[Boatanchors] Capacitor Reforming

[Bob Kulow]

<snip>
> Here is a common scenario, I=92m at 50V and leakage=20
> current is 2mA, I increase to 100V and leakage
goes to=20
> 10-12mA then gradually over the next minute drops
back to=20
> 2mA. Am I watching the reforming process take
place? Am I=20
> =93pushing=94 the process too fast? All input welcome.
>=20
> Dave, WW8S

I have a Sprague TO-6 and the manual is quite
helpful on=20
this topic.  I think BAMA has it for download.  Well
worth=20
the download time.

Anyway, according to the manual, when reforming a
'lytic,=20
keep the current down below 10 mA to prevent
overheating.
The table of acceptable leakage shows that a /new/
80 mF,=20
450 WVDC 'lytic should have a maximum leakage
current of=20
3.5 mA.  Leakage goes up with age.  To quote,
"Capacitors=20
with a leakage current of more than 15 mA should
almost=20
always be discarded."

Depending on how old the 'lytic is, it could take an
hour=20
or more to fully reform.  Be patient!

73
Bob WA2UEH

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=20