InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers, products, or services discussed at this website.
This article discusses and compares the hazards of Federal Pacific Stab-Lok® Electric Main Electrical Panels compared with Sub-Panels in buildings, and addresses the question of amount of risk reduced if only the main disconnect or main FPE panel is replaced.
This information assists building inspectors, home buyers, home owners, electricians exploring hazards associated with Federal Pacific Electric Stab-Lok® circuit breakers and service panels.
Our page-top photo shows a main FPE Stab-Lok® electrical panel and service disconnect (at left) and three FPE Sub-panels.
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.
We also provide a MASTER INDEX to this topic, or you can try the page top or bottom SEARCH BOX as a quick way to find information you need.
Comparing the Hazard of Federal Pacific Stab-Lok® (FPE) Electric Sub-Panels vs. Main Panels & Main Disconnects
Our photo (left) shows an FPE Stab-Lok® main electrical panel. Multiple main disconnects are in the top section of the panel.
[Click to enlarge any image]
Question: Do FPE Stab-Lok® Sub-Panels Present as Much Risk as the Main FPE Panel?
A commercial insurance broker in the Western U.S. placed insurance on a hotel built in 1964.
In 2000 the Main Electrical Panel, an FPE Stab-Lok® unit, was replaced with a unit made by Murray.
The hotel includes nine remaining “sub-panels” made by FPE
The insurance company that we placed the hotel with has a policy that they do not accept properties with FPE panels.
Our question is: Do the FPE sub-panels present as much risk as the main FPE panel?
It seems in a perfect world the hotel would change out all sub-panels, but at least they have upgraded the “main” panel. Do you think this is an acceptable compromise? - (Anon.)
Reply: Replacing the Main FPE Panel reduced risk but significant risks remain with the FPE Subs. Here are some of the risk factors:
A competent onsite inspection by an expert usually finds additional clues that help accurately assess the actual electrical hazards that would not be included whatsoever in a theoretical discussion. For example there could have been a history of failures to trip, overheating, or unusual circuit usage on specific circuits serving particular areas of the hotel, or there may be other significant electrical hazards (or other hazards) outside of the FPE topic that also merit urgent attention.
That said, here are some things to consider in assessing the degree of risk that has been achieved by replacing only the main FPE electrical panel:
Replacing the main disconnect & panel did reduce risks: We agree that having installed another brand main panel has reduced the overall hazard for the building (if an FPE was in that role before), but
The absolute risk for a given or individual FPE sub-panel or breaker or a circuit wired from such a breaker actually depends in part on the circuit's usage. An FPE breaker does not initiate a hazard or failure - it simply fails to protect the circuit from overheating (and fire) if an overcurrent or similar hazard occurs. This behavior is detailed in FPE Technical Report - Independent Research 2007
Problem history: It is a dangerous error to presume that if no problem has occurred to date, the wiring and breakers are safe. A problem could have occurred previously that resulted in a much greater chance that at a subsequent overcurrent the breaker won't trip (that phenomenon was demonstrated in independent testing);
Changes in circuit use are not predictable: even if a problem never occurred on a circuit, simply a change in use (someone plugs in an electric heater) can and probably will change the risk level.
Risk for similar circuits in similar use: Our opinion is that for two circuits of similar level of usage, the hazard is similar, regardless of whether or not the circuit is wired out of a main or a sub panel.
Here too, hidden circuit differences, such as a poor connection, would change that picture.
Two Pole breakers: It would be fair to argue that because the FPE no-trip problem is more severe on 2-pole breakers, and as a main panel would have at least one 2-pole breaker (the mains) while a sub panel that contains less than 6 switches may not have a main switch and so may not have a 2 pole switch, then the absolute risk might be lower, but that is in my opinion a "constructed" and is too theoretical an argument to be safe - if for no other reason than it does not consider circuit usage.
Risk of incomplete electrical repairs: As a general opinion on electrical safety, we are very nervous about "partial" repairs of electrical hazards because of the risk that building occupants or management, thinking that an unsafe condition has been addressed, may ignore warning signs of an impending disaster.
In sum, the experience of insurers with FPE failures and perhaps their review of the research has indeed led some companies to ask that FPE panels be replaced.
Can't afford or need to stage-in FPE panel replacements? As a sub panel replacement is likely to be under $1000. that cost compared with a fire is surely small and reasonable. Some suggestions for people who cannot afford to immediately replace an FPE Stab-Lok® electrical panel are found at CAN'T AFFORD A NEW ELECTRIC PANEL?
Continue reading at FPE REPLACEMENT PANEL or select a topic from closely-related articles below, or see our complete INDEX to RELATED ARTICLES below.
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).
Carson, Dunlop & Associates Ltd., 120 Carlton Street Suite 407, Toronto ON M5A 4K2. Tel: (416) 964-9415 1-800-268-7070 Email: email@example.com. The firm provides professional home inspection services & home inspection education & publications. Alan Carson is a past president of ASHI, the American Society of Home Inspectors. Thanks to Alan Carson and Bob Dunlop, for permission for InspectAPedia to use text excerpts from The Home Reference Book & illustrations from The Illustrated Home. Carson Dunlop Associates' provides extensive home inspection education and report writing material.
The Illustrated Home illustrates construction details and building components, a reference for owners & inspectors. Special Offer: For a 5% discount on any number of copies of the Illustrated Home purchased as a single order Enter INSPECTAILL in the order payment page "Promo/Redemption" space.
TECHNICAL REFERENCE GUIDE to manufacturer's model and serial number information for heating and cooling equipment, useful for determining the age of heating boilers, furnaces, water heaters is provided by Carson Dunlop, Associates, Toronto - Carson Dunlop Weldon & Associates Special Offer: Carson Dunlop Associates offers InspectAPedia readers in the U.S.A. a 5% discount on any number of copies of the Technical Reference Guide purchased as a single order. Just enter INSPECTATRG in the order payment page "Promo/Redemption" space.
The Home Reference Book - the Encyclopedia of Homes, Carson Dunlop & Associates, Toronto, Ontario, 25th Ed., 2012, is a bound volume of more than 450 illustrated pages that assist home inspectors and home owners in the inspection and detection of problems on buildings. The text is intended as a reference guide to help building owners operate and maintain their home effectively. Field inspection worksheets are included at the back of the volume.
Special Offer: For a 10% discount on any number of copies of the Home Reference Book purchased as a single order. Enter INSPECTAHRB in the order payment page "Promo/Redemption" space. InspectAPedia.com editor Daniel Friedman is a contributing author.
Special Offer: Carson Dunlop Associates offers InspectAPedia readers in the U.S.A. a 5% discount on these courses: Enter INSPECTAHITP in the order payment page "Promo/Redemption" space. InspectAPedia.com editor Daniel Friedman is a contributing author.
The Horizon Software System manages business operations,scheduling, & inspection report writing using Carson Dunlop's knowledge base & color images. The Horizon system runs on always-available cloud-based software for office computers, laptops, tablets, iPad, Android, & other smartphones