Soham Impex SI-TIG-300, Operating Manual

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Low current High current
The intensity of the arc is proportional to the current that flows from the tungsten. The welder regulates
the welding current to adjust the power of the arc. Typically thin material requires a less powerful arc
with less heat to melt the material so less current (amps) is required, thicker material requires a more
powerful arc with more heat so more current (amps) are necessary to melt the material.

LIFT ARC IGNITION for TIG (tungsten inert gas) Welding
Lift Arc is a form of arc ignition where the machines has low voltage on the electrode to only a few volts,
with a current limit of one or two amps (well below the limit that causes metal to transfer and
contamination of the weld or electrode). When the machine detects that the tungsten has left the
surface and a spark is present, it immediately (within microseconds) increases power, converting the
spark to a full arc. It is a simple, safe lower cost alternative arc ignition process to HF (high frequency)
and a superior arc start process to scratch start.
Tungsten off the Work Tungsten Touches the Work
Arc Ignition Established TIG Arc