Arc 400i is an IGBT based inverter controlled power source designed for MMA welding. The power source is designed as a compact power source for easy portability. ï¼ -- Inverter controlled - efficient power usage. -- Light weight - for improved portability. -- Wide mains voltage tolerance - for stable welding controls. -- Protection against Over-Temperature, Under-Voltage, Over-Voltage and Single-phasing. -- User friendly controls Adjustable Arc force and Hot star