An arc welding power source that maintains current at a relatively constant level, regardless of fairly large changes in voltage caused by changes in arc length. This type of power sources is used with manual processes like Shielded Metal Arc Welding (SMAW) and Gas Tungsten Metal Arc Welding (GTAW), Plasma Arc Welding (PAW), as well as with some Submerged Arc Welding (SAW) applications. Constant current power sources are sometimes called droopers because the volt-ampere curve that demonstrates the relationship between output voltage and output current is steep. See also Welding Power Source and Constant Voltage Power Source.
