Patent ID: 6313429
Filing Date: 2001-11-06
Classification: F23G,H05H

Abstract:
A method of operating a plasma arc system that treats a workpiece, the method comprising:providing a plasma arc device that includes an electrode, a plasma gas ring and a nozzle;providing at least one power supply having a first terminal connected to the electrode, a second terminal connected to the nozzle and a third terminal connected to ground and to the workpiece;supplying gas to the plasma gas ring;applying a first electrical potential to the electrode and applying a second electrical potential different from the first potential to the nozzle such that a potential difference is created therebetween;initiating a first arc between the electrode and the nozzle to form a plasma gas;heating the workpiece with the plasma gas to thereby raise the temperature of the workpiece to a conducting temperature; andautomatically initiating a second arc between the electrode and the workpiece whenever the temperature of the workpiece reaches the conducting temperature such that a ground point is found by the second arc without extinguishing the first arc.