Hanna Instruments HI 83206, Instruction Manual

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Chromium VI HR
CHROMIUM VI HIGH RANGE
SPECIFICATIONS
Range 0 to 1000 µg/L
Resolution 1 µg/L
Accuracy ±5 µg/L ±4% of reading
Typical EMC ±1 µg/L
Deviation
Light Source Tungsten lamp with narrow band interference filter @ 525 nm
Method Adaptation of the ASTM Manual of Water and Environmental Technology, D1687-92,
Diphenylcarbohydrazide method. The reaction between chromium VI and the reagent
causes a purple tint in the sample.
REQUIRED REAGENTS
Code Description Quantity
HI 93723-0 Powder reagent 1 packet
REAGENT SETS
HI 93723-01 Reagents for 100 tests
HI 93723-03 Reagents for 300 tests
For other accessories see page 73.
MEASUREMENT PROCEDURE
• Select the Chromium VI HR method using the procedure described in
the Method Selection section (see page 12).
• Fill the cuvette up to the mark with 10 mL of unreacted sample and replace
the cap.
• Place the cuvette into the holder and close the lid.
• Press ZERO key. The meter will show “-0.0-” when the meter is zeroed
and ready for measurement.
• Remove the cuvette and add the content of one packet of
HI 93723-0 reagent. Replace the cap and shake vigorously
for about 10 seconds.
10 mL
• Press TIMER and the display will show the countdown prior to the measurement or, alternatively, wait
for 2 minutes and 30 seconds and press READ. When the timer ends the meter will perform the reading.
• The instrument displays the results in mg/L of total chlorine.
Note: free and total chlorine have to be measured separately with fresh unreacted samples following the
related procedure if both values are requested.
INTERFERENCES
Interference may be caused by: Bromine, Iodine, Ozone, Oxidized forms of Chromium and Manganese.
In case of water with hardness greater than 500 mg/L CaCO
3
, shake the sample for approximately 2
minutes after adding the powder reagent.
In case of water with alkalinity greater than 250 mg/L CaCO
3
or acidity greater than 150 mg/L CaCO
3
,
the color of the sample may develop only partially, or may rapidly fade. To resolve this, neutralize the
sample with diluted HCl or NaOH.
Total Chlorine