Big Blue® 400 Pro Diesel

Big Blue® 400 Pro Diesel


Designed with the professional in mind, the Big Blue 400 Pro is the best for ease of use, reliability and fuel economy.


Heavy-Duty Low-Speed Kubota V1505 Industrial Diesel Engine

Used in industrial applications around the world, the V1505 is designed to run 10,000 hours before major overhaul. Backed by worldwide support and service.

Auto Remote Sense™ (ARS)

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


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.

Simple-to-Set Controls

Requires no elaborate procedure - just select process and weld!

Quiet Operation

Improves work site safety and communication.

HD Powder Coat

All painted sheet metal is pretreated with a zinc-rich primer to provide extra protection against rust & corrosion (comparable to stainless steel).

Digital Meters with SunVision™

Enables welding parameters to be viewed with greater clarity at virtually any angle. Meters can be seen clearly even in direct sunlight.

Advanced Features for the Professional Welder
  • Adaptive Hot Start™ makes starting stick electrodes easy without creating an inclusion.
  • Infinite arc control available in the Stick and Wire modes for easier fine tuning of tough-to-weld materials and out-of-position applications.
  • Lift-Arc™ TIG provides arc starting that minimizes the risk of electrode/work contamination without the need for high frequency.



Industrial USB Port

Quickly upload the latest software and download machine log files to retrieve in-depth information such as diagnostics and machine statistics.

Low OCV Stick (VRD)

When activated, reduces the open-circuit voltage to 15 volts when the power source is not in use, increasing operator safety without compromising arc starts.

Other Standard Features

Output contactor control, automatic idle, thermal overload protection, and 120-volt engine block heater.


General Specifications

TitleBig Blue® 400 Pro (Kubota)
Industries InterestsConstruction
Maintenance and Repair - Field Operations
Mechanical Contracting
Pipe Fabrication / Construction
Cold Weather Starting AidsEngine Block Heater
Glow Plugs
Engine BrandKubota
Engine ComplianceT4F
Engine Idle Speed1500 RPM
Engine Weld Speed1800 RPM
Fuel Tank Size11.5 gal.
Fuel TypeDiesel
Horsepower20.2 hp
Weldable MetalsStainless Steel
Rated Output400 A at 24 V, 100% Duty Cycle
350 A at 27 V, 100% Duty Cycle
300 A at 32 V, 100% Duty Cycle
Single Phase Generator
Continuous Power
10000 W
Single Phase Generator
Peak Power
12000 W
Sound RatingIdle: 66 dB / Weld: 71.6 dB
Rated Carbon Diameter3/16 in (4.8 mm)
Current TypeDC
Max Open Circuit Voltage85 VDC
Amperage RangeAmperage Min Max 20 - 400
PortabilityLift Eye (Standard)
Trailer (Optional)
Weld OutputCC
Net Width26.25 in
Net Height32 in
Net Length56 in
Net Weight950 lbs