[sdiy] storing alu electrolytics

[ASSI]

On Friday 12 March 2004 13:48, Czech Martin wrote:
> Has anybody any information on how long the isolation
> oxide will be sufficient if a alu lytic cap is stored?
> I plan to build a PSU that will be used only once a year.
>
> Is there a problem when firing up so seldom?

Maybe, in any case you should provide for some extra margin for the 
voltage rating of the cap and take into account that it's capacity will 
change over time.

> Other way round: should vintage gear be fired up every
> so and so many month to strengthen the isolation
> oxide?

Don't know about every month, but from experience with old tube radios 
I think it should be avoided to change the usage pattern very abruptly. 
Also if equipment has been stored under uncontrolled conditions for a 
long time, let it sit in the new (and stable) environment for a few 
days before trying to revive it. It helps to limit inrush current and 
perhaps provide a somewhat lower voltage (especially if you have gear 
old enough to be designed for 220V max. mains instead of the 230V that 
are now in use).

Also, when you power old gear on, let the equipment run for several 
hours at a time, otherwise the extra stress from power and heat cycling 
is probably more detrimental than any helpful effects from re-forming 
electrolytic caps.


Achim.
-- 
+<[Q+ * Matrix-12 * WAVE#46 * microQkb/Omega * XTk/30 * sonic heaven]>+

Factory and User Sound Singles for Waldorf Q, microQ and rackAttack:
http://homepages.compuserve.de/Stromeko#WaldorfSounds