Miller Millermatic 355 Pulsed MIG Welder, 20-400A, 208/240/460/575V, 907808
The Miller Millermatic 355 is a pulsed MIG welder for MIG, flux-cored and pulsed MIG welding in manufacturing, construction and fabrication. It connects to North American single- or three-phase power at 208, 240, 460 or 575 V, is rated 310 A at 29.5 V with a 60% duty cycle, and welds aluminum, stainless and mild steel up to 1/2 in. thick.
Output covers 20-400 A with 90 VDC maximum open-circuit voltage and 50-800 IPM (1.3-20 m/min) wire feed speed, and the input voltage selection switch sits in the wire drive compartment, with an error shown if the wrong input is selected. The 7-inch color LCD brings Auto-Set Elite, an electronic parameter chart and program mode, and Trigger Program Select changes programs with a tap of the gun trigger. Locks and Limits keep parameters within the welding procedure specification (WPS), and a USB port updates software and transfers programs.
This base power source comes with a 9 ft (2.7 m) industrial power cord, a 300-amp, 15 ft (4.5 m) Bernard BTB MIG gun fitted with AccuLock S consumables, a work cable and clamp with a 50 mm Dinse-style connector, a flow gauge regulator and gas hose, reversible drive rolls, extra contact tips and a material thickness gauge. It feeds solid steel, stainless, flux-cored, metal-core, aluminum and silicon bronze wire from 12 in. spools, EZ-Latch running gear is optional, and the welder reaches full output on generators of 19,000 watts or more.
Highlights
Base power source; EZ-Latch running gear is optional
Rated 310 A at 29.5 V, 60% duty cycle; 20-400 A amperage range
Manual input voltage switch for 208, 240, 460 or 575 V, single- or three-phase
MIG, pulsed MIG (GMAW-P) and flux-cored; aluminum, stainless and mild steel up to 1/2 in. thick
7-inch color LCD with Auto-Set, electronic parameter chart and Trigger Program Select
USB port for software updates, settings backups and program transfers
Specifications
Brand | Miller |
Manufacturer part number | 907808 |
Processes | MIG (GMAW), pulsed MIG (GMAW-P), flux-cored |
Input voltage | 208, 240, 460, 575 V; 1- and 3-phase |
Rated output | 310 A at 29.5 V, 60% duty cycle |
Amperage range | 20-400 A |
Max open-circuit voltage | 90 VDC |
Wire feed speed | 50-800 IPM (1.3-20 m/min) |
Wire diameter | Aluminum .035-.047 in.; metal-core .045-.052 in.; stainless .023-.045 in.; solid steel and flux-cored .035-.045 in.; silicon bronze .030-.035 in. |
Spool size | 12 in. (305 mm) |
Material thickness | Mild steel 22 ga. (0.6 mm) to 1/2 in. (12.7 mm); aluminum 18 ga. (1.2 mm) to 1/2 in. (12.7 mm) |
Weldable metals | Steel, stainless steel, aluminum, specialty metals |
Generator | Full output at 19,000 W (19K) or higher |
Weight | 99 lbs |
Dimensions | 26.25 x 13.75 x 19.25 in. (L x W x H) |
Portability | Running gear / cart (optional) |
What's in the box
Millermatic 355 power source with 9 ft (2.7 m) industrial power cord
15 ft (4.5 m) 300-amp Bernard BTB MIG gun with Bernard AccuLock S consumables for .035/.045 in. (0.9/1.2 mm) wire
10 ft (3 m) work cable with clamp and 50 mm Dinse-style connector
Flow gauge regulator and gas hose for argon or AR/CO2 mix
.035/.045 in. (0.9/1.2 mm) reversible drive rolls
Extra .035 and .045 in. (0.9 and 1.2 mm) contact tips
Material thickness gauge
Good to know
Check the input power (voltage, phase and amperage) against your supply before you order.

