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Miller Electric Mfg. LLC. - Big Blue® 800 Duo Air Pak Welding

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.

Features & Benefits

Multi-arc Welding

One dependable engine—two independent arcs with up to 400 amps each. Or plug in additional inverters for a true multioperator work platform! Example: Two additional XMTs equals four operators, up to 200 amps each.

Electronic Engine Display

Simultaneously displays fuel level, engine hours, coolant temperature, oil pressure, battery volts, and engine RPM. 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 greater fuel savings and longer compressor service intervals.

Low OCV Stick (VRD)

Reduces the open-circuit voltage to 15 volts when the welding power source is not in use, increasing operator safety without compromising arc starts. Remote Oil Drain Prevents spills and makes servicing engine and compressor oil easy.

More Power & Increased Efficiency

33 percent increase in rated output equals 800 amps of weld power and 27,000 watts of generator power. More arcs and better fuel economy equal increased profits for your business.

Heavy-Duty Low-Speed T4F and T4i Industrial Diesel Engines

The cleanest, greenest diesel power available. Utilizes Diesel Oxidation Catalyst (DOC) technology to keep the air clean with NO exhaust after-treatment maintenance.

The Vault

The vault allows for the ultimate control board reliability in CC/CV models. Hardened solid-state control technology, housed in a sealed vault.

Infinite Arc Control

Allows the arc characteristics to be changed for specific applications in Stick, MIG and FCAW Thermal Overload Protection Prevents machine damage if the duty cycle is exceeded or airflow is blocked.


Key Specifications
Weldable Metals Stainless Steel, Steel
Horsepower 65.7 hp
Rated Output 1 Welder: 800 A at 38 V, 100% Duty Cycle / 2 Welders: 400 A at 36 V, 100% Duty Cycle
Net Weight 2095 lbs
Engine Brand/Compliance Deutz T4F

Company Info

1635 W. Spencer St.
Appleton, WI
US, 54912-1079


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