Federal Pacific Electric was a company that make circuit panels. They developed a new type of breaker, and applied for approval from the United Laboratories. The UL turned them down.
They then built a different breaker and sought approval for that. That one did get approval.
The problem was, the new one cost more to manufacture, and the first one a lot less. So What did they do? They manufactured millions and millions of the first one, using the UL number from the second breaker! And if a whole bunch of them hadn’t caught fire, they might have gotten away with the swicheroo. But they did, and FPE got caught. And sued. And closed down.
I still see a few FPE panels a year, usually in houses built in the 1950’s. I don’t open them up. Apparently, the breakers have been known to fall out of the panel. Besides, What would I learn? my recommendation is still the same; have the panel replaced by an electrician.
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