... (ARC-250) Machine 1 manual welder 2 pulse width technique 3 electrode:Acidic, Alkaline, cellulos Inverter DC Manual Welder (ARC-250) ... size and light in weight.2 Adopting pulse width technique. 3 Protection equipment is set internally to prevent over heat, ... , carbon steel, pure copper(red copper)and so on7 Usable electrode: Acidic, Alkaline, cellulose8 Adopting passive power factor correction, and ...