Lincoln Electric VIKING 2450 Series Operator's Manual page 7

GRIND BUTTON OPERATION
In order to switch the Auto Darkening Filter from a Cutting or Welding Shade
into Grind Mode first locate the silicone button on the left side of the helmet.
After the button has been located press and hold it for 3 seconds. A green
LED on the cartridge should blink every 3 seconds after the button is pressed
to indicate you are in Grind mode. To switch back to the previous Cutting or
Welding shade simply press and hold the button for 3 seconds. Grind mode
is intended for grinding only not for welding.
45°
90°
45°
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