[Boatanchors] Capacitor Reforming

[J. Forster]

david freeman wrote:

> [snip] What rate of increase produces
> the best results? Does 50V/minute sound too fast? What is the maximum leakage
> current that would be acceptable for a “good” capacitor? Here is a common
> scenario, I’m at 50V and leakage current is 2mA, I increase to 100V and
> leakage goes to 10-12mA then gradually over the next minute drops back to
> 2mA. Am I watching the reforming process take place? Am I “pushing” the
> process too fast? All input welcome.

Yes.

As to reforming time, I let the cap tell me. It's important to keep the internal
dissipation low...  I usually stay below 100 milliwatts for things up to about C
battery size, 500 milliwatts for larger units.  I go up in about 25 V steps,
perhaps one step per hour, dissipation permitting.  It can take several days to
fully reform an old cap.

FWIW,
-John