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4.2
Output Current Mode Selection
1.
Press ‘MODE’ button (20) until the desired Welding Process Indicator Light (21 or 22) is lit.
Figure 8
4.2.1
DC (Direct Current)
Direct Current. This is suitable for TIG welding ferrous (iron based) metals such as mild steel and
stainless steel, copper and titanium and also suitable for most Stick/MMA welding.
See 12.3.1 for more information.
4.2.2
AC (Alternating Current)
This is required for welding reactive metals such as Aluminium, Magnesium and Zinc. When reactive
metals are exposed to air they form an oxide layer that insulates the base metal and prevents welding
current flowing, it also contaminates the weld pool. Reverse current flow is required to break through/
clean off this oxide layer so that welding can take place, while the current flow during the positive
cycle does the majority of the heating of the weld pool area. This is also used for some specialty
Stick/MMA welding.
See 12.3.2 for more information.
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