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Finally figured out why my Zinsco panel kept tripping the main breaker
Had this old Zinsco panel in a rental house I was working on last week, kept popping the main every time the tenant ran the microwave and AC at the same time. I thought it was overload, but I checked the load calc and it was fine. Spent two hours chasing my tail until I remembered an old timer once told me Zinsco breakers don't trip the same as modern ones - they can weld shut. Sure enough, one of the branch breakers was stuck closed and feeding back. Replaced it and the main stopped tripping. Anyone else run into weird Zinsco gremlins that aren't the usual fire-hazard stuff?
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sagew5020d ago
FOUR TIMES I've had Zinsco breakers that looked perfectly fine but tested closed with a multimeter. That welding issue is no joke. I had a landlord once get all defensive when I told him his panel needed to go, saying "it's been fine for 30 years." I showed him a branch breaker that was literally melted into the bus bar and he went quiet real quick. Those things are TERRIFYING because they give zero warning before they fail.
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gavina7320d ago
That welded bus bar line gave me chills.
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