Operation Manual for - Mrclab.com

Ultrasonic milk analyzer6. MAKING CORRECTIONS AND RECALLIBRATION OF THEDEVICEIn the process of work with the analyser there is a possibility the results tostart differing between the data for some of the measuring parameters whenmeasured with the milk analyzer and the corresponding reference method ofanalyses (Gerber for fat, Kjeldhal for proteins etc). In order to establish thepossible discrepancy and to correct the readings of the milk analyser do thefollowing:6.1. Taking samples and preparation of samples for checking theaccurracy of the milk analyser, making corrections andrecalibrationThis is a basic moment for the correct checking the accuracy of the analyserand for making correct and precise correction and calibration. It isaccomplished according Appendix Sampling and preparation of samples forverification the accuracy of the milk analyzer, making corrections andrecalibration.6.2. Determination the type of the discrepancy:6.2.1. Making measurementsMake measurements with different samples (not less than 3) with knownvalues of a separate parameter (for example fat content), determined by theknown reference methods of analyses (for example Gerber's method fordetermination of fat content). For more accuracy it is recommended amongthese samples to be also such with values, close to the lowest and highestbounds for the measured parameters.Make 5-time measurement for each of the samples. Calculate the averagevalue for each sample parameter, without taking into consideration the firstmeasurement for each sample.6.2.2. Analysing the measurement resultsMake comparison between the values of the parameter from the referencesample and measured with the analyser. Make analyses of the differencereceived.6.2.2.1. If the received differences are relatively constant value for sampleswith different content of the analysed parameter, it is necessary to makecorrection.Operation manual 25/98