Endress+Hauser Analytik Jena multi N/C 2100S User Manual

multi N/C 2100S Function and setup
37
 detection of the remaining TC content – concentration is calculated in accordance
with the calibration curve
 calculation of the TOC content in accordance with the equation (10) from the
calculated concentration difference
NOTICE
It is useful to carry out a matrix
-dependent calibration. For this the carbonate standard
is added in the range of the sample concentration to be expected. This comes closest to
the NPOC plus principle.
The TN channel is calibrated. The calculated calibration functions correspond to the
equations (6) or (7); the following applies:


= (

) (11)
The calculated parameters appear in the method in the TN analysis channel.
3.5.4 Method characteristics
The remaining standard deviation (remaining variance) expresses the dispersion of the
integers around the regression function (regression precision).
The standard deviation of the method describes in a unique and general way the quality
of the calibration. For the unique evaluation of the quality the standard deviation of the
method must be used.
The variation coefficient of the method (relative standard deviation of the method)
should be used for the comparison of different calibrations with different calibration
ranges.
The correlation coefficient compares the dispersion of the calibration measuring points
of the regression function with the total dispersion of the calibration. If all calibration
measuring points are on the calculated regression function, then the correlation
coefficient is +1 or -1. For positive correlation coefficients the regression function is
increasing, for negative ones it is decreasing.
The square of the correlation coefficient is called the coefficient of determination.
The verification limit of the calibration specifies the lowest concentration that can be
differentiated qualitatively from the zero point with a given probability. The verification
limit should always be smaller than the lowest calibration measuring point.
The detection limit of the calibration specifies the lowest concentration for which a
verification is possible with a given probability.
Calibration TN
b
Remaining standard
deviation
Standard deviation of the
method
Method variation
coefficient
Correlation coefficient
Coefficient of
determination
Limit of detection
Detection limit

Endress+Hauser Analytik Jena multi N/C 2100S Specifications

General

Brand	Endress+Hauser
Model	Analytik Jena multi N/C 2100S
Category	Measuring Instruments
Language	English