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More cap dissipation stuff



Hi All,

	I did a fun thing!  I took some of the caps I tested last night and
drilled a hole through them so I could slip a small resistor into the
center of the caps and epoxy it inside.  This allows me to determine the
true thermal dissipation of the cap package and the dissipation factor of
the caps by running DC current through the resistors to get a known power
input (I guess I am getting good at this stuff ;-)).

The Panasonic 0.056uF 1600 volt caps that I love so much have a thermal
dissipation 19.8 degrees C per watt and a dissipation factor of 0.00157 at
350kHz.  Their rated numbers are 40 C/W and 0.0032.  "Extremely" close to
the "50% rule"...  I think I hear the Panasonic cap engineers thinking ;-))
 So they can take twice the current their published ratings suggest.

I tried one of Finn's Phillips 0.056uF 1600 volts caps and I get 15 degrees
C/watt and a dissipation factor of .0010 .  The larger package dissipates
more heat but they also seem to have only 64% of the internal resistance of
the Panasonics...

Cheers,

	Terry