An arc welding power source with a volt-ampere relationship yielding a small welding current change from a large arc voltage change. See WELDING POWER SOURCE.
A constant current power source has a “drooping” output characteristic; the output voltage decreases as welding current increases. This type of power supply is used with shielded metal arc welding (SMAW), gas tungsten arc welding (GTAW), and submerged arc welding (SAW).