High stability of weld. Save more than 30% power supply, lower the costs. Three-phase balance input, power factor is up to 95%. The lower weld current and electrode force. No loss of inductance in secondary circuits. Electrode longevity more than doubled and reduce the grinding time of electrode. Reduce greatly the costs in electric installation and water, gas auxiliary equipment. Control and analyze welding parameters accurately, fast and comprehensively. Shorten the time of weld and improve the working efficiency and quality. Wide application, especially for mild steel, stainless steel, copper, aluminum, galvanized sheet.