Hanna Instruments HI 83200C User Manual

Page 48

Dissolved Oxygen

SPECIFICATIONS

Range

0.0 to 10.0 mg/L

Resolution

0.1 mg/L

Accuracy

±0.4 mg/L ±3% of reading at 25 °C

Typical EMC

± 0.1 mg/L

Deviation
Light Source

Tungsten lamp with narrow band interference filter @ 420 nm

Method

Adaptation of the

Standard Methods for the Examination of Water and Wastewater,

edition, Azide modified Winkler method. The reaction between dissolved oxygen

and the reagents causes a yellow tint in the sample.

REQUIRED REAGENTS

Code

Description

Quantity

HI 93732

A-0

Reagent A

5 drops

HI 93732

B-0

Reagent B

5 drops

HI 93732

C-0

Reagent C

10 drops

REAGENT SET

HI 93732-01 Reagents for 100 tests
HI 93732-03 Reagents for 300 tests
For other accessories see page 128.

MEASUREMENT PROCEDURE

• Select the

Dissolved Oxygen method using the procedure described in

the

Method Selection section (see page 12).

• Fill one 60 mL glass bottle completely with the unreacted sample.

• Replace the cap and ensure that a small part of the sample spills

over.

• Remove the cap and add 5 drops of HI 93732A-0 and 5 drops of

HI 93732B-0.

• Add more sample, to fill the bottle completely. Replace the cap

again and ensure that a part of the sample spills over. This is to
make sure that no air bubbles have been trapped inside, which
could alter the reading.

• Invert several times the bottle. The sample becomes orange-yellow

and a flocculent agent will appear.

DISSOLVED OXYGEN

• Reinsert the cuvette into the instrument.

• 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

mg/L of nitrite.

• Press ▲ or ▼ to access the second level functions.
• Press the

Chem Frm key to convert the result in mg/L of nitrogen-nitrite (NO

¯-N) and sodium nitrite

(NaNO

• Press ▲ or ▼ to return to the measurement screen.

INTERFERENCES

Interference may be caused by the following ions:
ferrous, ferric, cupric, mercurous, silver, antimonious, bismuth, auric, lead, metavanadate and chloroplatinate.
Strongly reducing and oxidizing reagents.
High levels of nitrate (above 100 mg/L) could yield falsely high readings due to a minute amount of
reduction to nitrite that could occur at these levels.

Nitrite LR