When the cap gets too big...

[Bill Layer]

Hi,

Saw the thread about cap size and needed to throw in my two cents. Big 
isn't always more when dealing with cap size. As a cap passes it's maximum 
effective size, another issue comes up, that of xfmr saturation on the 
power cycle.

As I know it, there comes a point where the cap is so large (and so low in 
resistance compared to the Zsec of the xfmr) that the turn-on point for the 
rectifier causes such a heavy current inrush that the transformer core 
saturates trying to push against the brick wall (low as it may be :) that 
the too-large cap presents. I don't need to expound on the non-plus nature 
of core saturation, or the noise and other issues it introduces.

Anyone have experience with this?




+----------------------------------------------------------+
|      "The" Bill Layer - Frogtown, Minnesota. U.S.A.      |
| Vacuum tubes, Analog, Motorcycles and Other Alternatives |
+----------------------------------------------------------+	
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| <blayer at uswest.net> |  | <b.layer at vikingelectronics.com> |
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