Federal Pacific
We apologize up front about the extent of this page and it's rather boring information about the hazards of having a Federal Pacific Load Center.  To save you time and headache, from having to read all this.  It is our policy at 2 Wire Electric Inc. NOT to add circuits or work on existing branch circuitry in a home that has a Federal Pacific load center.  The liability of doing work in homes that have these type of panels, is to great a risk.  These panels fail!  We don't want to be held responsible for any damages that may occur.  Our recommendation is to have then replaced as soon as possible.

The Bad & The Ugly


Introduction to the Federal Pacific Electric Stab-Lok Equipment Hazard


Supposing the circuits in your home were fed by a fuse box, with screw-in (Edison base) fuses. You may have seen these in some homes. You may also know about the common (but unsafe) practices of over-fusing (installing a higher-amperage fuse) or putting a penny in the fuse socket behind the fuse itself. These actions were taken to deal with the nuisance of fuses frequently blowing on overloaded circuits, or to deal with the lack of a spare fuse. Now, let's assume that an inspector notes some over-fusing and pennies behind some fuses, and waves the warning flag that it is a hazardous condition - a "safety defect". Inspectors, electrical contractors, and even realtors would agree that these conditions constitute a hazardous condition and should be corrected immediately. Red-flagging the Federal Pacific Electric ("FPE") Stab-Lok® panel is essentially the identical warning; it is the exact equivalent of having more than 1/3 of the circuits over-fused and/or with pennies behind the fuses.


Failure to trip properly under overload and/or short circuit is the basic safety defect of the FPE breakers. For example, if an overload or short circuit occurs in the clothes dryer or the circuit feeding it, the breaker is expected to trip open to minimize the resulting fire hazard. But, if it is an FPE Stab-Lok® two-pole breaker, extensive testing (by FPE, CPSC, UL, and others) has demonstrated that it cannot be depended on to trip properly. In the CPSC tests, a substantial portion of the FPE two-pole Stab-Lok® breakers, the type that would feed the dryer circuit, failed to operate properly. A significant portion of them jammed and would not trip at all, no matter what overload current was applied. Additional test data shows that there are also problems with the FPE Stab-Lok® single-pole breakers and combination breaker/GFI units.


This type of safety defect becomes important if and when there is a short circuit or substantial overload in the downstream circuit. Most breakers in a home are never called upon to trip, and the homeowner's perception is that "the breakers work fine". The same observation could generally be made if there were no breakers (or fuses) at all, just a hardwired system. In the event of an electrical malfunction, however, our safety may depend on proper operation of the circuit breakers.


In my own home, only two of the breakers have ever tripped during more than a quarter-century of our occupancy. I know nothing about the ability of any of the others to function properly, except that they are a brand and type that has not been identified as having any significant performance problems. There is no data suggesting that I should be concerned about their ability to function properly. With FPE breakers, however, there is a significant amount of test data and other information available that indicates a serious problem.


Additionally, there are safety problems in many of the FPE panelboards (panels), in which the breakers are installed. Some of the most common FPE Stab-Lok® panels are failure-prone due to marginal interconnections between the current-carrying components. The failing interconnections overheat at high current loading, and, in the worst case, fire ignites within the panel.


Details regarding both the FPE Stab-Lok® circuit breaker and FPE panel performance problems are provided in the following sections.� The bottom line is this: based on the information that is available and the testing that has been performed, there is no question but that homeowners need to be alerted to this safety defect and advised to have it corrected. Unless the occupant is willing to live with the risk, the FPE Stab-Lok® panels should be replaced.


In the 1980 time frame the U.S. Consumer Product Safety Commission (CPSC) investigated the performance of FPE Stab-Lok® full-width double-pole circuit breakers in ratings from 30 Amp to 80 Amp. One hundred and twenty two of these breakers were tested for CPSC (at Wright-Malta Corp.) to the Underwriters Laboratories' (UL) criteria, which included tests at 135% and 200% of rated current. The breakers should trip (open the circuit) at these currents within a specified time, with the current applied to either one pole or both poles. The two-pole breakers are essentially two single-pole breakers ganged together with linked handles, and they may or may not have an internal "common trip" mechanism, which is intended to assure that tripping of one pole causes both poles to open. Older FPE Stab-Lok® two-pole breakers do not have this feature.






For the test at 135% of rated current, 51% of the breakers failed with individual poles tested, and the failure rate was 25% with both poles tested simultaneously. The failure rates increased to 65% and 36%, respectively, after 500 operations of the on/off toggle handle.

For the test at 200% of rated current, the failure rate was 1% on individual poles tested, and 0% with both poles tested simultaneously. The failure rates increased to 10% and 1%, respectively, after 500 operations of the on/off toggle handle.


From an electrical safety standpoint, the most significant hazard identified in these CPSC-sponsored tests is that many of the two-pole FPE Stab-Lok® breakers may jam when trying to trip from overcurrent on one pole. This is due to mechanical friction in the common trip mechanism. Once the circuit breaker jams, its contacts will remain closed no matter what the current loading. This is serious -- a total failure that disables the protective device for that circuit. Essentially, the jammed breaker is exactly analogous to the "penny behind the fuse". This type of failure occurred in about 10% of the two-pole breakers.


The balance of the overcurrent failures are similar to "overfusing". For instance, a 30-amp breaker, which is normally expected to trip somewhere above 30 amps and below 40.5 amps (the UL 135% test point), actually doesn't trip until 44 amps. The 30-amp breaker is essentially a 40-amp breaker. This is analogous to the condition of "overfusing" -- perhaps not as dangerous a failure as a totally jammed breaker, but nevertheless generally considered to be an unsafe practice.


Federal Pacific Electric and/or their parent company Reliance Electric investigated their own circuit breakers and notified CPSC) of problems associated with their two-pole Stab-Lok® residential breakers. They have never made public any test data or technical reports on the 2-pole or any other breakers in their line. Recently, a homeowner reported that when he called FPE he was told that FPE had performed the same tests (as CPSC), but no details regarding the test results were provided. When the homeowner asked for the test results, he was told that they did not have them.


Test Results

Type of Breaker


No-trip Failures @135% of rated current


FPE Single-Pole, 1/2 Width




FPE Single-Pole, Full Width




FPE Single-Pole, GFI/Breaker




FPE Double Pole, 1/2 Width*




FPE Double Pole, Full Width*








Even if it were possible to replace all of the suspect FPE Stab-Lok® breakers with a more trustworthy type, that would not correct hazardous internal failure modes intrinsic to many of the FPE panels. Five of the seventeen FPE Stab-Lok® panels in the present study showed evidence of internal overheating due to this type of failure. The overheating ranged from mild to severe in these failing panels.

The "panel" is the unit within the enclosure, on which the breakers are mounted. The main electrical service feeders (electrically live, from the meter) are connected at the panel, and the panel has an internal conductor system that distributes the power to the individual circuit breakers. The internal conductor system consists essentially of "bussbars" (thick metal bars) that have sockets incorporated or attached, into which to which the breakers' "stab" contacts are inserted. There are at least three basic types of bussbar constructions in FPE panels.


A. Copper buss bar

B. "Z" clip, clamped to

C. Stab socket on a post, punched openings.


Of the three types, C. has the highest probability of deteriorating and overheating of the stab socket structures when subjected to significant current flow. Each individual stab socket plate is connected to its bussbar via a post (spacer), and the assembly is held together by an 8-32 steel screw. FPE panels with this construction are prone to overheating failure. The five panels of the present study that showed evidence of serious overheating were constructed this way.






In about 1978, the Consumer Product Safety Commission started a project on circuit breakers. CPSC worked together with the National Bureau of Standards (NBS, now NIST), to develop equipment that would allow the testing of breakers in place in a home. Some in-home measurements on various brands, including FPE, were made prior to mid-1980.

In mid-1980, Reliance Electric Company, FPE's parent company, notified CPSC of problems with the FPE two-pole Stab-Lok® circuit breakers. Shortly thereafter, a complex legal tangle began involving several companies, including Exxon, Reliance, UV Industries, and Sharon Steel, centering on allegations of fraudulent practices by FPE. See Reference 6 (copy attached) for some of the details as reported at the time. It is reported that, according to Reliance Electric, UL "delisted" virtually the entire line of FPE circuit breakers.

In 1981 CPSC initiated a specific test program on FPE two-pole Stab-Lok® breakers. The results clearly demonstrated that a significant number failed the UL standard tests, and that some would jam with the contacts closed on individual pole overcurrent conditions.  There was no basis for disagreement by FPE/Reliance as to the nature of the defects, but they claimed that there was no safety hazard associated with the defective circuit breakers.

In early 1983, CPSC closed its investigation of FPE breakers, and issued a press release to that effect.9 The Commission's press release indicates that it was "unable at this time to link these failures to the development of a hazardous situation," that "The Commission staff believes that it currently has insufficient data to accept or refute Reliance's position," and that they did not have the money to develop the required data.

Two important events had occurred prior to the Commission's vote that no doubt influenced their decision. In 1981, President Reagan took office. The political climate under the new administration was very much pro-industry, and CPSC was on the chopping block from a budget standpoint. The Commission did not have - and was not likely to get - the funds required for a protracted technical and legal battle with FPE/Reliance.

Equally important as background is that, in early 1982, CPSC lost a major battle in court on another electrical product - aluminum wiring. Kaiser Aluminum had challenged CPSC's jurisdiction over house wiring, claiming that it was not a consumer product. After a seesaw series of court decisions and appeals, Kaiser ultimately prevailed. Irrespective of any demonstrated hazard, the final ruling was that CPSC did not have jurisdiction unless it could prove that a substantial percentage of new home buyers contracted directly with the electricians for the installation of the wiring. That is generally not the case. It is much more common to have the electrician working under contract to the builder or general contractor. After spending a significant portion of their energy and budget on that project over a period of about eight years, CPSC had to abandon their case on aluminum wiring hazards due to that ruling.

In terms of the contractual relationships in home construction, the service entrance panel is analogous to the aluminum wiring. The Kaiser appeal could serve as a model for FPE. No matter what level of hazard CPSC might be able to demonstrate associated with the defective Stab-Lok® breakers, they had a high probability of losing if FPE chose to challenge their jurisdiction over the product. A precedent had been set in the aluminum wiring case.

CPSC has not been involved in the FPE circuit breaker issues since then. Their technical documentation is available through the CPSC's Freedom of Information Act Office.

The legal tangle involving Exxon, Reliance, FPE, etc., was eventually settled, with very little information made public. Most of the court records from that case are sealed. FPE was out of the circuit breaker manufacturing business by 1986, but the company continues today in the United States only as a legal entity. The contact address is an attorney's office.

In Canada, Federal Pioneer (Schneider Canada) manufactures Stab-Lok® circuit breakers and panels. A recall was announced (by Schneider and The Ontario New Home Warranty Program) of two of their 15-Amp models manufactured between mid-1996 and mid-1997. The announcement states that "In some circumstances these breakers may not trip. ... If the circuit breaker does not perform as intended, there is potential for property damage and/or personal injury." (Note: I have included this item because of the quote, which reflects a proper concern for electrical safety, and it is not intended to imply any broader problem with the Federal Pioneer Stab-Lok® line.)

In the 1990's, The emergence in of the internet as a practical means of information retrieval and exchange has resulted in increased attention to the FPE Stab-Lok® circuit breaker performance problems. As a positive result of internet communications, information on the problem has been made widely available, failure reports are being accumulated, and samples from homes are being made available for testing. As a negative result, a marketplace for used FPE Stab-Lok® breakers and breaker/gfi's has emerged. Given the data presented in the previous sections of this report, the purchase of used FPE Stab-Lok® equipment is risky.

In 1999, attempting to counter adverse information posted on the internet regarding the FPE Stab-Lok® breakers, an article was written for the IAEI News (the monthly publication of the International Association of Electrical Inspectors). The author of the article is not identified except as "the former quality manager of FPE, who is a consultant to the company ...", and the article contains a disclaimer that the information that it contains "is neither approved nor disapproved by the International Association of Electrical Inspectors."

The IAEI article does not provide any details regarding the nature of the circuit breaker performance defects and malfunctions that had been uncovered by the FPE, CPSC, and other testing; it only points to UL "listing and labeling" as indicating that they are OK. In its summary, it says, "The gist of this article is that FPE Stab-lok® load centers and circuit breakers are listed and labeled, and suitable for the usage intended." The article does not mention the fact that UL essentially de-listed virtually the entire FPE line of circuit breakers for a period of time, nor does it deal with the question of possible fraud related to obtaining and maintaining their UL listings and labels.

The anonymity of the author together with the disclaimer regarding IAEI agreement with the article's content make this article very unusual among articles in IAEI News. Nevertheless, electrical inspectors, having read the article in their own professional organization's publication, are likely to reflect the article's position when dealing with inquiries on this subject.




If I inspected your own home and found that it had a fuse box with 1/3 of the circuits over-fused or with pennies behind the fuses, how long would it be before you had it corrected? Would you sleep tight without it being corrected? Would the fact that your house had not had any problem (burned down yet) because of the over-fusing and pennies influence your decision as to whether or not to take corrective action?

Unlike over-fusing and pennies behind the fuses, defective FPE breakers cannot be spotted by an inspector or tested by an electrician or homeowner. Without doing a functional test (at overload and short-circuit conditions) on each breaker, one pole at a time for the two-pole breakers, one cannot actually determine the present operating characteristics of a breaker.

Most electricians or electrical inspectors can only look at the breakers ("they look OK to me"), and operate the toggle ("they click on and off OK"). But without doing live-current functional testing on all of the breakers, it is impossible to determine which of the breakers in the panel are defective. Will they all trip properly on electrical overload or short circuit? Electrical contractors and inspectors are generally not equipped to do that type of testing, and homeowners or potential purchasers are not likely to have the required budget for

extensive specialized testing. In fact, thorough testing would most likely cost far more than changing the panel.

The presence of an FPE panel in a home should be classified as a "Safety Defect". The FPE breakers are primary safety devices of questionable operating reliability. It is not quite correct to call the non-tripping breaker a "fire hazard". That term should be reserved for the electrical failure that causes ignition. >The breaker's function is to stop certain electrical sequences that could, if allowed to proceed, lead to fire in the building. If an electrical fire hazard develops somewhere in the building, the breaker is supposed to trip and minimize the possibility of fire ignition. If the breaker is defective, fire is more likely to result.

There is no question that the FPE STAB-LOK® panels should be replaced. There is no practical and safe alternative.


The Good

Sorry, nothing to report except they CAN be replaced!