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LOSS FACTORS??
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From: Thomas McGahee [SMTP:tom_mcgahee-at-sigmais-dot-com]
Sent: Monday, February 02, 1998 10:17 AM
To: Tesla List
Cc: mwise-at-ns.sosis-dot-com
Subject: Re: LOSS FACTORS??
> From: Zuma [SMTP:mwise-at-ns.sosis-dot-com]
> Sent: Saturday, January 31, 1998 10:45 PM
> To: tesla-at-pupman-dot-com
> Subject: LOSS FACTORS??
>
> Could someone please tell me where the loss factors for di-electrics
> come from. How are these figures derived? Are they based density, what?
> I would like to know for the specific reason so I can make sense of all
> of this talk of high loss or low loss for different caps!
>
> Chris
>
Most capacitor factors are given as ratios compared to AIR. The loss factor
relates to how much of the applied AC is dissipated/wasted in the form of
heat. Note that this value is a function of frequency, and is thus
different at 60HZ and 100Khz, for example. USUALLY the higher the
frequency the greater the loss, but there are some exceptions.
Polar materials have greater dielectric loss than non-polar materials.
In a cap if you measure the applied RMS power and the returned RMS
power, the difference would be due to the LOSS.
Materials like mylar have dissipation losses that are many thousands of
times greater than materials like polyethelene.
Plate glass and plexiglass caps get VERY hot in TC operation. So hot
that the glass cracks and the plastic melts. Ask anyone who ever
built a cap using vinyl what the effects of high loss are, and they
will tell you a sad tale of liquified vinyl. Not a pretty sight.
Of all of the readily available materiels, the best are polyethelene,
polypropylene, and styrene. If you got lots of money to throw around,
or just a good source of free material, then we might add Teflon in
there. Teflon has little itty bitty holes in it, though, so you best
be careful.
Save yourself a LOT of trouble and get polyethelene or polypropylene
and get on with the building of your caps.
Hope this helps.
Fr. Tom McGahee