What’s the Deal with Federal Pacific and Zinsco Breakers?

Insurance companies are increasingly requiring policyholders to replace Federal Pacific Electric (FPE) and Zinsco breakers as a condition for renewing policies, due to safety concerns. Independent testing has shown high failure rates in these breakers, posing risks of fire and power outages, and replacement is recommended to avoid loss of insurance and ensure safety.

FPE was a very inexpensive and popular brand of electrical equipment that was used extensively in the ‘50s, ‘60s, and ‘70s. It has been since it was discovered in the 1970s that FPE committed fraud in the conductance of the U.L. testing of their circuit breakers. Through legal wrangling, FPE managed to keep most of the failed test results of its defective breakers confidential.

FPE marketed its breakers under the name “Stab-Loc,” with three types of pole configurations. The 1-pole breaker is used on 120-volt circuits, the 2-pole configuration is used on 208- or 240-volt installations, and the 3-pole configuration is used for 3-phase 208-volt installations. Recent independent testing found that 40 percent of 2-pole FPE Stab-Loc breakers were defective and will not operate properly, and 8 percent will not trip under any condition. Of those tested, 75 percent of 1-pole breakers failed to trip at 135 percent of the rated current, with 25 percent that did not trip at all. The breaker needs to trip at or before this point to keep the insulation on the wires from overheating and causing a fire.

Zinsco breakers have a similar problem, though not as pronounced as FPE. Limited testing on Zinsco breakers showed a 28 percent failure-to-trip at 135 percent of rating, with 6 percent that did not trip at all. Additionally, these breakers have a defective connection to the panel bus that causes overheating and catastrophic failure inside the panel.

FPE and Zinsco breakers will inevitably need to be replaced, whether it is because the equipment will eventually fail, or because insurers will require replacement to renew the policy, or simply out of an abundance of caution for the resident. It seems prudent that a project of this size should be planned and executed before it becomes an emergency.
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What’s the Deal with Federal Pacific and Zinsco Breakers?

Some insurers are telling policyholders to change out all Federal Pacific Electric Co. (FPE) and Zinsco breakers as a condition of renewing insurance. This sounds relatively easy, but it definitely is not. So, what’s the scoop on this requirement? Is it a real concern or just manufactured hype?

HIDDEN FAILED TEST RESULTS
FPE was a very inexpensive and popular brand of electrical equipment that was used extensively in the ‘50s, ‘60s, and ‘70s. It has been since it was discovered in the 1970s that FPE committed fraud in the conductance of the U.L. testing of their circuit breakers. Through legal wrangling, FPE managed to keep most of the failed test results of its defective breakers confidential.

NOT MUCH IMRPOVEMENT
FPE marketed its breakers under the name “Stab-Loc,” with three types of pole configurations. The 1-pole breaker is used on 120-volt circuits, the 2-pole configuration is used on 208- or 240-volt installations, and the 3-pole configuration is used for 3-phase 208-volt installations. Recent independent testing found that 40 percent of 2-pole FPE Stab-Loc breakers were defective and will not operate properly, and 8 percent will not trip under any condition. Of those tested, 75 percent of 1-pole breakers failed to trip at 135 percent of the rated current, with 25 percent that did not trip at all. The breaker needs to trip at or before this point to keep the insulation on the wires from overheating and causing a fire.

NEWER DOESN’T MEAN BETTER
Some companies have tried to capitalize on this situation by manufacturing new breakers listed to fit in these old panelboards. Marketed as American, Federal Pioneer, Challenger, Federal Pacific Reliance Electric, UBI, Federal Pioneer Ltd., and Connecticut Electric, these replacement breakers have a similar or even higher failure rate than the originals. The reason for this similarity in failure is that the design of the case is essentially the same as the original failed design.1

Zinsco breakers have a similar problem, though not as pronounced as FPE. Limited testing on Zinsco breakers showed a 28 percent failure-to-trip at 135 percent of rating, with 6 percent that did not trip at all. Additionally, these breakers have a defective connection to the panel bus that causes overheating and catastrophic failure inside the panel.

DON’T RISK A TRIP FAILURE
Fire is not the only thing that puts your building at risk. There is a very good chance a building could be left without power for several weeks. There is a tendency for these old breakers to not reset after a trip or after an intentional shutdown. This may not be a big deal if it’s the breaker to an individual appliance that could be offline for two weeks, but what if it is the building’s main breaker? Can the occupants of the building live without power for two weeks until a replacement breaker is located? We have two clients who have found out the hard way that these old breakers often cannot be reset. In one case, several apartments were without power for two weeks and the occupants had to be relocated to a hotel.

AVOID LOSS OF INSURANCE
So, what does all of this have to do with insurance? Well, up until now, nothing. These breakers have been installed for over 50 years, and unless there is an overload or short that causes a catastrophic failure, most would not realize the true danger of these faulty breakers. But insurers are running out of money and are getting pickier about what they will insure, so do not just ignore them if this issue does come up. By not doing what the insurer demands, they may and often will decline to renew.

Last year around this time there was a big scare that buildings without fire sprinklers were losing insurance and being forced into the surplus lines. This dire warning was being used to persuade buildings to opt into installing fire sprinkler systems at costs of tens of millions of dollars. Now, even buildings with fire sprinklers are being non-renewed by insurers.

BY THE CODE
What should you do? Regardless of what insurers say, these breakers pose a risk to condominiums and other facilities. This is a legitimate safety issue that should not be ignored. For smaller equipment like the box inside a unit, Eaton manufactures a retrofit panel interior kit to replace the entire assembly inside the old box. This is a great alternative to changing the entire panel box; however, many panels are in closets and cabinets that do not meet the National Electrical Code (NEC) space requirements. Any retrofit would trigger the need to follow the 2017 NEC, so the space requirements would have to be met. If relocation of the panel is required because of working space requirements, it makes more sense to put in an entirely new panel.

As for the larger equipment that feeds the entire building, the only alternative is to replace the electrical system. This sounds horrible, but the upside is that it allows the opportunity to add system capacity for air conditioning and electric vehicle charging stations.

TAKE CONTROL
The main takeaway from this is to be in control of the timing of your power system replacement project. FPE and Zinsco breakers will inevitably need to be replaced, whether it is because the equipment will eventually fail, or because insurers will require replacement to renew the policy, or simply out of an abundance of caution for the resident. It seems prudent that a project of this size should be planned and executed before it becomes an emergency.

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