There was a plague of failures a decade ago. But the same symptom is not only from bad manufacturing. I believe abuse, bad circuit designs also causes the problem. Newer equipment, in operation about a year, showing inflated capacitors that may got inflated suddently or may have been developing the inflation along some time.

What causes do you attribute for such to each; to sudden and to slow inflation ? When several failing/failed capacitors are in parallel, most show the dome or rupture or nothing visually, and there is usually no clues of heat rose in them. And very often seen in boards with inductor circuits nearby.

----> https://duckduckgo.com/?t=ffab&q=inflated+capacitors&iax=images&ia=images

 

Bad caps (mainly still from bad manufacturing) is a plague that still haunts us, it's just not as bad as before IMO. I've replaced the exact same junk brand cap voltage and capacity with quality caps from OEMS like Panasonic with never an additional capacitor failure.

 

Thanks.
If I want to bulge, leak, explode an electrolytic capacitor, what should I do to it other than if the voltage is not exceeded ?

 

Cause the Capacitor to create excessive HEAT and it will fail every time.
Capacitors generate HEAT because of a too-high ESR rating for the particular application.
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Thanks.
OK. 'cause the capacitor to create its own heat' - How is that done ? -That not being environmental heat or poor equipment dissipation-

 

At constant DC voltage, ESR has no effect because there is zero current.
With AC, ESR consumes power which is dissipated as heat.

 

All quality Electrolytics have 2 "Maximum-Current-Ratings",
usually the first one is at ~120hz,
and the second one may be at ~1000hz, or even somewhere around ~10,000hz.
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Here is a datasheet for a series of Nichicon electrolytic capacitors that have a claimed withstand of 3,000 hours (or 125 days) at maximum rated ripple current and temperature.

Nichicon are supposed to be quite a good brand; if you operate electrolytic capacitors close to their limits in terms of ripple current and/or temperature, don’t expect them to last 25 years.

https://docs.rs-online.com/13fd/0900766b813cd37a.pdf

 

A key factor is cap death is ripple. Poorly designed power supplies can destroy caps even if the voltages appear well within specs. Check the datasheet of the caps for ripple current maximum and measure the ripple in the current being fed to them.