On Wed, 07 Oct 2009 22:27:31 -0500, Lostgallifreyan
wrote:

DaveC wrote in
al-september.org:

What was the existing cap?

DaveC wrote in
:
It's a Mallory FP119A.

Any clear indications as to why or how it failed?

No. Guesses: Old age? Heat?



Old age isn't a mechanism. Heat could well be right. Also accelerated loss
of electrolyte. Did the cap look like it had burst from inside earlier than
any final appearance of internal gubbins? Another possibility is the voltage
it saw. When you say 110 volts, you mean the mains, right? If so it will be
rectified and that cap will be seeing the peak value, not the RMS, so around
125V when under no load, so you really do need it to have a higher voltage
rating than that.

---

peak = RMS * sqrt(2) = 110 * 1.414 ~ 155V

JF