[ale] [Slightly OT] What IS this electrical Component?

[Alex Carver]

On 12/29/2012 09:46, Neal Rhodes wrote:
> http://flic.kr/p/dFrXah should be a picture of the innards of a 120VAC
> to 24VAC wall wart.
>
> Which is somewhat obscure, and is now farschtunken.   (zero output)
>
> The big clue is infinite resistance across the 120V side.
>
> Tearing it apart, I'm seeing about 80 ohms across the primacy coil, and
> this little black thing, which shows infinite resistance both ways.
>
> I may just end up getting a replacement adapter, cutting off the cable,
> and splicing on the obscure connector, but I'm curious what this thing
> is.
>
> Writing on it says:
>
>
>          AUPO (rombus shape with some letters inside)
>          A 2-1 A-F jet
>          115<degrees-symbol>C  R1
>
>
> If I had to guess, then I'd guess it's some kind of thermal protection
> device that is normally conducting straight through, but opens up at 115
> degrees to protect from overload?
>
> Any thoughts on what this is, and if one could obtain a replacement part
> somewhere?

You are correct.  It's a 115 C thermal fuse made by Xiamen Electronics 
out of China.  Radio shack used to carry thermal fuses (used in coffee 
makers) many years ago right in the store.  Not sure if they do anymore 
but the electronic catalog has them listed as available for ordering. 
Otherwise Digikey, Mouser, or Newark/Farnell/Allied will have it.