On 06/21/11 12:59 AM, Alan Melia wrote:
David Another important factor when considering power supply caps is ripple current rating. It is generally the ripple current that makes them get warm.
Yes. I must admit I did not give that any thought, which was rather stupid of me. But I did not buy cheap caps. I will check the ripple ratings, but its hard to know exactly what is needed.
I think the "usual" thumbnail calculation still work for caps if you can reduce the temperature by 20 degrees they will last at least 4 times as long. That is an activation energy (Arrhenius eqn) of about 1ev. I also believe though I cant quote that they are best run at about 75% of their specified working voltage. I have always wonderd about this but it would seem to be a mistake to have too low a voltage on electrolytics ...maybe something to do with the strength of the instulating layer formed.
Yes, I have heard this before about not using them at too low a voltage. I don't know whether its an old-wives tale, or if there is any truth to it.
Alan G3NYK
Thanks for your comments Alan, Dave G8WRB. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
