard.

She was living alone for these years or with her husband so possible there wasnt a load on the system. However i will have 3 kids and two adults! if she doesnt agree to fixing this, if i put GFI outlets in the bath rooms will this at least help in the shock department?? if you have anything i can use to persuade the seller please let me know


Paul, in my opinion the cost of replacing an electrical panel is such a tiny part of the value of a home that it certainly ought not to deter a home buyer. And it should be replaced.

As we comment in various FPE articles, absence of evidence of a "problem" may simply mean that the breakers were never exposed to an overcurrent, so were never called-on to trip. It's also the case that there may be already-jammed circuit breakers in the FPE panel that simply haven't been noticed by anyone if no one has tried to work on a supposedly switched-off circuit.

Adding GFCI's in an older home reduces shock hazards but will not address the no-trip problem back in the electrical panel.

Question: if I replace the FPE panel do you think the building is safe?

(June 27, 2012) Cathy - Westchester NY said:

There is a Federal Pacific Electric Stab-Lok Panel in the co-operative apartment that I'm intested in purchasing. Even if I replace the box do you think the building itself is safe?


Cathy, I am GUESSING that you mean that you're worried that other FPE Stab-Lok panels remain in place in your building. My opinion is, I agree with the implication of your question: replacing your panel reduces the electrical fire risk significantly within your co-op apartment, and thus somewhat reduces risk for your co-owners; but until everyone replaces their panel, risks remain. Beyond that, no one in their right mind could possibly state, by email or by a web page comment, that a building then know nothing about is "safe" or "unsafe".

Question: Comment: multiple FPE panel flaws mean the panels should be replaced.

(Sept 3, 2012) Greg said:

Many of the FPE panels have other design flaws that create unnecessary hazards for those of us who have to service them. Many of the breaker handles require you to push them toward the "on" position in order to remove them. They also used a bolt and nut to secure the dead-front panel, which becomes a problem especially since most of them are rusted by this point. The result is that the cover is rarely secured properly and presents a major shock hazard to the home owner.

This, along with the known fire hazards, should be plenty enough evidence to replace these panels as soon as possible. The design is poor and the breakers have several known problems. As and electrician, I assure you my first concern is safety. I remember being schooled as a young apprentice about the dangers of working on these panels, rightfully named "the widow maker". Replace it.

Question: is my FPE panel involved in the recall?

(Apr 3, 2013) Barbara Walters said:

Our house was built in 1986 and a Federal Pacific box was used (Y82647A-Rev.A),I don't see StabLok on the box but can you tell me if this unit would be in the recall?



Yes Federal Pacific was an earlier brand of the identical StabLok Design. Click to expand the Related LInks near page top to see a series of product identification articles.

There was no recall. The buyer of FPE took an allowance for a recall and decided to pocket the money.

Comments from Vendor of FPE Replacement Circuit Breakers

UBI Replacement circuit breakers sold for FPE replacement - 5-16-2014 incident report (C) 8, 2014) Mike said:

You do not have to replace your entire panel if you have Federal pacific Stab-lok style breakers. There is a company, Connecticut-Electric, Inc that makes brand new, ETL listed, same test as UL, circuit breakers that are safe to use and completely safety agency listed.

There seams to be a "red scare' out there about these breakers, yes, there were some issues. Even the federal government couldn't make a decision based upon the facts present to say that Federal Pacific breakers are actually unsafe. Why spend all that money replacing your entire panel, which most electrician love to hear. They just see dollar signs.


Watch out: 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.

(Apr 8, 2014) (mod) said:


I cannot imagine worse advice than your opinion stated below. There are several very serious concerns:

  1. the "replacement breakers" that you cite have no evidence of performing any differently than the unreliable ones they replace
  2. the underlying design problems that lead to breaker no-trips and bus connector burn-ups and on occasion more serious losses, remain when the panel remains
  3. In addition to having been found guilty of fraud, label switching, cheating on breaker qualification tests, and other improper practices, independent research has consistently shown that the product fails to respond to overcurrent at a stunning rate, in the 60% range for 2 pole breakers, in an industry where overall circuit breakers fail to trip in response to overcurrent at a fraction much less than 1%.
  4. FPE Stab-Lok electrical panels and circuit breakers are a latent safety hazard. That means that the product does not itself initiate a failure or fire. The breakers may also remain "on" internally when apparently switched off - a good way to electrocute someone. It's a latent safety hazard just sitting there, failing to protect when it's called upon in an emergency. That may explain why this "sleeping dog" while it remains asleep - not called on to perform - seems just fine. There's no need for panic, but there is a need to replace the equipment.
  5. On one point we might agree, that is that some electrical repair companies and product vendors indeed prey on consumer fear to make a buck. For this reason we point out that

WATCH OUT: One wonders who Mike is and what might be his connection with the company he touts.

Reader follow-up comments "Would you prefer that this escalated further? "

(Apr 9, 2014) Mike said:


You are correct, My position with Connecticut Electric is inside sales.

We make the UBIF line of circuit breakers, Which is a Federal Pacific REPLACEMENT circuit breaker that is ETL listed to the UL molded case 489 standard. We have been manufacturing for nearly 20 years the UBIF breakers, and have not seen an issue with the design or function.

You claims of unsafe, recalls, and fire hazards, etc are all based upon fiction. You are making false claims. Would you prefer that this escalated further?

Reply: Stating the FPE Hazard Accurately

(Apr 9, 2014) (mod) said:

Mike, with all due respect, and appreciation that you want to discuss this matter, you completely mis-state the CPSC position. The issue was not closed with a statement of absence of evidence. The history of the matter is that CPSC management, in negotiation with FPE attorneys decades ago, overrode their own engineers and the results of that work to decide to stop the investigation.

There is not a shred of doubt that the hazards are real. That information is supported by the CPSC's research, by very extensive independent research, and by decades of reports of serious failures, fires, and even a few fatalities.

Before you try threats or other silly action that could embarrass you, you should read the independent research in this matter.

Take a look at

The 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).

Also see


If you have independent research on the failure rates of FPE replacement breakers from various sources, we would be glad to see it and would be glad to add that to information for our readers to consider.

It would be great for consumers if there were a field repair for FPE equipment that addressed the breaker hazards, bus hazards, and that were supported by independent research.

Unfortunately, just plugging in a breaker from an unknown (or possibly even a known source some of which included both used and new old stock FPE breakers) into an existing FPE panel does not address the known hazards. To date, the effective repair that may be less costly than a whole new panel has been the installation of CH's replacement bus and breaker assemblies.® is an independent publisher of building, environmental, and forensic inspection, diagnosis, and repair information for the public - we have no business nor financial connection with any manufacturer or service provider discussed at our website.

We are dedicated to making our information as accurate, complete, useful, and unbiased as possible: we very much welcome critique, questions, or content suggestions for our web articles provided discourse is polite and informed. Threats from Mike (no last name provided) or his company are in my OPINION a poor substitute for unbiased data, research, and data.

Finally, Aronstein's research has been continued by another independent electrical engineering researcher, David Carrier who has added additional brands and breaker sources to the mix; to my knowledge that work is ongoing and additional results have not been released.

As Mr. Carrier has continued independent testing of circuit breakers for no-trip failures, if you are interested in providing [funding for an in-the-market-place purchase of ] some of your product for independent testing let me know and I'll check with David - I'd expect that he'd welcome a chance to have a source of new or old product for failure testing.

[Aronstein has pointed out the importance of testing circuit breakers that are obtained in the same market place in which consumers will purchase them, thus avoiding any suggestion that any manufaturer might have pre-tested, pre-qualified, or otherwise skewed independent test results with product supplied directly from its producer. ]


FPE - UBI Replacement Circuit Breaker Discussion Continued [with a vendor of replacement breakers]

(Mar 13, 2012) Anonymous said:

Dan, the one point that I find very confusing is why Schneider-Federal Pioneer Stablok panels and breakers have not been shown to have an elevated risk of danger--except for the relatively few breakers subject to the recall. If the stablok design is inherently dangerous, Federal Pioneer breakers should seize frequently enough to result in a "body count."

It does seem that the one FPE panel shown has buss corresponding to Jesse Aronstein's "Type C," direct insertion; is this the main difference? If so, does it reduce heating to a sufficient extent to a sufficient extent that the better environment overcomes any inherent inadequacy in the breaker design?

Also, when you describe Asian replacement stab-loks as similarly inadequate, are the breakers you tested NRTL-listed?

(Oct 2, 2012) Mike said:

Still have seen nothing regarding FPE Replacements, such as being made by American Circuit Breaker, except, "not recommended", "no evidence the replacement is any better", ect., and other opinions. The testing and research into FPE is extensive and proven. Why, as you have many resources available to minutely test the originals, do you rely on mere opinion and conjecture regarding the replacements. In my experience, I have seen none of the supposed problems with the so called "split buses" buses or other parts of the FPE panel, excepting wire bending radius inadequacies, so it seems a repacement of the FPE breakers with AMC breakers would work satisfactorily. AMC has been UL tested, and approved. They have not been proved to be unsafe.


Anon and Mike:

There are certainly field reports of FP failures from the Canadian product, but in point of fact we have very little data from the Canadian installations and too few tested breaker samples to support an unequivocal conclusion about their performance. However, in speaking with a Schneider engineer several years ago, it was made clear that there was no product redesign from the original defective FPE design. I asked Schneider where their manufacturing line equipment came from, figuring that perhaps the manufacture, testing, or QA were different from the offending plant(s) in the U.S. but the company appeared to get nervous and declined to offer further information.

Keep in mind that the FPE defects are a latent hazard - the breakers fail to respond properly to an overcurrent. If an overcurrent does not happen, no evidence of failure shows up. We do not have a study of differences in electrical wiring and installations between the U.S. & Canadian homes, nor a study of differences in frequency of overcurrent events - in particular, interruptible electrical ignition events in which a fire will be caused ONLY if the protection device is defective, improperly sized, mis-wired, tapered with.


I much appreciate the discussion, but with respect, your comments and conclusions about the safety of FPE equipment are simply incorrect. The articles found in this section draw from, quote, cite testing that has been performed through 2012.

And I think you'll find that we have documented that the FPE replacements are the identical design, in fact are generally, new old stock that was purchased from FPE. I have asked experts to keep us informed about any additional testing of FPE, FP (Canadian equipment now sold by Schneider) and of the replacement market products.

In fact as the article above cites and Aronstein confirms, testing included a limited number of replacement FPE circuit breakers. No-trip failures were encountered in that group as well.

Aronstein also points out that self-selection of product submitted for "independent" testing is itself problematic. At least in past experiences manufacturers first screened product to weed out failing devices before submitting the remainder for testing. And as you know from reading FPE history, there was still more serious test fraud occurring in the in-house tests.

Excerpting from FPE Stab-Lok® : FIRES WAITING TO HAPPEN where you also posted comments and where we provide more details, we cite:

What's needed is an amended circuit breaker test procedure that obtains breakers for testing from the open marketplace, from the very same sources that will be used by consumers and electricians when buying replacement circuit breakers.

Watch out: Finally, the fact that you have not personally seen "supposed problems", while it is an understandable reaction, is not sound. One individual's experience is hardly a technically sound approach to product evaluation. Or putting it in fancier language, absence of evidence in one person's personal experience is hardly evidence of absence of a problem. In fact we have both independent test results indicating no-trip failures and field reports indicating no-trip failures of these devices.


Notice: In subsequent discussion reader Mike acknowledged that he works in sales for Connecticut Electric, a vendor of replacement FPE circuit breakers - Ed.



Continue reading at FPE FIRES: FAILURE REPORTS or select a topic from closely-related articles below, or see our complete INDEX to RELATED ARTICLES.



Suggested citation for this web page

FPE Stab-Lok® : FIRES WAITING TO HAPPEN at - online encyclopedia of building & environmental inspection, testing, diagnosis, repair, & problem prevention advice.


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


Frequently Asked Questions (FAQs)

Click to Show or Hide FAQs

Ask a Question or Search InspectApedia

Questions & answers or comments about the latent nature of fire and shock hazards associated with Federal Pacific Electric FPE StabLok panels and breakers.

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

Comment Box is loading comments...

Technical Reviewers & References

Click to Show or Hide Citations & References

Publisher's Google+ Page by Daniel Friedman