2. After the gas flow stabilizes, the high frequency circuit is activated.
The high frequency breaks down between the electrode and nozzle
inside the torch in such a way that the gas must pass through this arc
before exiting the nozzle.
Energy transferred from the high frequency arc to the gas
causes the gas to become ionized,
therefore electrically conductive.
This electrically conductive gas creates a current path
between the electrode and the nozzle,
and a resulting plasma arc is formed.
The flow of the gas forces this arc through the nozzle orifice,
creating a pilot arc.