At 05:52 PM 10/19/2000 -0700, you wrote:
>
>I would like to reform the PS caps in an old Swan Amp that has not
>been turned on for over 10 years. I have a few questions before I
>start. I will be using an old Eico Cap tester but the eye tube no
>longer works. The output voltage is still there and is variable
>from 0 to about 400 volts. I will use external meters to monitor
>voltage and current.
>
>Questions:
>
>1. When starting at 0 volts and going up what should the current be
> limited to???
>
The Mallory manual I have says no higher than 10 ma during re-forming but
when I've done this I've usually limited it to 2 or 3 ma. Turn up the
voltage until the current hits 2 or 3 ma. Wait for it to fall to 500 micro
amps or less. Repeat until you get up to full rated cap voltage ( or the
400 volt max for your tester).
>2. When the voltage reaches the rating of the Cap what should the
> leakage current be??? (Ball Park)
>
Depends on the cap value + it's voltage rating + the manufacturer. The
different manufacturers use different formulas for calculating the normal
leakage current. If you tell me what these are I'll see if I have the
data. My experience has been that regardless of manufacturer, these big
electrolytics will generally have a leakage current or 400 micro amps if
they're good, and after they're reformed. Sometimes the leakage falls to
under 100 micro amps if you let them sit long enough at full voltage.
>Thanks guys
>
>Art
>KB7WW
>
>--
>FAQ on WWW: http://www.contesting.com/FAQ/amps
>Submissions: amps@contesting.com
>Administrative requests: amps-REQUEST@contesting.com
>Problems: owner-amps@contesting.com
>
>
>
--
FAQ on WWW: http://www.contesting.com/FAQ/amps
Submissions: amps@contesting.com
Administrative requests: amps-REQUEST@contesting.com
Problems: owner-amps@contesting.com
|