Water I.D. Primelab 2.0, Manual

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(38)
pH-value MR
6.50 - 8.40 (pH)
Tablet
Internal Name: 38-pH-MR-tab
10ml
Phenol Red Photometer (TbsPph)
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 Add 1 Phenol Red Photometer tablet(s) to the test water in the cuvette.
8 Crush the tablet with a clean stirring rod.
9 Stir with the stirring rod for about 20 seconds until the reagent is completely dissolved.
10 Screw the lid back on the cuvette.
11 Insert the cuvette into the PrimeLab. Pay attention to the arrow on the front of the cuvette.
12 Tap TEST to perform the measurement.
13 The measured value is immediately displayed.
Notes:
PH value out of the range of pH 6.5 to 8.4 can lead to incorrect test results. If you are not sure,
a control measurement by pH electrode is recommended.
An alkalinity level > 40 mg/l CaCO₃ is required to prevent inaccurate readings.
Depending on the salt content of the water sample, the measurement result must be manually
corrected according to the following scheme: 1 molar = -0.21 pH; 2 molar = -0.26 pH; 3 molar =
-0.29 pH with: 1 mol of salt (NaCl) = 5.8 % = 58.4 g/l.
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