Trying to create an HV arc

Rickam, Sun Sept 17 2023, 10:44PM

Hi all; infrequent poster;
I'm trying to generate an arc to initialize the current flow in a DIY plasma cutter: Link2
I'm using a 10kv furnace ignition transformer rather than the auto coil the creator used. I thought I'd simply wire the secondary to the torch head and lead wire and get an arc but failed.
When I disconnected one of the hv leads from the transformer I got arcing at the torch head which I didn't expect. Don't understand how the circuit is completed. I thought that might work but when I touched the lead wire to the work as is done on some commercial plasma cutters the arc stopped. I'm at a loss and hoping someone here has any suggestions. Thank you.


Rick A
Re: Trying to create an HV arc
orac12, Tue Sept 19 2023, 01:06AM

Can you post a drawing of what you have? And what kind of torch head are you using? Plasma cutters use a variety of ways of creating the pilot or starting arc.
Re: Trying to create an HV arc
Rickam, Tue Sept 19 2023, 02:55AM




Orac 12: Thank you for your reply; I thought I'd included a link to the wiring diagram of the plasma cutter but now I see that I hadn't and I can't yet figure out how to. If you'll go to this link you'll find the explanation and diagrams of what I'm trying to build: Link2 I'm trying to replace the auto coil circuit with a furnace transformer.

I'm using a Sure lok SL60 torch and to test the hv circuit I used a separate 120v power source for the transformer and connected one lead from it to the high power input to the torch and the other to the ground clamp. I had continuity on both but no arc. I then disconnected the lead to the ground clamp and got a 1/2" long arc from torch to ground! I don't know how the hv circuit gets completed.

Rick A