Hello All, I have on the bench a couple of PSU's which have some failed Nichicon PL series caps. They didn't "puke" their guts through the top, but instead "diarrhea'ed" corrosive brown electrolyte through the bottom, down the legs and onto the board. On one cap, the electrolyte rotted the cap right off the board leaving 2 little stubs, and also corroded a trace on the foil side.
The PSU's are Power-One MAP series and are ringing-choke topology. The semiconductors have date codes in 1993. The PSU's were used in a commercial application, fan-cooled. They had failed due to a different cause (startup resistors), were taken out of service, then stored for 5 or 10 years. I am now rehabilitating them for use as spares.
Between the 2 units there are 8 diarreah'ed caps, are all Nichicon PL series, all are 47 uF @ 35V. There are other-sized Nichicon PL caps on the boards and which have not leaked. Nichicon retired their PL series and now recommend the PM series as replacement. When rehabilitated, the PSU's will be shelf queens; how well do the newer Nichicon PM's suffer long term idleness? (Or have they not been around long enough for anyone to know).
The PSU's are Power-One MAP series and are ringing-choke topology. The semiconductors have date codes in 1993. The PSU's were used in a commercial application, fan-cooled. They had failed due to a different cause (startup resistors), were taken out of service, then stored for 5 or 10 years. I am now rehabilitating them for use as spares.
Between the 2 units there are 8 diarreah'ed caps, are all Nichicon PL series, all are 47 uF @ 35V. There are other-sized Nichicon PL caps on the boards and which have not leaked. Nichicon retired their PL series and now recommend the PM series as replacement. When rehabilitated, the PSU's will be shelf queens; how well do the newer Nichicon PM's suffer long term idleness? (Or have they not been around long enough for anyone to know).
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