CONSTRICTION DETECTION CONTROL METHOD OF WELDING POWER SOURCE

摘要

PROBLEM TO BE SOLVED: To prevent a malfunction of constriction detection control, when simultaneously using a plurality of welding power sources.SOLUTION: A constriction detection control method of the welding power source regenerates an arc by reducing a welding current Iw1 when detecting this constriction, by detecting constriction Nd of a droplet being a precursory phenomenon of regenerating the arc from a short-circuit state by using a welding voltage detection signal Vd1 by at least two sets in the welding power sourced, by welding by respectively generating the arc in a common work by a plurality of welding power sources, and the welding voltage detection signal Vd1 includes a voltage value generated by an inductance value of a common current-carrying passage for carrying an added-up welding current Ig, and construction detection Nd is prohibited when discriminating (St) that a resistance value of the droplet reduces in the short-circuit state. Thus, erroneous detection of the constriction can be prevented without mutually notifying the sudden reduction timing of the welding current between the welding power sources.