Steve,
What you have appears to be a classic inrush current failure of a 
tantalum capacitor. High dV/dt of the voltage across the cap flexes the 
dielectric layer due to its electrostrictive nature and if there are 
inclusions in the thin dielectric (~10nM) a small crack can result 
rapidly  increasing leakage current. Depending on the flaw size and 
resulting current, localized Joule heating can convert the dielectric 
film to an electrically conductive crystalline state and can easily 
overwhelm the healing or scabbing effect of an MnO2 cathode or depend on 
localized destruction of polymer in that cathode system.

I suggest that you check the manufacturers data sheet and expect to see 
a recommended series resistor measured in Ohms that was probably not 
used in the design.

I really loved tantalum capacitors when I was a consultant.

John Maxwell

>Yay it's Friday!!!
> 
>Well, I did all my grocery shopping yesterday so I could hole-up in my
>apartment this weekend to sit out the ice storm we're gonna get here.
>The temperature this morning was 65 F. when I got up this morning for
>work 5-hours ago, now it's 30 F.. It's supposed to eventually get down
>in the teens and we're supposed to get freezing rain starting in a few
>hours and lasting until Sunday. I hope we don't lose power...
> 
>Anyways, one of our test technicians came to me just a little while ago
>and told me he got the bejeebers scared out of him this morning. This is
>why:
> 
>http://stevezeva.homestead.com/files/Holy_Sh_t.jpg
> 
>It would have scared me too. Don't know why this happed yet...and yes,
>the part was installed correctly.
> 
>-Steve Gregory-
>
>  
>

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