Arc welding current supply - needs smaller filter capacitor by passing more current from second secondary winding through triac branch

摘要

An arc welding current supply for steplessly adjustable a.c. welding includes a transformer with two secondary windings. The first of the latter is connected through a triac, and the second through a d.c. filter capacitor, to one of the electrodes. Both windings are linked at their other ends to the workpiece or a counter electrode, perhaps via a choke coil. The current in the second secondary winding is designed to be only a fraction of the maximum in the first. The filter capacitor need only be dimensioned for a fraction of the maximum current, i.e. it will be cheaper and lighter. Flickering of the arc because of too large a capacitance is eliminated.