Adjust refractometer for determining the AdBlue® concentration - AR14.40-P-2041-01GZB

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On equipment with automatic temperature compensation (ATC), temperature variations from 5 to 30°C/41 to 86°F are compensated automatically.

It is recommended to adjust the refractometer (5) before every checking procedure.

BLUETEC measurement gotis://D 09/14/49 01.0

Clean prism (1) and hinged lid (2) of the refractometer (5) using a soft lint-free cloth.
The prism surface should not be touched by hand.

Fig 1: Identifying Refractometer Components
Courtesy of MERCEDES-BENZ OF NORTH AMERICA.
Place 1 to 2 drops of distilled water on the prism (1) and close the hinged lid (2) using gentle pressure.
Closing of the hinged lid (2) causes the water to be distributed evenly.
See through eyepiece (4) against a light background.
Bring scales into focus by turning the eyepiece (4).
If necessary, carefully turn the adjustment screw (3) with a screwdriver, so that the bright/dark boundary is aligned with the zero line (water line).
Carefully remove any water residues from the prism (1) and hinged lid (2).