Other Calculations; Blank Values; Blank Water Values; Water For Preparing Standard Solutions Preparation Water Blind Value - Endress+Hauser analytikjena multi N/C 2100 Operating Manual

4.5.5

Other calculations

For all measurements where multiple injections are carried out the mean value (MV), stand-
ard deviation (SD) and variation coefficient (VC) are calculated and displayed. For each
sample a tenfold determination can be carried out as a maximum.
Outlier selection
The control and analysis software multiWin offers the option for an automatic outlier selec-
tion. In the method a maximum limit for a variation coefficient or also for a standard deviation
can be entered.
The minimum number of measurements agreed in the method will be carried out. If the dis-
persion of the measured values is above the agreed value (SD or VC), additional injections
are carried out from the same sample until the specified maximum number of measurements
has been reached.
After each measurement the variation coefficient or standard deviation are calculated for all
combinations of measurements. If the variation coefficient or the standard deviation of at
least one combination is smaller than the specified maximum variation coefficient or stand-
ard deviation, no further measurements are carried out. The combination of measurements
with the smallest variation coefficient or the smallest standard deviation is used to calculate
the analysis results. The unused measurements are considered as outliers and deleted.
If carbon and nitrogen are determined in parallel, the outlier selection takes place separately
for each parameter.
Mean value
The mean value of the final result is calculated from the concentrations determined for the
individual detections after eliminating the outliers.
4.6

Blank values

4.6.1

Blank water values

4.6.1.1 Water for preparing standard solutions
preparation water blind value
Especially for measurements with low TOC concentrations (µg/l range) the TOC content of
the water used for preparing the standard can often not be neglected. The weighted-in
standard concentration and the TOC blank value of the preparation water are often in the
same order of magnitude. This blank value can be taken into account during calibration.
The TOC content of the preparation water is measured separately before the calibration. The
mean integer determined for the preparation water is then deducted at calibration from the
determined integer for each measuring point (gross integer).
=
The calibration function is calculated from the net integers. Mathematically this corresponds
to a parallel movement of the calibration line.
multi N/C 2100
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Edition 02.17
Technical description
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