Electrolytic Capacitor Ratings [was Re: Choosing Parts?] Date: Thu, 22 Apr 1999 13:21:14 -0700     From: Chuck McManis      Kind of. Electrolytics are indeed made by plates in a conductive solution,     however when the voltage increases, it pulls the plates together (standard     columbs law stuff). When you exceed the rated voltage the force on the     plates is enough to pull the plate _through_ the dielectric and to make     contact. Surely you jest.  Do the math and compute the forces.  Also, explain how an entire plate moves through an entire layer of insulator---where is the insulator -going-? My understanding of how most caps failed was because an -arc- formed through part of the dielectric.  In essence, a spark punches a hole through it at some point where one of the plates just happens to have a microscopic peak and hence a locally-higher charge density.  The arc then (a) continues to short out the cap, and (b) generates a lot of heat.