Maintenance
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Recipes of the span solution from a concentrated solution
How to determine the suitable span solution for the turbidity meter
Confirm the turbidity standard substance beforehand.
The turbidity standard substance might be selected from Kaolin, Formazin and PSL.
The average turbidity should be in consideration.
The deviation of the turbidity should be in consideration.
In the case of low turbidity measurement; for example city water, swimming pool
water
For the low turbidity measurement less than 1 degree, the optimum turbidity for span
calibration is made by dilution of the concentrated solution between 2 degrees and 10
degrees.
In the case of unstable turbidity measurement; for example treatment water, river
water
Set the recording range which covers the maximum turbidity if the data fluctuate.
Determine the span solution between 0.3 and 0.9 of the recording full scale range and make it
by dilution.
How to dilute concentrated solution with water for any span solution
Any span solution from Kaolin 10000 degrees
Span solution A degree: Take A/10 mL of Kaolin 10000 degrees solution and fill up to 1 L by
water.
For the example A
50: Take 5 mL (50/10) of Kaolin 10000 degrees solution and fill up to 1 L
by water.
Reference
For the calibration liquid preparation procedure, refer to “ Kaolin standard solution ” (page 80).
Any span solution from Formazin 4000 degrees
Span solution B degree: Take B/4 mL of Formazin 4000 degrees solution and fill up to 1 L by
water.
For the example B
40: Take 10 mL (40/4) of Formazin 4000 degrees solution and fill up to 1
L by water.
Reference
For the calibration liquid preparation procedure, refer to “ Preparation method of calibration solution ”
(page 79).
Any span solution from PSL 100 degrees
Span solution C degree: Take C
10 mL of PSL 100 degrees solution and fill up to 1 L by
water.
For the example C
2: Take 20 mL (2
10) of PSL 100 degrees solution and fill up to 1 L by
water.
