Water I.D. Primelab 2.0, Manual

Page: 202 / 301

27 Gently swirl the cuvette to mix the liquid well.
28 Insert the cuvette into the PrimeLab. Pay attention to the arrow on the front of the cuvette.
29 Tap TEST to start a 02:00 minute(s) countdown.
30 After the lapse of a 02:00 minute(s) countdown the measured value is displayed.
Notes:
DPD 1 A and DPD 1 B reagent MUST be added to the vial BEFORE water sample is added to
avoid misreadings!
Make sure no ozone escapes while preparing the sample. The measurement must be
performed directly after sampling.
Shake the liquid reagent thoroughly before adding the liquid to the vial.
Liquid reagents should be stored at temperatures of 5 - 10 °C in securely closed bottles.
If the sample water contains further oxidizing agents, these will react like ozone and contribute
to the measurement result.
If the sample water contains more than 30 mg/l ozone, a measured value of 0 mg/l can be
displayed. In that case, a dilution is recommended.
Turbidity caused by high concentration of calcium ions will affect the measurement result. To
prevent that, please use DPD HC (High Calcium) reagents.
Do not clean glassware and equipment with household detergents, as these could greatly
reduce the measurement result. To prevent any contamination, the cuvette, lid and stirrer
should be stored in a 0.1 % sodium hypochlorite solution for one hour. Then rinse with distilled
water, thoroughly.
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.
T147/204 T147/204