Re: What it all does..

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Terry Fritz" <twftesla-at-qwest-dot-net>

Hi Pjj,

Of course, most small coils do run off 120VAC :-)  However, I assume you
mean why one can't run the primary coil from say 100 volts instead of many
thousands of volts.

Tube and other CW coils do run with only a few hundred volts on the
primary.  However, all big disruptive type coils tend to use very high
firing voltages at around 20kV.  The high voltage is needed to force a lot
of current through the inductance of the primary coil.  Inductance acts
much like resistance in that it limits the current flow.  A 100uH primary
running at 200kHz has an impedance (like resistance for our purpose here)
of 125 ohms.  In order to get say 200 amps through that you need 125 x 200
= 25000 volts.  So we need lots of voltage to push lots of current through
the primary coil.

Higher voltages also help the spark gap to work.  However, solid state
elctronics has sort of removed that as a problem.

Cheers,
	
	Terry


At 11:38 AM 12/22/2001 -0800, you wrote:
>Why can't a TC run on 110v?
>
>