Miller Big Blue 800X Duo Air Pak

More power

33 percent increase in rated output equals 800 Amps of weld power and 27,000 Watts of generator power.

Multi-arc welding

  • One dependable engine — two independent arcs with up to 400 Amps each. Or plug in an additional inverter for a true multi operator work platform!
  • Example: One additional XMT equals 3 operators, up to 240 Amps each. Premium quality arcs allow operators to work independently with no arc interaction. Multi operator welding has never been easier or more versatile.

Increased efficiency

  • More arcs and better fuel economy equal increased profits for your business.
  • Estimated savings are 34 percent with a dual-operator unit versus two single-operator units.
  • Remote oil drain for engine and compressor prevents spills and makes servicing easy.
  • Electronic engine display simultaneously displays fuel level, engine hours, coolant temperature, oil pressure, battery Volts, engine RPM, air pressure, and compressor hours.
  • Tracks oil change intervals and displays engine diagnostics for quick and easy servicing.

Deutz 2011 L041 - Heavy-Duty Low Speed Industrial Diesel Engine

Designed, built and proven to operate over 10,000 hours before the first basic overhaul.

Ingersoll Rand

  • Ultra-reliable industrial rotary screw compressor.
  • 30,000-hour life expectancy.
  • Independent on/off control for applications not requiring compressed air — allows greater fuel savings and longer compressor service intervals.
  • 100PSI, 60CFM, 100% Duty Cycle.

VRD Standard (CAT.C AS1674.2)

  • Reduces the open-circuit Voltage to 15 Volts when the welding power source is not in use, increasing operator safety without compromising arc starts.
  • Infinite arc control allows the arc characteristics to be changed for specific applications in Stick, MIG and FCAW.

Auto Remote Sense™

(ARS) detects if a remote control is plugged into the 14-pin receptacle and eliminates confusion of a remote/panel switch.

Auxiliary Power*

  • 1 x 380 V 32 Amp Sockets.
  • 2 X 240 V 15 Amp Sockets.
  • RCD.

*Generator auxiliary power is 60Hz, and intended for operating equipment associated with welding, such as angle grinders, drills and floodlights. Some Australian 50Hz equipment incorporating induction motors, such as pumps, fans, air compressors, refrigeration or air-conditioners, may not operate correctly and could be damaged. Refer to appliance supplier or manufacturer to confirm suitability.

Technical Data

Welding Mode:  CC/CV/DC

Amp/Volt Range: 20 - 400 A

Rated Output: 400 A at 36V, 100% Duty cycle, 700A at 44V 100% Duty cycle, 400A at 34 V 100% Duty cycle

Generator Power: 3-PH Peak 27 000 Watts, Continuous: 20 000 Watts, 1-PH Peak 5 500 Watts, 4 000 Continuous

Dimensions (mm): H 1194  W: 724 D: 1765

Weight (without Fuel): 968.4 kg

Applications and Processes


Railroad Maintenance

Mining Maintenance

Maintenance & Repair


Submerged Arc



Flux Cored


Compressed Air

Air Plasma Cutting & Gouging

Air Carbon Arc