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3.8. AC Frequency
Not adjustable in DC TIG mode. A low frequency is suited for high-current
wide-seam welding, while high frequency is suited for thin sheet and narrow seam
welding since it increases the melting speed and force. It is adjustable between
50Hz and 150Hz
3.9. AC Clean Width
In the AC TIG welding process, it indicates the percentage adjustment of negative
and positive AC half-wave widths which cleans the oxidised surface of a workpiece.
It is adjustable between 20% and 50%.
3.10. Downslope
Indicates the time the welding current is stepped down to end the arc. It is adjustable
between 0.1 and 5s.
3.11. End amps
Indicate the reduced welding current at the end of the process and is aimed at
obviating the formation of a crater at the completion of the weld. It is adjustable
between 10A and 300A.
3.12. Post flow
Indicates the time gas continues to flow after completion of the weld. The
continued gas flow will prevent oxidation of the molted metal, ensuring quality of the
weld seam and also act as a coolant. It is adjustable between 5 and 25s.
Working Principle
1. Diagram Explaining Working Principle
