Re: Inside A Plasma Cutter (Must See Pictures for SSTCers!)

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Original poster: "Jim Mitchell" <Electrontube-at-sbcglobal-dot-net> 

Hello John,

That might explain their rating of 1200v,  I didn't look to see if they were
in series,  but 1200X6 would give 7200v of rectfication,  so perhaps the
transformer gives 5kv? out.

Something I've noticed,  that even IF the ground clamp isn't connected to
the work,  I can still gouge the metal with the torch.  This also lead me to
believe that the output is high frequency as well, because we all know that
a unrectified flyback will arc to ungrounded metal,  but a rectified flyback
will not (or just make small blue sparks to the metal)

I guess I can still gouge the metal without being grounded, because the arc
is being started in the torch head, and then blown out by the air stream.

It seems plasma cutters are kind of a "mystery device" ;-)

Regards - Jim Mitchell
----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Thursday, June 10, 2004 6:52 PM
Subject: Re: Inside A Plasma Cutter (Must See Pictures for SSTCers!)


 > Original poster: John Keith <jskeith-at-interaccess-dot-com>
 >
 >
snip.
 >
 > Hi Jim,
 > Yes, the diodes are for rectification. Plasma cutters are DC machines, the
 > high frequency is super-imposed on the DC to start the arc, just like a
TIG
 > welder.
 >
 > Regards,
 > John Keith