Lovibond PoolDirect, Инструкция по эксплуатации, Страница: 23 / 78

23
PoolDirect 9in1_4i 11/2015
1.1 Methods
Notes:
1. To optimise the readings an optional batch related calibration can be performed using
Mode 40, see page 58.
2. Strong alkaline or acidic water samples must be adjusted to a pH-value between
pH 4 and 10 before the tablets are added (use 1 mol/l Hydrochloride acid resp.
1 mol/l Sodium hydroxide).
3. For accurate test results exactly 10 ml of water sample must be taken for the test.
4. This method was developed from a volumetric procedure for the determination of
Calcium Hardness. Due to undefined conditions, the deviations from the standardised
method may be greater.
5. The tolerance of the method is increasing with higher concentrations. When diluting
samples, this should be taken in account, always measuring in the first third of the
range.
6. Interferences:
• Magnesium hardness up to 200 mg/l CaCO
3
does not interfere.
• Iron concentration above 10 mg/l may cause low results.
• Zinc concentration above 5 mg/l may cause high results.
7. CaCO
3
°dH
°eH
°fH
°aH
Precision
An educated operator obtained under laboratory conditions exemplary for 2 different (one)
standard solutions the following standard deviations using different lots of reagent:
100.00 ± 10.00 mg/l; 500.00 ± 50.00 mg/l