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Slothie · 5th Sep 2020, 9:36 pm

Its probable the electrolytic will need re-forming at very least if its not been used in years.
Connect an incandescent bulb (e.g.12w 12v bulb from car) in series with the cap and connect to a suitable power source (could even be the transformer/rectifier you already have). If the capacitor is still passing a significant current after a few minutes then its probable the electrolytic is toast. Leave the capacitor connected for several hours to allow the oxide film to re-form before removing the bulb. Its probably worth checking the current with a meter too - with no load there should only be a small leakage through the capacitor. With the transformer switched off and no load the voltage across the capacitor should fall fairly slowly.

5th Sep 2020, 9:36 pm	#21
Slothie Octode Join Date: Apr 2018 Location: Newbury, Berkshire, UK. Posts: 1,287	Re: I found it !. A very sorry looking MK14 Its probable the electrolytic will need re-forming at very least if its not been used in years. Connect an incandescent bulb (e.g.12w 12v bulb from car) in series with the cap and connect to a suitable power source (could even be the transformer/rectifier you already have). If the capacitor is still passing a significant current after a few minutes then its probable the electrolytic is toast. Leave the capacitor connected for several hours to allow the oxide film to re-form before removing the bulb. Its probably worth checking the current with a meter too - with no load there should only be a small leakage through the capacitor. With the transformer switched off and no load the voltage across the capacitor should fall fairly slowly.