Miller 320A/BP Welder

The Miller 320A/BP is a legendary, heavy-duty, industrial AC/DC TIG and stick welder. Built like a tank in the 1970s, it is primarily used for precision aluminum and stainless-steel fabrication. Known for its smooth arc and reliability, it uses traditional transformers and spark-gap high-frequency (HF) technology. Core Specifications Rated Output: 320 Amps Duty Cycle: 60% duty cycle at 200 Amps Primary Input Power: Usually requires heavy 208/230/460V 3-phase power, though some are wired for single-phase. Weight: ~850 lbs (massive transformer-based unit) Key Features AC/DC Capability: Features AC for aluminum/magnesium and DC for mild steel, stainless, and other alloys. Spark-Gap High Frequency: Uses mechanical spark-gap points for arc starting and stabilization in TIG mode. Mechanical Post-Flow Timer: Adjusts how long the shielding gas continues to flow after the arc stops, protecting the tungsten. Remote Foot Pedal: Compatible with remote pedals for amperage control during the weld.