Big Blue® 800 Duo Air Pak™


Big Blue® 800 Duo Air Pak™


The most powerful T4F diesel welder/generator/air compressor in the industry. The Big Blue 800 Duo Air Pak offers robust output for welding and power generation, and is ideal for dual-operator applications on labor intensive jobsites, or jobsites with limited space.


icon_t4f.pngHeavy-Duty Low-Speed DEUTZ TD2.9 L4 T4F Industrial Diesel Engine
The cleanest, greenest diesel power available. DEUTZ T4F models utilize diesel oxidation catalyst (DOC) technology to keep the air clean with NO exhaust after-treatment maintenance.

icon_arcr.pngArcReach® Technology
Exclusive ArcReach technology uses existing weld cables to communicate process adjustment commands back to the welder generator. With an ArcReach system, amperage & voltage are conveniently located at the operator's fingertips - not back at the power source.


Multi-Arc Welding
One dependable engine - two independent arcs with up to 400 amps each (or 800 amps for a single operator). Plug in additional inverter welders for a true multi-operator (3+ arc) work platform!


Increased Productivity & Safety
More arc-on time, and reduced exposure to slip, trip, and fall hazards can be realized using ArcReach because less time is spent going back to the welding power supply to set process and arc amperage or voltage.


icon_empty.pngIncreased 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.


Electronic Engine Display
Electronic engine display simultaneously displays fuel level, engine hours, coolant temperature, oil pressure, battery volts, air pressure and engine RPMs. Also tracks oil change intervals and displays engine diagnostics for quick and easy servicing.


Air Compressor - Ingersoll Rand
Ultra-reliable industrial rotary screw air compressor. 30,000-hour life expectancy. Independent on/off control for applications not requiring compressed air — allows for greater fuel savings and longer compressor service intervals.


Dynamic DIG™
Unlike conventional DIG that provides a preset amount of short-clearing current, Miller’s proprietary Dynamic DIG works on a time-based algorithm that automatically adjusts the amount of current required to clear a short. What does this mean? A smoother more consistent arc that can be tailored to match application, material, fit-up, and welder technique.


Other Standard Features
Output contactor control, automatic idle, thermal overload protection, digital meters with SunVision™ and 120-volt engine block heater.


General Specifications

TitleBig Blue® 800 Duo Air Pak™
Industries InterestsConstruction
Pipe Fabrication / Construction
Maintenance and Repair - Field Operations
Mechanical Contracting
Education / Training
Cold Weather Starting AidsEngine Block Heater
Glow Plugs
Engine BrandDeutz
Engine ComplianceT4F
Engine Idle Speed1350 RPM
Engine Weld Speed1800 RPM
Fuel Tank Size25 gal.
Fuel TypeDiesel
Horsepower65.7 hp
Weldable MetalsStainless Steel
Rated Output1 Welder: 800 A at 38 V, 100% Duty Cycle
2 Welders: 400 A at 36 V, 100% Duty Cycle
Single Phase Generator
Continuous Power
12000 W
Single Phase Generator
Peak Power
15000 W
Sound RatingIdle: 71.3 dB / Weld: 78.9 dB
Three Phase Generator
Continuous Power
20000 W
Three Phase Generator
Peak Power
27000 W
Rated Carbon Diameter1/2 in (12.7 mm)
Current TypeDC
Max Open Circuit Voltage85 VDC
Amperage RangeAmperage Min Max 20 - 800
PortabilityFork Pockets
Lift Eye (Standard)
Trailer (Optional)
Weld OutputCC / CV
Net Width28.5 in
Net Height46 in
Net Length69.5 in
Net Weight2095 lbs