EWM Tetrix 351 AC/DC Comfort is an industrial inverter TIG AC/DC power source with an MMA mode and a synergic Comfort panel. You set the current from 5 to 350 A, the TIG duty cycle is 350 A at 60% and 300 A at 100%. The supply is 3 x 400 V or 415 V, the open circuit voltage 95 V.
What this machine is for
This is a power source for steel, aluminium and special alloys in production that runs in long series. A 100% duty cycle at 300 A means work without breaks for cooling, so the machine suits thick walled structures and pipeline welding shops. With alternating current you weld aluminium, with direct current stainless, acid resistant and carbon steels.
In AC mode you choose the shape of the current curve for the material. The square curve gives the greatest arc dynamics and deep fusion, so you take it for thick sections. The sine curve makes a soft, quiet arc with a wide pool and tires the hearing less in a hall, it suits clean aluminium. The trapezoid curve joins the stability and the fusion of the square curve with a lower noise. On top of that comes the current balance, that is the proportion between breaking up the oxides and fusing into the parent material.
TIG is welding with an arc burning between a non consumable tungsten electrode and the material, under an inert gas shield, with the filler fed by hand or with no filler at all. The process goes slower than MIG/MAG, but it gives a weld without spatter and full control over the amount of heat put in, so it goes where the joint has to be tight and clean. On thin stainless sheet and on pipes every ten amperes down counts, on thick sections the reserve of current and the duty cycle.
The Comfort panel handles synergic lines. You give the material, the sheet thickness and the type of weld, and the power source picks a set of parameters, including the pulse current and the slope times. This shortens the changeover between orders and reduces the spread of parameters when the operators at the machine change. The manufacturer aimed this model at plants working in a continuous cycle, at aluminium welding shops, at the precision and sheet metal industry and at series production.
Features and equipment
- Synergic Comfort panel: the synergic lines pick the parameters once you point out the material, the thickness and the type of weld, which shortens the setup and orders the repeatability.
- AC current curve shapes, square, sine and trapezoid: you choose the arc dynamics, the depth of fusion and the noise level for a given aluminium alloy.
- AC current balance control: you set the proportion between breaking up the oxide layer and fusing into the material.
- activArc: the circuit watches the arc length and compensates the energy when the distance of the electrode from the pool changes, so the output stays steady, the electrode does not stick with a short arc, and the heat affected zone is narrower.
- spotArc: spot tacking that gives flat, repeatable points with little thermal distortion of the part.
- Spotmatic: the arc strikes from the touch of the electrode on the material itself, without pressing the torch button, which shortens the assembly of structures made of many small parts by as much as 50%.
- Current range from 5 to 350 A: one power source handles a thin wall at the lower limit and thick sections at the upper one.
- HF and Liftarc ignition: a start without touching, with high frequency, or a start by rubbing where electromagnetic disturbance gets in the way.
- MMA mode up to 350 A, with a continuous duty of 290 A at 100%: you melt thick electrodes through a whole shift, which makes the machine equipment for repair and installation work.
Technical data
| Manufacturer | EWM Hightec Welding GmbH |
|---|---|
| Type | inverter TIG AC/DC power source with an MMA mode |
| Supply | 3 x 400 V or 415 V, 50 or 60 Hz |
| TIG and MMA current range | from 5 to 350 A |
| Duty cycle 60% in TIG | 350 A at 24.0 V |
| Duty cycle 100% in TIG | 300 A at 22.0 V |
| Duty cycle 100% in MMA | 290 A |
| Open circuit voltage | 95 V DC |
| Standards and protection rating | IEC/EN 60974-1, EN 50199, IP23 |
| Panel | Synergic Comfort |
| Type of current | AC/DC |
| Cooling | liquid |
| TIG torch | 8 m |
| Earth cable | 5 m |
What you get
- EWM Tetrix 351 AC/DC Comfort power source
- TIG torch 8 m long
- earth cable 5 m
What to watch out for
The machine needs a three phase mains 3 x 400 V or 415 V at 50 or 60 Hz. A 60% duty cycle at 350 A and 24.0 V gives six minutes of welding in a ten minute window, work without a limit starts at 300 A and 22.0 V, and in MMA mode at 290 A. The open circuit voltage is 95 V, the housing has protection rating IP23, the build follows IEC/EN 60974-1 and EN 50199.
The shop catalogue data give liquid cooling, so for work at a high current you need a cooler and a working circuit, and you check the level and the cleanliness of the fluid before the start. The torch is 8 m, the earth cable 5 m, at such a length watch the bending radius of the bundle and the state of the insulation.
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.
