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When the delivery man dropped my capacitors off earlier yesterday he did not ring the doorbell and I had no idea they had arrived on my front step. Then an intense rainstorm showed up and soaked the whole lot of my eight 1500uF, 450V caps. They have a tight plastic coating, and did not seem to consume hardly any water as they dried quick.

Are they okay to use?? How would you recommend to safely test one at a time to see how well they're working?

Maybe it would be best to do a typical charge-up with a rectified variac power source, voltmeter, and discharge into a bleed resistor and ground. I really don't need any extra possible dangers with the high current power supply I'm building, and want to be careful.

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Jeremy Adams
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    Wait, the delivery person left your package on your doorstep unattended? That sounds like it should be worth at least a complaint to the delivery company... – marcelm Jul 25 '16 at 07:54
  • I would ask the manufacturer: http://www.cde.com/product-support – jmr Jul 25 '16 at 03:26

1 Answers1

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Electrolytic Capacitors are sealed to keep the (liquid) electrolyte in, which inherently makes them sealed to keep liquids out. They are also designed to withstand cleaning with water or other solvents (think domestic dishwasher conditions).

However there is a concern with the shrink-wrapped insulation trapping water and your parts have a rather high voltage rating so you want to make sure the surface of the rubber insulator is dry. Here (from CDE's application guide) is the recommended procedure following aqueous cleaning if you want to be 105% safe:

Aqueous Cleaning Water with a mild detergent may be used to clean aluminum electrolytic capacitors. However, immediately dry the capacitors in hot air at about 85 ºC for 5 or more minutes but not hotter than the capacitors’ maximum storage temperature. Water can become trapped beneath the sleeve which may not be dispelled by evaporation at room temperature. Water can be trapped under the sleeve and cause hydration and discoloration of the aluminum cases; although this does not affect capacitor operation.

Spehro Pefhany
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