Sanken PSA10982J M Exploded Primary Capacitor

[mockingbird]

This PSU comes out of a Panasonic TC-20LA2 from around 2004. I repaired the inverter board by changing out one of the SOIC MOSFETs and a fuse a while ago thanks to information posted on this forum, but today, while in use, smoke started coming out of the set.

Upon disassembly, this is what I found:







Any ideas what could have caused this premature failure? I *think* the TV was still working when the set was smoking, but I'm not 100% sure.

(Look at attachments to see higher resolution versions)

[cheapie]

Re: Sanken PSA10982J M Exploded Primary Capacitor

Power surge? Fake cap? Rectifier problems?

[kc8adu]

Re: Sanken PSA10982J M Exploded Primary Capacitor

is the board dark under it or is that a shadow?
overvoltage like a high neutral?

[mockingbird]

Re: Sanken PSA10982J M Exploded Primary Capacitor

Nope no power surge AFAIK, and that's just a shadow...

[mockingbird]

Re: Sanken PSA10982J M Exploded Primary Capacitor

Ok, I got a confirmation that the set was working while the smoke was coming out of the capacitor... I'll probably replace the bridge rectifier anyways with a better brand just to be safe eventhough it does not measure short as far as I can tell. Anyone have any theories?

[goontron]

Re: Sanken PSA10982J M Exploded Primary Capacitor

Ok, I got a confirmation that the set was working while the smoke was coming out of the capacitor... I'll probably replace the bridge rectifier anyways with a better brand just to be safe eventhough it does not measure short as far as I can tell. Anyone have any theories?

internal short in the cap or a failing diode in the bridge?
I've had diodes test good on the LV that a DMM uses but goes short on mains voltage.

[ben7]

Re: Sanken PSA10982J M Exploded Primary Capacitor

Maybe just age and heat?

Could also be a random failure, which does happen once in a while.