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CHROMIUM (VI) HIGH RANGE
• Reinsert the cuvette into the instrument and close the lid.
• Press
Timer
and the display will show the countdown prior to the measurement or, alternatively,
wait for 6 minutes and press
Read
. When the timer ends the meter will perform the reading. The
instrument displays concentration in
µg/L of chromium (Cr
6+
).
• Press
or
to access the second level functions.
• Press the
Chem Frm
key to convert the result to
µg/L of chromate (CrO
4
2¯
) and dichromate
(Cr
2
O
7
2¯
).
• Press
or
to return to the measurement screen.
INTERFERENCES
Interference may be caused by:
Vanadium above 1 ppm. However, waiting 10 minutes before reading removes the interference.
Iron above 1 ppm.
Mercurous and mercuric ions cause slight inhibition of the reaction.