Kemppi FastMig KM 400 is an inverter MIG/MAG power source with a separate wire feeder and an interconnection cable from 15 to 20 m long. The maker gives 400 A at an 80% duty cycle and 380 A at a 100% duty cycle, supply 3 x 400 V. You work the Basic panel with knobs, also in thick gloves.
What this machine is for
This is a set for shipyards, steel structure plants and firms building pipelines and large tanks. A duty cycle of 380 A at 100% means welding thick plate through the whole shift without pauses for cooling, and 400 A at an 80% duty cycle is a working value, not a momentary peak.
The main feature of this configuration is reach. An interconnection cable from 15 to 20 m long lets you leave the source in one place and carry the feeder alone, for example inside a hull or onto a structure. Less moving of the machine means fewer breaks in work on large parts: bridges, ships and tanks.
The Basic panel has neither pulse nor a deep menu, so the setting comes down to the voltage and the wire feed. On thick steel that is an advantage, because the machine is simple to work and quick to change over. You weld aluminium with it in manual mode, but without pulse, so for thin parts in light alloys it is better to take a source with pulse.
The set is balanced electrically also with the cables fully rolled out, so the arc behaves the same close to the source and at the end of the run. The inverter modules have a higher energy efficiency than a classic transformer of similar power, and at the same time the machine keeps its resistance to hall conditions: metal dust, moisture and low temperatures.
Features and equipment
- Interconnection cable from 15 to 20 m: you weld within a radius of up to 20 m from the source, without moving the machine.
- Separate 4 roll feeder with a high torque: it pushes the wire through a long liner at a steady speed.
- Basic panel: two main knobs, work in gloves, a short time to get ready for work.
- Inverter power stage: good arc dynamics, less spatter and deep penetration on large sections.
- Stiff housing resistant to knocks: a build for metal dust, moisture and low temperatures.
- Cooling led to the torch: work at 400 A without overheating the handle.
- Interconnection cable in a reinforced version: it protects the cores from mechanical damage and limits voltage drops over a long run.
- A steady feed speed despite the long liner: the high torque drive does not lose the feed with the cable fully rolled out.
Cooling led to the torch lets you work at full current without pauses to cool the handle, and at 400 A it is the torch that tends to be the first part to give up.
Technical data
| Brand | Kemppi |
|---|---|
| Model | FastMig KM 400 |
| Supply | 3 x 400 V |
| Welding current at an 80% duty cycle | 400 A |
| Welding current at a 100% duty cycle | 380 A |
| Wire feeder | separate, 4 roll |
| Interconnection cable | from 15 to 20 m |
| MIG torch | 4 m for 400 A |
| Earth cable | 3 m |
| Supply cable | 4 m |
| Control panel | Basic |
| Cooling | gas per the product card |
| Processes | manual MIG/MAG |
What you get
- Kemppi FastMig KM 400 power source
- separate 4 roll wire feeder
- interconnection cable from 15 to 20 m
- MIG torch 4 m for 400 A
- earth cable 3 m
- supply cable 4 m
- short operating manual for the Basic panel
What to watch out for
A reach of up to 20 m from the source changes how work is organised: instead of rolling the machine around the structure you carry the feeder and the cable. On bridges, hulls and large tanks that most often saves a dozen or so minutes on every change of the station, and there is less movement of heavy equipment around people.
The supply is 3 x 400 V from a power socket. The product card gives gas cooling, while the description mentions a circuit led to the torch, so confirm the configuration before you buy. A long interconnection cable is an advantage and a duty at once: you watch how it is routed, because at 20 m it is easy to bend it and damage the liner, and you choose the rolls and the pressure so that the wire runs evenly along the whole length.
The Basic panel has neither pulse nor a program memory, so you build repeatability on your own notes of parameters, tied to given joints. Before you buy check the state of the interconnection cable, the liner and the contact tips in the 4 m torch and settle the set of rolls for the wire diameter you feed.
How we sell used machines
This unit was checked in our service workshop in Krotoszyn with measurements to PN-EN 60974-4 and a load test. The price includes the first year of the basic service package: an inspection with cleaning of the machine and a validation measurement. Further years can be added. We ship across the European Union, collection in person by appointment.
