Re: Potato Chips (fwd)

---------- Forwarded message ----------
Date: Mon, 27 Apr 1998 09:43:27 -0700
From: Jim Lux <jimlux-at-earthlink-dot-net>
To: Tesla List <tesla-at-pupman-dot-com>
Subject: Re: Potato Chips (fwd)

> Gary - do *not* remove the varnish off the laminations!  The varnish is
there to 
> electrically isolate each metal plate from the next.  As I recall, the
> reduces either hysteresis losses or eddy current losses in the
> Bert Pool
> bertpool-at-ticnet-dot-com

Yep.. The reason to use laminations (as opposed to a solid bar of steel or
iron) is to reduce the eddy current losses. If the laminations aren't
insulated, they would act as a solid bar. The trick is to keep the
insulation thin, to reduce the overall size of the transformer, which
reduces the length of copper for a given number of turns, which reduces the
resistive losses. 

I might add that powdered iron and ferrites  are electrical insulators, so
they don't need laminations. However, if you ever took apart a tape wound
toroid, you'd find insulation between the windings.