Understanding Duty Cycle Before You Buy An Inverter Welder
Every workshop is different, so rather than relying on general advice, it's worth getting your own set-up properly assessed. A system that works well for one shop can be quite wrong for another with different ventilation, floor space or process mix, and an on-torch extraction option, such as those available for Fronius torches, suits a different layout to a fixed overhead hood.
The figure changes with output. Turn the amperage down and the duty cycle climbs, because the internal components are working less hard. This is why a welder can feel completely different in a busy production environment compared with occasional home workshop use: someone welding continuously through a shift needs a much higher duty cycle at their working amperage than someone doing short repair jobs a few times a week. It's the kind of spec worth comparing properly across brands such as Kemppi and EWM, not just reading off the headline amperage figure.
Portability and durability matter depending on how the table gets used. A shop building large frames or vehicle chassis needs a solid, well-supported table that won't flex under load, while a mobile fabricator or someone working across multiple sites benefits more from a lighter, foldable design. Material and construction quality affect long-term flatness too, since a table that warps under heat from repeated welding stops being reliable exactly where it matters most.
Shade range and sensor count are the two specifications that matter most in daily use. A wider variable shade range lets one helmet cover a broader spread of processes and amperages, from low-amp TIG work through to higher-output MIG or MMA, without swapping cartridges. More sensors generally mean the filter is less likely to miss a low-angle arc or a strike caught at an awkward viewing angle, which matters most for TIG welding where the arc can be harder for a sensor to pick up cleanly.
Duty cycle is one of the most misunderstood figures on a welder's spec sheet, yet it tells you more about real-world usability than the headline amperage does. It's expressed as a percentage over a ten-minute period at a given output, so a machine rated at 30% duty cycle at its maximum amperage can run for three minutes out of every ten at that setting before it needs to rest and cool.
The abrasive material itself matters as much as the shape. Discs formulated for steel typically contain aluminium oxide, while stainless steel usually calls for an inox-rated disc that's free from iron, www.tecproducts.co.uk sulphur and chlorine contaminants that could otherwise cause surface corrosion on the stainless. Aluminium and other soft, non-ferrous metals need their own dedicated abrasives too, since standard steel discs tend to clog quickly and produce a poor finish on softer materials.