Arc welding current control - partic. establishing the arc in TIG or plasma welding

摘要

Regulation of the current in arc welding at the start-up of the arc, utilising in known manner (I) a main energy source for establishing the main arc between an electrode and a workpiece and (II) and actuating device for striking the arc, whereby the activating device can supply a test current between the electrode and workpiece, determined by means of a sensing element which is brought into operation at a pre-determining value of the test current corresp. to a pre-determined impedance across the main energy source, a control signal being transmitted from the sensing element to the main energy source which establishes the main arc and regulates the main current to the pre-determined value.