Thread: Flyback fire
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Old 05-19-2008, 02:16 PM
RetroHacker RetroHacker is offline
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Join Date: Jan 2005
Location: Niskayuna, NY
Posts: 464
Quote:
Originally Posted by MRX37
It's kinda funny to me that they would use WAX and PAPER in a component that has the potential to arc and catch fire.
Actually, both of those materials are excellent insulators. And, remember, sixty years ago, modern synthetic epoxy resins did not exist.

Flybacks can catch fire, this is true. But, aside from making a lot of nasty smelling smoke, they shouldn't cause much else to catch fire. The chassis is made from metal. And I seriously doubt that a burning flyback would be able to make a large enough (or hot enough) flame to be able to catch the inside of the cabinet on fire.

A larger problem with the old wax and paper components (flybacks, capacitors), isn't so much that they could theoretically catch fire, but that they have a tendancy to be affected my moisture. The wax/paper combination is OK at sealing out moisture, but not as good as, say, plastic. The moisture gets into the component, corrodes/breaks down the dielectric properties of the materials, and the component fails.

Wax also melts fairly easily. So, if the flyback gets too hot (caused perhaps by a HO section drawing too much current), the insulating wax melts away, then a partial short forms - then you get an arc, and burning.

-Ian
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