... 2.4T control,ease of long-weld opera dc/ac inverter square wave spot welding TIG315AC/DC :welding style: DC TIG, ... , carbon steel, copper, titanium and other materials;advanced inverter technology:dual inverter control technology, the conversion efficiency of 85%, no-load ... machine is stable;excellent welding performance: 1. quality square wave power supply,current zero-crossing time is short,stable arc ...