Constant current welding power supply with an upslope starting current

摘要

A constant current welding power supply having a single transformer with a primary winding connected to a three phase input source of line voltage and two secondary windings each having a bridge rectifier for providing an open circuit starting voltage separate from the arc working voltage. Each bridge rectifier is fired by separate firing means controlled by a logic control means. One bridge rectifier is energized with an advancing firing angle proportional to a ramp output signal enabled through the control means in response to a predetermined drop in output voltage. The other bridge rectifier is energized in synchronism with the line voltage for a predetermined period of time following the predetermined drop in output voltage.