A circuit for providing D.C. current from a power source having a current regulating input to a plasma system including an electrode and a nozzle with a plasma arc opening exposing the electrode to a juxtapositioned workpiece, which circuit has a first circuit branch for creating a pilot arc...http://www.google.es/patents/US5847354?utm_source=gb-gplus-sharePatente US5847354 - Arc transfer circuit
