User Guide

11
• Whenever the cuvet is placed into
the measurement cell, it must be
dry outside, and completely free of
fingerprints, oil or dirt. Wipe it
thoroughly with HI 731318 or a
lint-free cloth prior to insertion.
• It is possible to take multiple
readings in a row, but it is
recommended to take a new zero
reading for each sample and to use
the same cuvet for zeroing and
measurement.
• It is important to discard the sample immediately after the reading
is taken because the glass might become permanently stained.
• All the reaction times reported in this manual are referred to 20°C
(68°F). As a general rule of thumb, they should be doubled at
10°C (50°F) and halved at 30°C (86°F).
42
• Press ZERO and “SIP” will appear on the display.
• Wait for a few seconds and the display will
show “-0.0-”. Now the meter is zeroed
and ready for measurement.
• Remove the cuvet and add
the content of one packet
of HI 93750B reagent. Re-
place the cap and mix
gently for one minute by
turning slowly the cuvet up-
side down.
• Reinsert the cuvet into the instrument.
• Press TIMER and the display will show the countdown prior to the
measurement or, alternatively, wait for 2 minutes and press READ
DIRECT. In both cases “SIP” will blink during measurement.
• The instrument directly displays concentration in mg/L (ppm) of
potassium (K).
• To convert the reading to mg/L of potassium oxide (K
2
O), multiply
by a factor of 1.20.
INTERFERENCES
The following ions do not interfere below the concentrations reported:
Ammonium 10 ppm
Calcium 10000 ppm as CaCO
3
Chloride 12000 ppm
Magnesium 8000 ppm as CaCO
3
Sodium 8000 ppm
Potassium MR
HI 83215 - NUTRIENT ANALYSES
Code Parameter Page
1 Ammonia LR 21
2 Ammonia MR 23
3 Ammonia HR 25
4 Nitrate LR 27
5 Nitrate MR 29
6 Nitrate HR 31
Code Parameter Page
7 Phosphorus LR 33
8 Phosphorus MR 35
9 Phosphorus HR 37
10 Potassium LR 39
11 Potassium MR 41
12 Potassium HR 43
PARAMETERS REFERENCE TABLE