Miller Big Blue 400 Pro (Mitsubishi) Diesel Welder 907733 2025 New

Miller® Big Blue® 400 Pro 907733

The Miller® Big Blue® 400 Pro with Mitsubishi S4L2 engine is a low speed, EPA compliant compact diesel welder that is ideal for construction, piping and fleet use. It packs up to 400 amps of welding output at 100% duty cycle and provides 12,000 peak watts of auxiliary power. It is capable of carbon arc gouging using up to 1/4″ diameter carbons. When paired with the appropriate wire feeder, it can perform MIG, and flux-cored welding operations.

The Big Blue 400 Pro industrial diesel engine driven welder outperforms competitive machines and comes with the best service and parts support where it matters most, in the harshest real world conditions.

Processes

MIG (GMAW)

DC TIG (DC GTAW)

Stick (SMAW)

Flux Cored (FCAW)

Air Plasma Cutting and Gouging (PAC) with Optional Spectrum Models

Air Carbon Arc Cutting and Gouging (CAC-A) – capable 1/4″ carbons, rated 3/16″ carbons

Applications
Mechanical Contractors
Structural Steelwork
Fabrication
Maintenance
Repair
Rental
Construction

Features:

Superior Arc Performance
Four preset DIG settings (Stick)
Hot Start™ (Stick)
Lift-Arc™ TIG with Auto-Stop™ and Crater-out
MIG/FCAW arc performance

Ultra-adaptive arc control – Unlike conventional DIG that provides a preset amount of short-clearing current, Miller-exclusive Dynamic DIG technology works on a time-based algorithm that automatically adjusts the amount of current required to clear a short. Delivers 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!

Thermal Overload Protection Prevents machine damage if the duty cycle is exceeded or airflow is blocked.

Mitsubishi SL4L2 four-cylinder diesel engine. Designed to operate over 10,000 hours before the first basic overhaul. Backed by worldwide support and service.

Quiet at only 72.1 dba (97 Lwa) at 23 ft at maximum output. Improves work site communication.

The Vault-ultimate control board reliability. Hardened solid-state control technology, housed in a sealed vault. The vault’s sealed connections are made through watertight plugs that make these components impenetrable to dust and moisture.

Meter Maintenance Displays
Fuel gauge
Hour meter function
Oil change interval
High coolant temperature and low oil pressure shutdowns
Low fuel shutdown – engine shuts down before system runs out of fuel, making restarts easy.

Auto Remote Sense™ (ARS) Detects if a remote control is plugged into the 14-pin receptacle and eliminates confusion of a remote/panel switch.

Other Standard Features
Digital preset weld meters
Output contactor control
Automatic idle
120 V block heater

Specs

PLUS get a FREE 500 ft. reel of 2/0 neoprene jacketed welding cable with the purchase of this Miller® Big Blue® 400 welder. While supplies last. (No substitutions allowed.)

Kalas ToughFlex™ 2/0 welding cable, in 500 foot reel, is premium, neoprene jacketed, 600 volt copper cable designed to stay flexible, even in cold weather. Cable is marked in one foot increments for the entire length of the reel.

Resists oil, chemicals, water, ozone and solvents

EPDM insulation for optimum cold weather flexibility and excellent spatter resistance

Sequential foot-marked

RoHS compliant

UL® Listed