23
4
Ammonia HR
•
Press the
Zero
key. The display will show “
-0.0-
” when the meter is zeroed and ready for
measurement.
•
Remove the vial.
•
Remove the cap and add 4 drops of HI 93764-0 Nessler
Reagent.
• Replace the cap tightly and mix by inverting the vial a couple
of times. This is the sample.
•
Place the vial into the holder and push it completely down.
• Press
Timer
and the display will show the countdown prior to
the measurement and the message “
Reaction Time
”.
Alternatively, wait for 3 minutes and 30 seconds and press
Read
. The instrument will perform the reading.
• The instrument displays concentration in
mg/L of ammonia nitrogen (NH
3
-N)
. Press
s
or
t
to
convert the result in mg/L ammonia (NH
3
).
INTERFERENCES
Interference may be caused by:
• Organic compounds like: chloramines, various aliphatic and aromatic amines, glycine or urea above 100 ppm.
To eliminate these interferences distillation is required.
• Organic compounds like: aldehydes, alcohols (e.g. ethanol) or acetone above 1 %.
To eliminate these interferences distillation is required.
• Sulfide: may cause turbidity.