Water I.D. Primelab 2.0, Manual

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(24)
Hydrogen Peroxide LR
0.00 - 3.80 mg/l (H₂O₂)
Tablet
Internal Name: 24-Hydr-Per-LR-tab
10ml
Hydrogen Peroxide LR Photometer (TbsPHP)
Measurement procedure:
1 Fill 10 ml test water into a clean 24 mm cuvette.
2 Screw the lid back on the cuvette.
3 Insert the cuvette into the PrimeLab. Pay attention to the arrow on the front of the cuvette.
4 Start ZERO measurement.
5 Remove the cuvette again.
6 Unscrew the lid from the cuvette.
7 Empty the cuvette to a few drops.
8 Add 1 Hydr. Peroxide LR Photometer tablet(s) to the test water in the cuvette.
9 Crush the tablet with a clean stirring rod.
10 Fill the cuvette to 10 ml with the sample water.
11 Stir with the stirring rod for about 20 seconds until the reagent is completely dissolved.
12 Screw the lid back on the cuvette.
13 Insert the cuvette into the PrimeLab. Pay attention to the arrow on the front of the cuvette.
14 Tap TEST to start a 02:00 minute(s) countdown.
15 After the lapse of a 02:00 minute(s) countdown the measured value is displayed.
Notes:
If the sample water contains further oxidizing agents, these will react like hydrogen peroxide
and contribute to the measurement result.
Make sure no hydrogen peroxide escapes while preparing the sample. The measurement must
be performed directly after sampling.
The DPD reagent buffers the pH value of the sample water in the range of 6.2 to 6.5, which is
essential for colour development. If the sample water is very alkaline or acidic, this must be
adjusted to a pH within the range of 6 to 7 by addition of 0.5 mol/l sulphuric acid or 1 mol/l
caustic soda, respectively, before the DPD reagent is added.
T85/204 T85/204