Milkotester Master Pro Operating Instructions Manual page 15

Taking samples and preparation of samples for checking the
accuracy of the milk analyzer, making corrections and recalibration
This is a basic moment for the correct checking the accuracy of the
analyzer and for making correct and precise correction and calibration. It is
accomplished according Appendix Taking and preparation of samples for
checking correctness of the milk analyzer, making corrections and
recalibration.
Determination the type of the discrepancy:
Making measurements
Make measurements with different samples (not less than 3) with
known values of a separate parameter (for example fat content),
determined by the known reference methods of analyses (for example
Gerber's method for determination of fat content). For more accuracy it is
recommended among these samples to be also such with values, close to
the lowest and highest bounds for the measured parameters.
Make 5-time measurement for each of the samples. Calculate the average
value for each sample parameter, without taking into consideration the first
measurement for each sample.
Analyzing the measurement results
Make comparison between the values of the parameter from the
reference sample and measured with the analyzer. Make analyses of the
difference received.
If the received differences are relatively constant value for samples
with different content of the analyzed parameter, it is necessary to make
correction.
For example
М% of the reference samples:
М% average when measuring
with the analyzer:
Difference:
2,20 3,00
2,38 3,17
0,18 0,17
15
Operating Instructions Master Pro
Milkotester Ltd
Ultrasonic milk analyzers
3,80 4,60 5,20
4,01 4,79 5,42
0,21 0,19 0,22